Merging r47581 through r47603 from trunk into soc-2011-tomato
[blender.git] / source / blender / editors / sculpt_paint / paint_image.c
1 /*
2  * ***** BEGIN GPL LICENSE BLOCK *****
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * along with this program; if not, write to the Free Software Foundation,
15  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
16  *
17  * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
18  * All rights reserved.
19  *
20  * The Original Code is: some of this file.
21  *
22  * Contributor(s): Jens Ole Wund (bjornmose), Campbell Barton (ideasman42)
23  *
24  * ***** END GPL LICENSE BLOCK *****
25  */
26
27 /** \file blender/editors/sculpt_paint/paint_image.c
28  *  \ingroup edsculpt
29  *  \brief Functions to paint images in 2D and 3D.
30  */
31
32 #include <float.h>
33 #include <string.h>
34 #include <stdio.h>
35 #include <math.h>
36
37 #include "MEM_guardedalloc.h"
38
39 #ifdef WIN32
40 #  include "BLI_winstuff.h"
41 #endif
42
43 #include "BLI_math.h"
44 #include "BLI_blenlib.h"
45 #include "BLI_dynstr.h"
46 #include "BLI_linklist.h"
47 #include "BLI_memarena.h"
48 #include "BLI_threads.h"
49 #include "BLI_utildefines.h"
50
51 #include "PIL_time.h"
52
53 #include "IMB_imbuf.h"
54 #include "IMB_imbuf_types.h"
55
56 #include "DNA_brush_types.h"
57 #include "DNA_camera_types.h"
58 #include "DNA_mesh_types.h"
59 #include "DNA_meshdata_types.h"
60 #include "DNA_node_types.h"
61 #include "DNA_object_types.h"
62 #include "DNA_scene_types.h"
63 #include "DNA_texture_types.h"
64
65 #include "BKE_camera.h"
66 #include "BKE_context.h"
67 #include "BKE_depsgraph.h"
68 #include "BKE_DerivedMesh.h"
69 #include "BKE_idprop.h"
70 #include "BKE_brush.h"
71 #include "BKE_image.h"
72 #include "BKE_library.h"
73 #include "BKE_main.h"
74 #include "BKE_mesh.h"
75 #include "BKE_node.h"
76 #include "BKE_object.h"
77 #include "BKE_paint.h"
78 #include "BKE_report.h"
79 #include "BKE_scene.h"
80 #include "BKE_global.h"
81 #include "BKE_deform.h"
82
83 #include "BKE_tessmesh.h"
84
85 #include "BIF_gl.h"
86 #include "BIF_glutil.h"
87
88 #include "UI_view2d.h"
89
90 #include "ED_image.h"
91 #include "ED_screen.h"
92 #include "ED_sculpt.h"
93 #include "ED_uvedit.h"
94 #include "ED_view3d.h"
95 #include "ED_mesh.h"
96
97 #include "WM_api.h"
98 #include "WM_types.h"
99
100 #include "RNA_access.h"
101 #include "RNA_define.h"
102 #include "RNA_enum_types.h"
103
104 #include "GPU_draw.h"
105 #include "GPU_extensions.h"
106
107 #include "paint_intern.h"
108
109 /* Defines and Structs */
110
111 #define IMAPAINT_CHAR_TO_FLOAT(c) ((c) / 255.0f)
112
113 #define IMAPAINT_FLOAT_RGB_TO_CHAR(c, f)  {                                   \
114         (c)[0]= FTOCHAR((f)[0]);                                                  \
115         (c)[1]= FTOCHAR((f)[1]);                                                  \
116         (c)[2]= FTOCHAR((f)[2]);                                                  \
117 } (void)0
118 #define IMAPAINT_FLOAT_RGBA_TO_CHAR(c, f)  {                                  \
119         (c)[0]= FTOCHAR((f)[0]);                                                  \
120         (c)[1]= FTOCHAR((f)[1]);                                                  \
121         (c)[2]= FTOCHAR((f)[2]);                                                  \
122         (c)[3]= FTOCHAR((f)[3]);                                                  \
123 } (void)0
124 #define IMAPAINT_CHAR_RGB_TO_FLOAT(f, c)  {                                   \
125         (f)[0]= IMAPAINT_CHAR_TO_FLOAT((c)[0]);                                   \
126         (f)[1]= IMAPAINT_CHAR_TO_FLOAT((c)[1]);                                   \
127         (f)[2]= IMAPAINT_CHAR_TO_FLOAT((c)[2]);                                   \
128 } (void)0
129 #define IMAPAINT_CHAR_RGBA_TO_FLOAT(f, c)  {                                  \
130         (f)[0]= IMAPAINT_CHAR_TO_FLOAT((c)[0]);                                   \
131         (f)[1]= IMAPAINT_CHAR_TO_FLOAT((c)[1]);                                   \
132         (f)[2]= IMAPAINT_CHAR_TO_FLOAT((c)[2]);                                   \
133         (f)[3]= IMAPAINT_CHAR_TO_FLOAT((c)[3]);                                   \
134 } (void)0
135
136 #define IMAPAINT_FLOAT_RGB_COPY(a, b) copy_v3_v3(a, b)
137
138 #define IMAPAINT_TILE_BITS          6
139 #define IMAPAINT_TILE_SIZE          (1 << IMAPAINT_TILE_BITS)
140 #define IMAPAINT_TILE_NUMBER(size)  (((size) + IMAPAINT_TILE_SIZE - 1) >> IMAPAINT_TILE_BITS)
141
142 static void imapaint_image_update(SpaceImage *sima, Image *image, ImBuf *ibuf, short texpaint);
143
144
145 typedef struct ImagePaintState {
146         SpaceImage *sima;
147         View2D *v2d;
148         Scene *scene;
149         bScreen *screen;
150
151         Brush *brush;
152         short tool, blend;
153         Image *image;
154         ImBuf *canvas;
155         ImBuf *clonecanvas;
156         short clonefreefloat;
157         char *warnpackedfile;
158         char *warnmultifile;
159
160         /* viewport texture paint only, but _not_ project paint */
161         Object *ob;
162         int faceindex;
163         float uv[2];
164         int do_facesel;
165
166         DerivedMesh    *dm;
167         int             dm_totface;
168         int             dm_release;
169
170         MFace          *dm_mface;
171         MTFace         *dm_mtface;
172 } ImagePaintState;
173
174 typedef struct ImagePaintPartialRedraw {
175         int x1, y1, x2, y2;
176         int enabled;
177 } ImagePaintPartialRedraw;
178
179 typedef struct ImagePaintRegion {
180         int destx, desty;
181         int srcx, srcy;
182         int width, height;
183 } ImagePaintRegion;
184
185 /* ProjectionPaint defines */
186
187 /* approx the number of buckets to have under the brush,
188  * used with the brush size to set the ps->buckets_x and ps->buckets_y value.
189  * 
190  * When 3 - a brush should have ~9 buckets under it at once
191  * ...this helps for threading while painting as well as
192  * avoiding initializing pixels that wont touch the brush */
193 #define PROJ_BUCKET_BRUSH_DIV 4
194
195 #define PROJ_BUCKET_RECT_MIN 4
196 #define PROJ_BUCKET_RECT_MAX 256
197
198 #define PROJ_BOUNDBOX_DIV 8
199 #define PROJ_BOUNDBOX_SQUARED  (PROJ_BOUNDBOX_DIV * PROJ_BOUNDBOX_DIV)
200
201 //#define PROJ_DEBUG_PAINT 1
202 //#define PROJ_DEBUG_NOSEAMBLEED 1
203 //#define PROJ_DEBUG_PRINT_CLIP 1
204 #define PROJ_DEBUG_WINCLIP 1
205
206 /* projectFaceSeamFlags options */
207 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
208 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
209 #define PROJ_FACE_SEAM1 (1 << 0)  /* If this face has a seam on any of its edges */
210 #define PROJ_FACE_SEAM2 (1 << 1)
211 #define PROJ_FACE_SEAM3 (1 << 2)
212 #define PROJ_FACE_SEAM4 (1 << 3)
213
214 #define PROJ_FACE_NOSEAM1   (1 << 4)
215 #define PROJ_FACE_NOSEAM2   (1 << 5)
216 #define PROJ_FACE_NOSEAM3   (1 << 6)
217 #define PROJ_FACE_NOSEAM4   (1 << 7)
218
219 #define PROJ_SRC_VIEW       1
220 #define PROJ_SRC_IMAGE_CAM  2
221 #define PROJ_SRC_IMAGE_VIEW 3
222
223 #define PROJ_VIEW_DATA_ID "view_data"
224 #define PROJ_VIEW_DATA_SIZE (4 * 4 + 4 * 4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
225
226
227 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
228  * as this number approaches  1.0f the likelihood increases of float precision errors where
229  * it is occluded by an adjacent face */
230 #define PROJ_FACE_SCALE_SEAM    0.99f
231
232 #define PROJ_BUCKET_NULL        0
233 #define PROJ_BUCKET_INIT        (1 << 0)
234 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
235
236 /* used for testing doubles, if a point is on a line etc */
237 #define PROJ_GEOM_TOLERANCE 0.00075f
238
239 /* vert flags */
240 #define PROJ_VERT_CULL 1
241
242 #define PI_80_DEG ((M_PI_2 / 9) * 8)
243
244 /* This is mainly a convenience struct used so we can keep an array of images we use
245  * Thir imbufs, etc, in 1 array, When using threads this array is copied for each thread
246  * because 'partRedrawRect' and 'touch' values would not be thread safe */
247 typedef struct ProjPaintImage {
248         Image *ima;
249         ImBuf *ibuf;
250         ImagePaintPartialRedraw *partRedrawRect;
251         void **undoRect; /* only used to build undo tiles after painting */
252         int touch;
253 } ProjPaintImage;
254
255 /* Main projection painting struct passed to all projection painting functions */
256 typedef struct ProjPaintState {
257         View3D *v3d;
258         RegionView3D *rv3d;
259         ARegion *ar;
260         Scene *scene;
261         int source; /* PROJ_SRC_**** */
262
263         Brush *brush;
264         short tool, blend;
265         Object *ob;
266         /* end similarities with ImagePaintState */
267         
268         DerivedMesh    *dm;
269         int dm_totface;
270         int dm_totvert;
271         int dm_release;
272
273         MVert          *dm_mvert;
274         MFace          *dm_mface;
275         MTFace         *dm_mtface;
276         MTFace         *dm_mtface_clone;    /* other UV map, use for cloning between layers */
277         MTFace         *dm_mtface_stencil;
278         
279         /* projection painting only */
280         MemArena *arena_mt[BLENDER_MAX_THREADS]; /* for multithreading, the first item is sometimes used for non threaded cases too */
281         LinkNode **bucketRect;              /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
282         LinkNode **bucketFaces;             /* bucketRect aligned array linkList of faces overlapping each bucket */
283         unsigned char *bucketFlags;         /* store if the bucks have been initialized  */
284 #ifndef PROJ_DEBUG_NOSEAMBLEED
285         char *faceSeamFlags;                /* store info about faces, if they are initialized etc*/
286         float (*faceSeamUVs)[4][2];         /* expanded UVs for faces to use as seams */
287         LinkNode **vertFaces;               /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
288 #endif
289         char *vertFlags;                    /* store options per vert, now only store if the vert is pointing away from the view */
290         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 */
291         int buckets_y;
292         
293         ProjPaintImage *projImages;
294         
295         int image_tot;              /* size of projectImages array */
296         
297         float (*screenCoords)[4];   /* verts projected into floating point screen space */
298         
299         float screenMin[2];         /* 2D bounds for mesh verts on the screen's plane (screenspace) */
300         float screenMax[2]; 
301         float screen_width;         /* Calculated from screenMin & screenMax */
302         float screen_height;
303         int winx, winy;             /* from the carea or from the projection render */
304         
305         /* options for projection painting */
306         int do_layer_clone;
307         int do_layer_stencil;
308         int do_layer_stencil_inv;
309         
310         short do_occlude;               /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
311         short do_backfacecull;          /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
312         short do_mask_normal;           /* mask out pixels based on their normals */
313         short do_new_shading_nodes;     /* cache BKE_scene_use_new_shading_nodes value */
314         float normal_angle;             /* what angle to mask at*/
315         float normal_angle_inner;
316         float normal_angle_range;       /* difference between normal_angle and normal_angle_inner, for easy access */
317         
318         short is_ortho;
319         short is_airbrush;              /* only to avoid using (ps.brush->flag & BRUSH_AIRBRUSH) */
320         short is_texbrush;              /* only to avoid running  */
321 #ifndef PROJ_DEBUG_NOSEAMBLEED
322         float seam_bleed_px;
323 #endif
324         /* clone vars */
325         float cloneOffset[2];
326         
327         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
328         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
329         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
330         float clipsta, clipend;
331         
332         /* reproject vars */
333         Image *reproject_image;
334         ImBuf *reproject_ibuf;
335
336
337         /* threads */
338         int thread_tot;
339         int bucketMin[2];
340         int bucketMax[2];
341         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
342 } ProjPaintState;
343
344 typedef union pixelPointer {
345         float *f_pt;            /* float buffer */
346         unsigned int *uint_pt; /* 2 ways to access a char buffer */
347         unsigned char *ch_pt;
348 } PixelPointer;
349
350 typedef union pixelStore {
351         unsigned char ch[4];
352         unsigned int uint;
353         float f[4];
354 } PixelStore;
355
356 typedef struct ProjPixel {
357         float projCoSS[2]; /* the floating point screen projection of this pixel */
358         
359         /* Only used when the airbrush is disabled.
