style cleanup: follow style guide for formatting of if/for/while loops, and else...
[blender.git] / source / blender / editors / sculpt_paint / paint_image.c
1 /*
2  * imagepaint.c
3  *
4  * Functions to paint images in 2D and 3D.
5  * 
6  * ***** BEGIN GPL LICENSE BLOCK *****
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * as published by the Free Software Foundation; either version 2
11  * of the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * along with this program; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
20  *
21  * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
22  * All rights reserved.
23  *
24  * The Original Code is: some of this file.
25  *
26  * Contributor(s): Jens Ole Wund (bjornmose), Campbell Barton (ideasman42)
27  *
28  * ***** END GPL LICENSE BLOCK *****
29  */
30
31 /** \file blender/editors/sculpt_paint/paint_image.c
32  *  \ingroup edsculpt
33  */
34
35
36 #include <float.h>
37 #include <string.h>
38 #include <stdio.h>
39 #include <math.h>
40
41 #include "MEM_guardedalloc.h"
42
43 #ifdef WIN32
44 #include "BLI_winstuff.h"
45 #endif
46 #include "BLI_math.h"
47 #include "BLI_blenlib.h"
48 #include "BLI_dynstr.h"
49 #include "BLI_linklist.h"
50 #include "BLI_memarena.h"
51 #include "BLI_threads.h"
52 #include "BLI_utildefines.h"
53
54 #include "PIL_time.h"
55
56 #include "IMB_imbuf.h"
57 #include "IMB_imbuf_types.h"
58
59 #include "DNA_brush_types.h"
60 #include "DNA_camera_types.h"
61 #include "DNA_mesh_types.h"
62 #include "DNA_meshdata_types.h"
63 #include "DNA_node_types.h"
64 #include "DNA_object_types.h"
65 #include "DNA_scene_types.h"
66 #include "DNA_texture_types.h"
67
68 #include "BKE_camera.h"
69 #include "BKE_context.h"
70 #include "BKE_depsgraph.h"
71 #include "BKE_DerivedMesh.h"
72 #include "BKE_idprop.h"
73 #include "BKE_brush.h"
74 #include "BKE_image.h"
75 #include "BKE_library.h"
76 #include "BKE_main.h"
77 #include "BKE_mesh.h"
78 #include "BKE_node.h"
79 #include "BKE_object.h"
80 #include "BKE_paint.h"
81 #include "BKE_report.h"
82 #include "BKE_scene.h"
83 #include "BKE_global.h"
84 #include "BKE_deform.h"
85
86 #include "BKE_tessmesh.h"
87
88 #include "BIF_gl.h"
89 #include "BIF_glutil.h"
90
91 #include "UI_view2d.h"
92
93 #include "ED_image.h"
94 #include "ED_screen.h"
95 #include "ED_sculpt.h"
96 #include "ED_uvedit.h"
97 #include "ED_view3d.h"
98 #include "ED_mesh.h"
99
100 #include "WM_api.h"
101 #include "WM_types.h"
102
103 #include "RNA_access.h"
104 #include "RNA_define.h"
105 #include "RNA_enum_types.h"
106
107 #include "GPU_draw.h"
108 #include "GPU_extensions.h"
109
110 #include "paint_intern.h"
111
112 /* Defines and Structs */
113
114 #define IMAPAINT_CHAR_TO_FLOAT(c) ((c)/255.0f)
115
116 #define IMAPAINT_FLOAT_RGB_TO_CHAR(c, f)  {                                   \
117         (c)[0]= FTOCHAR((f)[0]);                                                  \
118         (c)[1]= FTOCHAR((f)[1]);                                                  \
119         (c)[2]= FTOCHAR((f)[2]);                                                  \
120 }
121 #define IMAPAINT_FLOAT_RGBA_TO_CHAR(c, f)  {                                  \
122         (c)[0]= FTOCHAR((f)[0]);                                                  \
123         (c)[1]= FTOCHAR((f)[1]);                                                  \
124         (c)[2]= FTOCHAR((f)[2]);                                                  \
125         (c)[3]= FTOCHAR((f)[3]);                                                  \
126 }
127 #define IMAPAINT_CHAR_RGB_TO_FLOAT(f, c)  {                                   \
128         (f)[0]= IMAPAINT_CHAR_TO_FLOAT((c)[0]);                                   \
129         (f)[1]= IMAPAINT_CHAR_TO_FLOAT((c)[1]);                                   \
130         (f)[2]= IMAPAINT_CHAR_TO_FLOAT((c)[2]);                                   \
131 }
132 #define IMAPAINT_CHAR_RGBA_TO_FLOAT(f, c)  {                                  \
133         (f)[0]= IMAPAINT_CHAR_TO_FLOAT((c)[0]);                                   \
134         (f)[1]= IMAPAINT_CHAR_TO_FLOAT((c)[1]);                                   \
135         (f)[2]= IMAPAINT_CHAR_TO_FLOAT((c)[2]);                                   \
136         (f)[3]= IMAPAINT_CHAR_TO_FLOAT((c)[3]);                                   \
137 }
138
139 #define IMAPAINT_FLOAT_RGB_COPY(a, b) copy_v3_v3(a, b)
140
141 #define IMAPAINT_TILE_BITS                      6
142 #define IMAPAINT_TILE_SIZE                      (1 << IMAPAINT_TILE_BITS)
143 #define IMAPAINT_TILE_NUMBER(size)      (((size)+IMAPAINT_TILE_SIZE-1) >> IMAPAINT_TILE_BITS)
144
145 static void imapaint_image_update(SpaceImage *sima, Image *image, ImBuf *ibuf, short texpaint);
146
147
148 typedef struct ImagePaintState {
149         SpaceImage *sima;
150         View2D *v2d;
151         Scene *scene;
152         bScreen *screen;
153
154         Brush *brush;
155         short tool, blend;
156         Image *image;
157         ImBuf *canvas;
158         ImBuf *clonecanvas;
159         short clonefreefloat;
160         char *warnpackedfile;
161         char *warnmultifile;
162
163         /* texture paint only */
164         Object *ob;
165         Mesh *me;
166         int faceindex;
167         float uv[2];
168 } ImagePaintState;
169
170 typedef struct ImagePaintPartialRedraw {
171         int x1, y1, x2, y2;
172         int enabled;
173 } ImagePaintPartialRedraw;
174
175 typedef struct ImagePaintRegion {
176         int destx, desty;
177         int srcx, srcy;
178         int width, height;
179 } ImagePaintRegion;
180
181 /* ProjectionPaint defines */
182
183 /* approx the number of buckets to have under the brush,
184  * used with the brush size to set the ps->buckets_x and ps->buckets_y value.
185  * 
186  * When 3 - a brush should have ~9 buckets under it at once
187  * ...this helps for threading while painting as well as
188  * avoiding initializing pixels that wont touch the brush */
189 #define PROJ_BUCKET_BRUSH_DIV 4
190
191 #define PROJ_BUCKET_RECT_MIN 4
192 #define PROJ_BUCKET_RECT_MAX 256
193
194 #define PROJ_BOUNDBOX_DIV 8
195 #define PROJ_BOUNDBOX_SQUARED  (PROJ_BOUNDBOX_DIV * PROJ_BOUNDBOX_DIV)
196
197 //#define PROJ_DEBUG_PAINT 1
198 //#define PROJ_DEBUG_NOSEAMBLEED 1
199 //#define PROJ_DEBUG_PRINT_CLIP 1
200 #define PROJ_DEBUG_WINCLIP 1
201
202 /* projectFaceSeamFlags options */
203 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
204 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
205 #define PROJ_FACE_SEAM1 (1<<0)  /* If this face has a seam on any of its edges */
206 #define PROJ_FACE_SEAM2 (1<<1)
207 #define PROJ_FACE_SEAM3 (1<<2)
208 #define PROJ_FACE_SEAM4 (1<<3)
209
210 #define PROJ_FACE_NOSEAM1       (1<<4)
211 #define PROJ_FACE_NOSEAM2       (1<<5)
212 #define PROJ_FACE_NOSEAM3       (1<<6)
213 #define PROJ_FACE_NOSEAM4       (1<<7)
214
215 #define PROJ_SRC_VIEW           1
216 #define PROJ_SRC_IMAGE_CAM      2
217 #define PROJ_SRC_IMAGE_VIEW     3
218
219 #define PROJ_VIEW_DATA_ID "view_data"
220 #define PROJ_VIEW_DATA_SIZE (4*4 + 4*4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
221
222
223 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
224  * as this number approaches  1.0f the likelihood increases of float precision errors where
225  * it is occluded by an adjacent face */
226 #define PROJ_FACE_SCALE_SEAM    0.99f
227
228 #define PROJ_BUCKET_NULL                0
229 #define PROJ_BUCKET_INIT                (1<<0)
230 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
231
232 /* used for testing doubles, if a point is on a line etc */
233 #define PROJ_GEOM_TOLERANCE 0.00075f
234
235 /* vert flags */
236 #define PROJ_VERT_CULL 1
237
238 #define PI_80_DEG ((M_PI_2 / 9) * 8)
239
240 /* This is mainly a convenience struct used so we can keep an array of images we use
241  * Thir imbufs, etc, in 1 array, When using threads this array is copied for each thread
242  * because 'partRedrawRect' and 'touch' values would not be thread safe */
243 typedef struct ProjPaintImage {
244         Image *ima;
245         ImBuf *ibuf;
246         ImagePaintPartialRedraw *partRedrawRect;
247         void **undoRect; /* only used to build undo tiles after painting */
248         int touch;
249 } ProjPaintImage;
250
251 /* Main projection painting struct passed to all projection painting functions */
252 typedef struct ProjPaintState {
253         View3D *v3d;
254         RegionView3D *rv3d;
255         ARegion *ar;
256         Scene *scene;
257         int source; /* PROJ_SRC_**** */
258
259         Brush *brush;
260         short tool, blend;
261         Object *ob;
262         /* end similarities with ImagePaintState */
263         
264         DerivedMesh    *dm;
265         int                     dm_totface;
266         int                     dm_totvert;
267         int                             dm_release;
268         
269         MVert              *dm_mvert;
270         MFace              *dm_mface;
271         MTFace             *dm_mtface;
272         MTFace             *dm_mtface_clone;    /* other UV map, use for cloning between layers */
273         MTFace             *dm_mtface_stencil;
274         
275         /* projection painting only */
276         MemArena *arena_mt[BLENDER_MAX_THREADS];/* for multithreading, the first item is sometimes used for non threaded cases too */
277         LinkNode **bucketRect;                          /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
278         LinkNode **bucketFaces;                         /* bucketRect aligned array linkList of faces overlapping each bucket */
279         unsigned char *bucketFlags;                                     /* store if the bucks have been initialized  */
280 #ifndef PROJ_DEBUG_NOSEAMBLEED
281         char *faceSeamFlags;                            /* store info about faces, if they are initialized etc*/
282         float (*faceSeamUVs)[4][2];                     /* expanded UVs for faces to use as seams */
283         LinkNode **vertFaces;                           /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
284 #endif
285         char *vertFlags;                                        /* store options per vert, now only store if the vert is pointing away from the view */
286         int buckets_x;                                          /* The size of the bucket grid, the grid span's screenMin/screenMax so you can paint outsize the screen or with 2 brushes at once */
287         int buckets_y;
288         
289         ProjPaintImage *projImages;
290         
291         int image_tot;                          /* size of projectImages array */
292         
293         float (*screenCoords)[4];       /* verts projected into floating point screen space */
294         
295         float screenMin[2];                     /* 2D bounds for mesh verts on the screen's plane (screenspace) */
296         float screenMax[2]; 
297         float screen_width;                     /* Calculated from screenMin & screenMax */
298         float screen_height;
299         int winx, winy;                         /* from the carea or from the projection render */
300         
301         /* options for projection painting */
302         int do_layer_clone;
303         int do_layer_stencil;
304         int do_layer_stencil_inv;
305         
306         short do_occlude;                       /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
307         short do_backfacecull;  /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
308         short do_mask_normal;                   /* mask out pixels based on their normals */
309         short do_new_shading_nodes;     /* cache scene_use_new_shading_nodes value */
310         float normal_angle;                             /* what angle to mask at*/
311         float normal_angle_inner;
312         float normal_angle_range;               /* difference between normal_angle and normal_angle_inner, for easy access */
313         
314         short is_ortho;
315         short is_airbrush;                                      /* only to avoid using (ps.brush->flag & BRUSH_AIRBRUSH) */
316         short is_texbrush;                                      /* only to avoid running  */
317 #ifndef PROJ_DEBUG_NOSEAMBLEED
318         float seam_bleed_px;
319 #endif
320         /* clone vars */
321         float cloneOffset[2];
322         
323         float projectMat[4][4];         /* Projection matrix, use for getting screen coords */
324         float viewDir[3];                       /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
325         float viewPos[3];                       /* View location in object relative 3D space, so can compare to verts  */
326         float clipsta, clipend;
327         
328         /* reproject vars */
329         Image *reproject_image;
330         ImBuf *reproject_ibuf;
331
332
333         /* threads */
334         int thread_tot;
335         int bucketMin[2];
336         int bucketMax[2];
337         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
338 } ProjPaintState;
339
340 typedef union pixelPointer
341 {
342         float *f_pt;                    /* float buffer */
343         unsigned int *uint_pt; /* 2 ways to access a char buffer */
344         unsigned char *ch_pt;
345 } PixelPointer;
346
347 typedef union pixelStore
348 {
349         unsigned char ch[4];
350         unsigned int uint;
351         float f[4];
352 } PixelStore;
353
354 typedef struct ProjPixel {
355         float projCoSS[2]; /* the floating point screen projection of this pixel */
356         
357         /* Only used when the airbrush is disabled.
