code cleanup: (dont include ';' in defines), last commit also missed changes to paint...
[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         /* viewport texture paint only, but _not_ project paint */
164         Object *ob;
165         int faceindex;
166         float uv[2];
167         int do_facesel;
168
169         DerivedMesh    *dm;
170         int                     dm_totface;
171         int                             dm_release;
172
173         MFace              *dm_mface;
174         MTFace             *dm_mtface;
175 } ImagePaintState;
176
177 typedef struct ImagePaintPartialRedraw {
178         int x1, y1, x2, y2;
179         int enabled;
180 } ImagePaintPartialRedraw;
181
182 typedef struct ImagePaintRegion {
183         int destx, desty;
184         int srcx, srcy;
185         int width, height;
186 } ImagePaintRegion;
187
188 /* ProjectionPaint defines */
189
190 /* approx the number of buckets to have under the brush,
191  * used with the brush size to set the ps->buckets_x and ps->buckets_y value.
192  * 
193  * When 3 - a brush should have ~9 buckets under it at once
194  * ...this helps for threading while painting as well as
195  * avoiding initializing pixels that wont touch the brush */
196 #define PROJ_BUCKET_BRUSH_DIV 4
197
198 #define PROJ_BUCKET_RECT_MIN 4
199 #define PROJ_BUCKET_RECT_MAX 256
200
201 #define PROJ_BOUNDBOX_DIV 8
202 #define PROJ_BOUNDBOX_SQUARED  (PROJ_BOUNDBOX_DIV * PROJ_BOUNDBOX_DIV)
203
204 //#define PROJ_DEBUG_PAINT 1
205 //#define PROJ_DEBUG_NOSEAMBLEED 1
206 //#define PROJ_DEBUG_PRINT_CLIP 1
207 #define PROJ_DEBUG_WINCLIP 1
208
209 /* projectFaceSeamFlags options */
210 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
211 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
212 #define PROJ_FACE_SEAM1 (1<<0)  /* If this face has a seam on any of its edges */
213 #define PROJ_FACE_SEAM2 (1<<1)
214 #define PROJ_FACE_SEAM3 (1<<2)
215 #define PROJ_FACE_SEAM4 (1<<3)
216
217 #define PROJ_FACE_NOSEAM1       (1<<4)
218 #define PROJ_FACE_NOSEAM2       (1<<5)
219 #define PROJ_FACE_NOSEAM3       (1<<6)
220 #define PROJ_FACE_NOSEAM4       (1<<7)
221
222 #define PROJ_SRC_VIEW           1
223 #define PROJ_SRC_IMAGE_CAM      2
224 #define PROJ_SRC_IMAGE_VIEW     3
225
226 #define PROJ_VIEW_DATA_ID "view_data"
227 #define PROJ_VIEW_DATA_SIZE (4*4 + 4*4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
228
229
230 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
231  * as this number approaches  1.0f the likelihood increases of float precision errors where
232  * it is occluded by an adjacent face */
233 #define PROJ_FACE_SCALE_SEAM    0.99f
234
235 #define PROJ_BUCKET_NULL                0
236 #define PROJ_BUCKET_INIT                (1<<0)
237 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
238
239 /* used for testing doubles, if a point is on a line etc */
240 #define PROJ_GEOM_TOLERANCE 0.00075f
241
242 /* vert flags */
243 #define PROJ_VERT_CULL 1
244
245 #define PI_80_DEG ((M_PI_2 / 9) * 8)
246
247 /* This is mainly a convenience struct used so we can keep an array of images we use
248  * Thir imbufs, etc, in 1 array, When using threads this array is copied for each thread
249  * because 'partRedrawRect' and 'touch' values would not be thread safe */
250 typedef struct ProjPaintImage {
251         Image *ima;
252         ImBuf *ibuf;
253         ImagePaintPartialRedraw *partRedrawRect;
254         void **undoRect; /* only used to build undo tiles after painting */
255         int touch;
256 } ProjPaintImage;
257
258 /* Main projection painting struct passed to all projection painting functions */
259 typedef struct ProjPaintState {
260         View3D *v3d;
261         RegionView3D *rv3d;
262         ARegion *ar;
263         Scene *scene;
264         int source; /* PROJ_SRC_**** */
265
266         Brush *brush;
267         short tool, blend;
268         Object *ob;
269         /* end similarities with ImagePaintState */
270         
271         DerivedMesh    *dm;
272         int                     dm_totface;
273         int                     dm_totvert;
274         int                             dm_release;
275         
276         MVert              *dm_mvert;
277         MFace              *dm_mface;
278         MTFace             *dm_mtface;
279         MTFace             *dm_mtface_clone;    /* other UV map, use for cloning between layers */
280         MTFace             *dm_mtface_stencil;
281         
282         /* projection painting only */
283         MemArena *arena_mt[BLENDER_MAX_THREADS];/* for multithreading, the first item is sometimes used for non threaded cases too */
284         LinkNode **bucketRect;                          /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
285         LinkNode **bucketFaces;                         /* bucketRect aligned array linkList of faces overlapping each bucket */
286         unsigned char *bucketFlags;                                     /* store if the bucks have been initialized  */
287 #ifndef PROJ_DEBUG_NOSEAMBLEED
288         char *faceSeamFlags;                            /* store info about faces, if they are initialized etc*/
289         float (*faceSeamUVs)[4][2];                     /* expanded UVs for faces to use as seams */
290         LinkNode **vertFaces;                           /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
291 #endif
292         char *vertFlags;                                        /* store options per vert, now only store if the vert is pointing away from the view */
293         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 */
294         int buckets_y;
295         
296         ProjPaintImage *projImages;
297         
298         int image_tot;                          /* size of projectImages array */
299         
300         float (*screenCoords)[4];       /* verts projected into floating point screen space */
301         
302         float screenMin[2];                     /* 2D bounds for mesh verts on the screen's plane (screenspace) */
303         float screenMax[2]; 
304         float screen_width;                     /* Calculated from screenMin & screenMax */
305         float screen_height;
306         int winx, winy;                         /* from the carea or from the projection render */
307         
308         /* options for projection painting */
309         int do_layer_clone;
310         int do_layer_stencil;
311         int do_layer_stencil_inv;
312         
313         short do_occlude;                       /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
314         short do_backfacecull;  /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
315         short do_mask_normal;                   /* mask out pixels based on their normals */
316         short do_new_shading_nodes;     /* cache scene_use_new_shading_nodes value */
317         float normal_angle;                             /* what angle to mask at*/
318         float normal_angle_inner;
319         float normal_angle_range;               /* difference between normal_angle and normal_angle_inner, for easy access */
320         
321         short is_ortho;
322         short is_airbrush;                                      /* only to avoid using (ps.brush->flag & BRUSH_AIRBRUSH) */
323         short is_texbrush;                                      /* only to avoid running  */
324 #ifndef PROJ_DEBUG_NOSEAMBLEED
325         float seam_bleed_px;
326 #endif
327         /* clone vars */
328         float cloneOffset[2];
329         
330         float projectMat[4][4];         /* Projection matrix, use for getting screen coords */
331         float viewDir[3];                       /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
332         float viewPos[3];                       /* View location in object relative 3D space, so can compare to verts  */
333         float clipsta, clipend;
334         
335         /* reproject vars */
336         Image *reproject_image;
337         ImBuf *reproject_ibuf;
338
339
340         /* threads */
341         int thread_tot;
342         int bucketMin[2];
343         int bucketMax[2];
344         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
345 } ProjPaintState;
346
347 typedef union pixelPointer
348 {
349         float *f_pt;                    /* float buffer */
350         unsigned int *uint_pt; /* 2 ways to access a char buffer */
351         unsigned char *ch_pt;
352 } PixelPointer;
353
354 typedef union pixelStore
355 {
356         unsigned char ch[4];
357         unsigned int uint;
358         float f[4];
359 } PixelStore;
360
361 typedef struct ProjPixel {
362         float projCoSS[2]; /* the floating point screen projection of this pixel */
363         
364         /* Only used when the airbrush is disabled.
365          * Store the max mask value to avoid painting over an area with a lower opacity
366          * with an advantage that we can avoid touching the pixel at all, if the 
367          * new mask value is lower then mask_max */
368         unsigned short mask_max;
369         
370         /* for various reasons we may want to mask out painting onto this pixel */
371         unsigned short mask;
372         
373         short x_px, y_px;
374         
375         PixelStore origColor;
376         PixelStore newColor;
377         PixelPointer pixel;
378         
379         short image_index; /* if anyone wants to paint onto more then 32768 images they can bite me */
380         unsigned char bb_cell_index;
381 } ProjPixel;
382
383 typedef struct ProjPixelClone {
384         struct ProjPixel __pp;
385         PixelStore clonepx;
386 } ProjPixelClone;
387
388 /* Finish projection painting structs */
389
390 typedef struct UndoImageTile {
391         struct UndoImageTile *next, *prev;
392
393         char idname[MAX_ID_NAME];       /* name instead of pointer*/
394         char ibufname[IB_FILENAME_SIZE];
395
396         void *rect;
397         int x, y;
398
399         short source, use_float;
400         char gen_type;
401 } UndoImageTile;
402
403 static ImagePaintPartialRedraw imapaintpartial = {0, 0, 0, 0, 0};
404
405 /* UNDO */
406
407 static void undo_copy_tile(UndoImageTile *tile, ImBuf *tmpibuf, ImBuf *ibuf, int restore)
408 {
409         /* copy or swap contents of tile->rect and region in ibuf->rect */
410         IMB_rectcpy(tmpibuf, ibuf, 0, 0, tile->x*IMAPAINT_TILE_SIZE,
411                 tile->y*IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE);
412
413         if (ibuf->rect_float) {
414                 SWAP(void*, tmpibuf->rect_float, tile->rect);
415         }
416         else {
417                 SWAP(void*, tmpibuf->rect, tile->rect);
418         }
419         
420         if (restore)
421                 IMB_rectcpy(ibuf, tmpibuf, tile->x*IMAPAINT_TILE_SIZE,
422                         tile->y*IMAPAINT_TILE_SIZE, 0, 0, IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE);
423 }
424
425 static void *image_undo_push_tile(Image *ima, ImBuf *ibuf, ImBuf **tmpibuf, int x_tile, int y_tile)
426 {
427         ListBase *lb= undo_paint_push_get_list(UNDO_PAINT_IMAGE);
428         UndoImageTile *tile;
429         int allocsize;
430         short use_float = ibuf->rect_float ? 1 : 0;
431
432         for (tile=lb->first; tile; tile=tile->next)
433                 if (tile->x == x_tile && tile->y == y_tile && ima->gen_type == tile->gen_type && ima->source == tile->source)
434                         if (tile->use_float == use_float)
435                                 if (strcmp(tile->idname, ima->id.name)==0 && strcmp(tile->ibufname, ibuf->name)==0)
436                                         return tile->rect;
437         
438         if (*tmpibuf==NULL)
439                 *tmpibuf = IMB_allocImBuf(IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, 32, IB_rectfloat|IB_rect);
440         
441         tile= MEM_callocN(sizeof(UndoImageTile), "UndoImageTile");
442         BLI_strncpy(tile->idname, ima->id.name, sizeof(tile->idname));
443         tile->x= x_tile;
444         tile->y= y_tile;
445
446         allocsize= IMAPAINT_TILE_SIZE*IMAPAINT_TILE_SIZE*4;
447         allocsize *= (ibuf->rect_float)? sizeof(float): sizeof(char);
448         tile->rect= MEM_mapallocN(allocsize, "UndeImageTile.rect");
449
450         BLI_strncpy(tile->ibufname, ibuf->name, sizeof(tile->ibufname));
451
452         tile->gen_type= ima->gen_type;
453         tile->source= ima->source;
454         tile->use_float= use_float;
455
456         undo_copy_tile(tile, *tmpibuf, ibuf, 0);
457         undo_paint_push_count_alloc(UNDO_PAINT_IMAGE, allocsize);
458
459         BLI_addtail(lb, tile);
460         
461         return tile->rect;
462 }
463
464 static void image_undo_restore(bContext *C, ListBase *lb)
465 {
466         Main *bmain= CTX_data_main(C);
467         Image *ima = NULL;
468         ImBuf *ibuf, *tmpibuf;
469         UndoImageTile *tile;
470
471         tmpibuf= IMB_allocImBuf(IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, 32,
472                                                         IB_rectfloat|IB_rect);
473         
474         for (tile=lb->first; tile; tile=tile->next) {
475                 short use_float;
476
477                 /* find image based on name, pointer becomes invalid with global undo */
478                 if (ima && strcmp(tile->idname, ima->id.name)==0) {
479                         /* ima is valid */
480                 }
481                 else {
482                         ima= BLI_findstring(&bmain->image, tile->idname, offsetof(ID, name));
483                 }
484
485                 ibuf= BKE_image_get_ibuf(ima, NULL);
486
487                 if (ima && ibuf && strcmp(tile->ibufname, ibuf->name)!=0) {
488                         /* current ImBuf filename was changed, probably current frame
489                          * was changed when paiting on image sequence, rather than storing
490                          * full image user (which isn't so obvious, btw) try to find ImBuf with
491                          * matched file name in list of already loaded images */
492
493                         ibuf= BLI_findstring(&ima->ibufs, tile->ibufname, offsetof(ImBuf, name));
494                 }
495
496                 if (!ima || !ibuf || !(ibuf->rect || ibuf->rect_float))
497                         continue;
498
499                 if (ima->gen_type != tile->gen_type || ima->source != tile->source)
500                         continue;
501
502                 use_float = ibuf->rect_float ? 1 : 0;
503
504                 if (use_float != tile->use_float)
505                         continue;
506
507                 undo_copy_tile(tile, tmpibuf, ibuf, 1);
508
509                 GPU_free_image(ima); /* force OpenGL reload */
510                 if (ibuf->rect_float)
511                         ibuf->userflags |= IB_RECT_INVALID; /* force recreate of char rect */
512                 if (ibuf->mipmap[0])
513                         ibuf->userflags |= IB_MIPMAP_INVALID; /* force mipmap recreatiom */
514
515         }
516
517         IMB_freeImBuf(tmpibuf);
518 }
519
520 static void image_undo_free(ListBase *lb)
521 {
522         UndoImageTile *tile;
523
524         for (tile=lb->first; tile; tile=tile->next)
525                 MEM_freeN(tile->rect);
526 }
527
528 /* get active image for face depending on old/new shading system */
529
530 static Image *imapaint_face_image(const ImagePaintState *s, int face_index)
531 {
532         Image *ima;
533
534         if (scene_use_new_shading_nodes(s->scene)) {
535                 MFace *mf = &s->dm_mface[face_index];
536                 ED_object_get_active_image(s->ob, mf->mat_nr, &ima, NULL, NULL);
537         }
538         else {
539                 MTFace *tf = &s->dm_mtface[face_index];
540                 ima = tf->tpage;
541         }
542
543         return ima;
544 }
545
546 static Image *project_paint_face_image(const ProjPaintState *ps, MTFace *dm_mtface, int face_index)
547 {
548         Image *ima;
549
550         if (ps->do_new_shading_nodes) { /* cached scene_use_new_shading_nodes result */
551                 MFace *mf = ps->dm_mface+face_index;
552                 ED_object_get_active_image(ps->ob, mf->mat_nr, &ima, NULL, NULL);
553         }
554         else {
555                 ima = dm_mtface[face_index].tpage;
556         }
557
558         return ima;
559 }
560
561 /* fast projection bucket array lookup, use the safe version for bound checking  */
562 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
563 {
564         /* If we were not dealing with screenspace 2D coords we could simple do...