360          * Store the max mask value to avoid painting over an area with a lower opacity
361          * with an advantage that we can avoid touching the pixel at all, if the 
362          * new mask value is lower then mask_max */
363         unsigned short mask_max;
364         
365         /* for various reasons we may want to mask out painting onto this pixel */
366         unsigned short mask;
367         
368         short x_px, y_px;
369         
370         PixelStore origColor;
371         PixelStore newColor;
372         PixelPointer pixel;
373         
374         short image_index; /* if anyone wants to paint onto more then 32768 images they can bite me */
375         unsigned char bb_cell_index;
376 } ProjPixel;
377
378 typedef struct ProjPixelClone {
379         struct ProjPixel __pp;
380         PixelStore clonepx;
381 } ProjPixelClone;
382
383 /* Finish projection painting structs */
384
385 typedef struct UndoImageTile {
386         struct UndoImageTile *next, *prev;
387
388         char idname[MAX_ID_NAME];  /* name instead of pointer*/
389         char ibufname[IB_FILENAME_SIZE];
390
391         void *rect;
392         int x, y;
393
394         short source, use_float;
395         char gen_type;
396 } UndoImageTile;
397
398 static ImagePaintPartialRedraw imapaintpartial = {0, 0, 0, 0, 0};
399
400 /* UNDO */
401
402 static void undo_copy_tile(UndoImageTile *tile, ImBuf *tmpibuf, ImBuf *ibuf, int restore)
403 {
404         /* copy or swap contents of tile->rect and region in ibuf->rect */
405         IMB_rectcpy(tmpibuf, ibuf, 0, 0, tile->x * IMAPAINT_TILE_SIZE,
406                     tile->y * IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE);
407
408         if (ibuf->rect_float) {
409                 SWAP(void *, tmpibuf->rect_float, tile->rect);
410         }
411         else {
412                 SWAP(void *, tmpibuf->rect, tile->rect);
413         }
414         
415         if (restore)
416                 IMB_rectcpy(ibuf, tmpibuf, tile->x * IMAPAINT_TILE_SIZE,
417                             tile->y * IMAPAINT_TILE_SIZE, 0, 0, IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE);
418 }
419
420 static void *image_undo_push_tile(Image *ima, ImBuf *ibuf, ImBuf **tmpibuf, int x_tile, int y_tile)
421 {
422         ListBase *lb = undo_paint_push_get_list(UNDO_PAINT_IMAGE);
423         UndoImageTile *tile;
424         int allocsize;
425         short use_float = ibuf->rect_float ? 1 : 0;
426
427         for (tile = lb->first; tile; tile = tile->next)
428                 if (tile->x == x_tile && tile->y == y_tile && ima->gen_type == tile->gen_type && ima->source == tile->source)
429                         if (tile->use_float == use_float)
430                                 if (strcmp(tile->idname, ima->id.name) == 0 && strcmp(tile->ibufname, ibuf->name) == 0)
431                                         return tile->rect;
432         
433         if (*tmpibuf == NULL)
434                 *tmpibuf = IMB_allocImBuf(IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, 32, IB_rectfloat | IB_rect);
435         
436         tile = MEM_callocN(sizeof(UndoImageTile), "UndoImageTile");
437         BLI_strncpy(tile->idname, ima->id.name, sizeof(tile->idname));
438         tile->x = x_tile;
439         tile->y = y_tile;
440
441         allocsize = IMAPAINT_TILE_SIZE * IMAPAINT_TILE_SIZE * 4;
442         allocsize *= (ibuf->rect_float) ? sizeof(float) : sizeof(char);
443         tile->rect = MEM_mapallocN(allocsize, "UndeImageTile.rect");
444
445         BLI_strncpy(tile->ibufname, ibuf->name, sizeof(tile->ibufname));
446
447         tile->gen_type = ima->gen_type;
448         tile->source = ima->source;
449         tile->use_float = use_float;
450
451         undo_copy_tile(tile, *tmpibuf, ibuf, 0);
452         undo_paint_push_count_alloc(UNDO_PAINT_IMAGE, allocsize);
453
454         BLI_addtail(lb, tile);
455         
456         return tile->rect;
457 }
458
459 static void image_undo_restore(bContext *C, ListBase *lb)
460 {
461         Main *bmain = CTX_data_main(C);
462         Image *ima = NULL;
463         ImBuf *ibuf, *tmpibuf;
464         UndoImageTile *tile;
465
466         tmpibuf = IMB_allocImBuf(IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, 32,
467                                  IB_rectfloat | IB_rect);
468         
469         for (tile = lb->first; tile; tile = tile->next) {
470                 short use_float;
471
472                 /* find image based on name, pointer becomes invalid with global undo */
473                 if (ima && strcmp(tile->idname, ima->id.name) == 0) {
474                         /* ima is valid */
475                 }
476                 else {
477                         ima = BLI_findstring(&bmain->image, tile->idname, offsetof(ID, name));
478                 }
479
480                 ibuf = BKE_image_get_ibuf(ima, NULL);
481
482                 if (ima && ibuf && strcmp(tile->ibufname, ibuf->name) != 0) {
483                         /* current ImBuf filename was changed, probably current frame
484                          * was changed when paiting on image sequence, rather than storing
485                          * full image user (which isn't so obvious, btw) try to find ImBuf with
486                          * matched file name in list of already loaded images */
487
488                         ibuf = BLI_findstring(&ima->ibufs, tile->ibufname, offsetof(ImBuf, name));
489                 }
490
491                 if (!ima || !ibuf || !(ibuf->rect || ibuf->rect_float))
492                         continue;
493
494                 if (ima->gen_type != tile->gen_type || ima->source != tile->source)
495                         continue;
496
497                 use_float = ibuf->rect_float ? 1 : 0;
498
499                 if (use_float != tile->use_float)
500                         continue;
501
502                 undo_copy_tile(tile, tmpibuf, ibuf, 1);
503
504                 GPU_free_image(ima); /* force OpenGL reload */
505                 if (ibuf->rect_float)
506                         ibuf->userflags |= IB_RECT_INVALID; /* force recreate of char rect */
507                 if (ibuf->mipmap[0])
508                         ibuf->userflags |= IB_MIPMAP_INVALID;  /* force mipmap recreatiom */
509
510         }
511
512         IMB_freeImBuf(tmpibuf);
513 }
514
515 static void image_undo_free(ListBase *lb)
516 {
517         UndoImageTile *tile;
518
519         for (tile = lb->first; tile; tile = tile->next)
520                 MEM_freeN(tile->rect);
521 }
522
523 /* get active image for face depending on old/new shading system */
524
525 static Image *imapaint_face_image(const ImagePaintState *s, int face_index)
526 {
527         Image *ima;
528
529         if (BKE_scene_use_new_shading_nodes(s->scene)) {
530                 MFace *mf = &s->dm_mface[face_index];
531                 ED_object_get_active_image(s->ob, mf->mat_nr + 1, &ima, NULL, NULL);
532         }
533         else {
534                 MTFace *tf = &s->dm_mtface[face_index];
535                 ima = tf->tpage;
536         }
537
538         return ima;
539 }
540
541 static Image *project_paint_face_image(const ProjPaintState *ps, MTFace *dm_mtface, int face_index)
542 {
543         Image *ima;
544
545         if (ps->do_new_shading_nodes) { /* cached BKE_scene_use_new_shading_nodes result */
546                 MFace *mf = ps->dm_mface + face_index;
547                 ED_object_get_active_image(ps->ob, mf->mat_nr + 1, &ima, NULL, NULL);
548         }
549         else {
550                 ima = dm_mtface[face_index].tpage;
551         }
552
553         return ima;
554 }
555
556 /* fast projection bucket array lookup, use the safe version for bound checking  */
557 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
558 {
559         /* If we were not dealing with screenspace 2D coords we could simple do...
560          * ps->bucketRect[x + (y*ps->buckets_y)] */
561         
562         /* please explain?