358          * Store the max mask value to avoid painting over an area with a lower opacity
359          * with an advantage that we can avoid touching the pixel at all, if the 
360          * new mask value is lower then mask_max */
361         unsigned short mask_max;
362         
363         /* for various reasons we may want to mask out painting onto this pixel */
364         unsigned short mask;
365         
366         short x_px, y_px;
367         
368         PixelStore origColor;
369         PixelStore newColor;
370         PixelPointer pixel;
371         
372         short image_index; /* if anyone wants to paint onto more then 32768 images they can bite me */
373         unsigned char bb_cell_index;
374 } ProjPixel;
375
376 typedef struct ProjPixelClone {
377         struct ProjPixel __pp;
378         PixelStore clonepx;
379 } ProjPixelClone;
380
381 /* Finish projection painting structs */
382
383 typedef struct UndoImageTile {
384         struct UndoImageTile *next, *prev;
385
386         char idname[MAX_ID_NAME];       /* name instead of pointer*/
387         char ibufname[IB_FILENAME_SIZE];
388
389         void *rect;
390         int x, y;
391
392         short source, use_float;
393         char gen_type;
394 } UndoImageTile;
395
396 static ImagePaintPartialRedraw imapaintpartial = {0, 0, 0, 0, 0};
397
398 /* UNDO */
399
400 static void undo_copy_tile(UndoImageTile *tile, ImBuf *tmpibuf, ImBuf *ibuf, int restore)
401 {
402         /* copy or swap contents of tile->rect and region in ibuf->rect */
403         IMB_rectcpy(tmpibuf, ibuf, 0, 0, tile->x*IMAPAINT_TILE_SIZE,
404                 tile->y*IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE);
405
406         if (ibuf->rect_float) {
407                 SWAP(void*, tmpibuf->rect_float, tile->rect);
408         }
409         else {
410                 SWAP(void*, tmpibuf->rect, tile->rect);
411         }
412         
413         if (restore)
414                 IMB_rectcpy(ibuf, tmpibuf, tile->x*IMAPAINT_TILE_SIZE,
415                         tile->y*IMAPAINT_TILE_SIZE, 0, 0, IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE);
416 }
417
418 static void *image_undo_push_tile(Image *ima, ImBuf *ibuf, ImBuf **tmpibuf, int x_tile, int y_tile)
419 {
420         ListBase *lb= undo_paint_push_get_list(UNDO_PAINT_IMAGE);
421         UndoImageTile *tile;
422         int allocsize;
423         short use_float = ibuf->rect_float ? 1 : 0;
424
425         for (tile=lb->first; tile; tile=tile->next)
426                 if (tile->x == x_tile && tile->y == y_tile && ima->gen_type == tile->gen_type && ima->source == tile->source)
427                         if (tile->use_float == use_float)
428                                 if (strcmp(tile->idname, ima->id.name)==0 && strcmp(tile->ibufname, ibuf->name)==0)
429                                         return tile->rect;
430         
431         if (*tmpibuf==NULL)
432                 *tmpibuf = IMB_allocImBuf(IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, 32, IB_rectfloat|IB_rect);
433         
434         tile= MEM_callocN(sizeof(UndoImageTile), "UndoImageTile");
435         BLI_strncpy(tile->idname, ima->id.name, sizeof(tile->idname));
436         tile->x= x_tile;
437         tile->y= y_tile;
438
439         allocsize= IMAPAINT_TILE_SIZE*IMAPAINT_TILE_SIZE*4;
440         allocsize *= (ibuf->rect_float)? sizeof(float): sizeof(char);
441         tile->rect= MEM_mapallocN(allocsize, "UndeImageTile.rect");
442
443         BLI_strncpy(tile->ibufname, ibuf->name, sizeof(tile->ibufname));
444
445         tile->gen_type= ima->gen_type;
446         tile->source= ima->source;
447         tile->use_float= use_float;
448
449         undo_copy_tile(tile, *tmpibuf, ibuf, 0);
450         undo_paint_push_count_alloc(UNDO_PAINT_IMAGE, allocsize);
451
452         BLI_addtail(lb, tile);
453         
454         return tile->rect;
455 }
456
457 static void image_undo_restore(bContext *C, ListBase *lb)
458 {
459         Main *bmain= CTX_data_main(C);
460         Image *ima = NULL;
461         ImBuf *ibuf, *tmpibuf;
462         UndoImageTile *tile;
463
464         tmpibuf= IMB_allocImBuf(IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, 32,
465                                                         IB_rectfloat|IB_rect);
466         
467         for (tile=lb->first; tile; tile=tile->next) {
468                 short use_float;
469
470                 /* find image based on name, pointer becomes invalid with global undo */
471                 if (ima && strcmp(tile->idname, ima->id.name)==0) {
472                         /* ima is valid */
473                 }
474                 else {
475                         ima= BLI_findstring(&bmain->image, tile->idname, offsetof(ID, name));
476                 }
477
478                 ibuf= BKE_image_get_ibuf(ima, NULL);
479
480                 if (ima && ibuf && strcmp(tile->ibufname, ibuf->name)!=0) {
481                         /* current ImBuf filename was changed, probably current frame
482                          * was changed when paiting on image sequence, rather than storing
483                          * full image user (which isn't so obvious, btw) try to find ImBuf with
484                          * matched file name in list of already loaded images */
485
486                         ibuf= BLI_findstring(&ima->ibufs, tile->ibufname, offsetof(ImBuf, name));
487                 }
488
489                 if (!ima || !ibuf || !(ibuf->rect || ibuf->rect_float))
490                         continue;
491
492                 if (ima->gen_type != tile->gen_type || ima->source != tile->source)
493                         continue;
494
495                 use_float = ibuf->rect_float ? 1 : 0;
496
497                 if (use_float != tile->use_float)
498                         continue;
499
500                 undo_copy_tile(tile, tmpibuf, ibuf, 1);
501
502                 GPU_free_image(ima); /* force OpenGL reload */
503                 if (ibuf->rect_float)
504                         ibuf->userflags |= IB_RECT_INVALID; /* force recreate of char rect */
505                 if (ibuf->mipmap[0])
506                         ibuf->userflags |= IB_MIPMAP_INVALID; /* force mipmap recreatiom */
507
508         }
509
510         IMB_freeImBuf(tmpibuf);
511 }
512
513 static void image_undo_free(ListBase *lb)
514 {
515         UndoImageTile *tile;
516
517         for (tile=lb->first; tile; tile=tile->next)
518                 MEM_freeN(tile->rect);
519 }
520
521 /* get active image for face depending on old/new shading system */
522
523 static Image *imapaint_face_image(const ImagePaintState *s, int face_index)
524 {
525         Image *ima;
526
527         if (scene_use_new_shading_nodes(s->scene)) {
528                 MFace *mf = s->me->mface+face_index;
529                 ED_object_get_active_image(s->ob, mf->mat_nr, &ima, NULL, NULL);
530         }
531         else {
532                 MTFace *tf = s->me->mtface+face_index;
533                 ima = tf->tpage;
534         }
535
536         return ima;
537 }
538
539 static Image *project_paint_face_image(const ProjPaintState *ps, MTFace *dm_mtface, int face_index)
540 {
541         Image *ima;
542
543         if (ps->do_new_shading_nodes) { /* cached scene_use_new_shading_nodes result */
544                 MFace *mf = ps->dm_mface+face_index;
545                 ED_object_get_active_image(ps->ob, mf->mat_nr, &ima, NULL, NULL);
546         }
547         else {
548                 ima = dm_mtface[face_index].tpage;
549         }
550
551         return ima;
552 }
553
554 /* fast projection bucket array lookup, use the safe version for bound checking  */
555 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
556 {
557         /* If we were not dealing with screenspace 2D coords we could simple do...
558          * ps->bucketRect[x + (y*ps->buckets_y)] */
559         
560         /* please explain?
561          * projCoSS[0] - ps->screenMin[0]       : zero origin
562          * ... / ps->screen_width                               : range from 0.0 to 1.0
563          * ... * ps->buckets_x          : use as a bucket index
564          *
565          * Second multiplication does similar but for vertical offset
566          */
567         return  (       (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) + 
568                 (       (       (int)(((projCoSS[1] - ps->screenMin[1])  / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
569 }
570
571 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
572 {
573         int bucket_index = project_bucket_offset(ps, projCoSS);
574         
575         if (bucket_index < 0 || bucket_index >= ps->buckets_x*ps->buckets_y) {  
576                 return -1;
577         }
578         else {
579                 return bucket_index;
580         }
581 }
582
583 /* still use 2D X,Y space but this works for verts transformed by a perspective matrix, using their 4th component as a weight */
584 static void barycentric_weights_v2_persp(float v1[4], float v2[4], float v3[4], float co[2], float w[3])
585 {
586         float wtot_inv, wtot;
587
588         w[0] = area_tri_signed_v2(v2, v3, co) / v1[3];
589         w[1] = area_tri_signed_v2(v3, v1, co) / v2[3];
590         w[2] = area_tri_signed_v2(v1, v2, co) / v3[3];
591         wtot = w[0]+w[1]+w[2];
592
593         if (wtot != 0.0f) {
594                 wtot_inv = 1.0f/wtot;
595
596                 w[0] = w[0]*wtot_inv;
597                 w[1] = w[1]*wtot_inv;
598                 w[2] = w[2]*wtot_inv;
599         }
600         else /* dummy values for zero area face */
601                 w[0] = w[1] = w[2] = 1.0f/3.0f;
602 }
603
604 static float VecZDepthOrtho(float pt[2], float v1[3], float v2[3], float v3[3], float w[3])
605 {
606         barycentric_weights_v2(v1, v2, v3, pt, w);
607         return (v1[2]*w[0]) + (v2[2]*w[1]) + (v3[2]*w[2]);
608 }
609
610 static float VecZDepthPersp(float pt[2], float v1[4], float v2[4], float v3[4], float w[3])
611 {
612         float wtot_inv, wtot;
613         float w_tmp[3];
614
615         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
616         /* for the depth we need the weights to match what
617          * barycentric_weights_v2 would return, in this case its easiest just to
618          * undo the 4th axis division and make it unit-sum
619          *
620          * don't call barycentric_weights_v2() becaue our callers expect 'w'
621          * to be weighted from the perspective */
622         w_tmp[0]= w[0] * v1[3];
623         w_tmp[1]= w[1] * v2[3];
624         w_tmp[2]= w[2] * v3[3];
625
626         wtot = w_tmp[0]+w_tmp[1]+w_tmp[2];
627
628         if (wtot != 0.0f) {
629                 wtot_inv = 1.0f/wtot;
630
631                 w_tmp[0] = w_tmp[0]*wtot_inv;
632                 w_tmp[1] = w_tmp[1]*wtot_inv;
633                 w_tmp[2] = w_tmp[2]*wtot_inv;
634         }
635         else /* dummy values for zero area face */
636                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f/3.0f;
637         /* done mimicing barycentric_weights_v2() */
638
639         return (v1[2]*w_tmp[0]) + (v2[2]*w_tmp[1]) + (v3[2]*w_tmp[2]);
640 }
641
642
643 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
644 static int project_paint_PickFace(const ProjPaintState *ps, float pt[2], float w[3], int *side)
645 {
646         LinkNode *node;
647         float w_tmp[3];
648         float *v1, *v2, *v3, *v4;
649         int bucket_index;
650         int face_index;
651         int best_side = -1;
652         int best_face_index = -1;
653         float z_depth_best = FLT_MAX, z_depth;
654         MFace *mf;
655         
656         bucket_index = project_bucket_offset_safe(ps, pt);
657         if (bucket_index==-1)
658                 return -1;
659         
660         
661         
662         /* we could return 0 for 1 face buckets, as long as this function assumes
663          * that the point its testing is only every originated from an existing face */
664         
665         for (node= ps->bucketFaces[bucket_index]; node; node= node->next) {
666                 face_index = GET_INT_FROM_POINTER(node->link);
667                 mf= ps->dm_mface + face_index;
668                 
669                 v1= ps->screenCoords[mf->v1];
670                 v2= ps->screenCoords[mf->v2];
671                 v3= ps->screenCoords[mf->v3];
672                 
673                 if (isect_point_tri_v2(pt, v1, v2, v3)) {
674                         if (ps->is_ortho)       z_depth= VecZDepthOrtho(pt, v1, v2, v3, w_tmp);
675                         else                            z_depth= VecZDepthPersp(pt, v1, v2, v3, w_tmp);
676                         
677                         if (z_depth < z_depth_best) {
678                                 best_face_index = face_index;
679                                 best_side = 0;
680                                 z_depth_best = z_depth;
681                                 copy_v3_v3(w, w_tmp);
682                         }
683                 }
684                 else if (mf->v4) {
685                         v4= ps->screenCoords[mf->v4];
686                         
687                         if (isect_point_tri_v2(pt, v1, v3, v4)) {
688                                 if (ps->is_ortho)       z_depth= VecZDepthOrtho(pt, v1, v3, v4, w_tmp);
689                                 else                            z_depth= VecZDepthPersp(pt, v1, v3, v4, w_tmp);
690
691                                 if (z_depth < z_depth_best) {
692                                         best_face_index = face_index;
693                                         best_side= 1;
694                                         z_depth_best = z_depth;
695                                         copy_v3_v3(w, w_tmp);
696                                 }
697                         }
698                 }
699         }
700         
701         *side = best_side;
702         return best_face_index; /* will be -1 or a valid face */
703 }
704
705 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
706 static void uvco_to_wrapped_pxco(float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
707 {
708         /* use */
709         *x = (float)fmodf(uv[0], 1.0f);
710         *y = (float)fmodf(uv[1], 1.0f);
711         
712         if (*x < 0.0f) *x += 1.0f;
713         if (*y < 0.0f) *y += 1.0f;
714         
715         *x = *x * ibuf_x - 0.5f;
716         *y = *y * ibuf_y - 0.5f;
717 }
718
719 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
720 static int project_paint_PickColor(const ProjPaintState *ps, float pt[2], float *rgba_fp, unsigned char *rgba, const int interp)
721 {
722         float w[3], uv[2];
723         int side;
724         int face_index;
725         MTFace *tf;
726         Image *ima;
727         ImBuf *ibuf;
728         int xi, yi;
729         
730         
731         face_index = project_paint_PickFace(ps, pt, w, &side);
732         
733         if (face_index == -1)
734                 return 0;
735         
736         tf = ps->dm_mtface + face_index;
737         
738         if (side == 0) {
739                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[1], tf->uv[2], w);
740         }
741         else { /* QUAD */
742                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[2], tf->uv[3], w);
743         }
744
745         ima = project_paint_face_image(ps, ps->dm_mtface, face_index);
746         ibuf = ima->ibufs.first; /* we must have got the imbuf before getting here */
747         if (!ibuf) return 0;
748         
749         if (interp) {
750                 float x, y;
751                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
752                 
753                 if (ibuf->rect_float) {
754                         if (rgba_fp) {
755                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
756                         }
757                         else {
758                                 float rgba_tmp_f[4];
759                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
760                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(rgba, rgba_tmp_f);
761                         }
762                 }
763                 else {
764                         if (rgba) {
765                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
766                         }
767                         else {
768                                 unsigned char rgba_tmp[4];
769                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
770                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(rgba_fp, rgba_tmp);
771                         }
772                 }
773         }
774         else {
775                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
776                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
777                 //if (xi<0 || xi>=ibuf->x  ||  yi<0 || yi>=ibuf->y) return 0;
778                 
779                 /* wrap */
780                 xi = ((int)(uv[0]*ibuf->x)) % ibuf->x;
781                 if (xi<0) xi += ibuf->x;
782                 yi = ((int)(uv[1]*ibuf->y)) % ibuf->y;
783                 if (yi<0) yi += ibuf->y;
784                 
785                 
786                 if (rgba) {
787                         if (ibuf->rect_float) {
788                                 float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
789                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(rgba, rgba_tmp_fp);
790                         }
791                         else {
792                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
793                         }
794                 }
795                 
796                 if (rgba_fp) {
797                         if (ibuf->rect_float) {
798                                 copy_v4_v4(rgba_fp, ((float *)ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
799                         }
800                         else {
801                                 char *tmp_ch= ((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
802                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(rgba_fp, tmp_ch);
803                         }
804                 }
805         }
806         return 1;
807 }
808
809 /* Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusuion test)
810  * return...