565          * ps->bucketRect[x + (y*ps->buckets_y)] */
566         
567         /* please explain?
568          * projCoSS[0] - ps->screenMin[0]       : zero origin
569          * ... / ps->screen_width                               : range from 0.0 to 1.0
570          * ... * ps->buckets_x          : use as a bucket index
571          *
572          * Second multiplication does similar but for vertical offset
573          */
574         return  (       (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) + 
575                 (       (       (int)(((projCoSS[1] - ps->screenMin[1])  / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
576 }
577
578 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
579 {
580         int bucket_index = project_bucket_offset(ps, projCoSS);
581         
582         if (bucket_index < 0 || bucket_index >= ps->buckets_x*ps->buckets_y) {  
583                 return -1;
584         }
585         else {
586                 return bucket_index;
587         }
588 }
589
590 /* still use 2D X,Y space but this works for verts transformed by a perspective matrix, using their 4th component as a weight */
591 static void barycentric_weights_v2_persp(float v1[4], float v2[4], float v3[4], float co[2], float w[3])
592 {
593         float wtot_inv, wtot;
594
595         w[0] = area_tri_signed_v2(v2, v3, co) / v1[3];
596         w[1] = area_tri_signed_v2(v3, v1, co) / v2[3];
597         w[2] = area_tri_signed_v2(v1, v2, co) / v3[3];
598         wtot = w[0]+w[1]+w[2];
599
600         if (wtot != 0.0f) {
601                 wtot_inv = 1.0f/wtot;
602
603                 w[0] = w[0]*wtot_inv;
604                 w[1] = w[1]*wtot_inv;
605                 w[2] = w[2]*wtot_inv;
606         }
607         else /* dummy values for zero area face */
608                 w[0] = w[1] = w[2] = 1.0f/3.0f;
609 }
610
611 static float VecZDepthOrtho(float pt[2], float v1[3], float v2[3], float v3[3], float w[3])
612 {
613         barycentric_weights_v2(v1, v2, v3, pt, w);
614         return (v1[2]*w[0]) + (v2[2]*w[1]) + (v3[2]*w[2]);
615 }
616
617 static float VecZDepthPersp(float pt[2], float v1[4], float v2[4], float v3[4], float w[3])
618 {
619         float wtot_inv, wtot;
620         float w_tmp[3];
621
622         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
623         /* for the depth we need the weights to match what
624          * barycentric_weights_v2 would return, in this case its easiest just to
625          * undo the 4th axis division and make it unit-sum
626          *
627          * don't call barycentric_weights_v2() becaue our callers expect 'w'
628          * to be weighted from the perspective */
629         w_tmp[0]= w[0] * v1[3];
630         w_tmp[1]= w[1] * v2[3];
631         w_tmp[2]= w[2] * v3[3];
632
633         wtot = w_tmp[0]+w_tmp[1]+w_tmp[2];
634
635         if (wtot != 0.0f) {
636                 wtot_inv = 1.0f/wtot;
637
638                 w_tmp[0] = w_tmp[0]*wtot_inv;
639                 w_tmp[1] = w_tmp[1]*wtot_inv;
640                 w_tmp[2] = w_tmp[2]*wtot_inv;
641         }
642         else /* dummy values for zero area face */
643                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f/3.0f;
644         /* done mimicing barycentric_weights_v2() */
645
646         return (v1[2]*w_tmp[0]) + (v2[2]*w_tmp[1]) + (v3[2]*w_tmp[2]);
647 }
648
649
650 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
651 static int project_paint_PickFace(const ProjPaintState *ps, float pt[2], float w[3], int *side)
652 {
653         LinkNode *node;
654         float w_tmp[3];
655         float *v1, *v2, *v3, *v4;
656         int bucket_index;
657         int face_index;
658         int best_side = -1;
659         int best_face_index = -1;
660         float z_depth_best = FLT_MAX, z_depth;
661         MFace *mf;
662         
663         bucket_index = project_bucket_offset_safe(ps, pt);
664         if (bucket_index==-1)
665                 return -1;
666         
667         
668         
669         /* we could return 0 for 1 face buckets, as long as this function assumes
670          * that the point its testing is only every originated from an existing face */
671         
672         for (node= ps->bucketFaces[bucket_index]; node; node= node->next) {
673                 face_index = GET_INT_FROM_POINTER(node->link);
674                 mf= ps->dm_mface + face_index;
675                 
676                 v1= ps->screenCoords[mf->v1];
677                 v2= ps->screenCoords[mf->v2];
678                 v3= ps->screenCoords[mf->v3];
679                 
680                 if (isect_point_tri_v2(pt, v1, v2, v3)) {
681                         if (ps->is_ortho)       z_depth= VecZDepthOrtho(pt, v1, v2, v3, w_tmp);
682                         else                            z_depth= VecZDepthPersp(pt, v1, v2, v3, w_tmp);
683                         
684                         if (z_depth < z_depth_best) {
685                                 best_face_index = face_index;
686                                 best_side = 0;
687                                 z_depth_best = z_depth;
688                                 copy_v3_v3(w, w_tmp);
689                         }
690                 }
691                 else if (mf->v4) {
692                         v4= ps->screenCoords[mf->v4];
693                         
694                         if (isect_point_tri_v2(pt, v1, v3, v4)) {
695                                 if (ps->is_ortho)       z_depth= VecZDepthOrtho(pt, v1, v3, v4, w_tmp);
696                                 else                            z_depth= VecZDepthPersp(pt, v1, v3, v4, w_tmp);
697
698                                 if (z_depth < z_depth_best) {
699                                         best_face_index = face_index;
700                                         best_side= 1;
701                                         z_depth_best = z_depth;
702                                         copy_v3_v3(w, w_tmp);
703                                 }
704                         }
705                 }
706         }
707         
708         *side = best_side;
709         return best_face_index; /* will be -1 or a valid face */
710 }
711
712 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
713 static void uvco_to_wrapped_pxco(float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
714 {
715         /* use */
716         *x = (float)fmodf(uv[0], 1.0f);
717         *y = (float)fmodf(uv[1], 1.0f);
718         
719         if (*x < 0.0f) *x += 1.0f;
720         if (*y < 0.0f) *y += 1.0f;
721         
722         *x = *x * ibuf_x - 0.5f;
723         *y = *y * ibuf_y - 0.5f;
724 }
725
726 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
727 static int project_paint_PickColor(const ProjPaintState *ps, float pt[2], float *rgba_fp, unsigned char *rgba, const int interp)
728 {
729         float w[3], uv[2];
730         int side;
731         int face_index;
732         MTFace *tf;
733         Image *ima;
734         ImBuf *ibuf;
735         int xi, yi;
736         
737         
738         face_index = project_paint_PickFace(ps, pt, w, &side);
739         
740         if (face_index == -1)
741                 return 0;
742         
743         tf = ps->dm_mtface + face_index;
744         
745         if (side == 0) {
746                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[1], tf->uv[2], w);
747         }
748         else { /* QUAD */
749                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[2], tf->uv[3], w);
750         }
751
752         ima = project_paint_face_image(ps, ps->dm_mtface, face_index);
753         ibuf = ima->ibufs.first; /* we must have got the imbuf before getting here */
754         if (!ibuf) return 0;
755         
756         if (interp) {
757                 float x, y;
758                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
759                 
760                 if (ibuf->rect_float) {
761                         if (rgba_fp) {
762                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
763                         }
764                         else {
765                                 float rgba_tmp_f[4];
766                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
767                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(rgba, rgba_tmp_f);
768                         }
769                 }
770                 else {
771                         if (rgba) {
772                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
773                         }
774                         else {
775                                 unsigned char rgba_tmp[4];
776                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
777                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(rgba_fp, rgba_tmp);
778                         }
779                 }
780         }
781         else {
782                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
783                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
784                 //if (xi<0 || xi>=ibuf->x  ||  yi<0 || yi>=ibuf->y) return 0;
785                 
786                 /* wrap */
787                 xi = ((int)(uv[0]*ibuf->x)) % ibuf->x;
788                 if (xi<0) xi += ibuf->x;
789                 yi = ((int)(uv[1]*ibuf->y)) % ibuf->y;
790                 if (yi<0) yi += ibuf->y;
791                 
792                 
793                 if (rgba) {
794                         if (ibuf->rect_float) {
795                                 float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
796                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(rgba, rgba_tmp_fp);
797                         }
798                         else {
799                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
800                         }
801                 }
802                 
803                 if (rgba_fp) {
804                         if (ibuf->rect_float) {
805                                 copy_v4_v4(rgba_fp, ((float *)ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
806                         }
807                         else {
808                                 char *tmp_ch= ((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
809                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(rgba_fp, tmp_ch);
810                         }
811                 }
812         }
813         return 1;
814 }
815
816 /* Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusuion test)
817  * return...