563          * projCoSS[0] - ps->screenMin[0]       : zero origin
564          * ... / ps->screen_width                               : range from 0.0 to 1.0
565          * ... * ps->buckets_x          : use as a bucket index
566          *
567          * Second multiplication does similar but for vertical offset
568          */
569         return (   (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
570                (   (   (int)(((projCoSS[1] - ps->screenMin[1])  / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
571 }
572
573 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
574 {
575         int bucket_index = project_bucket_offset(ps, projCoSS);
576         
577         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
578                 return -1;
579         }
580         else {
581                 return bucket_index;
582         }
583 }
584
585 /* still use 2D X,Y space but this works for verts transformed by a perspective matrix, using their 4th component as a weight */
586 static void barycentric_weights_v2_persp(float v1[4], float v2[4], float v3[4], float co[2], float w[3])
587 {
588         float wtot_inv, wtot;
589
590         w[0] = area_tri_signed_v2(v2, v3, co) / v1[3];
591         w[1] = area_tri_signed_v2(v3, v1, co) / v2[3];
592         w[2] = area_tri_signed_v2(v1, v2, co) / v3[3];
593         wtot = w[0] + w[1] + w[2];
594
595         if (wtot != 0.0f) {
596                 wtot_inv = 1.0f / wtot;
597
598                 w[0] = w[0] * wtot_inv;
599                 w[1] = w[1] * wtot_inv;
600                 w[2] = w[2] * wtot_inv;
601         }
602         else /* dummy values for zero area face */
603                 w[0] = w[1] = w[2] = 1.0f / 3.0f;
604 }
605
606 static float VecZDepthOrtho(float pt[2], float v1[3], float v2[3], float v3[3], float w[3])
607 {
608         barycentric_weights_v2(v1, v2, v3, pt, w);
609         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
610 }
611
612 static float VecZDepthPersp(float pt[2], float v1[4], float v2[4], float v3[4], float w[3])
613 {
614         float wtot_inv, wtot;
615         float w_tmp[3];
616
617         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
618         /* for the depth we need the weights to match what
619          * barycentric_weights_v2 would return, in this case its easiest just to
620          * undo the 4th axis division and make it unit-sum
621          *
622          * don't call barycentric_weights_v2() becaue our callers expect 'w'
623          * to be weighted from the perspective */
624         w_tmp[0] = w[0] * v1[3];
625         w_tmp[1] = w[1] * v2[3];
626         w_tmp[2] = w[2] * v3[3];
627
628         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
629
630         if (wtot != 0.0f) {
631                 wtot_inv = 1.0f / wtot;
632
633                 w_tmp[0] = w_tmp[0] * wtot_inv;
634                 w_tmp[1] = w_tmp[1] * wtot_inv;
635                 w_tmp[2] = w_tmp[2] * wtot_inv;
636         }
637         else /* dummy values for zero area face */
638                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
639         /* done mimicing barycentric_weights_v2() */
640
641         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
642 }
643
644
645 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
646 static int project_paint_PickFace(const ProjPaintState *ps, float pt[2], float w[3], int *side)
647 {
648         LinkNode *node;
649         float w_tmp[3];
650         float *v1, *v2, *v3, *v4;
651         int bucket_index;
652         int face_index;
653         int best_side = -1;
654         int best_face_index = -1;
655         float z_depth_best = FLT_MAX, z_depth;
656         MFace *mf;
657         
658         bucket_index = project_bucket_offset_safe(ps, pt);
659         if (bucket_index == -1)
660                 return -1;
661         
662         
663         
664         /* we could return 0 for 1 face buckets, as long as this function assumes
665          * that the point its testing is only every originated from an existing face */
666         
667         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
668                 face_index = GET_INT_FROM_POINTER(node->link);
669                 mf = ps->dm_mface + face_index;
670                 
671                 v1 = ps->screenCoords[mf->v1];
672                 v2 = ps->screenCoords[mf->v2];
673                 v3 = ps->screenCoords[mf->v3];
674                 
675                 if (isect_point_tri_v2(pt, v1, v2, v3)) {
676                         if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v2, v3, w_tmp);
677                         else z_depth = VecZDepthPersp(pt, v1, v2, v3, w_tmp);
678                         
679                         if (z_depth < z_depth_best) {
680                                 best_face_index = face_index;
681                                 best_side = 0;
682                                 z_depth_best = z_depth;
683                                 copy_v3_v3(w, w_tmp);
684                         }
685                 }
686                 else if (mf->v4) {
687                         v4 = ps->screenCoords[mf->v4];
688                         
689                         if (isect_point_tri_v2(pt, v1, v3, v4)) {
690                                 if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v3, v4, w_tmp);
691                                 else z_depth = VecZDepthPersp(pt, v1, v3, v4, w_tmp);
692
693                                 if (z_depth < z_depth_best) {
694                                         best_face_index = face_index;
695                                         best_side = 1;
696                                         z_depth_best = z_depth;
697                                         copy_v3_v3(w, w_tmp);
698                                 }
699                         }
700                 }
701         }
702         
703         *side = best_side;
704         return best_face_index; /* will be -1 or a valid face */
705 }
706
707 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
708 static void uvco_to_wrapped_pxco(float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
709 {
710         /* use */
711         *x = (float)fmodf(uv[0], 1.0f);
712         *y = (float)fmodf(uv[1], 1.0f);
713         
714         if (*x < 0.0f) *x += 1.0f;
715         if (*y < 0.0f) *y += 1.0f;
716         
717         *x = *x * ibuf_x - 0.5f;
718         *y = *y * ibuf_y - 0.5f;
719 }
720
721 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
722 static int project_paint_PickColor(const ProjPaintState *ps, float pt[2], float *rgba_fp, unsigned char *rgba, const int interp)
723 {
724         float w[3], uv[2];
725         int side;
726         int face_index;
727         MTFace *tf;
728         Image *ima;
729         ImBuf *ibuf;
730         int xi, yi;
731         
732         
733         face_index = project_paint_PickFace(ps, pt, w, &side);
734         
735         if (face_index == -1)
736                 return 0;
737         
738         tf = ps->dm_mtface + face_index;
739         
740         if (side == 0) {
741                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[1], tf->uv[2], w);
742         }
743         else { /* QUAD */
744                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[2], tf->uv[3], w);
745         }
746
747         ima = project_paint_face_image(ps, ps->dm_mtface, face_index);
748         ibuf = ima->ibufs.first; /* we must have got the imbuf before getting here */
749         if (!ibuf) return 0;
750         
751         if (interp) {
752                 float x, y;
753                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
754                 
755                 if (ibuf->rect_float) {
756                         if (rgba_fp) {
757                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
758                         }
759                         else {
760                                 float rgba_tmp_f[4];
761                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
762                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(rgba, rgba_tmp_f);
763                         }
764                 }
765                 else {
766                         if (rgba) {
767                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
768                         }
769                         else {
770                                 unsigned char rgba_tmp[4];
771                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
772                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(rgba_fp, rgba_tmp);
773                         }
774                 }
775         }
776         else {
777                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
778                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
779                 //if (xi<0 || xi>=ibuf->x  ||  yi<0 || yi>=ibuf->y) return 0;
780                 
781                 /* wrap */
782                 xi = ((int)(uv[0] * ibuf->x)) % ibuf->x;
783                 if (xi < 0) xi += ibuf->x;
784                 yi = ((int)(uv[1] * ibuf->y)) % ibuf->y;
785                 if (yi < 0) yi += ibuf->y;
786                 
787                 
788                 if (rgba) {
789                         if (ibuf->rect_float) {
790                                 float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
791                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(rgba, rgba_tmp_fp);
792                         }
793                         else {
794                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
795                         }
796                 }
797                 
798                 if (rgba_fp) {
799                         if (ibuf->rect_float) {
800                                 copy_v4_v4(rgba_fp, ((float *)ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
801                         }
802                         else {
803                                 char *tmp_ch = ((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
804                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(rgba_fp, tmp_ch);
805                         }
806                 }
807         }
808         return 1;
809 }
810
811 /* Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusuion test)
812  * return...
813  *  0   : no occlusion
814  * -1   : no occlusion but 2D intersection is true (avoid testing the other half of a quad)
815  *  1   : occluded
816  *  2   : occluded with w[3] weights set (need to know in some cases) */
817
818 static int project_paint_occlude_ptv(float pt[3], float v1[4], float v2[4], float v3[4], float w[3], int is_ortho)
819 {
820         /* if all are behind us, return false */
821         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
822                 return 0;
823                 
824         /* do a 2D point in try intersection */
825         if (!isect_point_tri_v2(pt, v1, v2, v3))
826                 return 0;  /* we know there is  */
827         
828
829         /* From here on we know there IS an intersection */
830         /* if ALL of the verts are infront of us then we know it intersects ? */
831         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
832                 return 1;
833         }
834         else {
835                 /* we intersect? - find the exact depth at the point of intersection */
836                 /* Is this point is occluded by another face? */
837                 if (is_ortho) {
838                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
839                 }
840                 else {
841                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
842                 }
843         }
844         return -1;
845 }
846
847
848 static int project_paint_occlude_ptv_clip(const ProjPaintState *ps, const MFace *mf,
849                                           float pt[3], float v1[4], float v2[4], float v3[4],
850                                           const int side)
851 {
852         float w[3], wco[3];
853         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, ps->is_ortho);
854
855         if (ret <= 0)
856                 return ret;
857
858         if (ret == 1) { /* weights not calculated */
859                 if (ps->is_ortho) barycentric_weights_v2(v1, v2, v3, pt, w);
860                 else barycentric_weights_v2_persp(v1, v2, v3, pt, w);
861         }
862
863         /* Test if we're in the clipped area, */
864         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);
865         else interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
866         
867         if (!ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
868                 return 1;
869         }
870         
871         return -1;
872 }
873
874
875 /* Check if a screenspace location is occluded by any other faces
876  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
877  * and dosn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
878 static int project_bucket_point_occluded(const ProjPaintState *ps, LinkNode *bucketFace, const int orig_face, float pixelScreenCo[4])
879 {
880         MFace *mf;
881         int face_index;
882         int isect_ret;
883         float w[3]; /* not needed when clipping */
884         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
885         
886         /* we could return 0 for 1 face buckets, as long as this function assumes
887          * that the point its testing is only every originated from an existing face */
888
889         for (; bucketFace; bucketFace = bucketFace->next) {
890                 face_index = GET_INT_FROM_POINTER(bucketFace->link);
891
892                 if (orig_face != face_index) {
893                         mf = ps->dm_mface + face_index;
894                         if (do_clip)
895                                 isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], 0);
896                         else
897                                 isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], w, ps->is_ortho);
898
899                         /* Note, if isect_ret==-1 then we don't want to test the other side of the quad */
900                         if (isect_ret == 0 && mf->v4) {
901                                 if (do_clip)
902                                         isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], 1);
903                                 else
904                                         isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], w, ps->is_ortho);
905                         }
906                         if (isect_ret >= 1) {
907                                 /* TODO - we may want to cache the first hit,
908                                  * it is not possible to swap the face order in the list anymore */
909                                 return 1;
910                         }
911                 }
912         }
913         return 0;
914 }
915
916 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
917  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
918 #define ISECT_TRUE 1
919 #define ISECT_TRUE_P1 2
920 #define ISECT_TRUE_P2 3
921 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
922 {
923         float y_diff;
924         
925         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
926                 *x_isect = p1[0];
927                 return ISECT_TRUE_P1;
928         }
929         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
930                 *x_isect = p2[0];
931                 return ISECT_TRUE_P2;
932         }
933         
934         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
935         
936         if (y_diff < 0.000001f) {
937                 *x_isect = (p1[0] + p2[0]) * 0.5f;
938                 return ISECT_TRUE;              
939         }
940         
941         if (p1[1] > y_level && p2[1] < y_level) {
942                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /*(p1[1]-p2[1]);*/
943                 return ISECT_TRUE;
944         }
945         else if (p1[1] < y_level && p2[1] > y_level) {
946                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /*(p2[1]-p1[1]);*/
947                 return ISECT_TRUE;
948         }
949         else {
950                 return 0;
951         }
952 }
953
954 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
955 {
956         float x_diff;
957         
958         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
959                 *y_isect = p1[1];
960                 return ISECT_TRUE_P1;
961         }
962         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
963                 *y_isect = p2[1];
964                 return ISECT_TRUE_P2;
965         }
966         
967         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
968         
969         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
970                 *y_isect = (p1[0] + p2[0]) * 0.5f;
971                 return ISECT_TRUE;              
972         }
973         
974         if (p1[0] > x_level && p2[0] < x_level) {
975                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff; /*(p1[0]-p2[0]);*/
976                 return ISECT_TRUE;
977         }
978         else if (p1[0] < x_level && p2[0] > x_level) {
979                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff; /*(p2[0]-p1[0]);*/
980                 return ISECT_TRUE;
981         }
982         else {
983                 return 0;
984         }
985 }
986
987 /* simple func use for comparing UV locations to check if there are seams.