811  *  0   : no occlusion
812  * -1   : no occlusion but 2D intersection is true (avoid testing the other half of a quad)
813  *  1   : occluded
814  *  2   : occluded with w[3] weights set (need to know in some cases) */
815
816 static int project_paint_occlude_ptv(float pt[3], float v1[4], float v2[4], float v3[4], float w[3], int is_ortho)
817 {
818         /* if all are behind us, return false */
819         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
820                 return 0;
821                 
822         /* do a 2D point in try intersection */
823         if (!isect_point_tri_v2(pt, v1, v2, v3))
824                 return 0; /* we know there is  */
825         
826
827         /* From here on we know there IS an intersection */
828         /* if ALL of the verts are infront of us then we know it intersects ? */
829         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
830                 return 1;
831         }
832         else {
833                 /* we intersect? - find the exact depth at the point of intersection */
834                 /* Is this point is occluded by another face? */
835                 if (is_ortho) {
836                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
837                 }
838                 else {
839                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
840                 }
841         }
842         return -1;
843 }
844
845
846 static int project_paint_occlude_ptv_clip(
847                 const ProjPaintState *ps, const MFace *mf,
848                 float pt[3], float v1[4], float v2[4], float v3[4],
849                 const int side )
850 {
851         float w[3], wco[3];
852         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, ps->is_ortho);
853
854         if (ret <= 0)
855                 return ret;
856
857         if (ret==1) { /* weights not calculated */
858                 if (ps->is_ortho)       barycentric_weights_v2(v1, v2, v3, pt, w);
859                 else                            barycentric_weights_v2_persp(v1, v2, v3, pt, w);
860         }
861
862         /* Test if we're in the clipped area, */
863         if (side)       interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v3].co, ps->dm_mvert[mf->v4].co, w);
864         else            interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
865         
866         if (!ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
867                 return 1;
868         }
869         
870         return -1;
871 }
872
873
874 /* Check if a screenspace location is occluded by any other faces
875  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
876  * and dosn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
877 static int project_bucket_point_occluded(const ProjPaintState *ps, LinkNode *bucketFace, const int orig_face, float pixelScreenCo[4])
878 {
879         MFace *mf;
880         int face_index;
881         int isect_ret;
882         float w[3]; /* not needed when clipping */
883         const short do_clip= ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
884         
885         /* we could return 0 for 1 face buckets, as long as this function assumes
886          * that the point its testing is only every originated from an existing face */
887
888         for (; bucketFace; bucketFace = bucketFace->next) {
889                 face_index = GET_INT_FROM_POINTER(bucketFace->link);
890
891                 if (orig_face != face_index) {
892                         mf = ps->dm_mface + face_index;
893                         if (do_clip)
894                                 isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], 0);
895                         else
896                                 isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], w, ps->is_ortho);
897
898                         /* Note, if isect_ret==-1 then we don't want to test the other side of the quad */
899                         if (isect_ret==0 && mf->v4) {
900                                 if (do_clip)
901                                         isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], 1);
902                                 else
903                                         isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], w, ps->is_ortho);
904                         }
905                         if (isect_ret>=1) {
906                                 /* TODO - we may want to cache the first hit,
907                                  * it is not possible to swap the face order in the list anymore */
908                                 return 1;
909                         }
910                 }
911         }
912         return 0;
913 }
914
915 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
916  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
917 #define ISECT_TRUE 1
918 #define ISECT_TRUE_P1 2
919 #define ISECT_TRUE_P2 3
920 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
921 {
922         float y_diff;
923         
924         if (y_level==p1[1]) { /* are we touching the first point? - no interpolation needed */
925                 *x_isect = p1[0];
926                 return ISECT_TRUE_P1;
927         }
928         if (y_level==p2[1]) { /* are we touching the second point? - no interpolation needed */
929                 *x_isect = p2[0];
930                 return ISECT_TRUE_P2;
931         }
932         
933         y_diff= fabsf(p1[1]-p2[1]); /* yuck, horizontal line, we cant do much here */
934         
935         if (y_diff < 0.000001f) {
936                 *x_isect = (p1[0]+p2[0]) * 0.5f;
937                 return ISECT_TRUE;              
938         }
939         
940         if (p1[1] > y_level && p2[1] < y_level) {
941                 *x_isect = (p2[0]*(p1[1]-y_level) + p1[0]*(y_level-p2[1])) / y_diff;  /*(p1[1]-p2[1]);*/
942                 return ISECT_TRUE;
943         }
944         else if (p1[1] < y_level && p2[1] > y_level) {
945                 *x_isect = (p2[0]*(y_level-p1[1]) + p1[0]*(p2[1]-y_level)) / y_diff;  /*(p2[1]-p1[1]);*/
946                 return ISECT_TRUE;
947         }
948         else {
949                 return 0;
950         }
951 }
952
953 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
954 {
955         float x_diff;
956         
957         if (x_level==p1[0]) { /* are we touching the first point? - no interpolation needed */
958                 *y_isect = p1[1];
959                 return ISECT_TRUE_P1;
960         }
961         if (x_level==p2[0]) { /* are we touching the second point? - no interpolation needed */
962                 *y_isect = p2[1];
963                 return ISECT_TRUE_P2;
964         }
965         
966         x_diff= fabsf(p1[0]-p2[0]); /* yuck, horizontal line, we cant do much here */
967         
968         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
969                 *y_isect = (p1[0]+p2[0]) * 0.5f;
970                 return ISECT_TRUE;              
971         }
972         
973         if (p1[0] > x_level && p2[0] < x_level) {
974                 *y_isect = (p2[1]*(p1[0]-x_level) + p1[1]*(x_level-p2[0])) / x_diff; /*(p1[0]-p2[0]);*/
975                 return ISECT_TRUE;
976         }
977         else if (p1[0] < x_level && p2[0] > x_level) {
978                 *y_isect = (p2[1]*(x_level-p1[0]) + p1[1]*(p2[0]-x_level)) / x_diff; /*(p2[0]-p1[0]);*/
979                 return ISECT_TRUE;
980         }
981         else {
982                 return 0;
983         }
984 }
985
986 /* simple func use for comparing UV locations to check if there are seams.
987  * Its possible this gives incorrect results, when the UVs for 1 face go into the next 
988  * tile, but do not do this for the adjacent face, it could return a false positive.
989  * This is so unlikely that Id not worry about it. */
990 #ifndef PROJ_DEBUG_NOSEAMBLEED
991 static int cmp_uv(const float vec2a[2], const float vec2b[2])
992 {
993         /* if the UV's are not between 0.0 and 1.0 */
994         float xa = (float)fmodf(vec2a[0], 1.0f);
995         float ya = (float)fmodf(vec2a[1], 1.0f);
996         
997         float xb = (float)fmodf(vec2b[0], 1.0f);
998         float yb = (float)fmodf(vec2b[1], 1.0f);        
999         
1000         if (xa < 0.0f) xa += 1.0f;
1001         if (ya < 0.0f) ya += 1.0f;
1002         
1003         if (xb < 0.0f) xb += 1.0f;
1004         if (yb < 0.0f) yb += 1.0f;
1005         
1006         return ((fabsf(xa-xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya-yb) < PROJ_GEOM_TOLERANCE)) ? 1:0;
1007 }
1008 #endif
1009
1010 /* set min_px and max_px to the image space bounds of the UV coords 
1011  * return zero if there is no area in the returned rectangle */
1012 #ifndef PROJ_DEBUG_NOSEAMBLEED
1013 static int pixel_bounds_uv(
1014                 const float uv1[2], const float uv2[2], const float uv3[2], const float uv4[2],
1015                 rcti *bounds_px,
1016                 const int ibuf_x, const int ibuf_y,
1017                 int is_quad
1018 ) {
1019         float min_uv[2], max_uv[2]; /* UV bounds */
1020         
1021         INIT_MINMAX2(min_uv, max_uv);
1022         
1023         DO_MINMAX2(uv1, min_uv, max_uv);
1024         DO_MINMAX2(uv2, min_uv, max_uv);
1025         DO_MINMAX2(uv3, min_uv, max_uv);
1026         if (is_quad)
1027                 DO_MINMAX2(uv4, min_uv, max_uv);
1028         
1029         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
1030         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
1031         
1032         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) +1;
1033         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) +1;
1034         
1035         /*printf("%d %d %d %d \n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
1036         
1037         /* face uses no UV area when quantized to pixels? */
1038         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
1039 }
1040 #endif
1041
1042 static int pixel_bounds_array(float (* uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
1043 {
1044         float min_uv[2], max_uv[2]; /* UV bounds */
1045         
1046         if (tot==0) {
1047                 return 0;
1048         }
1049         
1050         INIT_MINMAX2(min_uv, max_uv);
1051         
1052         while (tot--) {
1053                 DO_MINMAX2((*uv), min_uv, max_uv);
1054                 uv++;
1055         }
1056         
1057         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
1058         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
1059         
1060         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) +1;
1061         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) +1;
1062         
1063         /*printf("%d %d %d %d \n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
1064         
1065         /* face uses no UV area when quantized to pixels? */
1066         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
1067 }
1068
1069 #ifndef PROJ_DEBUG_NOSEAMBLEED
1070
1071 /* This function returns 1 if this face has a seam along the 2 face-vert indices
1072  * 'orig_i1_fidx' and 'orig_i2_fidx' */
1073 static int check_seam(const ProjPaintState *ps, const int orig_face, const int orig_i1_fidx, const int orig_i2_fidx, int *other_face, int *orig_fidx)
1074 {
1075         LinkNode *node;
1076         int face_index;
1077         unsigned int i1, i2;
1078         int i1_fidx = -1, i2_fidx = -1; /* index in face */
1079         MFace *mf;
1080         MTFace *tf;
1081         const MFace *orig_mf = ps->dm_mface + orig_face;  
1082         const MTFace *orig_tf = ps->dm_mtface + orig_face;
1083         
1084         /* vert indices from face vert order indices */
1085         i1 = (*(&orig_mf->v1 + orig_i1_fidx));
1086         i2 = (*(&orig_mf->v1 + orig_i2_fidx));
1087         
1088         for (node = ps->vertFaces[i1]; node; node = node->next) {
1089                 face_index = GET_INT_FROM_POINTER(node->link);
1090
1091                 if (face_index != orig_face) {
1092                         mf = ps->dm_mface + face_index;
1093                         /* could check if the 2 faces images match here,
1094                          * but then there wouldn't be a way to return the opposite face's info */
1095                         
1096                         
1097                         /* We need to know the order of the verts in the adjacent face 
1098                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
1099                         if              (mf->v1==i1)                    i1_fidx = 0;
1100                         else if (mf->v2==i1)                    i1_fidx = 1;
1101                         else if (mf->v3==i1)                    i1_fidx = 2;
1102                         else if (mf->v4 && mf->v4==i1)  i1_fidx = 3;
1103                         
1104                         if              (mf->v1==i2)                    i2_fidx = 0;
1105                         else if (mf->v2==i2)                    i2_fidx = 1;
1106                         else if (mf->v3==i2)                    i2_fidx = 2;
1107                         else if (mf->v4 && mf->v4==i2)  i2_fidx = 3;
1108                         
1109                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
1110                         if (i2_fidx != -1) {
1111                                 Image *tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
1112                                 Image *orig_tpage = project_paint_face_image(ps, ps->dm_mtface, orig_face);
1113
1114                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
1115                                 tf = ps->dm_mtface + face_index;
1116                                 
1117                                 /* set up the other face */
1118                                 *other_face = face_index;
1119                                 *orig_fidx = (i1_fidx < i2_fidx) ? i1_fidx : i2_fidx;
1120                                 
1121                                 /* first test if they have the same image */
1122                                 if (    (orig_tpage == tpage) &&
1123                                                 cmp_uv(orig_tf->uv[orig_i1_fidx], tf->uv[i1_fidx]) &&
1124                                                 cmp_uv(orig_tf->uv[orig_i2_fidx], tf->uv[i2_fidx]) )
1125                                 {
1126                                         // printf("SEAM (NONE)\n");
1127                                         return 0;
1128                                         
1129                                 }
1130                                 else {
1131                                         // printf("SEAM (UV GAP)\n");