818  *  0   : no occlusion
819  * -1   : no occlusion but 2D intersection is true (avoid testing the other half of a quad)
820  *  1   : occluded
821  *  2   : occluded with w[3] weights set (need to know in some cases) */
822
823 static int project_paint_occlude_ptv(float pt[3], float v1[4], float v2[4], float v3[4], float w[3], int is_ortho)
824 {
825         /* if all are behind us, return false */
826         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
827                 return 0;
828                 
829         /* do a 2D point in try intersection */
830         if (!isect_point_tri_v2(pt, v1, v2, v3))
831                 return 0; /* we know there is  */
832         
833
834         /* From here on we know there IS an intersection */
835         /* if ALL of the verts are infront of us then we know it intersects ? */
836         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
837                 return 1;
838         }
839         else {
840                 /* we intersect? - find the exact depth at the point of intersection */
841                 /* Is this point is occluded by another face? */
842                 if (is_ortho) {
843                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
844                 }
845                 else {
846                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
847                 }
848         }
849         return -1;
850 }
851
852
853 static int project_paint_occlude_ptv_clip(
854                 const ProjPaintState *ps, const MFace *mf,
855                 float pt[3], float v1[4], float v2[4], float v3[4],
856                 const int side )
857 {
858         float w[3], wco[3];
859         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, ps->is_ortho);
860
861         if (ret <= 0)
862                 return ret;
863
864         if (ret==1) { /* weights not calculated */
865                 if (ps->is_ortho)       barycentric_weights_v2(v1, v2, v3, pt, w);
866                 else                            barycentric_weights_v2_persp(v1, v2, v3, pt, w);
867         }
868
869         /* Test if we're in the clipped area, */
870         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);
871         else            interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
872         
873         if (!ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
874                 return 1;
875         }
876         
877         return -1;
878 }
879
880
881 /* Check if a screenspace location is occluded by any other faces
882  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
883  * and dosn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
884 static int project_bucket_point_occluded(const ProjPaintState *ps, LinkNode *bucketFace, const int orig_face, float pixelScreenCo[4])
885 {
886         MFace *mf;
887         int face_index;
888         int isect_ret;
889         float w[3]; /* not needed when clipping */
890         const short do_clip= ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
891         
892         /* we could return 0 for 1 face buckets, as long as this function assumes
893          * that the point its testing is only every originated from an existing face */
894
895         for (; bucketFace; bucketFace = bucketFace->next) {
896                 face_index = GET_INT_FROM_POINTER(bucketFace->link);
897
898                 if (orig_face != face_index) {
899                         mf = ps->dm_mface + face_index;
900                         if (do_clip)
901                                 isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], 0);
902                         else
903                                 isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], w, ps->is_ortho);
904
905                         /* Note, if isect_ret==-1 then we don't want to test the other side of the quad */
906                         if (isect_ret==0 && mf->v4) {
907                                 if (do_clip)
908                                         isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], 1);
909                                 else
910                                         isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], w, ps->is_ortho);
911                         }
912                         if (isect_ret>=1) {
913                                 /* TODO - we may want to cache the first hit,
914                                  * it is not possible to swap the face order in the list anymore */
915                                 return 1;
916                         }
917                 }
918         }
919         return 0;
920 }
921
922 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
923  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
924 #define ISECT_TRUE 1
925 #define ISECT_TRUE_P1 2
926 #define ISECT_TRUE_P2 3
927 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
928 {
929         float y_diff;
930         
931         if (y_level==p1[1]) { /* are we touching the first point? - no interpolation needed */
932                 *x_isect = p1[0];
933                 return ISECT_TRUE_P1;
934         }
935         if (y_level==p2[1]) { /* are we touching the second point? - no interpolation needed */
936                 *x_isect = p2[0];
937                 return ISECT_TRUE_P2;
938         }
939         
940         y_diff= fabsf(p1[1]-p2[1]); /* yuck, horizontal line, we cant do much here */
941         
942         if (y_diff < 0.000001f) {
943                 *x_isect = (p1[0]+p2[0]) * 0.5f;
944                 return ISECT_TRUE;              
945         }
946         
947         if (p1[1] > y_level && p2[1] < y_level) {
948                 *x_isect = (p2[0]*(p1[1]-y_level) + p1[0]*(y_level-p2[1])) / y_diff;  /*(p1[1]-p2[1]);*/
949                 return ISECT_TRUE;
950         }
951         else if (p1[1] < y_level && p2[1] > y_level) {
952                 *x_isect = (p2[0]*(y_level-p1[1]) + p1[0]*(p2[1]-y_level)) / y_diff;  /*(p2[1]-p1[1]);*/
953                 return ISECT_TRUE;
954         }
955         else {
956                 return 0;
957         }
958 }
959
960 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
961 {
962         float x_diff;
963         
964         if (x_level==p1[0]) { /* are we touching the first point? - no interpolation needed */
965                 *y_isect = p1[1];
966                 return ISECT_TRUE_P1;
967         }
968         if (x_level==p2[0]) { /* are we touching the second point? - no interpolation needed */
969                 *y_isect = p2[1];
970                 return ISECT_TRUE_P2;
971         }
972         
973         x_diff= fabsf(p1[0]-p2[0]); /* yuck, horizontal line, we cant do much here */
974         
975         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
976                 *y_isect = (p1[0]+p2[0]) * 0.5f;
977                 return ISECT_TRUE;              
978         }
979         
980         if (p1[0] > x_level && p2[0] < x_level) {
981                 *y_isect = (p2[1]*(p1[0]-x_level) + p1[1]*(x_level-p2[0])) / x_diff; /*(p1[0]-p2[0]);*/
982                 return ISECT_TRUE;
983         }
984         else if (p1[0] < x_level && p2[0] > x_level) {
985                 *y_isect = (p2[1]*(x_level-p1[0]) + p1[1]*(p2[0]-x_level)) / x_diff; /*(p2[0]-p1[0]);*/
986                 return ISECT_TRUE;
987         }
988         else {
989                 return 0;
990         }
991 }
992
993 /* simple func use for comparing UV locations to check if there are seams.
994  * Its possible this gives incorrect results, when the UVs for 1 face go into the next 
995  * tile, but do not do this for the adjacent face, it could return a false positive.
996  * This is so unlikely that Id not worry about it. */
997 #ifndef PROJ_DEBUG_NOSEAMBLEED
998 static int cmp_uv(const float vec2a[2], const float vec2b[2])
999 {
1000         /* if the UV's are not between 0.0 and 1.0 */
1001         float xa = (float)fmodf(vec2a[0], 1.0f);
1002         float ya = (float)fmodf(vec2a[1], 1.0f);
1003         
1004         float xb = (float)fmodf(vec2b[0], 1.0f);
1005         float yb = (float)fmodf(vec2b[1], 1.0f);        
1006         
1007         if (xa < 0.0f) xa += 1.0f;
1008         if (ya < 0.0f) ya += 1.0f;
1009         
1010         if (xb < 0.0f) xb += 1.0f;
1011         if (yb < 0.0f) yb += 1.0f;
1012         
1013         return ((fabsf(xa-xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya-yb) < PROJ_GEOM_TOLERANCE)) ? 1:0;
1014 }
1015 #endif
1016
1017 /* set min_px and max_px to the image space bounds of the UV coords 
1018  * return zero if there is no area in the returned rectangle */
1019 #ifndef PROJ_DEBUG_NOSEAMBLEED
1020 static int pixel_bounds_uv(
1021                 const float uv1[2], const float uv2[2], const float uv3[2], const float uv4[2],
1022                 rcti *bounds_px,
1023                 const int ibuf_x, const int ibuf_y,
1024                 int is_quad
1025 ) {
1026         float min_uv[2], max_uv[2]; /* UV bounds */
1027         
1028         INIT_MINMAX2(min_uv, max_uv);
1029         
1030         DO_MINMAX2(uv1, min_uv, max_uv);
1031         DO_MINMAX2(uv2, min_uv, max_uv);
1032         DO_MINMAX2(uv3, min_uv, max_uv);
1033         if (is_quad)
1034                 DO_MINMAX2(uv4, min_uv, max_uv);
1035         
1036         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
1037         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
1038         
1039         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) +1;
1040         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) +1;
1041         
1042         /*printf("%d %d %d %d \n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
1043         
1044         /* face uses no UV area when quantized to pixels? */
1045         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
1046 }
1047 #endif
1048
1049 static int pixel_bounds_array(float (* uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
1050 {
1051         float min_uv[2], max_uv[2]; /* UV bounds */
1052         
1053         if (tot==0) {
1054                 return 0;
1055         }
1056         
1057         INIT_MINMAX2(min_uv, max_uv);
1058         
1059         while (tot--) {
1060                 DO_MINMAX2((*uv), min_uv, max_uv);
1061                 uv++;
1062         }
1063         
1064         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
1065         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
1066         
1067         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) +1;
1068         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) +1;
1069         
1070         /*printf("%d %d %d %d \n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
1071         
1072         /* face uses no UV area when quantized to pixels? */
1073         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
1074 }
1075
1076 #ifndef PROJ_DEBUG_NOSEAMBLEED
1077
1078 /* This function returns 1 if this face has a seam along the 2 face-vert indices
1079  * 'orig_i1_fidx' and 'orig_i2_fidx' */
1080 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)
1081 {
1082         LinkNode *node;
1083         int face_index;
1084         unsigned int i1, i2;
1085         int i1_fidx = -1, i2_fidx = -1; /* index in face */
1086         MFace *mf;
1087         MTFace *tf;
1088         const MFace *orig_mf = ps->dm_mface + orig_face;  
1089         const MTFace *orig_tf = ps->dm_mtface + orig_face;
1090         
1091         /* vert indices from face vert order indices */
1092         i1 = (*(&orig_mf->v1 + orig_i1_fidx));
1093         i2 = (*(&orig_mf->v1 + orig_i2_fidx));
1094         
1095         for (node = ps->vertFaces[i1]; node; node = node->next) {
1096                 face_index = GET_INT_FROM_POINTER(node->link);
1097
1098                 if (face_index != orig_face) {
1099                         mf = ps->dm_mface + face_index;
1100                         /* could check if the 2 faces images match here,
1101                          * but then there wouldn't be a way to return the opposite face's info */
1102                         
1103                         
1104                         /* We need to know the order of the verts in the adjacent face 
1105                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
1106                         if              (mf->v1==i1)                    i1_fidx = 0;
1107                         else if (mf->v2==i1)                    i1_fidx = 1;
1108                         else if (mf->v3==i1)                    i1_fidx = 2;
1109                         else if (mf->v4 && mf->v4==i1)  i1_fidx = 3;
1110                         
1111                         if              (mf->v1==i2)                    i2_fidx = 0;
1112                         else if (mf->v2==i2)                    i2_fidx = 1;
1113                         else if (mf->v3==i2)                    i2_fidx = 2;
1114                         else if (mf->v4 && mf->v4==i2)  i2_fidx = 3;
1115                         
1116                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
1117                         if (i2_fidx != -1) {
1118                                 Image *tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
1119                                 Image *orig_tpage = project_paint_face_image(ps, ps->dm_mtface, orig_face);
1120
1121                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
1122                                 tf = ps->dm_mtface + face_index;
1123                                 
1124                                 /* set up the other face */
1125                                 *other_face = face_index;
1126                                 *orig_fidx = (i1_fidx < i2_fidx) ? i1_fidx : i2_fidx;
1127                                 
1128                                 /* first test if they have the same image */
1129                                 if (    (orig_tpage == tpage) &&
1130                                                 cmp_uv(orig_tf->uv[orig_i1_fidx], tf->uv[i1_fidx]) &&
1131                                                 cmp_uv(orig_tf->uv[orig_i2_fidx], tf->uv[i2_fidx]) )
1132                                 {
1133                                         // printf("SEAM (NONE)\n");
1134                                         return 0;
1135                                         
1136                                 }
1137                                 else {
1138                                         // printf("SEAM (UV GAP)\n");
1139                                         return 1;
1140                                 }
1141                         }
1142                 }
1143         }
1144         // printf("SEAM (NO FACE)\n");
1145         *other_face = -1;
1146         return 1;
1147 }
1148
1149 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
1150  * since the outset coords are a margin that keep an even distance from the original UV's,
1151  * note that the image aspect is taken into account */
1152 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)
1153 {
1154         float a1, a2, a3, a4=0.0f;
1155         float puv[4][2]; /* pixelspace uv's */
1156         float no1[2], no2[2], no3[2], no4[2]; /* normals */
1157         float dir1[2], dir2[2], dir3[2], dir4[2];
1158         float ibuf_inv[2];
1159
1160         ibuf_inv[0]= 1.0f / (float)ibuf_x;
1161         ibuf_inv[1]= 1.0f / (float)ibuf_y;
1162
1163         /* make UV's in pixel space so we can */
1164         puv[0][0] = orig_uv[0][0] * ibuf_x;
1165         puv[0][1] = orig_uv[0][1] * ibuf_y;
1166         
1167         puv[1][0] = orig_uv[1][0] * ibuf_x;
1168         puv[1][1] = orig_uv[1][1] * ibuf_y;
1169         
1170         puv[2][0] = orig_uv[2][0] * ibuf_x;
1171         puv[2][1] = orig_uv[2][1] * ibuf_y;
1172         
1173         if (is_quad) {
1174                 puv[3][0] = orig_uv[3][0] * ibuf_x;
1175                 puv[3][1] = orig_uv[3][1] * ibuf_y;
1176         }
1177         
1178         /* face edge directions */
1179         sub_v2_v2v2(dir1, puv[1], puv[0]);
1180         sub_v2_v2v2(dir2, puv[2], puv[1]);
1181         normalize_v2(dir1);
1182         normalize_v2(dir2);
1183         
1184         if (is_quad) {
1185                 sub_v2_v2v2(dir3, puv[3], puv[2]);
1186                 sub_v2_v2v2(dir4, puv[0], puv[3]);
1187                 normalize_v2(dir3);
1188                 normalize_v2(dir4);
1189         }
1190         else {
1191                 sub_v2_v2v2(dir3, puv[0], puv[2]);
1192                 normalize_v2(dir3);
1193         }
1194
1195         /* TODO - angle_normalized_v2v2(...) * (M_PI/180.0f)
1196          * This is incorrect. Its already given radians but without it wont work.