988  * Its possible this gives incorrect results, when the UVs for 1 face go into the next 
989  * tile, but do not do this for the adjacent face, it could return a false positive.
990  * This is so unlikely that Id not worry about it. */
991 #ifndef PROJ_DEBUG_NOSEAMBLEED
992 static int cmp_uv(const float vec2a[2], const float vec2b[2])
993 {
994         /* if the UV's are not between 0.0 and 1.0 */
995         float xa = (float)fmodf(vec2a[0], 1.0f);
996         float ya = (float)fmodf(vec2a[1], 1.0f);
997         
998         float xb = (float)fmodf(vec2b[0], 1.0f);
999         float yb = (float)fmodf(vec2b[1], 1.0f);        
1000         
1001         if (xa < 0.0f) xa += 1.0f;
1002         if (ya < 0.0f) ya += 1.0f;
1003         
1004         if (xb < 0.0f) xb += 1.0f;
1005         if (yb < 0.0f) yb += 1.0f;
1006         
1007         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
1008 }
1009 #endif
1010
1011 /* set min_px and max_px to the image space bounds of the UV coords 
1012  * return zero if there is no area in the returned rectangle */
1013 #ifndef PROJ_DEBUG_NOSEAMBLEED
1014 static int pixel_bounds_uv(
1015         const float uv1[2], const float uv2[2], const float uv3[2], const float uv4[2],
1016         rcti *bounds_px,
1017         const int ibuf_x, const int ibuf_y,
1018         int is_quad
1019         )
1020 {
1021         float min_uv[2], max_uv[2]; /* UV bounds */
1022         
1023         INIT_MINMAX2(min_uv, max_uv);
1024         
1025         DO_MINMAX2(uv1, min_uv, max_uv);
1026         DO_MINMAX2(uv2, min_uv, max_uv);
1027         DO_MINMAX2(uv3, min_uv, max_uv);
1028         if (is_quad)
1029                 DO_MINMAX2(uv4, min_uv, max_uv);
1030         
1031         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
1032         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
1033         
1034         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
1035         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
1036         
1037         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
1038         
1039         /* face uses no UV area when quantized to pixels? */
1040         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
1041 }
1042 #endif
1043
1044 static int pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
1045 {
1046         float min_uv[2], max_uv[2]; /* UV bounds */
1047         
1048         if (tot == 0) {
1049                 return 0;
1050         }
1051         
1052         INIT_MINMAX2(min_uv, max_uv);
1053         
1054         while (tot--) {
1055                 DO_MINMAX2((*uv), min_uv, max_uv);
1056                 uv++;
1057         }
1058         
1059         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
1060         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
1061         
1062         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
1063         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
1064         
1065         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
1066         
1067         /* face uses no UV area when quantized to pixels? */
1068         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
1069 }
1070
1071 #ifndef PROJ_DEBUG_NOSEAMBLEED
1072
1073 /* This function returns 1 if this face has a seam along the 2 face-vert indices
1074  * 'orig_i1_fidx' and 'orig_i2_fidx' */
1075 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)
1076 {
1077         LinkNode *node;
1078         int face_index;
1079         unsigned int i1, i2;
1080         int i1_fidx = -1, i2_fidx = -1; /* index in face */
1081         MFace *mf;
1082         MTFace *tf;
1083         const MFace *orig_mf = ps->dm_mface + orig_face;  
1084         const MTFace *orig_tf = ps->dm_mtface + orig_face;
1085         
1086         /* vert indices from face vert order indices */
1087         i1 = (*(&orig_mf->v1 + orig_i1_fidx));
1088         i2 = (*(&orig_mf->v1 + orig_i2_fidx));
1089         
1090         for (node = ps->vertFaces[i1]; node; node = node->next) {
1091                 face_index = GET_INT_FROM_POINTER(node->link);
1092
1093                 if (face_index != orig_face) {
1094                         mf = ps->dm_mface + face_index;
1095                         /* could check if the 2 faces images match here,
1096                          * but then there wouldn't be a way to return the opposite face's info */
1097                         
1098                         
1099                         /* We need to know the order of the verts in the adjacent face 
1100                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
1101                         if      (mf->v1 == i1) i1_fidx = 0;
1102                         else if (mf->v2 == i1) i1_fidx = 1;
1103                         else if (mf->v3 == i1) i1_fidx = 2;
1104                         else if (mf->v4 && mf->v4 == i1) i1_fidx = 3;
1105
1106                         if      (mf->v1 == i2) i2_fidx = 0;
1107                         else if (mf->v2 == i2) i2_fidx = 1;
1108                         else if (mf->v3 == i2) i2_fidx = 2;
1109                         else if (mf->v4 && mf->v4 == i2) i2_fidx = 3;
1110                         
1111                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
1112                         if (i2_fidx != -1) {
1113                                 Image *tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
1114                                 Image *orig_tpage = project_paint_face_image(ps, ps->dm_mtface, orig_face);
1115
1116                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
1117                                 tf = ps->dm_mtface + face_index;
1118                                 
1119                                 /* set up the other face */
1120                                 *other_face = face_index;
1121                                 *orig_fidx = (i1_fidx < i2_fidx) ? i1_fidx : i2_fidx;
1122                                 
1123                                 /* first test if they have the same image */
1124                                 if ((orig_tpage == tpage) &&
1125                                     cmp_uv(orig_tf->uv[orig_i1_fidx], tf->uv[i1_fidx]) &&
1126                                     cmp_uv(orig_tf->uv[orig_i2_fidx], tf->uv[i2_fidx]) )
1127                                 {
1128                                         // printf("SEAM (NONE)\n");
1129                                         return 0;
1130                                         
1131                                 }
1132                                 else {
1133                                         // printf("SEAM (UV GAP)\n");
1134                                         return 1;
1135                                 }
1136                         }
1137                 }
1138         }
1139         // printf("SEAM (NO FACE)\n");
1140         *other_face = -1;
1141         return 1;
1142 }
1143
1144 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
1145  * since the outset coords are a margin that keep an even distance from the original UV's,
1146  * note that the image aspect is taken into account */
1147 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)
1148 {
1149         float a1, a2, a3, a4 = 0.0f;
1150         float puv[4][2]; /* pixelspace uv's */
1151         float no1[2], no2[2], no3[2], no4[2]; /* normals */
1152         float dir1[2], dir2[2], dir3[2], dir4[2];
1153         float ibuf_inv[2];
1154
1155         ibuf_inv[0] = 1.0f / (float)ibuf_x;
1156         ibuf_inv[1] = 1.0f / (float)ibuf_y;
1157
1158         /* make UV's in pixel space so we can */
1159         puv[0][0] = orig_uv[0][0] * ibuf_x;
1160         puv[0][1] = orig_uv[0][1] * ibuf_y;
1161         
1162         puv[1][0] = orig_uv[1][0] * ibuf_x;
1163         puv[1][1] = orig_uv[1][1] * ibuf_y;
1164         
1165         puv[2][0] = orig_uv[2][0] * ibuf_x;
1166         puv[2][1] = orig_uv[2][1] * ibuf_y;
1167         
1168         if (is_quad) {
1169                 puv[3][0] = orig_uv[3][0] * ibuf_x;
1170                 puv[3][1] = orig_uv[3][1] * ibuf_y;
1171         }
1172         
1173         /* face edge directions */
1174         sub_v2_v2v2(dir1, puv[1], puv[0]);
1175         sub_v2_v2v2(dir2, puv[2], puv[1]);
1176         normalize_v2(dir1);
1177         normalize_v2(dir2);
1178         
1179         if (is_quad) {
1180                 sub_v2_v2v2(dir3, puv[3], puv[2]);
1181                 sub_v2_v2v2(dir4, puv[0], puv[3]);
1182                 normalize_v2(dir3);
1183                 normalize_v2(dir4);
1184         }
1185         else {
1186                 sub_v2_v2v2(dir3, puv[0], puv[2]);
1187                 normalize_v2(dir3);
1188         }
1189
1190         /* TODO - angle_normalized_v2v2(...) * (M_PI/180.0f)
1191          * This is incorrect. Its already given radians but without it wont work.