1132                                         return 1;
1133                                 }
1134                         }
1135                 }
1136         }
1137         // printf("SEAM (NO FACE)\n");
1138         *other_face = -1;
1139         return 1;
1140 }
1141
1142 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
1143  * since the outset coords are a margin that keep an even distance from the original UV's,
1144  * note that the image aspect is taken into account */
1145 static void uv_image_outset(float (*orig_uv)[2], float (*outset_uv)[2], const float scaler, const int ibuf_x, const int ibuf_y, const int is_quad)
1146 {
1147         float a1, a2, a3, a4=0.0f;
1148         float puv[4][2]; /* pixelspace uv's */
1149         float no1[2], no2[2], no3[2], no4[2]; /* normals */
1150         float dir1[2], dir2[2], dir3[2], dir4[2];
1151         float ibuf_inv[2];
1152
1153         ibuf_inv[0]= 1.0f / (float)ibuf_x;
1154         ibuf_inv[1]= 1.0f / (float)ibuf_y;
1155
1156         /* make UV's in pixel space so we can */
1157         puv[0][0] = orig_uv[0][0] * ibuf_x;
1158         puv[0][1] = orig_uv[0][1] * ibuf_y;
1159         
1160         puv[1][0] = orig_uv[1][0] * ibuf_x;
1161         puv[1][1] = orig_uv[1][1] * ibuf_y;
1162         
1163         puv[2][0] = orig_uv[2][0] * ibuf_x;
1164         puv[2][1] = orig_uv[2][1] * ibuf_y;
1165         
1166         if (is_quad) {
1167                 puv[3][0] = orig_uv[3][0] * ibuf_x;
1168                 puv[3][1] = orig_uv[3][1] * ibuf_y;
1169         }
1170         
1171         /* face edge directions */
1172         sub_v2_v2v2(dir1, puv[1], puv[0]);
1173         sub_v2_v2v2(dir2, puv[2], puv[1]);
1174         normalize_v2(dir1);
1175         normalize_v2(dir2);
1176         
1177         if (is_quad) {
1178                 sub_v2_v2v2(dir3, puv[3], puv[2]);
1179                 sub_v2_v2v2(dir4, puv[0], puv[3]);
1180                 normalize_v2(dir3);
1181                 normalize_v2(dir4);
1182         }
1183         else {
1184                 sub_v2_v2v2(dir3, puv[0], puv[2]);
1185                 normalize_v2(dir3);
1186         }
1187
1188         /* TODO - angle_normalized_v2v2(...) * (M_PI/180.0f)
1189          * This is incorrect. Its already given radians but without it wont work.
1190          * need to look into a fix - campbell */
1191         if (is_quad) {
1192                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir4, dir1) * ((float)M_PI/180.0f));
1193                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI/180.0f));
1194                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI/180.0f));
1195                 a4 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir4) * ((float)M_PI/180.0f));
1196         }
1197         else {
1198                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir1) * ((float)M_PI/180.0f));
1199                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI/180.0f));
1200                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI/180.0f));
1201         }
1202         
1203         if (is_quad) {
1204                 sub_v2_v2v2(no1, dir4, dir1);
1205                 sub_v2_v2v2(no2, dir1, dir2);
1206                 sub_v2_v2v2(no3, dir2, dir3);
1207                 sub_v2_v2v2(no4, dir3, dir4);
1208                 normalize_v2(no1);
1209                 normalize_v2(no2);
1210                 normalize_v2(no3);
1211                 normalize_v2(no4);
1212                 mul_v2_fl(no1, a1*scaler);
1213                 mul_v2_fl(no2, a2*scaler);
1214                 mul_v2_fl(no3, a3*scaler);
1215                 mul_v2_fl(no4, a4*scaler);
1216                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1217                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1218                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1219                 add_v2_v2v2(outset_uv[3], puv[3], no4);
1220                 mul_v2_v2(outset_uv[0], ibuf_inv);
1221                 mul_v2_v2(outset_uv[1], ibuf_inv);
1222                 mul_v2_v2(outset_uv[2], ibuf_inv);
1223                 mul_v2_v2(outset_uv[3], ibuf_inv);
1224         }
1225         else {
1226                 sub_v2_v2v2(no1, dir3, dir1);
1227                 sub_v2_v2v2(no2, dir1, dir2);
1228                 sub_v2_v2v2(no3, dir2, dir3);
1229                 normalize_v2(no1);
1230                 normalize_v2(no2);
1231                 normalize_v2(no3);
1232                 mul_v2_fl(no1, a1*scaler);
1233                 mul_v2_fl(no2, a2*scaler);
1234                 mul_v2_fl(no3, a3*scaler);
1235                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1236                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1237                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1238
1239                 mul_v2_v2(outset_uv[0], ibuf_inv);
1240                 mul_v2_v2(outset_uv[1], ibuf_inv);
1241                 mul_v2_v2(outset_uv[2], ibuf_inv);
1242         }
1243 }
1244
1245 /* 
1246  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1247  * 1<<i - where i is (0-3) 
1248  * 
1249  * If we're multithreadng, make sure threads are locked when this is called
1250  */
1251 static void project_face_seams_init(const ProjPaintState *ps, const int face_index, const int is_quad)
1252 {
1253         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1254         int fidx1 = is_quad ? 3 : 2;
1255         int fidx2 = 0; /* next fidx in the face (0,1,2,3) -> (1,2,3,0) or (0,1,2) -> (1,2,0) for a tri */
1256         
1257         do {
1258                 if ((ps->faceSeamFlags[face_index] & (1<<fidx1|16<<fidx1)) == 0) {
1259                         if (check_seam(ps, face_index, fidx1, fidx2, &other_face, &other_fidx)) {
1260                                 ps->faceSeamFlags[face_index] |= 1<<fidx1;
1261                                 if (other_face != -1)
1262                                         ps->faceSeamFlags[other_face] |= 1<<other_fidx;
1263                         }
1264                         else {
1265                                 ps->faceSeamFlags[face_index] |= 16<<fidx1;
1266                                 if (other_face != -1)
1267                                         ps->faceSeamFlags[other_face] |= 16<<other_fidx; /* second 4 bits for disabled */
1268                         }
1269                 }
1270                 
1271                 fidx2 = fidx1;
1272         } while (fidx1--);
1273 }
1274 #endif // PROJ_DEBUG_NOSEAMBLEED
1275
1276
1277 /* Converts a UV location to a 3D screenspace location
1278  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1279  * 
1280  * This is used for finding a pixels location in screenspace for painting */
1281 static void screen_px_from_ortho(
1282                 float uv[2],
1283                 float v1co[3], float v2co[3], float v3co[3], /* Screenspace coords */
1284                 float uv1co[2], float uv2co[2], float uv3co[2],
1285                 float pixelScreenCo[4],
1286                 float w[3])
1287 {
1288         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1289         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1290 }
1291
1292 /* same as screen_px_from_ortho except we need to take into account
1293  * the perspective W coord for each vert */
1294 static void screen_px_from_persp(
1295                 float uv[2],
1296                 float v1co[4], float v2co[4], float v3co[4], /* screenspace coords */
1297                 float uv1co[2], float uv2co[2], float uv3co[2],
1298                 float pixelScreenCo[4],
1299                 float w[3])
1300 {
1301
1302         float wtot_inv, wtot;
1303         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1304         
1305         /* re-weight from the 4th coord of each screen vert */
1306         w[0] *= v1co[3];
1307         w[1] *= v2co[3];
1308         w[2] *= v3co[3];
1309         
1310         wtot = w[0]+w[1]+w[2];
1311         
1312         if (wtot > 0.0f) {
1313                 wtot_inv = 1.0f / wtot;
1314                 w[0] *= wtot_inv;
1315                 w[1] *= wtot_inv;
1316                 w[2] *= wtot_inv;
1317         }
1318         else {
1319                 w[0] = w[1] = w[2] = 1.0f/3.0f; /* dummy values for zero area face */
1320         }
1321         /* done re-weighting */
1322         
1323         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1324 }
1325
1326 static void project_face_pixel(const MTFace *tf_other, ImBuf *ibuf_other, const float w[3], int side, unsigned char rgba_ub[4], float rgba_f[4])
1327 {
1328         float *uvCo1, *uvCo2, *uvCo3;
1329         float uv_other[2], x, y;
1330         
1331         uvCo1 =  (float *)tf_other->uv[0];
1332         if (side==1) {
1333                 uvCo2 =  (float *)tf_other->uv[2];
1334                 uvCo3 =  (float *)tf_other->uv[3];
1335         }
1336         else {
1337                 uvCo2 =  (float *)tf_other->uv[1];
1338                 uvCo3 =  (float *)tf_other->uv[2];
1339         }
1340         
1341         interp_v2_v2v2v2(uv_other, uvCo1, uvCo2, uvCo3, (float*)w);
1342         
1343         /* use */
1344         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1345         
1346         
1347         if (ibuf_other->rect_float) { /* from float to float */
1348                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1349         }
1350         else { /* from char to float */
1351                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1352         }
1353                 
1354 }
1355
1356 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1357 static float project_paint_uvpixel_mask(
1358                 const ProjPaintState *ps,
1359                 const int face_index,
1360                 const int side,
1361                 const float w[3])
1362 {
1363         float mask;
1364         
1365         /* Image Mask */
1366         if (ps->do_layer_stencil) {
1367                 /* another UV maps image is masking this one's */
1368                 ImBuf *ibuf_other;
1369                 Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_stencil, face_index);
1370                 const MTFace *tf_other = ps->dm_mtface_stencil + face_index;
1371                 
1372                 if (other_tpage && (ibuf_other = BKE_image_get_ibuf(other_tpage, NULL))) {
1373                         /* BKE_image_get_ibuf - TODO - this may be slow */
1374                         unsigned char rgba_ub[4];
1375                         float rgba_f[4];
1376                         
1377                         project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, rgba_f);
1378                         
1379                         if (ibuf_other->rect_float) { /* from float to float */
1380                                 mask = ((rgba_f[0]+rgba_f[1]+rgba_f[2])/3.0f) * rgba_f[3];
1381                         }
1382                         else { /* from char to float */
1383                                 mask = ((rgba_ub[0]+rgba_ub[1]+rgba_ub[2])/(256*3.0f)) * (rgba_ub[3]/256.0f);
1384                         }
1385                         
1386                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1387                                 mask = (1.0f - mask);
1388
1389                         if (mask == 0.0f) {
1390                                 return 0.0f;
1391                         }
1392                 }
1393                 else {
1394                         return 0.0f;
1395                 }
1396         }
1397         else {
1398                 mask = 1.0f;
1399         }
1400         
1401         /* calculate mask */
1402         if (ps->do_mask_normal) {
1403                 MFace *mf = ps->dm_mface + face_index;
1404                 short *no1, *no2, *no3;
1405                 float no[3], angle;
1406                 no1 = ps->dm_mvert[mf->v1].no;
1407                 if (side==1) {
1408                         no2 = ps->dm_mvert[mf->v3].no;
1409                         no3 = ps->dm_mvert[mf->v4].no;
1410                 }
1411                 else {
1412                         no2 = ps->dm_mvert[mf->v2].no;
1413                         no3 = ps->dm_mvert[mf->v3].no;
1414                 }
1415                 
1416                 no[0] = w[0]*no1[0] + w[1]*no2[0] + w[2]*no3[0];
1417                 no[1] = w[0]*no1[1] + w[1]*no2[1] + w[2]*no3[1];
1418                 no[2] = w[0]*no1[2] + w[1]*no2[2] + w[2]*no3[2];
1419                 normalize_v3(no);
1420                 
1421                 /* now we can use the normal as a mask */
1422                 if (ps->is_ortho) {
1423                         angle = angle_normalized_v3v3((float *)ps->viewDir, no);
1424                 }
1425                 else {
1426                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1427                         float viewDirPersp[3];
1428                         float *co1, *co2, *co3;
1429                         co1 = ps->dm_mvert[mf->v1].co;
1430                         if (side==1) {
1431                                 co2 = ps->dm_mvert[mf->v3].co;
1432                                 co3 = ps->dm_mvert[mf->v4].co;
1433                         }
1434                         else {
1435                                 co2 = ps->dm_mvert[mf->v2].co;
1436                                 co3 = ps->dm_mvert[mf->v3].co;
1437                         }
1438
1439                         /* Get the direction from the viewPoint to the pixel and normalize */
1440                         viewDirPersp[0] = (ps->viewPos[0] - (w[0]*co1[0] + w[1]*co2[0] + w[2]*co3[0]));
1441                         viewDirPersp[1] = (ps->viewPos[1] - (w[0]*co1[1] + w[1]*co2[1] + w[2]*co3[1]));
1442                         viewDirPersp[2] = (ps->viewPos[2] - (w[0]*co1[2] + w[1]*co2[2] + w[2]*co3[2]));
1443                         normalize_v3(viewDirPersp);
1444                         
1445                         angle = angle_normalized_v3v3(viewDirPersp, no);
1446                 }
1447                 
1448                 if (angle >= ps->normal_angle) {
1449                         return 0.0f; /* outsize the normal limit*/
1450                 }
1451                 else if (angle > ps->normal_angle_inner) {
1452                         mask *= (ps->normal_angle - angle) / ps->normal_angle_range;
1453                 } /* otherwise no mask normal is needed, were within the limit */
1454         }
1455         
1456         // This only works when the opacity dosnt change while painting, stylus pressure messes with this
1457         // so don't use it.