1197          * need to look into a fix - campbell */
1198         if (is_quad) {
1199                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir4, dir1) * ((float)M_PI/180.0f));
1200                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI/180.0f));
1201                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI/180.0f));
1202                 a4 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir4) * ((float)M_PI/180.0f));
1203         }
1204         else {
1205                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir1) * ((float)M_PI/180.0f));
1206                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI/180.0f));
1207                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI/180.0f));
1208         }
1209         
1210         if (is_quad) {
1211                 sub_v2_v2v2(no1, dir4, dir1);
1212                 sub_v2_v2v2(no2, dir1, dir2);
1213                 sub_v2_v2v2(no3, dir2, dir3);
1214                 sub_v2_v2v2(no4, dir3, dir4);
1215                 normalize_v2(no1);
1216                 normalize_v2(no2);
1217                 normalize_v2(no3);
1218                 normalize_v2(no4);
1219                 mul_v2_fl(no1, a1*scaler);
1220                 mul_v2_fl(no2, a2*scaler);
1221                 mul_v2_fl(no3, a3*scaler);
1222                 mul_v2_fl(no4, a4*scaler);
1223                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1224                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1225                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1226                 add_v2_v2v2(outset_uv[3], puv[3], no4);
1227                 mul_v2_v2(outset_uv[0], ibuf_inv);
1228                 mul_v2_v2(outset_uv[1], ibuf_inv);
1229                 mul_v2_v2(outset_uv[2], ibuf_inv);
1230                 mul_v2_v2(outset_uv[3], ibuf_inv);
1231         }
1232         else {
1233                 sub_v2_v2v2(no1, dir3, dir1);
1234                 sub_v2_v2v2(no2, dir1, dir2);
1235                 sub_v2_v2v2(no3, dir2, dir3);
1236                 normalize_v2(no1);
1237                 normalize_v2(no2);
1238                 normalize_v2(no3);
1239                 mul_v2_fl(no1, a1*scaler);
1240                 mul_v2_fl(no2, a2*scaler);
1241                 mul_v2_fl(no3, a3*scaler);
1242                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1243                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1244                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1245
1246                 mul_v2_v2(outset_uv[0], ibuf_inv);
1247                 mul_v2_v2(outset_uv[1], ibuf_inv);
1248                 mul_v2_v2(outset_uv[2], ibuf_inv);
1249         }
1250 }
1251
1252 /* 
1253  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1254  * 1<<i - where i is (0-3) 
1255  * 
1256  * If we're multithreadng, make sure threads are locked when this is called
1257  */
1258 static void project_face_seams_init(const ProjPaintState *ps, const int face_index, const int is_quad)
1259 {
1260         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1261         int fidx1 = is_quad ? 3 : 2;
1262         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 */
1263         
1264         do {
1265                 if ((ps->faceSeamFlags[face_index] & (1<<fidx1|16<<fidx1)) == 0) {
1266                         if (check_seam(ps, face_index, fidx1, fidx2, &other_face, &other_fidx)) {
1267                                 ps->faceSeamFlags[face_index] |= 1<<fidx1;
1268                                 if (other_face != -1)
1269                                         ps->faceSeamFlags[other_face] |= 1<<other_fidx;
1270                         }
1271                         else {
1272                                 ps->faceSeamFlags[face_index] |= 16<<fidx1;
1273                                 if (other_face != -1)
1274                                         ps->faceSeamFlags[other_face] |= 16<<other_fidx; /* second 4 bits for disabled */
1275                         }
1276                 }
1277                 
1278                 fidx2 = fidx1;
1279         } while (fidx1--);
1280 }
1281 #endif // PROJ_DEBUG_NOSEAMBLEED
1282
1283
1284 /* Converts a UV location to a 3D screenspace location
1285  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1286  * 
1287  * This is used for finding a pixels location in screenspace for painting */
1288 static void screen_px_from_ortho(
1289                 float uv[2],
1290                 float v1co[3], float v2co[3], float v3co[3], /* Screenspace coords */
1291                 float uv1co[2], float uv2co[2], float uv3co[2],
1292                 float pixelScreenCo[4],
1293                 float w[3])
1294 {
1295         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1296         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1297 }
1298
1299 /* same as screen_px_from_ortho except we need to take into account
1300  * the perspective W coord for each vert */
1301 static void screen_px_from_persp(
1302                 float uv[2],
1303                 float v1co[4], float v2co[4], float v3co[4], /* screenspace coords */
1304                 float uv1co[2], float uv2co[2], float uv3co[2],
1305                 float pixelScreenCo[4],
1306                 float w[3])
1307 {
1308
1309         float wtot_inv, wtot;
1310         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1311         
1312         /* re-weight from the 4th coord of each screen vert */
1313         w[0] *= v1co[3];
1314         w[1] *= v2co[3];
1315         w[2] *= v3co[3];
1316         
1317         wtot = w[0]+w[1]+w[2];
1318         
1319         if (wtot > 0.0f) {
1320                 wtot_inv = 1.0f / wtot;
1321                 w[0] *= wtot_inv;
1322                 w[1] *= wtot_inv;
1323                 w[2] *= wtot_inv;
1324         }
1325         else {
1326                 w[0] = w[1] = w[2] = 1.0f/3.0f; /* dummy values for zero area face */
1327         }
1328         /* done re-weighting */
1329         
1330         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1331 }
1332
1333 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])
1334 {
1335         float *uvCo1, *uvCo2, *uvCo3;
1336         float uv_other[2], x, y;
1337         
1338         uvCo1 =  (float *)tf_other->uv[0];
1339         if (side==1) {
1340                 uvCo2 =  (float *)tf_other->uv[2];
1341                 uvCo3 =  (float *)tf_other->uv[3];
1342         }
1343         else {
1344                 uvCo2 =  (float *)tf_other->uv[1];
1345                 uvCo3 =  (float *)tf_other->uv[2];
1346         }
1347         
1348         interp_v2_v2v2v2(uv_other, uvCo1, uvCo2, uvCo3, (float*)w);
1349         
1350         /* use */
1351         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1352         
1353         
1354         if (ibuf_other->rect_float) { /* from float to float */
1355                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1356         }
1357         else { /* from char to float */
1358                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1359         }
1360                 
1361 }
1362
1363 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1364 static float project_paint_uvpixel_mask(
1365                 const ProjPaintState *ps,
1366                 const int face_index,
1367                 const int side,
1368                 const float w[3])
1369 {
1370         float mask;
1371         
1372         /* Image Mask */
1373         if (ps->do_layer_stencil) {
1374                 /* another UV maps image is masking this one's */
1375                 ImBuf *ibuf_other;
1376                 Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_stencil, face_index);
1377                 const MTFace *tf_other = ps->dm_mtface_stencil + face_index;
1378                 
1379                 if (other_tpage && (ibuf_other = BKE_image_get_ibuf(other_tpage, NULL))) {
1380                         /* BKE_image_get_ibuf - TODO - this may be slow */
1381                         unsigned char rgba_ub[4];
1382                         float rgba_f[4];
1383                         
1384                         project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, rgba_f);
1385                         
1386                         if (ibuf_other->rect_float) { /* from float to float */
1387                                 mask = ((rgba_f[0]+rgba_f[1]+rgba_f[2])/3.0f) * rgba_f[3];
1388                         }
1389                         else { /* from char to float */
1390                                 mask = ((rgba_ub[0]+rgba_ub[1]+rgba_ub[2])/(256*3.0f)) * (rgba_ub[3]/256.0f);
1391                         }
1392                         
1393                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1394                                 mask = (1.0f - mask);
1395
1396                         if (mask == 0.0f) {
1397                                 return 0.0f;
1398                         }
1399                 }
1400                 else {
1401                         return 0.0f;
1402                 }
1403         }
1404         else {
1405                 mask = 1.0f;
1406         }
1407         
1408         /* calculate mask */
1409         if (ps->do_mask_normal) {
1410                 MFace *mf = ps->dm_mface + face_index;
1411                 short *no1, *no2, *no3;
1412                 float no[3], angle;
1413                 no1 = ps->dm_mvert[mf->v1].no;
1414                 if (side==1) {
1415                         no2 = ps->dm_mvert[mf->v3].no;
1416                         no3 = ps->dm_mvert[mf->v4].no;
1417                 }
1418                 else {
1419                         no2 = ps->dm_mvert[mf->v2].no;
1420                         no3 = ps->dm_mvert[mf->v3].no;
1421                 }
1422                 
1423                 no[0] = w[0]*no1[0] + w[1]*no2[0] + w[2]*no3[0];
1424                 no[1] = w[0]*no1[1] + w[1]*no2[1] + w[2]*no3[1];
1425                 no[2] = w[0]*no1[2] + w[1]*no2[2] + w[2]*no3[2];
1426                 normalize_v3(no);
1427                 
1428                 /* now we can use the normal as a mask */
1429                 if (ps->is_ortho) {
1430                         angle = angle_normalized_v3v3((float *)ps->viewDir, no);
1431                 }
1432                 else {
1433                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1434                         float viewDirPersp[3];
1435                         float *co1, *co2, *co3;
1436                         co1 = ps->dm_mvert[mf->v1].co;
1437                         if (side==1) {
1438                                 co2 = ps->dm_mvert[mf->v3].co;
1439                                 co3 = ps->dm_mvert[mf->v4].co;
1440                         }
1441                         else {
1442                                 co2 = ps->dm_mvert[mf->v2].co;
1443                                 co3 = ps->dm_mvert[mf->v3].co;
1444                         }
1445
1446                         /* Get the direction from the viewPoint to the pixel and normalize */
1447                         viewDirPersp[0] = (ps->viewPos[0] - (w[0]*co1[0] + w[1]*co2[0] + w[2]*co3[0]));
1448                         viewDirPersp[1] = (ps->viewPos[1] - (w[0]*co1[1] + w[1]*co2[1] + w[2]*co3[1]));
1449                         viewDirPersp[2] = (ps->viewPos[2] - (w[0]*co1[2] + w[1]*co2[2] + w[2]*co3[2]));
1450                         normalize_v3(viewDirPersp);
1451                         
1452                         angle = angle_normalized_v3v3(viewDirPersp, no);
1453                 }
1454                 
1455                 if (angle >= ps->normal_angle) {
1456                         return 0.0f; /* outsize the normal limit*/
1457                 }
1458                 else if (angle > ps->normal_angle_inner) {
1459                         mask *= (ps->normal_angle - angle) / ps->normal_angle_range;
1460                 } /* otherwise no mask normal is needed, were within the limit */
1461         }
1462         
1463         // This only works when the opacity dosnt change while painting, stylus pressure messes with this
1464         // so don't use it.