1192          * need to look into a fix - campbell */
1193         if (is_quad) {
1194                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir4, dir1) * ((float)M_PI / 180.0f));
1195                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI / 180.0f));
1196                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI / 180.0f));
1197                 a4 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir4) * ((float)M_PI / 180.0f));
1198         }
1199         else {
1200                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir1) * ((float)M_PI / 180.0f));
1201                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI / 180.0f));
1202                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI / 180.0f));
1203         }
1204         
1205         if (is_quad) {
1206                 sub_v2_v2v2(no1, dir4, dir1);
1207                 sub_v2_v2v2(no2, dir1, dir2);
1208                 sub_v2_v2v2(no3, dir2, dir3);
1209                 sub_v2_v2v2(no4, dir3, dir4);
1210                 normalize_v2(no1);
1211                 normalize_v2(no2);
1212                 normalize_v2(no3);
1213                 normalize_v2(no4);
1214                 mul_v2_fl(no1, a1 * scaler);
1215                 mul_v2_fl(no2, a2 * scaler);
1216                 mul_v2_fl(no3, a3 * scaler);
1217                 mul_v2_fl(no4, a4 * scaler);
1218                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1219                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1220                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1221                 add_v2_v2v2(outset_uv[3], puv[3], no4);
1222                 mul_v2_v2(outset_uv[0], ibuf_inv);
1223                 mul_v2_v2(outset_uv[1], ibuf_inv);
1224                 mul_v2_v2(outset_uv[2], ibuf_inv);
1225                 mul_v2_v2(outset_uv[3], ibuf_inv);
1226         }
1227         else {
1228                 sub_v2_v2v2(no1, dir3, dir1);
1229                 sub_v2_v2v2(no2, dir1, dir2);
1230                 sub_v2_v2v2(no3, dir2, dir3);
1231                 normalize_v2(no1);
1232                 normalize_v2(no2);
1233                 normalize_v2(no3);
1234                 mul_v2_fl(no1, a1 * scaler);
1235                 mul_v2_fl(no2, a2 * scaler);
1236                 mul_v2_fl(no3, a3 * scaler);
1237                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1238                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1239                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1240
1241                 mul_v2_v2(outset_uv[0], ibuf_inv);
1242                 mul_v2_v2(outset_uv[1], ibuf_inv);
1243                 mul_v2_v2(outset_uv[2], ibuf_inv);
1244         }
1245 }
1246
1247 /* 
1248  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1249  * 1<<i - where i is (0-3) 
1250  * 
1251  * If we're multithreadng, make sure threads are locked when this is called
1252  */
1253 static void project_face_seams_init(const ProjPaintState *ps, const int face_index, const int is_quad)
1254 {
1255         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1256         int fidx1 = is_quad ? 3 : 2;
1257         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 */
1258         
1259         do {
1260                 if ((ps->faceSeamFlags[face_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1261                         if (check_seam(ps, face_index, fidx1, fidx2, &other_face, &other_fidx)) {
1262                                 ps->faceSeamFlags[face_index] |= 1 << fidx1;
1263                                 if (other_face != -1)
1264                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1265                         }
1266                         else {
1267                                 ps->faceSeamFlags[face_index] |= 16 << fidx1;
1268                                 if (other_face != -1)
1269                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1270                         }
1271                 }
1272                 
1273                 fidx2 = fidx1;
1274         } while (fidx1--);
1275 }
1276 #endif // PROJ_DEBUG_NOSEAMBLEED
1277
1278
1279 /* Converts a UV location to a 3D screenspace location
1280  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1281  * 
1282  * This is used for finding a pixels location in screenspace for painting */
1283 static void screen_px_from_ortho(
1284         float uv[2],
1285         float v1co[3], float v2co[3], float v3co[3],  /* Screenspace coords */
1286         float uv1co[2], float uv2co[2], float uv3co[2],
1287         float pixelScreenCo[4],
1288         float w[3])
1289 {
1290         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1291         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1292 }
1293
1294 /* same as screen_px_from_ortho except we need to take into account
1295  * the perspective W coord for each vert */
1296 static void screen_px_from_persp(
1297         float uv[2],
1298         float v1co[4], float v2co[4], float v3co[4],  /* screenspace coords */
1299         float uv1co[2], float uv2co[2], float uv3co[2],
1300         float pixelScreenCo[4],
1301         float w[3])
1302 {
1303
1304         float wtot_inv, wtot;
1305         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1306         
1307         /* re-weight from the 4th coord of each screen vert */
1308         w[0] *= v1co[3];
1309         w[1] *= v2co[3];
1310         w[2] *= v3co[3];
1311         
1312         wtot = w[0] + w[1] + w[2];
1313         
1314         if (wtot > 0.0f) {
1315                 wtot_inv = 1.0f / wtot;
1316                 w[0] *= wtot_inv;
1317                 w[1] *= wtot_inv;
1318                 w[2] *= wtot_inv;
1319         }
1320         else {
1321                 w[0] = w[1] = w[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1322         }
1323         /* done re-weighting */
1324         
1325         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1326 }
1327
1328 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])
1329 {
1330         float *uvCo1, *uvCo2, *uvCo3;
1331         float uv_other[2], x, y;
1332         
1333         uvCo1 =  (float *)tf_other->uv[0];
1334         if (side == 1) {
1335                 uvCo2 =  (float *)tf_other->uv[2];
1336                 uvCo3 =  (float *)tf_other->uv[3];
1337         }
1338         else {
1339                 uvCo2 =  (float *)tf_other->uv[1];
1340                 uvCo3 =  (float *)tf_other->uv[2];
1341         }
1342         
1343         interp_v2_v2v2v2(uv_other, uvCo1, uvCo2, uvCo3, (float *)w);
1344         
1345         /* use */
1346         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1347         
1348         
1349         if (ibuf_other->rect_float) { /* from float to float */
1350                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1351         }
1352         else { /* from char to float */
1353                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1354         }
1355                 
1356 }
1357
1358 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1359 static float project_paint_uvpixel_mask(
1360         const ProjPaintState *ps,
1361         const int face_index,
1362         const int side,
1363         const float w[3])
1364 {
1365         float mask;
1366         
1367         /* Image Mask */
1368         if (ps->do_layer_stencil) {
1369                 /* another UV maps image is masking this one's */
1370                 ImBuf *ibuf_other;
1371                 Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_stencil, face_index);
1372                 const MTFace *tf_other = ps->dm_mtface_stencil + face_index;
1373                 
1374                 if (other_tpage && (ibuf_other = BKE_image_get_ibuf(other_tpage, NULL))) {
1375                         /* BKE_image_get_ibuf - TODO - this may be slow */
1376                         unsigned char rgba_ub[4];
1377                         float rgba_f[4];
1378                         
1379                         project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, rgba_f);
1380                         
1381                         if (ibuf_other->rect_float) { /* from float to float */
1382                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) / 3.0f) * rgba_f[3];
1383                         }
1384                         else { /* from char to float */
1385                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) / (256 * 3.0f)) * (rgba_ub[3] / 256.0f);
1386                         }
1387                         
1388                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1389                                 mask = (1.0f - mask);
1390
1391                         if (mask == 0.0f) {
1392                                 return 0.0f;
1393                         }
1394                 }
1395                 else {
1396                         return 0.0f;
1397                 }
1398         }
1399         else {
1400                 mask = 1.0f;
1401         }
1402         
1403         /* calculate mask */
1404         if (ps->do_mask_normal) {
1405                 MFace *mf = ps->dm_mface + face_index;
1406                 short *no1, *no2, *no3;
1407                 float no[3], angle;
1408                 no1 = ps->dm_mvert[mf->v1].no;
1409                 if (side == 1) {
1410                         no2 = ps->dm_mvert[mf->v3].no;
1411                         no3 = ps->dm_mvert[mf->v4].no;
1412                 }
1413                 else {
1414                         no2 = ps->dm_mvert[mf->v2].no;
1415                         no3 = ps->dm_mvert[mf->v3].no;
1416                 }
1417                 
1418                 no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1419                 no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1420                 no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1421                 normalize_v3(no);
1422                 
1423                 /* now we can use the normal as a mask */
1424                 if (ps->is_ortho) {
1425                         angle = angle_normalized_v3v3((float *)ps->viewDir, no);
1426                 }
1427                 else {
1428                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1429                         float viewDirPersp[3];
1430                         float *co1, *co2, *co3;
1431                         co1 = ps->dm_mvert[mf->v1].co;
1432                         if (side == 1) {
1433                                 co2 = ps->dm_mvert[mf->v3].co;
1434                                 co3 = ps->dm_mvert[mf->v4].co;
1435                         }
1436                         else {
1437                                 co2 = ps->dm_mvert[mf->v2].co;
1438                                 co3 = ps->dm_mvert[mf->v3].co;
1439                         }
1440
1441                         /* Get the direction from the viewPoint to the pixel and normalize */
1442                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1443                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1444                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1445                         normalize_v3(viewDirPersp);
1446                         
1447                         angle = angle_normalized_v3v3(viewDirPersp, no);
1448                 }
1449                 
1450                 if (angle >= ps->normal_angle) {
1451                         return 0.0f; /* outsize the normal limit*/
1452                 }
1453                 else if (angle > ps->normal_angle_inner) {
1454                         mask *= (ps->normal_angle - angle) / ps->normal_angle_range;
1455                 } /* otherwise no mask normal is needed, were within the limit */
1456         }
1457         
1458         // This only works when the opacity dosnt change while painting, stylus pressure messes with this
1459         // so don't use it.
1460         // if (ps->is_airbrush==0) mask *= BKE_brush_alpha_get(ps->brush);
1461         
1462         return mask;
1463 }
1464
1465 /* run this function when we know a bucket's, face's pixel can be initialized,
1466  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1467 static ProjPixel *project_paint_uvpixel_init(
1468         const ProjPaintState *ps,
1469         MemArena *arena,
1470         const ImBuf *ibuf,
1471         short x_px, short y_px,
1472         const float mask,
1473         const int face_index,
1474         const int image_index,
1475         const float pixelScreenCo[4],
1476         const int side,
1477         const float w[3])
1478 {
1479         ProjPixel *projPixel;
1480         short size;
1481         
1482         /* wrap pixel location */
1483         x_px = x_px % ibuf->x;
1484         if (x_px < 0) x_px += ibuf->x;
1485         y_px = y_px % ibuf->y;
1486         if (y_px < 0) y_px += ibuf->y;
1487         
1488         if (ps->tool == PAINT_TOOL_CLONE) {
1489                 size = sizeof(ProjPixelClone);
1490         }
1491         else if (ps->tool == PAINT_TOOL_SMEAR) {
1492                 size = sizeof(ProjPixelClone);
1493         }
1494         else {
1495                 size = sizeof(ProjPixel);
1496         }
1497         
1498         projPixel = (ProjPixel *)BLI_memarena_alloc(arena, size);
1499         //memset(projPixel, 0, size);
1500         
1501         if (ibuf->rect_float) {
1502                 projPixel->pixel.f_pt = (float *)ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1503                 projPixel->origColor.f[0] = projPixel->newColor.f[0] = projPixel->pixel.f_pt[0];  
1504                 projPixel->origColor.f[1] = projPixel->newColor.f[1] = projPixel->pixel.f_pt[1];  
1505                 projPixel->origColor.f[2] = projPixel->newColor.f[2] = projPixel->pixel.f_pt[2];  
1506                 projPixel->origColor.f[3] = projPixel->newColor.f[3] = projPixel->pixel.f_pt[3];  
1507         }
1508         else {
1509                 projPixel->pixel.ch_pt = ((unsigned char *)ibuf->rect + ((x_px + y_px * ibuf->x) * 4));
1510                 projPixel->origColor.uint = projPixel->newColor.uint = *projPixel->pixel.uint_pt;
1511         }
1512         
1513         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1514         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1515         
1516         projPixel->x_px = x_px;
1517         projPixel->y_px = y_px;
1518         
1519         projPixel->mask = (unsigned short)(mask * 65535);
1520         projPixel->mask_max = 0;
1521         
1522         /* which bounding box cell are we in?, needed for undo */
1523         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1524                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1525         
1526         /* done with view3d_project_float inline */
1527         if (ps->tool == PAINT_TOOL_CLONE) {
1528                 if (ps->dm_mtface_clone) {
1529                         ImBuf *ibuf_other;
1530                         Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_clone, face_index);
1531                         const MTFace *tf_other = ps->dm_mtface_clone + face_index;
1532                         
1533                         if (other_tpage && (ibuf_other = BKE_image_get_ibuf(other_tpage, NULL))) {
1534                                 /* BKE_image_get_ibuf - TODO - this may be slow */
1535                                 
1536                                 if (ibuf->rect_float) {
1537                                         if (ibuf_other->rect_float) { /* from float to float */
1538                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1539                                         }
1540                                         else { /* from char to float */
1541                                                 unsigned char rgba_ub[4];
1542                                                 project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, NULL);
1543                                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(((ProjPixelClone *)projPixel)->clonepx.f, rgba_ub);
1544                                         }
1545                                 }
1546                                 else {
1547                                         if (ibuf_other->rect_float) { /* float to char */
1548                                                 float rgba[4];
1549                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, rgba);
1550                                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1551                                         }
1552                                         else { /* char to char */
1553                                                 project_face_pixel(tf_other, ibuf_other, w, side, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1554                                         }
1555                                 }
1556                         }
1557                         else {
1558                                 if (ibuf->rect_float) {
1559                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1560                                 }
1561                                 else {
1562                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1563                                 }
1564                         }
1565                         
1566                 }
1567                 else {
1568                         float co[2];
1569                         sub_v2_v2v2(co, projPixel->projCoSS, (float *)ps->cloneOffset);
1570                         
1571                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1572                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1573                         if (ibuf->rect_float) {
1574                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1575                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1576                                 }
1577                         }
1578                         else {
1579                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1580                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1581                                 }
1582                         }
1583                 }
1584         }
1585         
1586 #ifdef PROJ_DEBUG_PAINT
1587         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1588         else                  projPixel->pixel.ch_pt[0] = 0;
1589 #endif
1590         projPixel->image_index = image_index;
1591         