1458         // if (ps->is_airbrush==0) mask *= brush_alpha(ps->brush);
1459         
1460         return mask;
1461 }
1462
1463 /* run this function when we know a bucket's, face's pixel can be initialized,
1464  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1465 static ProjPixel *project_paint_uvpixel_init(
1466                 const ProjPaintState *ps,
1467                 MemArena *arena,
1468                 const ImBuf *ibuf,
1469                 short x_px, short y_px,
1470                 const float mask,
1471                 const int face_index,
1472                 const int image_index,
1473                 const float pixelScreenCo[4],
1474                 const int side,
1475                 const float w[3])
1476 {
1477         ProjPixel *projPixel;
1478         short size;
1479         
1480         /* wrap pixel location */
1481         x_px = x_px % ibuf->x;
1482         if (x_px<0) x_px += ibuf->x;
1483         y_px = y_px % ibuf->y;
1484         if (y_px<0) y_px += ibuf->y;
1485         
1486         if (ps->tool==PAINT_TOOL_CLONE) {
1487                 size = sizeof(ProjPixelClone);
1488         }
1489         else if (ps->tool==PAINT_TOOL_SMEAR) {
1490                 size = sizeof(ProjPixelClone);
1491         }
1492         else {
1493                 size = sizeof(ProjPixel);
1494         }
1495         
1496         projPixel = (ProjPixel *)BLI_memarena_alloc(arena, size);
1497         //memset(projPixel, 0, size);
1498         
1499         if (ibuf->rect_float) {
1500                 projPixel->pixel.f_pt = (float *)ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1501                 projPixel->origColor.f[0] = projPixel->newColor.f[0] = projPixel->pixel.f_pt[0];  
1502                 projPixel->origColor.f[1] = projPixel->newColor.f[1] = projPixel->pixel.f_pt[1];  
1503                 projPixel->origColor.f[2] = projPixel->newColor.f[2] = projPixel->pixel.f_pt[2];  
1504                 projPixel->origColor.f[3] = projPixel->newColor.f[3] = projPixel->pixel.f_pt[3];  
1505         }
1506         else {
1507                 projPixel->pixel.ch_pt = ((unsigned char *)ibuf->rect + ((x_px + y_px * ibuf->x) * 4));
1508                 projPixel->origColor.uint = projPixel->newColor.uint = *projPixel->pixel.uint_pt;
1509         }
1510         
1511         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1512         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1513         
1514         projPixel->x_px = x_px;
1515         projPixel->y_px = y_px;
1516         
1517         projPixel->mask = (unsigned short)(mask * 65535);
1518         projPixel->mask_max = 0;
1519         
1520         /* which bounding box cell are we in?, needed for undo */
1521         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1522                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1523         
1524         /* done with view3d_project_float inline */
1525         if (ps->tool==PAINT_TOOL_CLONE) {
1526                 if (ps->dm_mtface_clone) {
1527                         ImBuf *ibuf_other;
1528                         Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_clone, face_index);
1529                         const MTFace *tf_other = ps->dm_mtface_clone + face_index;
1530                         
1531                         if (other_tpage && (ibuf_other = BKE_image_get_ibuf(other_tpage, NULL))) {
1532                                 /* BKE_image_get_ibuf - TODO - this may be slow */
1533                                 
1534                                 if (ibuf->rect_float) {
1535                                         if (ibuf_other->rect_float) { /* from float to float */
1536                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1537                                         }
1538                                         else { /* from char to float */
1539                                                 unsigned char rgba_ub[4];
1540                                                 project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, NULL);
1541                                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(((ProjPixelClone *)projPixel)->clonepx.f, rgba_ub);
1542                                         }
1543                                 }
1544                                 else {
1545                                         if (ibuf_other->rect_float) { /* float to char */
1546                                                 float rgba[4];
1547                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, rgba);
1548                                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(((ProjPixelClone *)projPixel)->clonepx.ch, rgba)
1549                                         }
1550                                         else { /* char to char */
1551                                                 project_face_pixel(tf_other, ibuf_other, w, side, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1552                                         }
1553                                 }
1554                         }
1555                         else {
1556                                 if (ibuf->rect_float) {
1557                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1558                                 }
1559                                 else {
1560                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1561                                 }
1562                         }
1563                         
1564                 }
1565                 else {
1566                         float co[2];
1567                         sub_v2_v2v2(co, projPixel->projCoSS, (float *)ps->cloneOffset);
1568                         
1569                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1570                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1571                         if (ibuf->rect_float) {
1572                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1573                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1574                                 }
1575                         }
1576                         else {
1577                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1578                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1579                                 }
1580                         }
1581                 }
1582         }
1583         
1584 #ifdef PROJ_DEBUG_PAINT
1585         if (ibuf->rect_float)   projPixel->pixel.f_pt[0] = 0;
1586         else                                    projPixel->pixel.ch_pt[0] = 0;
1587 #endif
1588         projPixel->image_index = image_index;
1589         
1590         return projPixel;
1591 }
1592
1593 static int line_clip_rect2f(
1594                 rctf *rect,
1595                 const float l1[2], const float l2[2],
1596                 float l1_clip[2], float l2_clip[2])
1597 {
1598         /* first account for horizontal, then vertical lines */
1599         /* horiz */
1600         if (fabsf(l1[1]-l2[1]) < PROJ_GEOM_TOLERANCE) {
1601                 /* is the line out of range on its Y axis? */
1602                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1603                         return 0;
1604                 }
1605                 /* line is out of range on its X axis */
1606                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1607                         return 0;
1608                 }
1609                 
1610                 
1611                 if (fabsf(l1[0]-l2[0]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1612                         if (BLI_in_rctf(rect, l1[0], l1[1])) {
1613                                 copy_v2_v2(l1_clip, l1);
1614                                 copy_v2_v2(l2_clip, l2);
1615                                 return 1;
1616                         }
1617                         else {
1618                                 return 0;
1619                         }
1620                 }
1621                 
1622                 copy_v2_v2(l1_clip, l1);
1623                 copy_v2_v2(l2_clip, l2);
1624                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1625                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1626                 return 1;
1627         }
1628         else if (fabsf(l1[0]-l2[0]) < PROJ_GEOM_TOLERANCE) {
1629                 /* is the line out of range on its X axis? */
1630                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1631                         return 0;
1632                 }
1633                 
1634                 /* line is out of range on its Y axis */
1635                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1636                         return 0;
1637                 }
1638                 
1639                 if (fabsf(l1[1]-l2[1]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1640                         if (BLI_in_rctf(rect, l1[0], l1[1])) {
1641                                 copy_v2_v2(l1_clip, l1);
1642                                 copy_v2_v2(l2_clip, l2);
1643                                 return 1;
1644                         }
1645                         else {
1646                                 return 0;
1647                         }
1648                 }
1649                 
1650                 copy_v2_v2(l1_clip, l1);
1651                 copy_v2_v2(l2_clip, l2);
1652                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1653                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1654                 return 1;
1655         }
1656         else {
1657                 float isect;
1658                 short ok1 = 0;
1659                 short ok2 = 0;
1660                 
1661                 /* Done with vertical lines */
1662                 
1663                 /* are either of the points inside the rectangle ? */
1664                 if (BLI_in_rctf(rect, l1[0], l1[1])) {
1665                         copy_v2_v2(l1_clip, l1);
1666                         ok1 = 1;
1667                 }
1668                 
1669                 if (BLI_in_rctf(rect, l2[0], l2[1])) {
1670                         copy_v2_v2(l2_clip, l2);
1671                         ok2 = 1;
1672                 }
1673                 
1674                 /* line inside rect */
1675                 if (ok1 && ok2) return 1;
1676                 
1677                 /* top/bottom */
1678                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1679                         if (l1[1] < l2[1]) { /* line 1 is outside */
1680                                 l1_clip[0] = isect;
1681                                 l1_clip[1] = rect->ymin;
1682                                 ok1 = 1;
1683                         }
1684                         else {
1685                                 l2_clip[0] = isect;
1686                                 l2_clip[1] = rect->ymin;
1687                                 ok2 = 2;
1688                         }
1689                 }
1690                 
1691                 if (ok1 && ok2) return 1;
1692                 
1693                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1694                         if (l1[1] > l2[1]) { /* line 1 is outside */
1695                                 l1_clip[0] = isect;
1696                                 l1_clip[1] = rect->ymax;
1697                                 ok1 = 1;
1698                         }
1699                         else {
1700                                 l2_clip[0] = isect;
1701                                 l2_clip[1] = rect->ymax;
1702                                 ok2 = 2;
1703                         }
1704                 }
1705                 
1706                 if (ok1 && ok2) return 1;
1707                 
1708                 /* left/right */
1709                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1710                         if (l1[0] < l2[0]) { /* line 1 is outside */
1711                                 l1_clip[0] = rect->xmin;
1712                                 l1_clip[1] = isect;
1713                                 ok1 = 1;
1714                         }
1715                         else {
1716                                 l2_clip[0] = rect->xmin;
1717                                 l2_clip[1] = isect;
1718                                 ok2 = 2;
1719                         }
1720                 }
1721         
1722                 if (ok1 && ok2) return 1;
1723                 
1724                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1725                         if (l1[0] > l2[0]) { /* line 1 is outside */
1726                                 l1_clip[0] = rect->xmax;
1727                                 l1_clip[1] = isect;
1728                                 ok1 = 1;
1729                         }
1730                         else {
1731                                 l2_clip[0] = rect->xmax;
1732                                 l2_clip[1] = isect;
1733                                 ok2 = 2;
1734                         }
1735                 }
1736                 
1737                 if (ok1 && ok2) {
1738                         return 1;
1739                 }
1740                 else {
1741                         return 0;
1742                 }
1743         }
1744 }
1745
1746
1747
1748 /* scale the quad & tri about its center
1749  * scaling by PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1750  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces */
1751 #ifndef PROJ_DEBUG_NOSEAMBLEED
1752 static void scale_quad(float insetCos[4][3], float *origCos[4], const float inset)
1753 {
1754         float cent[3];
1755         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0] + origCos[3][0]) / 4.0f;
1756         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1] + origCos[3][1]) / 4.0f;
1757         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2] + origCos[3][2]) / 4.0f;
1758         
1759         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1760         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1761         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1762         sub_v3_v3v3(insetCos[3], origCos[3], cent);
1763         
1764         mul_v3_fl(insetCos[0], inset);
1765         mul_v3_fl(insetCos[1], inset);
1766         mul_v3_fl(insetCos[2], inset);
1767         mul_v3_fl(insetCos[3], inset);
1768         
1769         add_v3_v3(insetCos[0], cent);
1770         add_v3_v3(insetCos[1], cent);
1771         add_v3_v3(insetCos[2], cent);
1772         add_v3_v3(insetCos[3], cent);
1773 }
1774
1775
1776 static void scale_tri(float insetCos[4][3], float *origCos[4], const float inset)
1777 {
1778         float cent[3];
1779         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) / 3.0f;
1780         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) / 3.0f;
1781         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) / 3.0f;
1782         
1783         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1784         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1785         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1786         
1787         mul_v3_fl(insetCos[0], inset);
1788         mul_v3_fl(insetCos[1], inset);
1789         mul_v3_fl(insetCos[2], inset);
1790         
1791         add_v3_v3(insetCos[0], cent);
1792         add_v3_v3(insetCos[1], cent);
1793         add_v3_v3(insetCos[2], cent);
1794 }
1795 #endif //PROJ_DEBUG_NOSEAMBLEED
1796
1797 static float len_squared_v2v2_alt(const float *v1, const float v2_1, const float v2_2)
1798 {
1799         float x, y;
1800
1801         x = v1[0]-v2_1;
1802         y = v1[1]-v2_2;
1803         return x*x+y*y;
1804 }
1805
1806 /* note, use a squared value so we can use len_squared_v2v2
1807  * be sure that you have done a bounds check first or this may fail */
1808 /* only give bucket_bounds as an arg because we need it elsewhere */
1809 static int project_bucket_isect_circle(const float cent[2], const float radius_squared, rctf *bucket_bounds)
1810 {
1811          
1812         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect 
1813          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1814          * this is even less work then an intersection test
1815          */
1816 #if 0
1817         if (BLI_in_rctf(bucket_bounds, cent[0], cent[1]))
1818                 return 1;
1819 #endif
1820         
1821         if ( (bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1822              (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]) )
1823         {
1824                 return 1;
1825         }
1826         
1827         /* out of bounds left */
1828         if (cent[0] < bucket_bounds->xmin) {
1829                 /* lower left out of radius test */
1830                 if (cent[1] < bucket_bounds->ymin) {
1831                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1832                 } 
1833                 /* top left test */
1834                 else if (cent[1] > bucket_bounds->ymax) {
1835                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1836                 }
1837         }
1838         else if (cent[0] > bucket_bounds->xmax) {
1839                 /* lower right out of radius test */
1840                 if (cent[1] < bucket_bounds->ymin) {
1841                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1842                 } 
1843                 /* top right test */
1844                 else if (cent[1] > bucket_bounds->ymax) {
1845                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1846                 }
1847         }
1848         
1849         return 0;
1850 }
1851
1852
1853
1854 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1855  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1856  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1857  * (viewed from the side)
1858  * 
1859  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1860  * funcs that only account for points inside the triangle.