1465         // if (ps->is_airbrush==0) mask *= brush_alpha(ps->brush);
1466         
1467         return mask;
1468 }
1469
1470 /* run this function when we know a bucket's, face's pixel can be initialized,
1471  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1472 static ProjPixel *project_paint_uvpixel_init(
1473                 const ProjPaintState *ps,
1474                 MemArena *arena,
1475                 const ImBuf *ibuf,
1476                 short x_px, short y_px,
1477                 const float mask,
1478                 const int face_index,
1479                 const int image_index,
1480                 const float pixelScreenCo[4],
1481                 const int side,
1482                 const float w[3])
1483 {
1484         ProjPixel *projPixel;
1485         short size;
1486         
1487         /* wrap pixel location */
1488         x_px = x_px % ibuf->x;
1489         if (x_px<0) x_px += ibuf->x;
1490         y_px = y_px % ibuf->y;
1491         if (y_px<0) y_px += ibuf->y;
1492         
1493         if (ps->tool==PAINT_TOOL_CLONE) {
1494                 size = sizeof(ProjPixelClone);
1495         }
1496         else if (ps->tool==PAINT_TOOL_SMEAR) {
1497                 size = sizeof(ProjPixelClone);
1498         }
1499         else {
1500                 size = sizeof(ProjPixel);
1501         }
1502         
1503         projPixel = (ProjPixel *)BLI_memarena_alloc(arena, size);
1504         //memset(projPixel, 0, size);
1505         
1506         if (ibuf->rect_float) {
1507                 projPixel->pixel.f_pt = (float *)ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1508                 projPixel->origColor.f[0] = projPixel->newColor.f[0] = projPixel->pixel.f_pt[0];  
1509                 projPixel->origColor.f[1] = projPixel->newColor.f[1] = projPixel->pixel.f_pt[1];  
1510                 projPixel->origColor.f[2] = projPixel->newColor.f[2] = projPixel->pixel.f_pt[2];  
1511                 projPixel->origColor.f[3] = projPixel->newColor.f[3] = projPixel->pixel.f_pt[3];  
1512         }
1513         else {
1514                 projPixel->pixel.ch_pt = ((unsigned char *)ibuf->rect + ((x_px + y_px * ibuf->x) * 4));
1515                 projPixel->origColor.uint = projPixel->newColor.uint = *projPixel->pixel.uint_pt;
1516         }
1517         
1518         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1519         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1520         
1521         projPixel->x_px = x_px;
1522         projPixel->y_px = y_px;
1523         
1524         projPixel->mask = (unsigned short)(mask * 65535);
1525         projPixel->mask_max = 0;
1526         
1527         /* which bounding box cell are we in?, needed for undo */
1528         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1529                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1530         
1531         /* done with view3d_project_float inline */
1532         if (ps->tool==PAINT_TOOL_CLONE) {
1533                 if (ps->dm_mtface_clone) {
1534                         ImBuf *ibuf_other;
1535                         Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_clone, face_index);
1536                         const MTFace *tf_other = ps->dm_mtface_clone + face_index;
1537                         
1538                         if (other_tpage && (ibuf_other = BKE_image_get_ibuf(other_tpage, NULL))) {
1539                                 /* BKE_image_get_ibuf - TODO - this may be slow */
1540                                 
1541                                 if (ibuf->rect_float) {
1542                                         if (ibuf_other->rect_float) { /* from float to float */
1543                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1544                                         }
1545                                         else { /* from char to float */
1546                                                 unsigned char rgba_ub[4];
1547                                                 project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, NULL);
1548                                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(((ProjPixelClone *)projPixel)->clonepx.f, rgba_ub);
1549                                         }
1550                                 }
1551                                 else {
1552                                         if (ibuf_other->rect_float) { /* float to char */
1553                                                 float rgba[4];
1554                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, rgba);
1555                                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(((ProjPixelClone *)projPixel)->clonepx.ch, rgba)
1556                                         }
1557                                         else { /* char to char */
1558                                                 project_face_pixel(tf_other, ibuf_other, w, side, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1559                                         }
1560                                 }
1561                         }
1562                         else {
1563                                 if (ibuf->rect_float) {
1564                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1565                                 }
1566                                 else {
1567                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1568                                 }
1569                         }
1570                         
1571                 }
1572                 else {
1573                         float co[2];
1574                         sub_v2_v2v2(co, projPixel->projCoSS, (float *)ps->cloneOffset);
1575                         
1576                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1577                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1578                         if (ibuf->rect_float) {
1579                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1580                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1581                                 }
1582                         }
1583                         else {
1584                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1585                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1586                                 }
1587                         }
1588                 }
1589         }
1590         
1591 #ifdef PROJ_DEBUG_PAINT
1592         if (ibuf->rect_float)   projPixel->pixel.f_pt[0] = 0;
1593         else                                    projPixel->pixel.ch_pt[0] = 0;
1594 #endif
1595         projPixel->image_index = image_index;
1596         
1597         return projPixel;
1598 }
1599
1600 static int line_clip_rect2f(
1601                 rctf *rect,
1602                 const float l1[2], const float l2[2],
1603                 float l1_clip[2], float l2_clip[2])
1604 {
1605         /* first account for horizontal, then vertical lines */
1606         /* horiz */
1607         if (fabsf(l1[1]-l2[1]) < PROJ_GEOM_TOLERANCE) {
1608                 /* is the line out of range on its Y axis? */
1609                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1610                         return 0;
1611                 }
1612                 /* line is out of range on its X axis */
1613                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1614                         return 0;
1615                 }
1616                 
1617                 
1618                 if (fabsf(l1[0]-l2[0]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1619                         if (BLI_in_rctf(rect, l1[0], l1[1])) {
1620                                 copy_v2_v2(l1_clip, l1);
1621                                 copy_v2_v2(l2_clip, l2);
1622                                 return 1;
1623                         }
1624                         else {
1625                                 return 0;
1626                         }
1627                 }
1628                 
1629                 copy_v2_v2(l1_clip, l1);
1630                 copy_v2_v2(l2_clip, l2);
1631                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1632                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1633                 return 1;
1634         }
1635         else if (fabsf(l1[0]-l2[0]) < PROJ_GEOM_TOLERANCE) {
1636                 /* is the line out of range on its X axis? */
1637                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1638                         return 0;
1639                 }
1640                 
1641                 /* line is out of range on its Y axis */
1642                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1643                         return 0;
1644                 }
1645                 
1646                 if (fabsf(l1[1]-l2[1]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1647                         if (BLI_in_rctf(rect, l1[0], l1[1])) {
1648                                 copy_v2_v2(l1_clip, l1);
1649                                 copy_v2_v2(l2_clip, l2);
1650                                 return 1;
1651                         }
1652                         else {
1653                                 return 0;
1654                         }
1655                 }
1656                 
1657                 copy_v2_v2(l1_clip, l1);
1658                 copy_v2_v2(l2_clip, l2);
1659                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1660                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1661                 return 1;
1662         }
1663         else {
1664                 float isect;
1665                 short ok1 = 0;
1666                 short ok2 = 0;
1667                 
1668                 /* Done with vertical lines */
1669                 
1670                 /* are either of the points inside the rectangle ? */
1671                 if (BLI_in_rctf(rect, l1[0], l1[1])) {
1672                         copy_v2_v2(l1_clip, l1);
1673                         ok1 = 1;
1674                 }
1675                 
1676                 if (BLI_in_rctf(rect, l2[0], l2[1])) {
1677                         copy_v2_v2(l2_clip, l2);
1678                         ok2 = 1;
1679                 }
1680                 
1681                 /* line inside rect */
1682                 if (ok1 && ok2) return 1;
1683                 
1684                 /* top/bottom */
1685                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1686                         if (l1[1] < l2[1]) { /* line 1 is outside */
1687                                 l1_clip[0] = isect;
1688                                 l1_clip[1] = rect->ymin;
1689                                 ok1 = 1;
1690                         }
1691                         else {
1692                                 l2_clip[0] = isect;
1693                                 l2_clip[1] = rect->ymin;
1694                                 ok2 = 2;
1695                         }
1696                 }
1697                 
1698                 if (ok1 && ok2) return 1;
1699                 
1700                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1701                         if (l1[1] > l2[1]) { /* line 1 is outside */
1702                                 l1_clip[0] = isect;
1703                                 l1_clip[1] = rect->ymax;
1704                                 ok1 = 1;
1705                         }
1706                         else {
1707                                 l2_clip[0] = isect;
1708                                 l2_clip[1] = rect->ymax;
1709                                 ok2 = 2;
1710                         }
1711                 }
1712                 
1713                 if (ok1 && ok2) return 1;
1714                 
1715                 /* left/right */
1716                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1717                         if (l1[0] < l2[0]) { /* line 1 is outside */
1718                                 l1_clip[0] = rect->xmin;
1719                                 l1_clip[1] = isect;
1720                                 ok1 = 1;
1721                         }
1722                         else {
1723                                 l2_clip[0] = rect->xmin;
1724                                 l2_clip[1] = isect;
1725                                 ok2 = 2;
1726                         }
1727                 }
1728         
1729                 if (ok1 && ok2) return 1;
1730                 
1731                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1732                         if (l1[0] > l2[0]) { /* line 1 is outside */
1733                                 l1_clip[0] = rect->xmax;
1734                                 l1_clip[1] = isect;
1735                                 ok1 = 1;
1736                         }
1737                         else {
1738                                 l2_clip[0] = rect->xmax;
1739                                 l2_clip[1] = isect;
1740                                 ok2 = 2;
1741                         }
1742                 }
1743                 
1744                 if (ok1 && ok2) {
1745                         return 1;
1746                 }
1747                 else {
1748                         return 0;
1749                 }
1750         }
1751 }
1752
1753
1754
1755 /* scale the quad & tri about its center
1756  * scaling by PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1757  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces */
1758 #ifndef PROJ_DEBUG_NOSEAMBLEED
1759 static void scale_quad(float insetCos[4][3], float *origCos[4], const float inset)
1760 {
1761         float cent[3];
1762         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0] + origCos[3][0]) / 4.0f;
1763         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1] + origCos[3][1]) / 4.0f;
1764         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2] + origCos[3][2]) / 4.0f;
1765         
1766         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1767         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1768         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1769         sub_v3_v3v3(insetCos[3], origCos[3], cent);
1770         
1771         mul_v3_fl(insetCos[0], inset);
1772         mul_v3_fl(insetCos[1], inset);
1773         mul_v3_fl(insetCos[2], inset);
1774         mul_v3_fl(insetCos[3], inset);
1775         
1776         add_v3_v3(insetCos[0], cent);
1777         add_v3_v3(insetCos[1], cent);
1778         add_v3_v3(insetCos[2], cent);
1779         add_v3_v3(insetCos[3], cent);
1780 }
1781
1782
1783 static void scale_tri(float insetCos[4][3], float *origCos[4], const float inset)
1784 {
1785         float cent[3];
1786         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) / 3.0f;
1787         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) / 3.0f;
1788         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) / 3.0f;
1789         
1790         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1791         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1792         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1793         
1794         mul_v3_fl(insetCos[0], inset);
1795         mul_v3_fl(insetCos[1], inset);
1796         mul_v3_fl(insetCos[2], inset);
1797         
1798         add_v3_v3(insetCos[0], cent);
1799         add_v3_v3(insetCos[1], cent);
1800         add_v3_v3(insetCos[2], cent);
1801 }
1802 #endif //PROJ_DEBUG_NOSEAMBLEED
1803
1804 static float len_squared_v2v2_alt(const float *v1, const float v2_1, const float v2_2)
1805 {
1806         float x, y;
1807
1808         x = v1[0]-v2_1;
1809         y = v1[1]-v2_2;
1810         return x*x+y*y;
1811 }
1812
1813 /* note, use a squared value so we can use len_squared_v2v2
1814  * be sure that you have done a bounds check first or this may fail */
1815 /* only give bucket_bounds as an arg because we need it elsewhere */
1816 static int project_bucket_isect_circle(const float cent[2], const float radius_squared, rctf *bucket_bounds)
1817 {
1818          
1819         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect 
1820          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1821          * this is even less work then an intersection test
1822          */
1823 #if 0
1824         if (BLI_in_rctf(bucket_bounds, cent[0], cent[1]))
1825                 return 1;
1826 #endif
1827         
1828         if ( (bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1829              (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]) )
1830         {
1831                 return 1;
1832         }
1833         
1834         /* out of bounds left */
1835         if (cent[0] < bucket_bounds->xmin) {
1836                 /* lower left out of radius test */
1837                 if (cent[1] < bucket_bounds->ymin) {
1838                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1839                 } 
1840                 /* top left test */
1841                 else if (cent[1] > bucket_bounds->ymax) {
1842                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1843                 }
1844         }
1845         else if (cent[0] > bucket_bounds->xmax) {
1846                 /* lower right out of radius test */
1847                 if (cent[1] < bucket_bounds->ymin) {
1848                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1849                 } 
1850                 /* top right test */
1851                 else if (cent[1] > bucket_bounds->ymax) {
1852                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1853                 }
1854         }
1855         
1856         return 0;
1857 }
1858
1859
1860
1861 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1862  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1863  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1864  * (viewed from the side)
1865  * 
1866  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1867  * funcs that only account for points inside the triangle.