1592         return projPixel;
1593 }
1594
1595 static int line_clip_rect2f(
1596         rctf *rect,
1597         const float l1[2], const float l2[2],
1598         float l1_clip[2], float l2_clip[2])
1599 {
1600         /* first account for horizontal, then vertical lines */
1601         /* horiz */
1602         if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) {
1603                 /* is the line out of range on its Y axis? */
1604                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1605                         return 0;
1606                 }
1607                 /* line is out of range on its X axis */
1608                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1609                         return 0;
1610                 }
1611                 
1612                 
1613                 if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1614                         if (BLI_in_rctf(rect, l1[0], l1[1])) {
1615                                 copy_v2_v2(l1_clip, l1);
1616                                 copy_v2_v2(l2_clip, l2);
1617                                 return 1;
1618                         }
1619                         else {
1620                                 return 0;
1621                         }
1622                 }
1623                 
1624                 copy_v2_v2(l1_clip, l1);
1625                 copy_v2_v2(l2_clip, l2);
1626                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1627                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1628                 return 1;
1629         }
1630         else if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) {
1631                 /* is the line out of range on its X axis? */
1632                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1633                         return 0;
1634                 }
1635                 
1636                 /* line is out of range on its Y axis */
1637                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1638                         return 0;
1639                 }
1640                 
1641                 if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1642                         if (BLI_in_rctf(rect, l1[0], l1[1])) {
1643                                 copy_v2_v2(l1_clip, l1);
1644                                 copy_v2_v2(l2_clip, l2);
1645                                 return 1;
1646                         }
1647                         else {
1648                                 return 0;
1649                         }
1650                 }
1651                 
1652                 copy_v2_v2(l1_clip, l1);
1653                 copy_v2_v2(l2_clip, l2);
1654                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1655                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1656                 return 1;
1657         }
1658         else {
1659                 float isect;
1660                 short ok1 = 0;
1661                 short ok2 = 0;
1662                 
1663                 /* Done with vertical lines */
1664                 
1665                 /* are either of the points inside the rectangle ? */
1666                 if (BLI_in_rctf(rect, l1[0], l1[1])) {
1667                         copy_v2_v2(l1_clip, l1);
1668                         ok1 = 1;
1669                 }
1670                 
1671                 if (BLI_in_rctf(rect, l2[0], l2[1])) {
1672                         copy_v2_v2(l2_clip, l2);
1673                         ok2 = 1;
1674                 }
1675                 
1676                 /* line inside rect */
1677                 if (ok1 && ok2) return 1;
1678                 
1679                 /* top/bottom */
1680                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1681                         if (l1[1] < l2[1]) { /* line 1 is outside */
1682                                 l1_clip[0] = isect;
1683                                 l1_clip[1] = rect->ymin;
1684                                 ok1 = 1;
1685                         }
1686                         else {
1687                                 l2_clip[0] = isect;
1688                                 l2_clip[1] = rect->ymin;
1689                                 ok2 = 2;
1690                         }
1691                 }
1692                 
1693                 if (ok1 && ok2) return 1;
1694                 
1695                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1696                         if (l1[1] > l2[1]) { /* line 1 is outside */
1697                                 l1_clip[0] = isect;
1698                                 l1_clip[1] = rect->ymax;
1699                                 ok1 = 1;
1700                         }
1701                         else {
1702                                 l2_clip[0] = isect;
1703                                 l2_clip[1] = rect->ymax;
1704                                 ok2 = 2;
1705                         }
1706                 }
1707                 
1708                 if (ok1 && ok2) return 1;
1709                 
1710                 /* left/right */
1711                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1712                         if (l1[0] < l2[0]) { /* line 1 is outside */
1713                                 l1_clip[0] = rect->xmin;
1714                                 l1_clip[1] = isect;
1715                                 ok1 = 1;
1716                         }
1717                         else {
1718                                 l2_clip[0] = rect->xmin;
1719                                 l2_clip[1] = isect;
1720                                 ok2 = 2;
1721                         }
1722                 }
1723         
1724                 if (ok1 && ok2) return 1;
1725                 
1726                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1727                         if (l1[0] > l2[0]) { /* line 1 is outside */
1728                                 l1_clip[0] = rect->xmax;
1729                                 l1_clip[1] = isect;
1730                                 ok1 = 1;
1731                         }
1732                         else {
1733                                 l2_clip[0] = rect->xmax;
1734                                 l2_clip[1] = isect;
1735                                 ok2 = 2;
1736                         }
1737                 }
1738                 
1739                 if (ok1 && ok2) {
1740                         return 1;
1741                 }
1742                 else {
1743                         return 0;
1744                 }
1745         }
1746 }
1747
1748
1749
1750 /* scale the quad & tri about its center
1751  * scaling by PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1752  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces */
1753 #ifndef PROJ_DEBUG_NOSEAMBLEED
1754 static void scale_quad(float insetCos[4][3], float *origCos[4], const float inset)
1755 {
1756         float cent[3];
1757         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0] + origCos[3][0]) / 4.0f;
1758         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1] + origCos[3][1]) / 4.0f;
1759         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2] + origCos[3][2]) / 4.0f;
1760         
1761         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1762         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1763         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1764         sub_v3_v3v3(insetCos[3], origCos[3], cent);
1765         
1766         mul_v3_fl(insetCos[0], inset);
1767         mul_v3_fl(insetCos[1], inset);
1768         mul_v3_fl(insetCos[2], inset);
1769         mul_v3_fl(insetCos[3], inset);
1770         
1771         add_v3_v3(insetCos[0], cent);
1772         add_v3_v3(insetCos[1], cent);
1773         add_v3_v3(insetCos[2], cent);
1774         add_v3_v3(insetCos[3], cent);
1775 }
1776
1777
1778 static void scale_tri(float insetCos[4][3], float *origCos[4], const float inset)
1779 {
1780         float cent[3];
1781         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) / 3.0f;
1782         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) / 3.0f;
1783         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) / 3.0f;
1784         
1785         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1786         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1787         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1788         
1789         mul_v3_fl(insetCos[0], inset);
1790         mul_v3_fl(insetCos[1], inset);
1791         mul_v3_fl(insetCos[2], inset);
1792         
1793         add_v3_v3(insetCos[0], cent);
1794         add_v3_v3(insetCos[1], cent);
1795         add_v3_v3(insetCos[2], cent);
1796 }
1797 #endif //PROJ_DEBUG_NOSEAMBLEED
1798
1799 static float len_squared_v2v2_alt(const float *v1, const float v2_1, const float v2_2)
1800 {
1801         float x, y;
1802
1803         x = v1[0] - v2_1;
1804         y = v1[1] - v2_2;
1805         return x * x + y * y;
1806 }
1807
1808 /* note, use a squared value so we can use len_squared_v2v2
1809  * be sure that you have done a bounds check first or this may fail */
1810 /* only give bucket_bounds as an arg because we need it elsewhere */
1811 static int project_bucket_isect_circle(const float cent[2], const float radius_squared, rctf *bucket_bounds)
1812 {
1813          
1814         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect 
1815          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1816          * this is even less work then an intersection test
1817          */
1818 #if 0
1819         if (BLI_in_rctf(bucket_bounds, cent[0], cent[1]))
1820                 return 1;
1821 #endif
1822         
1823         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1824             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1825         {
1826                 return 1;
1827         }
1828         
1829         /* out of bounds left */
1830         if (cent[0] < bucket_bounds->xmin) {
1831                 /* lower left out of radius test */
1832                 if (cent[1] < bucket_bounds->ymin) {
1833                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1834                 } 
1835                 /* top left test */
1836                 else if (cent[1] > bucket_bounds->ymax) {
1837                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1838                 }
1839         }
1840         else if (cent[0] > bucket_bounds->xmax) {
1841                 /* lower right out of radius test */
1842                 if (cent[1] < bucket_bounds->ymin) {
1843                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1844                 } 
1845                 /* top right test */
1846                 else if (cent[1] > bucket_bounds->ymax) {
1847                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1848                 }
1849         }
1850         
1851         return 0;
1852 }
1853
1854
1855
1856 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1857  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1858  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1859  * (viewed from the side)
1860  * 
1861  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1862  * funcs that only account for points inside the triangle.
1863  * however switching back to this for ortho is always an option */
1864
1865 static void rect_to_uvspace_ortho(
1866         rctf *bucket_bounds,
1867         float *v1coSS, float *v2coSS, float *v3coSS,
1868         float *uv1co, float *uv2co, float *uv3co,
1869         float bucket_bounds_uv[4][2],
1870         const int flip)
1871 {
1872         float uv[2];
1873         float w[3];
1874         
1875         /* get the UV space bounding box */
1876         uv[0] = bucket_bounds->xmax;
1877         uv[1] = bucket_bounds->ymin;
1878         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1879         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1880
1881         //uv[0] = bucket_bounds->xmax; // set above
1882         uv[1] = bucket_bounds->ymax;
1883         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1884         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1885
1886         uv[0] = bucket_bounds->xmin;
1887         //uv[1] = bucket_bounds->ymax; // set above
1888         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1889         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1890
1891         //uv[0] = bucket_bounds->xmin; // set above
1892         uv[1] = bucket_bounds->ymin;
1893         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1894         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1895 }
1896
1897 /* same as above but use barycentric_weights_v2_persp */
1898 static void rect_to_uvspace_persp(
1899         rctf *bucket_bounds,
1900         float *v1coSS, float *v2coSS, float *v3coSS,
1901         float *uv1co, float *uv2co, float *uv3co,
1902         float bucket_bounds_uv[4][2],
1903         const int flip
1904         )
1905 {
1906         float uv[2];
1907         float w[3];
1908         
1909         /* get the UV space bounding box */
1910         uv[0] = bucket_bounds->xmax;
1911         uv[1] = bucket_bounds->ymin;
1912         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1913         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1914
1915         //uv[0] = bucket_bounds->xmax; // set above
1916         uv[1] = bucket_bounds->ymax;
1917         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1918         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1919
1920         uv[0] = bucket_bounds->xmin;
1921         //uv[1] = bucket_bounds->ymax; // set above
1922         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1923         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1924
1925         //uv[0] = bucket_bounds->xmin; // set above
1926         uv[1] = bucket_bounds->ymin;
1927         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1928         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1929 }
1930
1931 /* This works as we need it to but we can save a few steps and not use it */
1932
1933 #if 0
1934 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
1935 {
1936         float v1[2], v2[2];
1937         
1938         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
1939         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
1940         
1941         return -atan2(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
1942 }
1943 #endif
1944
1945 #define ISECT_1 (1)
1946 #define ISECT_2 (1 << 1)
1947 #define ISECT_3 (1 << 2)
1948 #define ISECT_4 (1 << 3)
1949 #define ISECT_ALL3 ((1 << 3) - 1)
1950 #define ISECT_ALL4 ((1 << 4) - 1)
1951
1952 /* limit must be a fraction over 1.0f */
1953 static int IsectPT2Df_limit(float pt[2], float v1[2], float v2[2], float v3[2], float limit)
1954 {
1955         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;
1956 }
1957
1958 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
1959  * so we have the clipped UV's to do pixel intersection tests with 
1960  * */
1961 static int float_z_sort_flip(const void *p1, const void *p2)
1962 {
1963         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
1964 }
1965
1966 static int float_z_sort(const void *p1, const void *p2)
1967 {
1968         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
1969 }
1970
1971 static void project_bucket_clip_face(
1972         const int is_ortho,
1973         rctf *bucket_bounds,
1974         float *v1coSS, float *v2coSS, float *v3coSS,
1975         float *uv1co, float *uv2co, float *uv3co,
1976         float bucket_bounds_uv[8][2],
1977         int *tot)
1978 {
1979         int inside_bucket_flag = 0;
1980         int inside_face_flag = 0;
1981         const int flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
1982         
1983         float bucket_bounds_ss[4][2];
1984
1985         /* get the UV space bounding box */
1986         inside_bucket_flag |= BLI_in_rctf(bucket_bounds, v1coSS[0], v1coSS[1]);
1987         inside_bucket_flag |= BLI_in_rctf(bucket_bounds, v2coSS[0], v2coSS[1]) << 1;
1988         inside_bucket_flag |= BLI_in_rctf(bucket_bounds, v3coSS[0], v3coSS[1]) << 2;
1989         
1990         if (inside_bucket_flag == ISECT_ALL3) {
1991                 /* all screenspace points are inside the bucket bounding box, this means we don't need to clip and can simply return the UVs */
1992                 if (flip) { /* facing the back? */
1993                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
1994                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1995                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
1996                 }
1997                 else {
1998                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
1999                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2000                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
2001                 }
2002                 
2003                 *tot = 3; 
2004                 return;
2005         }
2006         
2007         /* get the UV space bounding box */
2008         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
2009         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
2010         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
2011         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
2012         
2013         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
2014         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
2015         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
2016
2017         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
2018         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
2019         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
2020
2021         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
2022         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
2023         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
2024         
2025         if (inside_face_flag == ISECT_ALL4) {
2026                 /* bucket is totally inside the screenspace face, we can safely use weights */
2027                 
2028                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2029                 else rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2030                 
2031                 *tot = 4;
2032                 return;
2033         }
2034         else {
2035                 /* The Complicated Case! 