1861  * however switching back to this for ortho is always an option */
1862
1863 static void rect_to_uvspace_ortho(
1864                 rctf *bucket_bounds,
1865                 float *v1coSS, float *v2coSS, float *v3coSS,
1866                 float *uv1co, float *uv2co, float *uv3co,
1867                 float bucket_bounds_uv[4][2],
1868                 const int flip)
1869 {
1870         float uv[2];
1871         float w[3];
1872         
1873         /* get the UV space bounding box */
1874         uv[0] = bucket_bounds->xmax;
1875         uv[1] = bucket_bounds->ymin;
1876         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1877         interp_v2_v2v2v2(bucket_bounds_uv[flip?3:0], uv1co, uv2co, uv3co, w);
1878
1879         //uv[0] = bucket_bounds->xmax; // set above
1880         uv[1] = bucket_bounds->ymax;
1881         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1882         interp_v2_v2v2v2(bucket_bounds_uv[flip?2:1], uv1co, uv2co, uv3co, w);
1883
1884         uv[0] = bucket_bounds->xmin;
1885         //uv[1] = bucket_bounds->ymax; // set above
1886         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1887         interp_v2_v2v2v2(bucket_bounds_uv[flip?1:2], uv1co, uv2co, uv3co, w);
1888
1889         //uv[0] = bucket_bounds->xmin; // set above
1890         uv[1] = bucket_bounds->ymin;
1891         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1892         interp_v2_v2v2v2(bucket_bounds_uv[flip?0:3], uv1co, uv2co, uv3co, w);
1893 }
1894
1895 /* same as above but use barycentric_weights_v2_persp */
1896 static void rect_to_uvspace_persp(
1897                 rctf *bucket_bounds,
1898                 float *v1coSS, float *v2coSS, float *v3coSS,
1899                 float *uv1co, float *uv2co, float *uv3co,
1900                 float bucket_bounds_uv[4][2],
1901                 const int flip
1902         )
1903 {
1904         float uv[2];
1905         float w[3];
1906         
1907         /* get the UV space bounding box */
1908         uv[0] = bucket_bounds->xmax;
1909         uv[1] = bucket_bounds->ymin;
1910         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1911         interp_v2_v2v2v2(bucket_bounds_uv[flip?3:0], uv1co, uv2co, uv3co, w);
1912
1913         //uv[0] = bucket_bounds->xmax; // set above
1914         uv[1] = bucket_bounds->ymax;
1915         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1916         interp_v2_v2v2v2(bucket_bounds_uv[flip?2:1], uv1co, uv2co, uv3co, w);
1917
1918         uv[0] = bucket_bounds->xmin;
1919         //uv[1] = bucket_bounds->ymax; // set above
1920         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1921         interp_v2_v2v2v2(bucket_bounds_uv[flip?1:2], uv1co, uv2co, uv3co, w);
1922
1923         //uv[0] = bucket_bounds->xmin; // set above
1924         uv[1] = bucket_bounds->ymin;
1925         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1926         interp_v2_v2v2v2(bucket_bounds_uv[flip?0:3], uv1co, uv2co, uv3co, w);
1927 }
1928
1929 /* This works as we need it to but we can save a few steps and not use it */
1930
1931 #if 0
1932 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
1933 {
1934         float v1[2], v2[2];
1935         
1936         v1[0] = p1[0]-p2[0];    v1[1] = p1[1]-p2[1];
1937         v2[0] = p3[0]-p2[0];    v2[1] = p3[1]-p2[1];
1938         
1939         return -atan2(v1[0]*v2[1] - v1[1]*v2[0], v1[0]*v2[0]+v1[1]*v2[1]);
1940 }
1941 #endif
1942
1943 #define ISECT_1 (1)
1944 #define ISECT_2 (1<<1)
1945 #define ISECT_3 (1<<2)
1946 #define ISECT_4 (1<<3)
1947 #define ISECT_ALL3 ((1<<3)-1)
1948 #define ISECT_ALL4 ((1<<4)-1)
1949
1950 /* limit must be a fraction over 1.0f */
1951 static int IsectPT2Df_limit(float pt[2], float v1[2], float v2[2], float v3[2], float limit)
1952 {
1953         return ((area_tri_v2(pt,v1,v2) + area_tri_v2(pt,v2,v3) + area_tri_v2(pt,v3,v1)) / (area_tri_v2(v1,v2,v3))) < limit;
1954 }
1955
1956 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
1957  * so we have the clipped UV's to do pixel intersection tests with 
1958  * */
1959 static int float_z_sort_flip(const void *p1, const void *p2)
1960 {
1961         return (((float *)p1)[2] < ((float *)p2)[2] ? 1:-1);
1962 }
1963
1964 static int float_z_sort(const void *p1, const void *p2)
1965 {
1966         return (((float *)p1)[2] < ((float *)p2)[2] ?-1:1);
1967 }
1968
1969 static void project_bucket_clip_face(
1970                 const int is_ortho,
1971                 rctf *bucket_bounds,
1972                 float *v1coSS, float *v2coSS, float *v3coSS,
1973                 float *uv1co, float *uv2co, float *uv3co,
1974                 float bucket_bounds_uv[8][2],
1975                 int *tot)
1976 {
1977         int inside_bucket_flag = 0;
1978         int inside_face_flag = 0;
1979         const int flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
1980         
1981         float bucket_bounds_ss[4][2];
1982
1983         /* get the UV space bounding box */
1984         inside_bucket_flag |= BLI_in_rctf(bucket_bounds, v1coSS[0], v1coSS[1]);
1985         inside_bucket_flag |= BLI_in_rctf(bucket_bounds, v2coSS[0], v2coSS[1])          << 1;
1986         inside_bucket_flag |= BLI_in_rctf(bucket_bounds, v3coSS[0], v3coSS[1])          << 2;
1987         
1988         if (inside_bucket_flag == ISECT_ALL3) {
1989                 /* all screenspace points are inside the bucket bounding box, this means we don't need to clip and can simply return the UVs */
1990                 if (flip) { /* facing the back? */
1991                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
1992                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1993                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
1994                 }
1995                 else {
1996                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
1997                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1998                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
1999                 }
2000                 
2001                 *tot = 3; 
2002                 return;
2003         }
2004         
2005         /* get the UV space bounding box */
2006         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
2007         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
2008         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
2009         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1+PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
2010         
2011         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
2012         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
2013         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1+PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
2014
2015         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
2016         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
2017         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1+PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
2018
2019         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
2020         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
2021         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1+PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
2022         
2023         if (inside_face_flag == ISECT_ALL4) {
2024                 /* bucket is totally inside the screenspace face, we can safely use weights */
2025                 
2026                 if (is_ortho)   rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2027                 else                    rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2028                 
2029                 *tot = 4;
2030                 return;
2031         }
2032         else {
2033                 /* The Complicated Case! 
2034                  * 
2035                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
2036                  * 
2037                  * we need to make a convex polyline from the intersection between the screenspace face
2038                  * and the bucket bounds.
2039                  * 
2040                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
2041                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
2042                  * do a correct clipping on both shapes. */
2043                 
2044                 
2045                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
2046                 
2047                 
2048                 
2049                 /* Maximum possible 6 intersections when using a rectangle and triangle */
2050                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
2051                 float v1_clipSS[2], v2_clipSS[2];
2052                 float w[3];
2053                 
2054                 /* calc center*/
2055                 float cent[2] = {0.0f, 0.0f};
2056                 /*float up[2] = {0.0f, 1.0f};*/
2057                 int i;
2058                 short doubles;
2059                 
2060                 (*tot) = 0;
2061                 
2062                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
2063                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
2064                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
2065                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
2066                 
2067                 if (inside_bucket_flag & ISECT_1) {     copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
2068                 if (inside_bucket_flag & ISECT_2) {     copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
2069                 if (inside_bucket_flag & ISECT_3) {     copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
2070                 
2071                 if ((inside_bucket_flag & (ISECT_1|ISECT_2)) != (ISECT_1|ISECT_2)) {
2072                         if (line_clip_rect2f(bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
2073                                 if ((inside_bucket_flag & ISECT_1)==0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2074                                 if ((inside_bucket_flag & ISECT_2)==0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2075                         }
2076                 }
2077                 
2078                 if ((inside_bucket_flag & (ISECT_2|ISECT_3)) != (ISECT_2|ISECT_3)) {
2079                         if (line_clip_rect2f(bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
2080                                 if ((inside_bucket_flag & ISECT_2)==0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2081                                 if ((inside_bucket_flag & ISECT_3)==0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2082                         }
2083                 }       
2084                 
2085                 if ((inside_bucket_flag & (ISECT_3|ISECT_1)) != (ISECT_3|ISECT_1)) {
2086                         if (line_clip_rect2f(bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
2087                                 if ((inside_bucket_flag & ISECT_3)==0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2088                                 if ((inside_bucket_flag & ISECT_1)==0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2089                         }
2090                 }
2091                 
2092                 
2093                 if ((*tot) < 3) { /* no intersections to speak of */
2094                         *tot = 0;
2095                         return;
2096                 }
2097         
2098                 /* now we have all points we need, collect their angles and sort them clockwise */
2099                 
2100                 for (i=0; i<(*tot); i++) {
2101                         cent[0] += isectVCosSS[i][0];
2102                         cent[1] += isectVCosSS[i][1];
2103                 }
2104                 cent[0] = cent[0] / (float)(*tot);
2105                 cent[1] = cent[1] / (float)(*tot);
2106                 
2107                 
2108                 
2109                 /* Collect angles for every point around the center point */
2110
2111                 
2112 #if 0   /* uses a few more cycles then the above loop */
2113                 for (i=0; i<(*tot); i++) {
2114                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
2115                 }
2116 #endif
2117
2118                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
2119                 v1_clipSS[1] = cent[1] + 1.0f;
2120                 
2121                 for (i=0; i<(*tot); i++) {
2122                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2123                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2124                         isectVCosSS[i][2] = atan2f(v1_clipSS[0]*v2_clipSS[1] - v1_clipSS[1]*v2_clipSS[0], v1_clipSS[0]*v2_clipSS[0]+v1_clipSS[1]*v2_clipSS[1]); 
2125                 }
2126                 
2127                 if (flip)       qsort(isectVCosSS, *tot, sizeof(float)*3, float_z_sort_flip);
2128                 else            qsort(isectVCosSS, *tot, sizeof(float)*3, float_z_sort);
2129                 
2130                 /* remove doubles */
2131                 /* first/last check */
2132                 if (fabsf(isectVCosSS[0][0]-isectVCosSS[(*tot)-1][0]) < PROJ_GEOM_TOLERANCE &&  fabsf(isectVCosSS[0][1]-isectVCosSS[(*tot)-1][1]) < PROJ_GEOM_TOLERANCE) {
2133                         (*tot)--;
2134                 }
2135                 
2136                 /* its possible there is only a few left after remove doubles */
2137                 if ((*tot) < 3) {
2138                         // printf("removed too many doubles A\n");
2139                         *tot = 0;
2140                         return;
2141                 }
2142                 
2143                 doubles = TRUE;
2144                 while (doubles==TRUE) {
2145                         doubles = FALSE;
2146                         for (i=1; i<(*tot); i++) {
2147                                 if (fabsf(isectVCosSS[i-1][0]-isectVCosSS[i][0]) < PROJ_GEOM_TOLERANCE &&
2148                                         fabsf(isectVCosSS[i-1][1]-isectVCosSS[i][1]) < PROJ_GEOM_TOLERANCE)
2149                                 {
2150                                         int j;
2151                                         for (j=i+1; j<(*tot); j++) {
2152                                                 isectVCosSS[j-1][0] = isectVCosSS[j][0]; 
2153                                                 isectVCosSS[j-1][1] = isectVCosSS[j][1]; 
2154                                         }
2155                                         doubles = TRUE; /* keep looking for more doubles */
2156                                         (*tot)--;
2157                                 }
2158                         }
2159                 }
2160                 
2161                 /* its possible there is only a few left after remove doubles */
2162                 if ((*tot) < 3) {
2163                         // printf("removed too many doubles B\n");
2164                         *tot = 0;
2165                         return;
2166                 }
2167                 
2168                 
2169                 if (is_ortho) {
2170                         for (i=0; i<(*tot); i++) {
2171                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2172                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2173                         }
2174                 }
2175                 else {
2176                         for (i=0; i<(*tot); i++) {
2177                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2178                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2179                         }
2180                 }
2181         }
2182
2183 #ifdef PROJ_DEBUG_PRINT_CLIP
2184         /* include this at the bottom of the above function to debug the output */
2185
2186         {
2187                 /* If there are ever any problems, */
2188                 float test_uv[4][2];
2189                 int i;
2190                 if (is_ortho)   rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2191                 else                            rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2192                 printf("(  [(%f,%f), (%f,%f), (%f,%f), (%f,%f)], ", test_uv[0][0], test_uv[0][1],   test_uv[1][0], test_uv[1][1],    test_uv[2][0], test_uv[2][1],    test_uv[3][0], test_uv[3][1]);
2193                 
2194                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2195                 
2196                 printf("[");
2197                 for (i=0; i < (*tot); i++) {
2198                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2199                 }
2200                 printf("]),\\\n");
2201         }
2202 #endif
2203 }
2204
2205 /*
2206  * # This script creates faces in a blender scene from printed data above.