1868  * however switching back to this for ortho is always an option */
1869
1870 static void rect_to_uvspace_ortho(
1871                 rctf *bucket_bounds,
1872                 float *v1coSS, float *v2coSS, float *v3coSS,
1873                 float *uv1co, float *uv2co, float *uv3co,
1874                 float bucket_bounds_uv[4][2],
1875                 const int flip)
1876 {
1877         float uv[2];
1878         float w[3];
1879         
1880         /* get the UV space bounding box */
1881         uv[0] = bucket_bounds->xmax;
1882         uv[1] = bucket_bounds->ymin;
1883         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1884         interp_v2_v2v2v2(bucket_bounds_uv[flip?3:0], uv1co, uv2co, uv3co, w);
1885
1886         //uv[0] = bucket_bounds->xmax; // set above
1887         uv[1] = bucket_bounds->ymax;
1888         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1889         interp_v2_v2v2v2(bucket_bounds_uv[flip?2:1], uv1co, uv2co, uv3co, w);
1890
1891         uv[0] = bucket_bounds->xmin;
1892         //uv[1] = bucket_bounds->ymax; // set above
1893         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1894         interp_v2_v2v2v2(bucket_bounds_uv[flip?1:2], uv1co, uv2co, uv3co, w);
1895
1896         //uv[0] = bucket_bounds->xmin; // set above
1897         uv[1] = bucket_bounds->ymin;
1898         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1899         interp_v2_v2v2v2(bucket_bounds_uv[flip?0:3], uv1co, uv2co, uv3co, w);
1900 }
1901
1902 /* same as above but use barycentric_weights_v2_persp */
1903 static void rect_to_uvspace_persp(
1904                 rctf *bucket_bounds,
1905                 float *v1coSS, float *v2coSS, float *v3coSS,
1906                 float *uv1co, float *uv2co, float *uv3co,
1907                 float bucket_bounds_uv[4][2],
1908                 const int flip
1909         )
1910 {
1911         float uv[2];
1912         float w[3];
1913         
1914         /* get the UV space bounding box */
1915         uv[0] = bucket_bounds->xmax;
1916         uv[1] = bucket_bounds->ymin;
1917         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1918         interp_v2_v2v2v2(bucket_bounds_uv[flip?3:0], uv1co, uv2co, uv3co, w);
1919
1920         //uv[0] = bucket_bounds->xmax; // set above
1921         uv[1] = bucket_bounds->ymax;
1922         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1923         interp_v2_v2v2v2(bucket_bounds_uv[flip?2:1], uv1co, uv2co, uv3co, w);
1924
1925         uv[0] = bucket_bounds->xmin;
1926         //uv[1] = bucket_bounds->ymax; // set above
1927         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1928         interp_v2_v2v2v2(bucket_bounds_uv[flip?1:2], uv1co, uv2co, uv3co, w);
1929
1930         //uv[0] = bucket_bounds->xmin; // set above
1931         uv[1] = bucket_bounds->ymin;
1932         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1933         interp_v2_v2v2v2(bucket_bounds_uv[flip?0:3], uv1co, uv2co, uv3co, w);
1934 }
1935
1936 /* This works as we need it to but we can save a few steps and not use it */
1937
1938 #if 0
1939 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
1940 {
1941         float v1[2], v2[2];
1942         
1943         v1[0] = p1[0]-p2[0];    v1[1] = p1[1]-p2[1];
1944         v2[0] = p3[0]-p2[0];    v2[1] = p3[1]-p2[1];
1945         
1946         return -atan2(v1[0]*v2[1] - v1[1]*v2[0], v1[0]*v2[0]+v1[1]*v2[1]);
1947 }
1948 #endif
1949
1950 #define ISECT_1 (1)
1951 #define ISECT_2 (1<<1)
1952 #define ISECT_3 (1<<2)
1953 #define ISECT_4 (1<<3)
1954 #define ISECT_ALL3 ((1<<3)-1)
1955 #define ISECT_ALL4 ((1<<4)-1)
1956
1957 /* limit must be a fraction over 1.0f */
1958 static int IsectPT2Df_limit(float pt[2], float v1[2], float v2[2], float v3[2], float limit)
1959 {
1960         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;
1961 }
1962
1963 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
1964  * so we have the clipped UV's to do pixel intersection tests with 
1965  * */
1966 static int float_z_sort_flip(const void *p1, const void *p2)
1967 {
1968         return (((float *)p1)[2] < ((float *)p2)[2] ? 1:-1);
1969 }
1970
1971 static int float_z_sort(const void *p1, const void *p2)
1972 {
1973         return (((float *)p1)[2] < ((float *)p2)[2] ?-1:1);
1974 }
1975
1976 static void project_bucket_clip_face(
1977                 const int is_ortho,
1978                 rctf *bucket_bounds,
1979                 float *v1coSS, float *v2coSS, float *v3coSS,
1980                 float *uv1co, float *uv2co, float *uv3co,
1981                 float bucket_bounds_uv[8][2],
1982                 int *tot)
1983 {
1984         int inside_bucket_flag = 0;
1985         int inside_face_flag = 0;
1986         const int flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
1987         
1988         float bucket_bounds_ss[4][2];
1989
1990         /* get the UV space bounding box */
1991         inside_bucket_flag |= BLI_in_rctf(bucket_bounds, v1coSS[0], v1coSS[1]);
1992         inside_bucket_flag |= BLI_in_rctf(bucket_bounds, v2coSS[0], v2coSS[1])          << 1;
1993         inside_bucket_flag |= BLI_in_rctf(bucket_bounds, v3coSS[0], v3coSS[1])          << 2;
1994         
1995         if (inside_bucket_flag == ISECT_ALL3) {
1996                 /* all screenspace points are inside the bucket bounding box, this means we don't need to clip and can simply return the UVs */
1997                 if (flip) { /* facing the back? */
1998                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
1999                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2000                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
2001                 }
2002                 else {
2003                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
2004                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2005                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
2006                 }
2007                 
2008                 *tot = 3; 
2009                 return;
2010         }
2011         
2012         /* get the UV space bounding box */
2013         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
2014         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
2015         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
2016         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1+PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
2017         
2018         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
2019         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
2020         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1+PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
2021
2022         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
2023         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
2024         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1+PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
2025
2026         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
2027         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
2028         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1+PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
2029         
2030         if (inside_face_flag == ISECT_ALL4) {
2031                 /* bucket is totally inside the screenspace face, we can safely use weights */
2032                 
2033                 if (is_ortho)   rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2034                 else                    rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2035                 
2036                 *tot = 4;
2037                 return;
2038         }
2039         else {
2040                 /* The Complicated Case! 
2041                  * 
2042                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
2043                  * 
2044                  * we need to make a convex polyline from the intersection between the screenspace face
2045                  * and the bucket bounds.
2046                  * 
2047                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
2048                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
2049                  * do a correct clipping on both shapes. */
2050                 
2051                 
2052                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
2053                 
2054                 
2055                 
2056                 /* Maximum possible 6 intersections when using a rectangle and triangle */
2057                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
2058                 float v1_clipSS[2], v2_clipSS[2];
2059                 float w[3];
2060                 
2061                 /* calc center*/
2062                 float cent[2] = {0.0f, 0.0f};
2063                 /*float up[2] = {0.0f, 1.0f};*/
2064                 int i;
2065                 short doubles;
2066                 
2067                 (*tot) = 0;
2068                 
2069                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
2070                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
2071                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
2072                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
2073                 
2074                 if (inside_bucket_flag & ISECT_1) {     copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
2075                 if (inside_bucket_flag & ISECT_2) {     copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
2076                 if (inside_bucket_flag & ISECT_3) {     copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
2077                 
2078                 if ((inside_bucket_flag & (ISECT_1|ISECT_2)) != (ISECT_1|ISECT_2)) {
2079                         if (line_clip_rect2f(bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
2080                                 if ((inside_bucket_flag & ISECT_1)==0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2081                                 if ((inside_bucket_flag & ISECT_2)==0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2082                         }
2083                 }
2084                 
2085                 if ((inside_bucket_flag & (ISECT_2|ISECT_3)) != (ISECT_2|ISECT_3)) {
2086                         if (line_clip_rect2f(bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
2087                                 if ((inside_bucket_flag & ISECT_2)==0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2088                                 if ((inside_bucket_flag & ISECT_3)==0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2089                         }
2090                 }       
2091                 
2092                 if ((inside_bucket_flag & (ISECT_3|ISECT_1)) != (ISECT_3|ISECT_1)) {
2093                         if (line_clip_rect2f(bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
2094                                 if ((inside_bucket_flag & ISECT_3)==0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2095                                 if ((inside_bucket_flag & ISECT_1)==0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2096                         }
2097                 }
2098                 
2099                 
2100                 if ((*tot) < 3) { /* no intersections to speak of */
2101                         *tot = 0;
2102                         return;
2103                 }
2104         
2105                 /* now we have all points we need, collect their angles and sort them clockwise */
2106                 
2107                 for (i=0; i<(*tot); i++) {
2108                         cent[0] += isectVCosSS[i][0];
2109                         cent[1] += isectVCosSS[i][1];
2110                 }
2111                 cent[0] = cent[0] / (float)(*tot);
2112                 cent[1] = cent[1] / (float)(*tot);
2113                 
2114                 
2115                 
2116                 /* Collect angles for every point around the center point */
2117
2118                 
2119 #if 0   /* uses a few more cycles then the above loop */
2120                 for (i=0; i<(*tot); i++) {
2121                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
2122                 }
2123 #endif
2124
2125                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
2126                 v1_clipSS[1] = cent[1] + 1.0f;
2127                 
2128                 for (i=0; i<(*tot); i++) {
2129                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2130                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2131                         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]); 
2132                 }
2133                 
2134                 if (flip)       qsort(isectVCosSS, *tot, sizeof(float)*3, float_z_sort_flip);
2135                 else            qsort(isectVCosSS, *tot, sizeof(float)*3, float_z_sort);
2136                 
2137                 /* remove doubles */
2138                 /* first/last check */
2139                 if (fabsf(isectVCosSS[0][0]-isectVCosSS[(*tot)-1][0]) < PROJ_GEOM_TOLERANCE &&  fabsf(isectVCosSS[0][1]-isectVCosSS[(*tot)-1][1]) < PROJ_GEOM_TOLERANCE) {
2140                         (*tot)--;
2141                 }
2142                 
2143                 /* its possible there is only a few left after remove doubles */
2144                 if ((*tot) < 3) {
2145                         // printf("removed too many doubles A\n");
2146                         *tot = 0;
2147                         return;
2148                 }
2149                 
2150                 doubles = TRUE;
2151                 while (doubles==TRUE) {
2152                         doubles = FALSE;
2153                         for (i=1; i<(*tot); i++) {
2154                                 if (fabsf(isectVCosSS[i-1][0]-isectVCosSS[i][0]) < PROJ_GEOM_TOLERANCE &&
2155                                         fabsf(isectVCosSS[i-1][1]-isectVCosSS[i][1]) < PROJ_GEOM_TOLERANCE)
2156                                 {
2157                                         int j;
2158                                         for (j=i+1; j<(*tot); j++) {
2159                                                 isectVCosSS[j-1][0] = isectVCosSS[j][0]; 
2160                                                 isectVCosSS[j-1][1] = isectVCosSS[j][1]; 
2161                                         }
2162                                         doubles = TRUE; /* keep looking for more doubles */
2163                                         (*tot)--;
2164                                 }
2165                         }
2166                 }
2167                 
2168                 /* its possible there is only a few left after remove doubles */
2169                 if ((*tot) < 3) {
2170                         // printf("removed too many doubles B\n");
2171                         *tot = 0;
2172                         return;
2173                 }
2174                 
2175                 
2176                 if (is_ortho) {
2177                         for (i=0; i<(*tot); i++) {
2178                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2179                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2180                         }
2181                 }
2182                 else {
2183                         for (i=0; i<(*tot); i++) {
2184                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2185                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2186                         }
2187                 }
2188         }
2189
2190 #ifdef PROJ_DEBUG_PRINT_CLIP
2191         /* include this at the bottom of the above function to debug the output */
2192
2193         {
2194                 /* If there are ever any problems, */
2195                 float test_uv[4][2];
2196                 int i;
2197                 if (is_ortho)   rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2198                 else                            rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2199                 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]);
2200                 
2201                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2202                 
2203                 printf("[");
2204                 for (i=0; i < (*tot); i++) {
2205                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2206                 }
2207                 printf("]),\\\n");
2208         }
2209 #endif
2210 }
2211
2212 /*
2213  * # This script creates faces in a blender scene from printed data above.