2036                  * 
2037                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
2038                  * 
2039                  * we need to make a convex polyline from the intersection between the screenspace face
2040                  * and the bucket bounds.
2041                  * 
2042                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
2043                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
2044                  * do a correct clipping on both shapes. */
2045                 
2046                 
2047                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
2048                 
2049                 
2050                 
2051                 /* Maximum possible 6 intersections when using a rectangle and triangle */
2052                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
2053                 float v1_clipSS[2], v2_clipSS[2];
2054                 float w[3];
2055                 
2056                 /* calc center*/
2057                 float cent[2] = {0.0f, 0.0f};
2058                 /*float up[2] = {0.0f, 1.0f};*/
2059                 int i;
2060                 short doubles;
2061                 
2062                 (*tot) = 0;
2063                 
2064                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
2065                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
2066                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
2067                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
2068
2069                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
2070                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
2071                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
2072                 
2073                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
2074                         if (line_clip_rect2f(bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
2075                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2076                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2077                         }
2078                 }
2079                 
2080                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
2081                         if (line_clip_rect2f(bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
2082                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2083                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2084                         }
2085                 }       
2086                 
2087                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
2088                         if (line_clip_rect2f(bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
2089                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2090                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2091                         }
2092                 }
2093                 
2094                 
2095                 if ((*tot) < 3) { /* no intersections to speak of */
2096                         *tot = 0;
2097                         return;
2098                 }
2099         
2100                 /* now we have all points we need, collect their angles and sort them clockwise */
2101                 
2102                 for (i = 0; i < (*tot); i++) {
2103                         cent[0] += isectVCosSS[i][0];
2104                         cent[1] += isectVCosSS[i][1];
2105                 }
2106                 cent[0] = cent[0] / (float)(*tot);
2107                 cent[1] = cent[1] / (float)(*tot);
2108                 
2109                 
2110                 
2111                 /* Collect angles for every point around the center point */
2112
2113                 
2114 #if 0   /* uses a few more cycles then the above loop */
2115                 for (i = 0; i < (*tot); i++) {
2116                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
2117                 }
2118 #endif
2119
2120                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
2121                 v1_clipSS[1] = cent[1] + 1.0f;
2122                 
2123                 for (i = 0; i < (*tot); i++) {
2124                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2125                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2126                         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]);
2127                 }
2128                 
2129                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
2130                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
2131                 
2132                 /* remove doubles */
2133                 /* first/last check */
2134                 if (fabsf(isectVCosSS[0][0] - isectVCosSS[(*tot) - 1][0]) < PROJ_GEOM_TOLERANCE &&
2135                     fabsf(isectVCosSS[0][1] - isectVCosSS[(*tot) - 1][1]) < PROJ_GEOM_TOLERANCE)
2136                 {
2137                         (*tot)--;
2138                 }
2139                 
2140                 /* its possible there is only a few left after remove doubles */
2141                 if ((*tot) < 3) {
2142                         // printf("removed too many doubles A\n");
2143                         *tot = 0;
2144                         return;
2145                 }
2146                 
2147                 doubles = TRUE;
2148                 while (doubles == TRUE) {
2149                         doubles = FALSE;
2150                         for (i = 1; i < (*tot); i++) {
2151                                 if (fabsf(isectVCosSS[i - 1][0] - isectVCosSS[i][0]) < PROJ_GEOM_TOLERANCE &&
2152                                     fabsf(isectVCosSS[i - 1][1] - isectVCosSS[i][1]) < PROJ_GEOM_TOLERANCE)
2153                                 {
2154                                         int j;
2155                                         for (j = i + 1; j < (*tot); j++) {
2156                                                 isectVCosSS[j - 1][0] = isectVCosSS[j][0];
2157                                                 isectVCosSS[j - 1][1] = isectVCosSS[j][1];
2158                                         }
2159                                         doubles = TRUE; /* keep looking for more doubles */
2160                                         (*tot)--;
2161                                 }
2162                         }
2163                 }
2164                 
2165                 /* its possible there is only a few left after remove doubles */
2166                 if ((*tot) < 3) {
2167                         // printf("removed too many doubles B\n");
2168                         *tot = 0;
2169                         return;
2170                 }
2171                 
2172                 
2173                 if (is_ortho) {
2174                         for (i = 0; i < (*tot); i++) {
2175                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2176                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2177                         }
2178                 }
2179                 else {
2180                         for (i = 0; i < (*tot); i++) {
2181                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2182                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2183                         }
2184                 }
2185         }
2186
2187 #ifdef PROJ_DEBUG_PRINT_CLIP
2188         /* include this at the bottom of the above function to debug the output */
2189
2190         {
2191                 /* If there are ever any problems, */
2192                 float test_uv[4][2];
2193                 int i;
2194                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2195                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2196                 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]);
2197                 
2198                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2199                 
2200                 printf("[");
2201                 for (i = 0; i < (*tot); i++) {
2202                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2203                 }
2204                 printf("]),\\\n");
2205         }
2206 #endif
2207 }
2208
2209 /*
2210  * # This script creates faces in a blender scene from printed data above.
2211  *
2212  * project_ls = [
2213  * ...(output from above block)...
2214  * ]
2215  *
2216  * from Blender import Scene, Mesh, Window, sys, Mathutils
2217  *
2218  * import bpy
2219  *
2220  * V = Mathutils.Vector
2221  *
2222  * def main():
2223  *     sce = bpy.data.scenes.active
2224  *     
2225  *     for item in project_ls:
2226  *         bb = item[0]
2227  *         uv = item[1]
2228  *         poly = item[2]
2229  *         
2230  *         me = bpy.data.meshes.new()
2231  *         ob = sce.objects.new(me)
2232  *         
2233  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2234  *         me.faces.extend([(0,1,2,3),])
2235  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2236  *         me.faces.extend([(4,5,6),])
2237  *         
2238  *         vs = [V(p).xyz for p in poly]
2239  *         print len(vs)
2240  *         l = len(me.verts)
2241  *         me.verts.extend(vs)
2242  *         
2243  *         i = l
2244  *         while i < len(me.verts):
2245  *             ii = i + 1
2246  *             if ii == len(me.verts):
2247  *                 ii = l
2248  *             me.edges.extend([i, ii])
2249  *             i += 1
2250  * 
2251  * if __name__ == '__main__':
2252  *     main()
2253  */
2254
2255
2256 #undef ISECT_1
2257 #undef ISECT_2
2258 #undef ISECT_3
2259 #undef ISECT_4
2260 #undef ISECT_ALL3
2261 #undef ISECT_ALL4
2262
2263         
2264 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2265  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2266 static int IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2267 {
2268         int i;
2269         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2270                 return 0;
2271         
2272         for (i = 1; i < tot; i++) {
2273                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2274                         return 0;
2275                 
2276         }
2277         
2278         return 1;
2279 }
2280 static int IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2281 {
2282         int i;
2283         int side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2284         
2285         for (i = 1; i < tot; i++) {
2286                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2287                         return 0;
2288                 
2289         }
2290         
2291         return 1;
2292 }
2293
2294 /* One of the most important function for projectiopn painting, since it selects the pixels to be added into each bucket.
2295  * initialize pixels from this face where it intersects with the bucket_index, optionally initialize pixels for removing seams */
2296 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)
2297 {
2298         /* Projection vars, to get the 3D locations into screen space  */
2299         MemArena *arena = ps->arena_mt[thread_index];
2300         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2301         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2302         
2303         const MFace *mf = ps->dm_mface + face_index;
2304         const MTFace *tf = ps->dm_mtface + face_index;
2305         
2306         /* UV/pixel seeking data */
2307         int x; /* Image X-Pixel */
2308         int y; /* Image Y-Pixel */
2309         float mask;
2310         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2311         
2312         int side;
2313         float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to mf->v1,2,3 or mf->v1,3,4 */
2314         
2315         float *vCo[4]; /* vertex screenspace coords */
2316         
2317         float w[3], wco[3];
2318         
2319         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to tf->uv[0],1,2 or tf->uv[0],2,3 */
2320         float pixelScreenCo[4];
2321         
2322         rcti bounds_px; /* ispace bounds */
2323         /* vars for getting uvspace bounds */
2324         
2325         float tf_uv_pxoffset[4][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2326         float xhalfpx, yhalfpx;
2327         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2328         
2329         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2330         
2331         int i1, i2, i3;
2332         
2333         float uv_clip[8][2];
2334         int uv_clip_tot;
2335         const short is_ortho = ps->is_ortho;
2336         const short do_backfacecull = ps->do_backfacecull;
2337         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2338         
2339         vCo[0] = ps->dm_mvert[mf->v1].co;
2340         vCo[1] = ps->dm_mvert[mf->v2].co;
2341         vCo[2] = ps->dm_mvert[mf->v3].co;
2342         
2343         
2344         /* Use tf_uv_pxoffset instead of tf->uv so we can offset the UV half a pixel
2345          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2346          * problems when wrapping negative coords */
2347         xhalfpx = (0.5f +   (PROJ_GEOM_TOLERANCE / 3.0f)   ) / ibuf_xf;
2348         yhalfpx = (0.5f +   (PROJ_GEOM_TOLERANCE / 4.0f)   ) / ibuf_yf;
2349         
2350         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2351          * Needed to add this offset since UV coords are often quads aligned to pixels.
2352          * In this case pixels can be exactly between 2 triangles causing nasty
2353          * artifacts.
2354          * 
2355          * This workaround can be removed and painting will still work on most cases
2356          * but since the first thing most people try is painting onto a quad- better make it work.