2207  *
2208  * project_ls = [
2209  * ...(output from above block)...
2210  * ]
2211  *
2212  * from Blender import Scene, Mesh, Window, sys, Mathutils
2213  *
2214  * import bpy
2215  *
2216  * V = Mathutils.Vector
2217  *
2218  * def main():
2219  *     sce = bpy.data.scenes.active
2220  *     
2221  *     for item in project_ls:
2222  *         bb = item[0]
2223  *         uv = item[1]
2224  *         poly = item[2]
2225  *         
2226  *         me = bpy.data.meshes.new()
2227  *         ob = sce.objects.new(me)
2228  *         
2229  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2230  *         me.faces.extend([(0,1,2,3),])
2231  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2232  *         me.faces.extend([(4,5,6),])
2233  *         
2234  *         vs = [V(p).xyz for p in poly]
2235  *         print len(vs)
2236  *         l = len(me.verts)
2237  *         me.verts.extend(vs)
2238  *         
2239  *         i = l
2240  *         while i < len(me.verts):
2241  *             ii = i+1
2242  *             if ii==len(me.verts):
2243  *                 ii = l
2244  *             me.edges.extend([i, ii])
2245  *             i+=1
2246  * 
2247  * if __name__ == '__main__':
2248  *     main()
2249  */
2250
2251
2252 #undef ISECT_1
2253 #undef ISECT_2
2254 #undef ISECT_3
2255 #undef ISECT_4
2256 #undef ISECT_ALL3
2257 #undef ISECT_ALL4
2258
2259         
2260 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2261  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2262 static int IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2263 {
2264         int i;
2265         if (line_point_side_v2(uv[tot-1], uv[0], pt) < 0.0f)
2266                 return 0;
2267         
2268         for (i=1; i<tot; i++) {
2269                 if (line_point_side_v2(uv[i-1], uv[i], pt) < 0.0f)
2270                         return 0;
2271                 
2272         }
2273         
2274         return 1;
2275 }
2276 static int IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2277 {
2278         int i;
2279         int side = (line_point_side_v2(uv[tot-1], uv[0], pt) > 0.0f);
2280         
2281         for (i=1; i<tot; i++) {
2282                 if ((line_point_side_v2(uv[i-1], uv[i], pt) > 0.0f) != side)
2283                         return 0;
2284                 
2285         }
2286         
2287         return 1;
2288 }
2289
2290 /* One of the most important function for projectiopn painting, since it selects the pixels to be added into each bucket.
2291  * initialize pixels from this face where it intersects with the bucket_index, optionally initialize pixels for removing seams */
2292 static void project_paint_face_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, const int face_index, const int image_index, rctf *bucket_bounds, const ImBuf *ibuf, const short clamp_u, const short clamp_v)
2293 {
2294         /* Projection vars, to get the 3D locations into screen space  */
2295         MemArena *arena = ps->arena_mt[thread_index];
2296         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2297         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2298         
2299         const MFace *mf = ps->dm_mface + face_index;
2300         const MTFace *tf = ps->dm_mtface + face_index;
2301         
2302         /* UV/pixel seeking data */
2303         int x; /* Image X-Pixel */
2304         int y;/* Image Y-Pixel */
2305         float mask;
2306         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2307         
2308         int side;
2309         float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to mf->v1,2,3 or mf->v1,3,4 */
2310         
2311         float *vCo[4]; /* vertex screenspace coords */
2312         
2313         float w[3], wco[3];
2314         
2315         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to tf->uv[0],1,2 or tf->uv[0],2,3 */
2316         float pixelScreenCo[4];
2317         
2318         rcti bounds_px; /* ispace bounds */
2319         /* vars for getting uvspace bounds */
2320         
2321         float tf_uv_pxoffset[4][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2322         float xhalfpx, yhalfpx;
2323         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2324         
2325         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2326         
2327         int i1, i2, i3;
2328         
2329         float uv_clip[8][2];
2330         int uv_clip_tot;
2331         const short is_ortho = ps->is_ortho;
2332         const short do_backfacecull = ps->do_backfacecull;
2333         const short do_clip= ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2334         
2335         vCo[0] = ps->dm_mvert[mf->v1].co;
2336         vCo[1] = ps->dm_mvert[mf->v2].co;
2337         vCo[2] = ps->dm_mvert[mf->v3].co;
2338         
2339         
2340         /* Use tf_uv_pxoffset instead of tf->uv so we can offset the UV half a pixel
2341          * this is done so we can avoid offseting all the pixels by 0.5 which causes
2342          * problems when wrapping negative coords */
2343         xhalfpx = (0.5f+   (PROJ_GEOM_TOLERANCE/3.0f)   ) / ibuf_xf;
2344         yhalfpx = (0.5f+   (PROJ_GEOM_TOLERANCE/4.0f)   ) / ibuf_yf;
2345         
2346         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2347          * Needed to add this offset since UV coords are often quads aligned to pixels.
2348          * In this case pixels can be exactly between 2 triangles causing nasty
2349          * artifacts.
2350          * 
2351          * This workaround can be removed and painting will still work on most cases
2352          * but since the first thing most people try is painting onto a quad- better make it work.
2353          */
2354
2355
2356
2357         tf_uv_pxoffset[0][0] = tf->uv[0][0] - xhalfpx;
2358         tf_uv_pxoffset[0][1] = tf->uv[0][1] - yhalfpx;
2359
2360         tf_uv_pxoffset[1][0] = tf->uv[1][0] - xhalfpx;
2361         tf_uv_pxoffset[1][1] = tf->uv[1][1] - yhalfpx;
2362         
2363         tf_uv_pxoffset[2][0] = tf->uv[2][0] - xhalfpx;
2364         tf_uv_pxoffset[2][1] = tf->uv[2][1] - yhalfpx;  
2365         
2366         if (mf->v4) {
2367                 vCo[3] = ps->dm_mvert[ mf->v4 ].co;
2368                 
2369                 tf_uv_pxoffset[3][0] = tf->uv[3][0] - xhalfpx;
2370                 tf_uv_pxoffset[3][1] = tf->uv[3][1] - yhalfpx;
2371                 side = 1;
2372         }
2373         else {
2374                 side = 0;
2375         }
2376         
2377         do {
2378                 if (side==1) {
2379                         i1=0; i2=2; i3=3;
2380                 }
2381                 else {
2382                         i1=0; i2=1; i3=2;
2383                 }
2384                 
2385                 uv1co = tf_uv_pxoffset[i1]; // was tf->uv[i1];
2386                 uv2co = tf_uv_pxoffset[i2]; // was tf->uv[i2];
2387                 uv3co = tf_uv_pxoffset[i3]; // was tf->uv[i3];
2388
2389                 v1coSS = ps->screenCoords[ (*(&mf->v1 + i1)) ];
2390                 v2coSS = ps->screenCoords[ (*(&mf->v1 + i2)) ];
2391                 v3coSS = ps->screenCoords[ (*(&mf->v1 + i3)) ];
2392                 
2393                 /* This funtion gives is a concave polyline in UV space from the clipped quad and tri*/
2394                 project_bucket_clip_face(
2395                                 is_ortho, bucket_bounds,
2396                                 v1coSS, v2coSS, v3coSS,
2397                                 uv1co, uv2co, uv3co,
2398                                 uv_clip, &uv_clip_tot
2399                 );
2400
2401                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2402 #if 0
2403                 if (uv_clip_tot>6) {
2404                         printf("this should never happen! %d\n", uv_clip_tot);
2405                 }
2406 #endif
2407
2408                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2409
2410                         if (clamp_u) {
2411                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2412                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2413                         }
2414
2415                         if (clamp_v) {
2416                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2417                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2418                         }
2419
2420                         /* clip face and */
2421                         
2422                         has_isect = 0;
2423                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2424                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2425                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2426
2427                                 has_x_isect = 0;
2428                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2429                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2430                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2431                                         
2432                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2433                                          * could check the poly direction but better to do this */
2434                                         if (    (do_backfacecull                && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2435                                                 (do_backfacecull==0             && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot))) {
2436                                                 
2437                                                 has_x_isect = has_isect = 1;
2438                                                 
2439                                                 if (is_ortho)   screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2440                                                 else                    screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2441                                                 
2442                                                 /* a pity we need to get the worldspace pixel location here */
2443                                                 if (do_clip) {
2444                                                         interp_v3_v3v3v3(wco, ps->dm_mvert[ (*(&mf->v1 + i1)) ].co, ps->dm_mvert[ (*(&mf->v1 + i2)) ].co, ps->dm_mvert[ (*(&mf->v1 + i3)) ].co, w);
2445                                                         if (ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2446                                                                 continue; /* Watch out that no code below this needs to run */
2447                                                         }
2448                                                 }
2449                                                 
2450                                                 /* Is this UV visible from the view? - raytrace */
2451                                                 /* project_paint_PickFace is less complex, use for testing */
2452                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == face_index) {
2453                                                 if (ps->do_occlude==0 || !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo)) {
2454                                                         
2455                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2456                                                         
2457                                                         if (mask > 0.0f) {
2458                                                                 BLI_linklist_prepend_arena(
2459                                                                         bucketPixelNodes,
2460                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index, image_index, pixelScreenCo, side, w),
2461                                                                         arena
2462                                                                 );
2463                                                         }
2464                                                 }
2465                                                 
2466                                         }
2467 //#if 0
2468                                         else if (has_x_isect) {
2469                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2470                                                 break;
2471                                         }
2472 //#endif
2473                                 }
2474                                 
2475                                 
2476 #if 0                   /* TODO - investigate why this dosnt work sometimes! it should! */
2477                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2478                                 if (has_x_isect==0 && has_isect) { 
2479                                         break;
2480                                 }
2481 #endif
2482                         }
2483                 }
2484         } while (side--);
2485
2486         
2487         
2488 #ifndef PROJ_DEBUG_NOSEAMBLEED
2489         if (ps->seam_bleed_px > 0.0f) {
2490                 int face_seam_flag;
2491                 
2492                 if (ps->thread_tot > 1)
2493                         BLI_lock_thread(LOCK_CUSTOM1); /* Other threads could be modifying these vars */
2494                 
2495                 face_seam_flag = ps->faceSeamFlags[face_index];
2496                 
2497                 /* are any of our edges un-initialized? */
2498                 if ((face_seam_flag & (PROJ_FACE_SEAM1|PROJ_FACE_NOSEAM1))==0 || 
2499                         (face_seam_flag & (PROJ_FACE_SEAM2|PROJ_FACE_NOSEAM2))==0 || 
2500                         (face_seam_flag & (PROJ_FACE_SEAM3|PROJ_FACE_NOSEAM3))==0 || 
2501                         (face_seam_flag & (PROJ_FACE_SEAM4|PROJ_FACE_NOSEAM4))==0
2502                 ) {
2503                         project_face_seams_init(ps, face_index, mf->v4);
2504                         face_seam_flag = ps->faceSeamFlags[face_index];
2505                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3, flag&PROJ_FACE_SEAM4);
2506                 }
2507                 
2508                 if ((face_seam_flag & (PROJ_FACE_SEAM1|PROJ_FACE_SEAM2|PROJ_FACE_SEAM3|PROJ_FACE_SEAM4))==0) {
2509                         
2510                         if (ps->thread_tot > 1)
2511                                 BLI_unlock_thread(LOCK_CUSTOM1); /* Other threads could be modifying these vars */
2512                         
2513                 }
2514                 else {
2515                         /* we have a seam - deal with it! */
2516                         
2517                         /* Now create new UV's for the seam face */
2518                         float (*outset_uv)[2] = ps->faceSeamUVs[face_index];
2519                         float insetCos[4][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2520
2521                         float fac;
2522                         float *vCoSS[4]; /* vertex screenspace coords */
2523                         
2524                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2525                         float edge_verts_inset_clip[2][3];
2526                         int fidx1, fidx2; /* face edge pairs - loop throuh these ((0,1), (1,2), (2,3), (3,0)) or ((0,1), (1,2), (2,0)) for a tri */
2527                         
2528                         float seam_subsection[4][2];
2529                         float fac1, fac2, ftot;
2530                         
2531                         
2532                         if (outset_uv[0][0]==FLT_MAX) /* first time initialize */
2533                                 uv_image_outset(tf_uv_pxoffset, outset_uv, ps->seam_bleed_px, ibuf->x, ibuf->y, mf->v4);
2534                         
2535                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2536                         if (ps->thread_tot > 1)
2537                                 BLI_unlock_thread(LOCK_CUSTOM1); /* Other threads could be modifying these vars */
2538                         
2539                         vCoSS[0] = ps->screenCoords[mf->v1];
2540                         vCoSS[1] = ps->screenCoords[mf->v2];
2541                         vCoSS[2] = ps->screenCoords[mf->v3];
2542                         if (mf->v4)
2543                                 vCoSS[3] = ps->screenCoords[ mf->v4 ];
2544                         
2545                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2546                         if (is_ortho) {
2547                                 if (mf->v4)     scale_quad(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2548                                 else            scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2549                         }
2550                         else {
2551                                 if (mf->v4)     scale_quad(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2552                                 else            scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2553                         }
2554                         
2555                         side = 0; /* for triangles this wont need to change */
2556                         
2557                         for (fidx1 = 0; fidx1 < (mf->v4 ? 4 : 3); fidx1++) {
2558                                 if (mf->v4)             fidx2 = (fidx1==3) ? 0 : fidx1+1; /* next fidx in the face (0,1,2,3) -> (1,2,3,0) */
2559                                 else                    fidx2 = (fidx1==2) ? 0 : fidx1+1; /* next fidx in the face (0,1,2) -> (1,2,0) */
2560                                 
2561                                 if (    (face_seam_flag & (1<<fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2562                                                 line_clip_rect2f(bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1])
2563                                 ) {
2564
2565                                         ftot = len_v2v2(vCoSS[fidx1], vCoSS[fidx2]); /* screenspace edge length */
2566                                         
2567                                         if (ftot > 0.0f) { /* avoid div by zero */
2568                                                 if (mf->v4) {
2569                                                         if (fidx1==2 || fidx2==2)       side= 1;
2570                                                         else                                            side= 0;
2571                                                 }
2572                                                 
2573                                                 fac1 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[0]) / ftot;
2574                                                 fac2 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[1]) / ftot;
2575                                                 
2576                                                 interp_v2_v2v2(seam_subsection[0], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac1);
2577                                                 interp_v2_v2v2(seam_subsection[1], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac2);
2578
2579                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2580                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2581                                                 