2214  *
2215  * project_ls = [
2216  * ...(output from above block)...
2217  * ]
2218  *
2219  * from Blender import Scene, Mesh, Window, sys, Mathutils
2220  *
2221  * import bpy
2222  *
2223  * V = Mathutils.Vector
2224  *
2225  * def main():
2226  *     sce = bpy.data.scenes.active
2227  *     
2228  *     for item in project_ls:
2229  *         bb = item[0]
2230  *         uv = item[1]
2231  *         poly = item[2]
2232  *         
2233  *         me = bpy.data.meshes.new()
2234  *         ob = sce.objects.new(me)
2235  *         
2236  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2237  *         me.faces.extend([(0,1,2,3),])
2238  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2239  *         me.faces.extend([(4,5,6),])
2240  *         
2241  *         vs = [V(p).xyz for p in poly]
2242  *         print len(vs)
2243  *         l = len(me.verts)
2244  *         me.verts.extend(vs)
2245  *         
2246  *         i = l
2247  *         while i < len(me.verts):
2248  *             ii = i+1
2249  *             if ii==len(me.verts):
2250  *                 ii = l
2251  *             me.edges.extend([i, ii])
2252  *             i+=1
2253  * 
2254  * if __name__ == '__main__':
2255  *     main()
2256  */
2257
2258
2259 #undef ISECT_1
2260 #undef ISECT_2
2261 #undef ISECT_3
2262 #undef ISECT_4
2263 #undef ISECT_ALL3
2264 #undef ISECT_ALL4
2265
2266         
2267 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2268  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2269 static int IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2270 {
2271         int i;
2272         if (line_point_side_v2(uv[tot-1], uv[0], pt) < 0.0f)
2273                 return 0;
2274         
2275         for (i=1; i<tot; i++) {
2276                 if (line_point_side_v2(uv[i-1], uv[i], pt) < 0.0f)
2277                         return 0;
2278                 
2279         }
2280         
2281         return 1;
2282 }
2283 static int IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2284 {
2285         int i;
2286         int side = (line_point_side_v2(uv[tot-1], uv[0], pt) > 0.0f);
2287         
2288         for (i=1; i<tot; i++) {
2289                 if ((line_point_side_v2(uv[i-1], uv[i], pt) > 0.0f) != side)
2290                         return 0;
2291                 
2292         }
2293         
2294         return 1;
2295 }
2296
2297 /* One of the most important function for projectiopn painting, since it selects the pixels to be added into each bucket.
2298  * initialize pixels from this face where it intersects with the bucket_index, optionally initialize pixels for removing seams */
2299 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)
2300 {
2301         /* Projection vars, to get the 3D locations into screen space  */
2302         MemArena *arena = ps->arena_mt[thread_index];
2303         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2304         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2305         
2306         const MFace *mf = ps->dm_mface + face_index;
2307         const MTFace *tf = ps->dm_mtface + face_index;
2308         
2309         /* UV/pixel seeking data */
2310         int x; /* Image X-Pixel */
2311         int y;/* Image Y-Pixel */
2312         float mask;
2313         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2314         
2315         int side;
2316         float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to mf->v1,2,3 or mf->v1,3,4 */
2317         
2318         float *vCo[4]; /* vertex screenspace coords */
2319         
2320         float w[3], wco[3];
2321         
2322         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to tf->uv[0],1,2 or tf->uv[0],2,3 */
2323         float pixelScreenCo[4];
2324         
2325         rcti bounds_px; /* ispace bounds */
2326         /* vars for getting uvspace bounds */
2327         
2328         float tf_uv_pxoffset[4][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2329         float xhalfpx, yhalfpx;
2330         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2331         
2332         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2333         
2334         int i1, i2, i3;
2335         
2336         float uv_clip[8][2];
2337         int uv_clip_tot;
2338         const short is_ortho = ps->is_ortho;
2339         const short do_backfacecull = ps->do_backfacecull;
2340         const short do_clip= ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2341         
2342         vCo[0] = ps->dm_mvert[mf->v1].co;
2343         vCo[1] = ps->dm_mvert[mf->v2].co;
2344         vCo[2] = ps->dm_mvert[mf->v3].co;
2345         
2346         
2347         /* Use tf_uv_pxoffset instead of tf->uv so we can offset the UV half a pixel
2348          * this is done so we can avoid offseting all the pixels by 0.5 which causes
2349          * problems when wrapping negative coords */
2350         xhalfpx = (0.5f+   (PROJ_GEOM_TOLERANCE/3.0f)   ) / ibuf_xf;
2351         yhalfpx = (0.5f+   (PROJ_GEOM_TOLERANCE/4.0f)   ) / ibuf_yf;
2352         
2353         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2354          * Needed to add this offset since UV coords are often quads aligned to pixels.
2355          * In this case pixels can be exactly between 2 triangles causing nasty
2356          * artifacts.
2357          * 
2358          * This workaround can be removed and painting will still work on most cases
2359          * but since the first thing most people try is painting onto a quad- better make it work.
2360          */
2361
2362
2363
2364         tf_uv_pxoffset[0][0] = tf->uv[0][0] - xhalfpx;
2365         tf_uv_pxoffset[0][1] = tf->uv[0][1] - yhalfpx;
2366
2367         tf_uv_pxoffset[1][0] = tf->uv[1][0] - xhalfpx;
2368         tf_uv_pxoffset[1][1] = tf->uv[1][1] - yhalfpx;
2369         
2370         tf_uv_pxoffset[2][0] = tf->uv[2][0] - xhalfpx;
2371         tf_uv_pxoffset[2][1] = tf->uv[2][1] - yhalfpx;  
2372         
2373         if (mf->v4) {
2374                 vCo[3] = ps->dm_mvert[ mf->v4 ].co;
2375                 
2376                 tf_uv_pxoffset[3][0] = tf->uv[3][0] - xhalfpx;
2377                 tf_uv_pxoffset[3][1] = tf->uv[3][1] - yhalfpx;
2378                 side = 1;
2379         }
2380         else {
2381                 side = 0;
2382         }
2383         
2384         do {
2385                 if (side==1) {
2386                         i1=0; i2=2; i3=3;
2387                 }
2388                 else {
2389                         i1=0; i2=1; i3=2;
2390                 }
2391                 
2392                 uv1co = tf_uv_pxoffset[i1]; // was tf->uv[i1];
2393                 uv2co = tf_uv_pxoffset[i2]; // was tf->uv[i2];
2394                 uv3co = tf_uv_pxoffset[i3]; // was tf->uv[i3];
2395
2396                 v1coSS = ps->screenCoords[ (*(&mf->v1 + i1)) ];
2397                 v2coSS = ps->screenCoords[ (*(&mf->v1 + i2)) ];
2398                 v3coSS = ps->screenCoords[ (*(&mf->v1 + i3)) ];
2399                 
2400                 /* This funtion gives is a concave polyline in UV space from the clipped quad and tri*/
2401                 project_bucket_clip_face(
2402                                 is_ortho, bucket_bounds,
2403                                 v1coSS, v2coSS, v3coSS,
2404                                 uv1co, uv2co, uv3co,
2405                                 uv_clip, &uv_clip_tot
2406                 );
2407
2408                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2409 #if 0
2410                 if (uv_clip_tot>6) {
2411                         printf("this should never happen! %d\n", uv_clip_tot);
2412                 }
2413 #endif
2414
2415                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2416
2417                         if (clamp_u) {
2418                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2419                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2420                         }
2421
2422                         if (clamp_v) {
2423                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2424                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2425                         }
2426
2427                         /* clip face and */
2428                         
2429                         has_isect = 0;
2430                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2431                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2432                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2433
2434                                 has_x_isect = 0;
2435                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2436                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2437                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2438                                         
2439                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2440                                          * could check the poly direction but better to do this */
2441                                         if (    (do_backfacecull                && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2442                                                 (do_backfacecull==0             && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot))) {
2443                                                 
2444                                                 has_x_isect = has_isect = 1;
2445                                                 
2446                                                 if (is_ortho)   screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2447                                                 else                    screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2448                                                 
2449                                                 /* a pity we need to get the worldspace pixel location here */
2450                                                 if (do_clip) {
2451                                                         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);
2452                                                         if (ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2453                                                                 continue; /* Watch out that no code below this needs to run */
2454                                                         }
2455                                                 }
2456                                                 
2457                                                 /* Is this UV visible from the view? - raytrace */
2458                                                 /* project_paint_PickFace is less complex, use for testing */
2459                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == face_index) {
2460                                                 if (ps->do_occlude==0 || !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo)) {
2461                                                         
2462                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2463                                                         
2464                                                         if (mask > 0.0f) {
2465                                                                 BLI_linklist_prepend_arena(
2466                                                                         bucketPixelNodes,
2467                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index, image_index, pixelScreenCo, side, w),
2468                                                                         arena
2469                                                                 );
2470                                                         }
2471                                                 }
2472                                                 
2473                                         }
2474 //#if 0
2475                                         else if (has_x_isect) {
2476                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2477                                                 break;
2478                                         }
2479 //#endif
2480                                 }
2481                                 
2482                                 
2483 #if 0                   /* TODO - investigate why this dosnt work sometimes! it should! */
2484                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2485                                 if (has_x_isect==0 && has_isect) { 
2486                                         break;
2487                                 }
2488 #endif
2489                         }
2490                 }
2491         } while (side--);
2492
2493         
2494         
2495 #ifndef PROJ_DEBUG_NOSEAMBLEED
2496         if (ps->seam_bleed_px > 0.0f) {
2497                 int face_seam_flag;
2498                 
2499                 if (ps->thread_tot > 1)
2500                         BLI_lock_thread(LOCK_CUSTOM1); /* Other threads could be modifying these vars */
2501                 
2502                 face_seam_flag = ps->faceSeamFlags[face_index];
2503                 
2504                 /* are any of our edges un-initialized? */
2505                 if ((face_seam_flag & (PROJ_FACE_SEAM1|PROJ_FACE_NOSEAM1))==0 || 
2506                         (face_seam_flag & (PROJ_FACE_SEAM2|PROJ_FACE_NOSEAM2))==0 || 
2507                         (face_seam_flag & (PROJ_FACE_SEAM3|PROJ_FACE_NOSEAM3))==0 || 
2508                         (face_seam_flag & (PROJ_FACE_SEAM4|PROJ_FACE_NOSEAM4))==0
2509                 ) {
2510                         project_face_seams_init(ps, face_index, mf->v4);
2511                         face_seam_flag = ps->faceSeamFlags[face_index];
2512                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3, flag&PROJ_FACE_SEAM4);
2513                 }
2514                 
2515                 if ((face_seam_flag & (PROJ_FACE_SEAM1|PROJ_FACE_SEAM2|PROJ_FACE_SEAM3|PROJ_FACE_SEAM4))==0) {
2516                         
2517                         if (ps->thread_tot > 1)
2518                                 BLI_unlock_thread(LOCK_CUSTOM1); /* Other threads could be modifying these vars */
2519                         
2520                 }
2521                 else {
2522                         /* we have a seam - deal with it! */
2523                         
2524                         /* Now create new UV's for the seam face */
2525                         float (*outset_uv)[2] = ps->faceSeamUVs[face_index];
2526                         float insetCos[4][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2527
2528                         float fac;
2529                         float *vCoSS[4]; /* vertex screenspace coords */
2530                         
2531                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2532                         float edge_verts_inset_clip[2][3];
2533                         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 */
2534                         
2535                         float seam_subsection[4][2];
2536                         float fac1, fac2, ftot;
2537                         
2538                         
2539                         if (outset_uv[0][0]==FLT_MAX) /* first time initialize */
2540                                 uv_image_outset(tf_uv_pxoffset, outset_uv, ps->seam_bleed_px, ibuf->x, ibuf->y, mf->v4);
2541                         
2542                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2543                         if (ps->thread_tot > 1)
2544                                 BLI_unlock_thread(LOCK_CUSTOM1); /* Other threads could be modifying these vars */
2545                         
2546                         vCoSS[0] = ps->screenCoords[mf->v1];
2547                         vCoSS[1] = ps->screenCoords[mf->v2];
2548                         vCoSS[2] = ps->screenCoords[mf->v3];
2549                         if (mf->v4)
2550                                 vCoSS[3] = ps->screenCoords[ mf->v4 ];
2551                         
2552                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2553                         if (is_ortho) {
2554                                 if (mf->v4)     scale_quad(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2555                                 else            scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2556                         }
2557                         else {
2558                                 if (mf->v4)     scale_quad(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2559                                 else            scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2560                         }
2561                         
2562                         side = 0; /* for triangles this wont need to change */
2563                         
2564                         for (fidx1 = 0; fidx1 < (mf->v4 ? 4 : 3); fidx1++) {
2565                                 if (mf->v4)             fidx2 = (fidx1==3) ? 0 : fidx1+1; /* next fidx in the face (0,1,2,3) -> (1,2,3,0) */
2566                                 else                    fidx2 = (fidx1==2) ? 0 : fidx1+1; /* next fidx in the face (0,1,2) -> (1,2,0) */
2567                                 
2568                                 if (    (face_seam_flag & (1<<fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2569                                                 line_clip_rect2f(bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1])
2570                                 ) {
2571
2572                                         ftot = len_v2v2(vCoSS[fidx1], vCoSS[fidx2]); /* screenspace edge length */
2573                                         
2574                                         if (ftot > 0.0f) { /* avoid div by zero */
2575                                                 if (mf->v4) {
2576                                                         if (fidx1==2 || fidx2==2)       side= 1;
2577                                                         else                                            side= 0;
2578                                                 }
2579                                                 
2580                                                 fac1 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[0]) / ftot;
2581                                                 fac2 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[1]) / ftot;
2582                                                 
2583                                                 interp_v2_v2v2(seam_subsection[0], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac1);
2584                                                 interp_v2_v2v2(seam_subsection[1], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac2);
2585