2357          */
2358
2359
2360
2361         tf_uv_pxoffset[0][0] = tf->uv[0][0] - xhalfpx;
2362         tf_uv_pxoffset[0][1] = tf->uv[0][1] - yhalfpx;
2363
2364         tf_uv_pxoffset[1][0] = tf->uv[1][0] - xhalfpx;
2365         tf_uv_pxoffset[1][1] = tf->uv[1][1] - yhalfpx;
2366         
2367         tf_uv_pxoffset[2][0] = tf->uv[2][0] - xhalfpx;
2368         tf_uv_pxoffset[2][1] = tf->uv[2][1] - yhalfpx;  
2369         
2370         if (mf->v4) {
2371                 vCo[3] = ps->dm_mvert[mf->v4].co;
2372                 
2373                 tf_uv_pxoffset[3][0] = tf->uv[3][0] - xhalfpx;
2374                 tf_uv_pxoffset[3][1] = tf->uv[3][1] - yhalfpx;
2375                 side = 1;
2376         }
2377         else {
2378                 side = 0;
2379         }
2380         
2381         do {
2382                 if (side == 1) {
2383                         i1 = 0; i2 = 2; i3 = 3;
2384                 }
2385                 else {
2386                         i1 = 0; i2 = 1; i3 = 2;
2387                 }
2388                 
2389                 uv1co = tf_uv_pxoffset[i1]; // was tf->uv[i1];
2390                 uv2co = tf_uv_pxoffset[i2]; // was tf->uv[i2];
2391                 uv3co = tf_uv_pxoffset[i3]; // was tf->uv[i3];
2392
2393                 v1coSS = ps->screenCoords[(*(&mf->v1 + i1))];
2394                 v2coSS = ps->screenCoords[(*(&mf->v1 + i2))];
2395                 v3coSS = ps->screenCoords[(*(&mf->v1 + i3))];
2396                 
2397                 /* This funtion gives is a concave polyline in UV space from the clipped quad and tri*/
2398                 project_bucket_clip_face(
2399                         is_ortho, bucket_bounds,
2400                         v1coSS, v2coSS, v3coSS,
2401                         uv1co, uv2co, uv3co,
2402                         uv_clip, &uv_clip_tot
2403                         );
2404
2405                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2406 #if 0
2407                 if (uv_clip_tot > 6) {
2408                         printf("this should never happen! %d\n", uv_clip_tot);
2409                 }
2410 #endif
2411
2412                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2413
2414                         if (clamp_u) {
2415                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2416                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2417                         }
2418
2419                         if (clamp_v) {
2420                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2421                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2422                         }
2423
2424                         /* clip face and */
2425                         
2426                         has_isect = 0;
2427                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2428                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2429                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2430
2431                                 has_x_isect = 0;
2432                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2433                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2434                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2435                                         
2436                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2437                                          * could check the poly direction but better to do this */
2438                                         if ((do_backfacecull == TRUE  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2439                                             (do_backfacecull == FALSE && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2440                                         {
2441                                                 
2442                                                 has_x_isect = has_isect = 1;
2443                                                 
2444                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2445                                                 else          screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2446                                                 
2447                                                 /* a pity we need to get the worldspace pixel location here */
2448                                                 if (do_clip) {
2449                                                         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);
2450                                                         if (ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2451                                                                 continue; /* Watch out that no code below this needs to run */
2452                                                         }
2453                                                 }
2454                                                 
2455                                                 /* Is this UV visible from the view? - raytrace */
2456                                                 /* project_paint_PickFace is less complex, use for testing */
2457                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == face_index) {
2458                                                 if ((ps->do_occlude == FALSE) ||
2459                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2460                                                 {
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 == FALSE) ||
2637                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2638                                                                                 {
2639                                                                                         /* Only bother calculating the weights if we intersect */
2640                                                                                         if (ps->do_mask_normal || ps->dm_mtface_clone) {
2641 #if 1
2642                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2643                                                                                                 float uv_close[2];
2644                                                                                                 float fac = closest_to_line_v2(uv_close, uv, tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2]);
2645                                                                                                 if      (fac < 0.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx1]);
2646                                                                                                 else if (fac > 1.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx2]);
2647
2648                                                                                                 if (side) {
2649                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[2], tf_uv_pxoffset[3], uv_close, w);
2650                                                                                                 }
2651                                                                                                 else {
2652                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[1], tf_uv_pxoffset[2], uv_close, w);
2653                                                                                                 }
2654 #else                                                                                   /* this is buggy with quads, don't use for now */
2655
2656                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2657                                                                                                 fac = fac1 + (fac * (fac2 - fac1));
2658
2659                                                                                                 w[0] = w[1] = w[2] = 0.0;
2660                                                                                                 if (side) {
2661                                                                                                         w[fidx1 ? fidx1 - 1 : 0] = 1.0f - fac;
2662                                                                                                         w[fidx2 ? fidx2 - 1 : 0] = fac;
2663                                                                                                 }
2664                                                                                                 else {
2665                                                                                                         w[fidx1] = 1.0f - fac;
2666                                                                                                         w[fidx2] = fac;
2667                                                                                                 }
2668 #endif
2669                                                                                         }
2670                                                                                         
2671                                                                                         /* a pity we need to get the worldspace pixel location here */
2672                                                                                         if (do_clip) {
2673                                                                                                 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);
2674                                                                                                 else      interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
2675
2676                                                                                                 if (ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2677                                                                                                         continue; /* Watch out that no code below this needs to run */
2678                                                                                                 }
2679                                                                                         }
2680                                                                                         
2681                                                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2682                                                                                         
2683                                                                                         if (mask > 0.0f) {
2684                                                                                                 BLI_linklist_prepend_arena(
2685                                                                                                         bucketPixelNodes,
2686                                                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index, image_index, pixelScreenCo, side, w),
2687                                                                                                         arena
2688                                                                                                         );
2689                                                                                         }
2690                                                                                         
2691                                                                                 }
2692                                                                         }
2693                                                                         else if (has_x_isect) {
2694                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2695                                                                                 break;
2696                                                                         }
2697                                                                 }
2698                                                                 
2699 #if 0                           /* TODO - investigate why this dosnt work sometimes! it should! */
2700                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2701                                                                 if (has_x_isect == 0 && has_isect) {
2702                                                                         break;
2703                                                                 }
2704 #endif
2705                                                         }
2706                                                 }
2707                                         }
2708                                 }
2709                         }
2710                 }
2711         }
2712 #endif // PROJ_DEBUG_NOSEAMBLEED
2713 }
2714
2715
2716 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2717 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2718 {
2719         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2720         /* 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 */
2721         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 */
2722         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2723         
2724         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2725         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2726         
2727         /* in case the rect is outside the mesh 2d bounds */
2728         CLAMP(bucketMin[0], 0, ps->buckets_x);
2729         CLAMP(bucketMin[1], 0, ps->buckets_y);
2730         
2731         CLAMP(bucketMax[0], 0, ps->buckets_x);
2732         CLAMP(bucketMax[1], 0, ps->buckets_y);
2733 }
2734
2735 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2736 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2737 {
2738         bucket_bounds->xmin = ps->screenMin[0] + ((bucket_x) * (ps->screen_width / ps->buckets_x));     /* left */
2739         bucket_bounds->xmax = ps->screenMin[0] + ((bucket_x + 1) * (ps->screen_width / ps->buckets_x)); /* right */
2740         
2741         bucket_bounds->ymin = ps->screenMin[1] + ((bucket_y) * (ps->screen_height / ps->buckets_y));      /* bottom */
2742         bucket_bounds->ymax = ps->screenMin[1] + ((bucket_y + 1) * (ps->screen_height  / ps->buckets_y)); /* top */
2743 }
2744
2745 /* Fill this bucket with pixels from the faces that intersect it.
2746  * 
2747  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2748 static void project_bucket_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, rctf *bucket_bounds)
2749 {
2750         LinkNode *node;
2751         int face_index, image_index = 0;
2752         ImBuf *ibuf = NULL;
2753         Image *tpage_last = NULL, *tpage;
2754         Image *ima = NULL;
2755
2756         if (ps->image_tot == 1) {
2757                 /* Simple loop, no context switching */
2758                 ibuf = ps->projImages[0].ibuf;
2759                 ima = ps->projImages[0].ima;
2760
2761                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2762                         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);
2763                 }
2764         }
2765         else {
2766                 
2767                 /* More complicated loop, switch between images */
2768                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2769                         face_index = GET_INT_FROM_POINTER(node->link);
2770                                 
2771                         /* Image context switching */
2772                         tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
2773                         if (tpage_last != tpage) {
2774                                 tpage_last = tpage;
2775
2776                                 for (image_index = 0; image_index < ps->image_tot; image_index++) {
2777                                         if (ps->projImages[image_index].ima == tpage_last) {
2778                                                 ibuf = ps->projImages[image_index].ibuf;
2779                                                 ima = ps->projImages[image_index].ima;
2780                                                 break;
2781                                         }
2782                                 }
2783                         }
2784                         /* context switching done */
2785                         
2786                         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);
2787                 }
2788         }
2789         
2790         ps->bucketFlags[bucket_index] |= PROJ_BUCKET_INIT;
2791 }
2792
2793
2794 /* We want to know if a bucket and a face overlap in screen-space
2795  * 
2796  * Note, if this ever returns false positives its not that bad, since a face in the bounding area will have its pixels
2797  * calculated when it might not be needed later, (at the moment at least)
2798  * obviously it shouldn't have bugs though */
2799
2800 static int project_bucket_face_isect(ProjPaintState *ps, int bucket_x, int bucket_y, const MFace *mf)
2801 {
2802         /* TODO - replace this with a tricker method that uses sideofline for all screenCoords's edges against the closest bucket corner */
2803         rctf bucket_bounds;
2804         float p1[2], p2[2], p3[2], p4[2];
2805         float *v, *v1, *v2, *v3, *v4 = NULL;
2806         int fidx;
2807         
2808         project_bucket_bounds(ps, bucket_x, bucket_y, &bucket_bounds);
2809         
2810         /* Is one of the faces verts in the bucket bounds? */
2811         
2812         fidx = mf->v4 ? 3 : 2;
2813         do {
2814                 v = ps->screenCoords[(*(&mf->v1 + fidx))];
2815                 if (BLI_in_rctf(&bucket_bounds, v[0], v[1])) {
2816                         return 1;
2817                 }
2818         } while (fidx--);
2819         
2820         v1 = ps->screenCoords[mf->v1];
2821         v2 = ps->screenCoords[mf->v2];
2822         v3 = ps->screenCoords[mf->v3];
2823         if (mf->v4) {
2824                 v4 = ps->screenCoords[mf->v4];
2825         }
2826         
2827         p1[0] = bucket_bounds.xmin; p1[1] = bucket_bounds.ymin;
2828         p2[0] = bucket_bounds.xmin; p2[1] = bucket_bounds.ymax;
2829         p3[0] = bucket_bounds.xmax; p3[1] = bucket_bounds.ymax;
2830         p4[0] = bucket_bounds.xmax; p4[1] = bucket_bounds.ymin;
2831                 
2832         if (mf->v4) {
2833                 if (isect_point_quad_v2(p1, v1, v2, v3, v4) ||
2834                     isect_point_quad_v2(p2, v1, v2, v3, v4) ||
2835                     isect_point_quad_v2(p3, v1, v2, v3, v4) ||
2836                     isect_point_quad_v2(p4, v1, v2, v3, v4) ||
2837
2838                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2839                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3) || isect_line_line_v2(p1, p2, v3, v4)) ||
2840                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3) || isect_line_line_v2(p2, p3, v3, v4)) ||
2841                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3) || isect_line_line_v2(p3, p4, v3, v4)) ||
2842                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3) || isect_line_line_v2(p4, p1, v3, v4)))
2843                 {
2844                         return 1;
2845                 }
2846         }
2847         else {
2848                 if (isect_point_tri_v2(p1, v1, v2, v3) ||
2849                     isect_point_tri_v2(p2, v1, v2, v3) ||
2850                     isect_point_tri_v2(p3, v1, v2, v3) ||
2851                     isect_point_tri_v2(p4, v1, v2, v3) ||
2852                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2853                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3)) ||
2854                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3)) ||
2855                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3)) ||
2856                     (isect_line_line_v2(p4, p1, v1, v2)