2582                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2583                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2584                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2585                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2586                                                 
2587
2588                                                 if (pixel_bounds_uv(seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3], &bounds_px, ibuf->x, ibuf->y, 1)) {
2589                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2590                                                         
2591                                                         has_isect = 0;
2592                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2593                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2594                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2595                                                                 
2596                                                                 has_x_isect = 0;
2597                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2598                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2599                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2600                                                                         
2601                                                                         /* test we're inside uvspace bucket and triangle bounds */
2602                                                                         if (isect_point_quad_v2(uv, seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3])) {
2603                                                                                 
2604                                                                                 /* We need to find the closest point along the face edge,
2605                                                                                  * getting the screen_px_from_*** wont work because our actual location
2606                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2607                                                                                  * our location on the side of the face's UV */
2608 #if 0
2609                                                                                 if (is_ortho)   screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2610                                                                                 else                                    screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2611 #endif
2612                                                                                 
2613                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2614                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2615                                                                                 
2616                                                                                 fac = line_point_factor_v2(uv, seam_subsection[0], seam_subsection[1]);
2617                                                                                 if (fac < 0.0f)         { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[0]); }
2618                                                                                 else if (fac > 1.0f)    { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[1]); }
2619                                                                                 else                            { interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac); }
2620                                                                                 
2621                                                                                 if (!is_ortho) {
2622                                                                                         pixelScreenCo[3] = 1.0f;
2623                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2624                                                                                         pixelScreenCo[0] = (float)(ps->winx/2.0f)+(ps->winx/2.0f)*pixelScreenCo[0]/pixelScreenCo[3];
2625                                                                                         pixelScreenCo[1] = (float)(ps->winy/2.0f)+(ps->winy/2.0f)*pixelScreenCo[1]/pixelScreenCo[3];
2626                                                                                         pixelScreenCo[2] = pixelScreenCo[2]/pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2627                                                                                 }
2628                                                                                 
2629                                                                                 if (ps->do_occlude==0 || !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo)) {
2630                                                                                         
2631                                                                                         /* Only bother calculating the weights if we intersect */
2632                                                                                         if (ps->do_mask_normal || ps->dm_mtface_clone) {
2633 #if 1
2634                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2635                                                                                                 float uv_close[2];
2636                                                                                                 float fac= closest_to_line_v2(uv_close, uv, tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2]);
2637                                                                                                 if              (fac < 0.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx1]);
2638                                                                                                 else if (fac > 1.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx2]);
2639
2640                                                                                                 if (side) {
2641                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[2], tf_uv_pxoffset[3], uv_close, w);
2642                                                                                                 }
2643                                                                                                 else {
2644                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[1], tf_uv_pxoffset[2], uv_close, w);
2645                                                                                                 }
2646 #else                                                                                   /* this is buggy with quads, don't use for now */
2647
2648                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2649                                                                                                 fac = fac1 + (fac * (fac2-fac1));
2650
2651                                                                                                 w[0]=w[1]=w[2]= 0.0;
2652                                                                                                 if (side) {
2653                                                                                                         w[fidx1?fidx1-1:0] = 1.0f-fac;
2654                                                                                                         w[fidx2?fidx2-1:0] = fac;
2655                                                                                                 }
2656                                                                                                 else {
2657                                                                                                         w[fidx1] = 1.0f-fac;
2658                                                                                                         w[fidx2] = fac;
2659                                                                                                 }
2660 #endif
2661                                                                                         }
2662                                                                                         
2663                                                                                         /* a pity we need to get the worldspace pixel location here */
2664                                                                                         if (do_clip) {
2665                                                                                                 if (side)       interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v3].co, ps->dm_mvert[mf->v4].co, w);
2666                                                                                                 else            interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
2667
2668                                                                                                 if (ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2669                                                                                                         continue; /* Watch out that no code below this needs to run */
2670                                                                                                 }
2671                                                                                         }
2672                                                                                         
2673                                                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2674                                                                                         
2675                                                                                         if (mask > 0.0f) {
2676                                                                                                 BLI_linklist_prepend_arena(
2677                                                                                                         bucketPixelNodes,
2678                                                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index, image_index, pixelScreenCo, side, w),
2679                                                                                                         arena
2680                                                                                                 );
2681                                                                                         }
2682                                                                                         
2683                                                                                 }
2684                                                                         }
2685                                                                         else if (has_x_isect) {
2686                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2687                                                                                 break;
2688                                                                         }
2689                                                                 }
2690                                                                 
2691 #if 0                                                   /* TODO - investigate why this dosnt work sometimes! it should! */
2692                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2693                                                                 if (has_x_isect==0 && has_isect) { 
2694                                                                         break;
2695                                                                 }
2696 #endif
2697                                                         }
2698                                                 }
2699                                         }
2700                                 }
2701                         }
2702                 }
2703         }
2704 #endif // PROJ_DEBUG_NOSEAMBLEED
2705 }
2706
2707
2708 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2709 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2710 {
2711         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2712         /* XXX: the offset of 0.5 is always truncated to zero and the offset of 1.5f is always truncated to 1, is this really correct?? - jwilkins */
2713         bucketMin[0] = (int)((int)(((float)(min[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 0.5f); /* these offsets of 0.5 and 1.5 seem odd but they are correct */
2714         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2715         
2716         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2717         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2718         
2719         /* in case the rect is outside the mesh 2d bounds */
2720         CLAMP(bucketMin[0], 0, ps->buckets_x);
2721         CLAMP(bucketMin[1], 0, ps->buckets_y);
2722         
2723         CLAMP(bucketMax[0], 0, ps->buckets_x);
2724         CLAMP(bucketMax[1], 0, ps->buckets_y);
2725 }
2726
2727 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2728 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2729 {
2730         bucket_bounds->xmin =   ps->screenMin[0]+((bucket_x)*(ps->screen_width / ps->buckets_x));               /* left */
2731         bucket_bounds->xmax =   ps->screenMin[0]+((bucket_x+1)*(ps->screen_width / ps->buckets_x));     /* right */
2732         
2733         bucket_bounds->ymin =   ps->screenMin[1]+((bucket_y)*(ps->screen_height / ps->buckets_y));              /* bottom */
2734         bucket_bounds->ymax =   ps->screenMin[1]+((bucket_y+1)*(ps->screen_height  / ps->buckets_y));   /* top */
2735 }
2736
2737 /* Fill this bucket with pixels from the faces that intersect it.
2738  * 
2739  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2740 static void project_bucket_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, rctf *bucket_bounds)
2741 {
2742         LinkNode *node;
2743         int face_index, image_index=0;
2744         ImBuf *ibuf = NULL;
2745         Image *tpage_last = NULL, *tpage;
2746         Image *ima = NULL;
2747
2748         if (ps->image_tot==1) {
2749                 /* Simple loop, no context switching */
2750                 ibuf = ps->projImages[0].ibuf;
2751                 ima = ps->projImages[0].ima;
2752
2753                 for (node = ps->bucketFaces[bucket_index]; node; node= node->next) { 
2754                         project_paint_face_init(ps, thread_index, bucket_index, GET_INT_FROM_POINTER(node->link), 0, bucket_bounds, ibuf, ima->tpageflag & IMA_CLAMP_U, ima->tpageflag & IMA_CLAMP_V);
2755                 }
2756         }
2757         else {
2758                 
2759                 /* More complicated loop, switch between images */
2760                 for (node = ps->bucketFaces[bucket_index]; node; node= node->next) {
2761                         face_index = GET_INT_FROM_POINTER(node->link);
2762                                 
2763                         /* Image context switching */
2764                         tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
2765                         if (tpage_last != tpage) {
2766                                 tpage_last = tpage;
2767
2768                                 for (image_index=0; image_index < ps->image_tot; image_index++) {
2769                                         if (ps->projImages[image_index].ima == tpage_last) {
2770                                                 ibuf = ps->projImages[image_index].ibuf;
2771                                                 ima = ps->projImages[image_index].ima;
2772                                                 break;
2773                                         }
2774                                 }
2775                         }
2776                         /* context switching done */
2777                         
2778                         project_paint_face_init(ps, thread_index, bucket_index, face_index, image_index, bucket_bounds, ibuf, ima->tpageflag & IMA_CLAMP_U, ima->tpageflag & IMA_CLAMP_V);
2779                 }
2780         }
2781         
2782         ps->bucketFlags[bucket_index] |= PROJ_BUCKET_INIT;
2783 }
2784
2785
2786 /* We want to know if a bucket and a face overlap in screen-space
2787  * 
2788  * Note, if this ever returns false positives its not that bad, since a face in the bounding area will have its pixels
2789  * calculated when it might not be needed later, (at the moment at least)
2790  * obviously it shouldn't have bugs though */
2791
2792 static int project_bucket_face_isect(ProjPaintState *ps, int bucket_x, int bucket_y, const MFace *mf)
2793 {
2794         /* TODO - replace this with a tricker method that uses sideofline for all screenCoords's edges against the closest bucket corner */
2795         rctf bucket_bounds;
2796         float p1[2], p2[2], p3[2], p4[2];
2797         float *v, *v1,*v2,*v3,*v4=NULL;
2798         int fidx;
2799         
2800         project_bucket_bounds(ps, bucket_x, bucket_y, &bucket_bounds);
2801         
2802         /* Is one of the faces verts in the bucket bounds? */
2803         
2804         fidx = mf->v4 ? 3:2;
2805         do {
2806                 v = ps->screenCoords[ (*(&mf->v1 + fidx)) ];
2807                 if (BLI_in_rctf(&bucket_bounds, v[0], v[1])) {
2808                         return 1;
2809                 }
2810         } while (fidx--);
2811         
2812         v1 = ps->screenCoords[mf->v1];
2813         v2 = ps->screenCoords[mf->v2];
2814         v3 = ps->screenCoords[mf->v3];
2815         if (mf->v4) {
2816                 v4 = ps->screenCoords[mf->v4];
2817         }
2818         
2819         p1[0] = bucket_bounds.xmin; p1[1] = bucket_bounds.ymin;
2820         p2[0] = bucket_bounds.xmin;     p2[1] = bucket_bounds.ymax;
2821         p3[0] = bucket_bounds.xmax;     p3[1] = bucket_bounds.ymax;
2822         p4[0] = bucket_bounds.xmax;     p4[1] = bucket_bounds.ymin;
2823                 
2824         if (mf->v4) {
2825                 if ( isect_point_quad_v2(p1, v1, v2, v3, v4) ||
2826                      isect_point_quad_v2(p2, v1, v2, v3, v4) ||
2827                      isect_point_quad_v2(p3, v1, v2, v3, v4) ||
2828                      isect_point_quad_v2(p4, v1, v2, v3, v4) ||
2829
2830                         /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2831                         (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3) || isect_line_line_v2(p1, p2, v3, v4)) ||
2832                         (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3) || isect_line_line_v2(p2, p3, v3, v4)) ||
2833                         (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3) || isect_line_line_v2(p3, p4, v3, v4)) ||
2834                         (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3) || isect_line_line_v2(p4, p1, v3, v4))
2835                 ) {
2836                         return 1;
2837                 }
2838         }
2839         else {
2840                 if ( isect_point_tri_v2(p1, v1, v2, v3) ||
2841                      isect_point_tri_v2(p2, v1, v2, v3) ||
2842                      isect_point_tri_v2(p3, v1, v2, v3) ||
2843                      isect_point_tri_v2(p4, v1, v2, v3) ||
2844                         /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2845                         (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3)) ||