2586                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2587                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2588                                                 
2589                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2590                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2591                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2592                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2593                                                 
2594
2595                                                 if (pixel_bounds_uv(seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3], &bounds_px, ibuf->x, ibuf->y, 1)) {
2596                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2597                                                         
2598                                                         has_isect = 0;
2599                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2600                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2601                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2602                                                                 
2603                                                                 has_x_isect = 0;
2604                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2605                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2606                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2607                                                                         
2608                                                                         /* test we're inside uvspace bucket and triangle bounds */
2609                                                                         if (isect_point_quad_v2(uv, seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3])) {
2610                                                                                 
2611                                                                                 /* We need to find the closest point along the face edge,
2612                                                                                  * getting the screen_px_from_*** wont work because our actual location
2613                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2614                                                                                  * our location on the side of the face's UV */
2615 #if 0
2616                                                                                 if (is_ortho)   screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2617                                                                                 else                                    screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2618 #endif
2619                                                                                 
2620                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2621                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2622                                                                                 
2623                                                                                 fac = line_point_factor_v2(uv, seam_subsection[0], seam_subsection[1]);
2624                                                                                 if (fac < 0.0f)         { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[0]); }
2625                                                                                 else if (fac > 1.0f)    { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[1]); }
2626                                                                                 else                            { interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac); }
2627                                                                                 
2628                                                                                 if (!is_ortho) {
2629                                                                                         pixelScreenCo[3] = 1.0f;
2630                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2631                                                                                         pixelScreenCo[0] = (float)(ps->winx/2.0f)+(ps->winx/2.0f)*pixelScreenCo[0]/pixelScreenCo[3];
2632                                                                                         pixelScreenCo[1] = (float)(ps->winy/2.0f)+(ps->winy/2.0f)*pixelScreenCo[1]/pixelScreenCo[3];
2633                                                                                         pixelScreenCo[2] = pixelScreenCo[2]/pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2634                                                                                 }
2635                                                                                 
2636                                                                                 if (ps->do_occlude==0 || !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo)) {
2637                                                                                         
2638                                                                                         /* Only bother calculating the weights if we intersect */
2639                                                                                         if (ps->do_mask_normal || ps->dm_mtface_clone) {
2640 #if 1
2641                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2642                                                                                                 float uv_close[2];
2643                                                                                                 float fac= closest_to_line_v2(uv_close, uv, tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2]);
2644                                                                                                 if              (fac < 0.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx1]);
2645                                                                                                 else if (fac > 1.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx2]);
2646
2647                                                                                                 if (side) {
2648                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[2], tf_uv_pxoffset[3], uv_close, w);
2649                                                                                                 }
2650                                                                                                 else {
2651                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[1], tf_uv_pxoffset[2], uv_close, w);
2652                                                                                                 }
2653 #else                                                                                   /* this is buggy with quads, don't use for now */
2654
2655                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2656                                                                                                 fac = fac1 + (fac * (fac2-fac1));
2657
2658                                                                                                 w[0]=w[1]=w[2]= 0.0;
2659                                                                                                 if (side) {
2660                                                                                                         w[fidx1?fidx1-1:0] = 1.0f-fac;
2661                                                                                                         w[fidx2?fidx2-1:0] = fac;
2662                                                                                                 }
2663                                                                                                 else {
2664                                                                                                         w[fidx1] = 1.0f-fac;
2665                                                                                                         w[fidx2] = fac;
2666                                                                                                 }
2667 #endif
2668                                                                                         }
2669                                                                                         
2670                                                                                         /* a pity we need to get the worldspace pixel location here */
2671                                                                                         if (do_clip) {
2672                                                                                                 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);
2673                                                                                                 else            interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
2674
2675                                                                                                 if (ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2676                                                                                                         continue; /* Watch out that no code below this needs to run */
2677                                                                                                 }
2678                                                                                         }
2679                                                                                         
2680                                                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2681                                                                                         
2682                                                                                         if (mask > 0.0f) {
2683                                                                                                 BLI_linklist_prepend_arena(
2684                                                                                                         bucketPixelNodes,
2685                                                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index, image_index, pixelScreenCo, side, w),
2686                                                                                                         arena
2687                                                                                                 );
2688                                                                                         }
2689                                                                                         
2690                                                                                 }
2691                                                                         }
2692                                                                         else if (has_x_isect) {
2693                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2694                                                                                 break;
2695                                                                         }
2696                                                                 }
2697                                                                 
2698 #if 0                                                   /* TODO - investigate why this dosnt work sometimes! it should! */
2699                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2700                                                                 if (has_x_isect==0 && has_isect) { 
2701                                                                         break;
2702                                                                 }
2703 #endif
2704                                                         }
2705                                                 }
2706                                         }
2707                                 }
2708                         }
2709                 }
2710         }
2711 #endif // PROJ_DEBUG_NOSEAMBLEED
2712 }
2713
2714
2715 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2716 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2717 {
2718         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2719         /* 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 */
2720         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 */
2721         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2722         
2723         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2724         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2725         
2726         /* in case the rect is outside the mesh 2d bounds */
2727         CLAMP(bucketMin[0], 0, ps->buckets_x);
2728         CLAMP(bucketMin[1], 0, ps->buckets_y);
2729         
2730         CLAMP(bucketMax[0], 0, ps->buckets_x);
2731         CLAMP(bucketMax[1], 0, ps->buckets_y);
2732 }
2733
2734 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2735 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2736 {
2737         bucket_bounds->xmin =   ps->screenMin[0]+((bucket_x)*(ps->screen_width / ps->buckets_x));               /* left */
2738         bucket_bounds->xmax =   ps->screenMin[0]+((bucket_x+1)*(ps->screen_width / ps->buckets_x));     /* right */
2739         
2740         bucket_bounds->ymin =   ps->screenMin[1]+((bucket_y)*(ps->screen_height / ps->buckets_y));              /* bottom */
2741         bucket_bounds->ymax =   ps->screenMin[1]+((bucket_y+1)*(ps->screen_height  / ps->buckets_y));   /* top */
2742 }
2743
2744 /* Fill this bucket with pixels from the faces that intersect it.
2745  * 
2746  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2747 static void project_bucket_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, rctf *bucket_bounds)
2748 {
2749         LinkNode *node;
2750         int face_index, image_index=0;
2751         ImBuf *ibuf = NULL;
2752         Image *tpage_last = NULL, *tpage;
2753         Image *ima = NULL;
2754
2755         if (ps->image_tot==1) {
2756                 /* Simple loop, no context switching */
2757                 ibuf = ps->projImages[0].ibuf;
2758                 ima = ps->projImages[0].ima;
2759
2760                 for (node = ps->bucketFaces[bucket_index]; node; node= node->next) { 
2761                         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);
2762                 }
2763         }
2764         else {
2765                 
2766                 /* More complicated loop, switch between images */
2767                 for (node = ps->bucketFaces[bucket_index]; node; node= node->next) {
2768                         face_index = GET_INT_FROM_POINTER(node->link);
2769                                 
2770                         /* Image context switching */
2771                         tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
2772                         if (tpage_last != tpage) {
2773                                 tpage_last = tpage;
2774
2775                                 for (image_index=0; image_index < ps->image_tot; image_index++) {
2776                                         if (ps->projImages[image_index].ima == tpage_last) {
2777                                                 ibuf = ps->projImages[image_index].ibuf;
2778                                                 ima = ps->projImages[image_index].ima;
2779                                                 break;
2780                                         }
2781                                 }
2782                         }
2783                         /* context switching done */
2784                         
2785                         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);
2786                 }
2787         }
2788         
2789         ps->bucketFlags[bucket_index] |= PROJ_BUCKET_INIT;
2790 }
2791
2792
2793 /* We want to know if a bucket and a face overlap in screen-space
2794  * 
2795  * Note, if this ever returns false positives its not that bad, since a face in the bounding area will have its pixels
2796  * calculated when it might not be needed later, (at the moment at least)
2797  * obviously it shouldn't have bugs though */
2798
2799 static int project_bucket_face_isect(ProjPaintState *ps, int bucket_x, int bucket_y, const MFace *mf)
2800 {
2801         /* TODO - replace this with a tricker method that uses sideofline for all screenCoords's edges against the closest bucket corner */
2802         rctf bucket_bounds;
2803         float p1[2], p2[2], p3[2], p4[2];
2804         float *v, *v1,*v2,*v3,*v4=NULL;
2805         int fidx;
2806         
2807         project_bucket_bounds(ps, bucket_x, bucket_y, &bucket_bounds);
2808         
2809         /* Is one of the faces verts in the bucket bounds? */
2810         
2811         fidx = mf->v4 ? 3:2;
2812         do {
2813                 v = ps->screenCoords[ (*(&mf->v1 + fidx)) ];
2814                 if (BLI_in_rctf(&bucket_bounds, v[0], v[1])) {
2815                         return 1;
2816                 }
2817         } while (fidx--);
2818         
2819         v1 = ps->screenCoords[mf->v1];
2820         v2 = ps->screenCoords[mf->v2];
2821         v3 = ps->screenCoords[mf->v3];
2822         if (mf->v4) {
2823                 v4 = ps->screenCoords[mf->v4];
2824         }
2825         
2826         p1[0] = bucket_bounds.xmin; p1[1] = bucket_bounds.ymin;
2827         p2[0] = bucket_bounds.xmin;     p2[1] = bucket_bounds.ymax;
2828         p3[0] = bucket_bounds.xmax;     p3[1] = bucket_bounds.ymax;
2829         p4[0] = bucket_bounds.xmax;     p4[1] = bucket_bounds.ymin;
2830                 
2831         if (mf->v4) {
2832                 if ( isect_point_quad_v2(p1, v1, v2, v3, v4) ||
2833                      isect_point_quad_v2(p2, v1, v2, v3, v4) ||
2834                      isect_point_quad_v2(p3, v1, v2, v3, v4) ||
2835                      isect_point_quad_v2(p4, v1, v2, v3, v4) ||
2836
2837                         /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2838                         (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3) || isect_line_line_v2(p1, p2, v3, v4)) ||
2839                         (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3) || isect_line_line_v2(p2, p3, v3, v4)) ||
2840                         (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3) || isect_line_line_v2(p3, p4, v3, v4)) ||
2841                         (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3) || isect_line_line_v2(p4, p1, v3, v4))
2842                 ) {
2843                         return 1;
2844                 }
2845         }
2846         else {