Merging r50192 through r50223 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 "IMB_colormanagement.h"
108
109 #include "paint_intern.h"
110
111 /* Defines and Structs */
112
113 #define IMAPAINT_CHAR_TO_FLOAT(c) ((c) / 255.0f)
114
115 #define IMAPAINT_FLOAT_RGB_TO_CHAR(c, f)  {                                   \
116         (c)[0]= FTOCHAR((f)[0]);                                                  \
117         (c)[1]= FTOCHAR((f)[1]);                                                  \
118         (c)[2]= FTOCHAR((f)[2]);                                                  \
119 } (void)0
120 #define IMAPAINT_FLOAT_RGBA_TO_CHAR(c, f)  {                                  \
121         (c)[0]= FTOCHAR((f)[0]);                                                  \
122         (c)[1]= FTOCHAR((f)[1]);                                                  \
123         (c)[2]= FTOCHAR((f)[2]);                                                  \
124         (c)[3]= FTOCHAR((f)[3]);                                                  \
125 } (void)0
126 #define IMAPAINT_CHAR_RGB_TO_FLOAT(f, c)  {                                   \
127         (f)[0]= IMAPAINT_CHAR_TO_FLOAT((c)[0]);                                   \
128         (f)[1]= IMAPAINT_CHAR_TO_FLOAT((c)[1]);                                   \
129         (f)[2]= IMAPAINT_CHAR_TO_FLOAT((c)[2]);                                   \
130 } (void)0
131 #define IMAPAINT_CHAR_RGBA_TO_FLOAT(f, c)  {                                  \
132         (f)[0]= IMAPAINT_CHAR_TO_FLOAT((c)[0]);                                   \
133         (f)[1]= IMAPAINT_CHAR_TO_FLOAT((c)[1]);                                   \
134         (f)[2]= IMAPAINT_CHAR_TO_FLOAT((c)[2]);                                   \
135         (f)[3]= IMAPAINT_CHAR_TO_FLOAT((c)[3]);                                   \
136 } (void)0
137
138 #define IMAPAINT_FLOAT_RGB_COPY(a, b) copy_v3_v3(a, b)
139
140 #define IMAPAINT_TILE_BITS          6
141 #define IMAPAINT_TILE_SIZE          (1 << IMAPAINT_TILE_BITS)
142 #define IMAPAINT_TILE_NUMBER(size)  (((size) + IMAPAINT_TILE_SIZE - 1) >> IMAPAINT_TILE_BITS)
143
144 static void imapaint_image_update(SpaceImage *sima, Image *image, ImBuf *ibuf, short texpaint);
145
146
147 typedef struct ImagePaintState {
148         SpaceImage *sima;
149         View2D *v2d;
150         Scene *scene;
151         bScreen *screen;
152
153         Brush *brush;
154         short tool, blend;
155         Image *image;
156         ImBuf *canvas;
157         ImBuf *clonecanvas;
158         short clonefreefloat;
159         char *warnpackedfile;
160         char *warnmultifile;
161
162         /* viewport texture paint only, but _not_ project paint */
163         Object *ob;
164         int faceindex;
165         float uv[2];
166         int do_facesel;
167
168         DerivedMesh    *dm;
169         int             dm_totface;
170         int             dm_release;
171
172         MFace          *dm_mface;
173         MTFace         *dm_mtface;
174 } ImagePaintState;
175
176 typedef struct ImagePaintPartialRedraw {
177         int x1, y1, x2, y2;
178         int enabled;
179 } ImagePaintPartialRedraw;
180
181 typedef struct ImagePaintRegion {
182         int destx, desty;
183         int srcx, srcy;
184         int width, height;
185 } ImagePaintRegion;
186
187 /* ProjectionPaint defines */
188
189 /* approx the number of buckets to have under the brush,
190  * used with the brush size to set the ps->buckets_x and ps->buckets_y value.
191  * 
192  * When 3 - a brush should have ~9 buckets under it at once
193  * ...this helps for threading while painting as well as
194  * avoiding initializing pixels that wont touch the brush */
195 #define PROJ_BUCKET_BRUSH_DIV 4
196
197 #define PROJ_BUCKET_RECT_MIN 4
198 #define PROJ_BUCKET_RECT_MAX 256
199
200 #define PROJ_BOUNDBOX_DIV 8
201 #define PROJ_BOUNDBOX_SQUARED  (PROJ_BOUNDBOX_DIV * PROJ_BOUNDBOX_DIV)
202
203 //#define PROJ_DEBUG_PAINT 1
204 //#define PROJ_DEBUG_NOSEAMBLEED 1
205 //#define PROJ_DEBUG_PRINT_CLIP 1
206 #define PROJ_DEBUG_WINCLIP 1
207
208 /* projectFaceSeamFlags options */
209 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
210 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
211 #define PROJ_FACE_SEAM1 (1 << 0)  /* If this face has a seam on any of its edges */
212 #define PROJ_FACE_SEAM2 (1 << 1)
213 #define PROJ_FACE_SEAM3 (1 << 2)
214 #define PROJ_FACE_SEAM4 (1 << 3)
215
216 #define PROJ_FACE_NOSEAM1   (1 << 4)
217 #define PROJ_FACE_NOSEAM2   (1 << 5)
218 #define PROJ_FACE_NOSEAM3   (1 << 6)
219 #define PROJ_FACE_NOSEAM4   (1 << 7)
220
221 #define PROJ_SRC_VIEW       1
222 #define PROJ_SRC_IMAGE_CAM  2
223 #define PROJ_SRC_IMAGE_VIEW 3
224
225 #define PROJ_VIEW_DATA_ID "view_data"
226 #define PROJ_VIEW_DATA_SIZE (4 * 4 + 4 * 4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
227
228
229 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
230  * as this number approaches  1.0f the likelihood increases of float precision errors where
231  * it is occluded by an adjacent face */
232 #define PROJ_FACE_SCALE_SEAM    0.99f
233
234 #define PROJ_BUCKET_NULL        0
235 #define PROJ_BUCKET_INIT        (1 << 0)
236 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
237
238 /* used for testing doubles, if a point is on a line etc */
239 #define PROJ_GEOM_TOLERANCE 0.00075f
240
241 /* vert flags */
242 #define PROJ_VERT_CULL 1
243
244 #define PI_80_DEG ((M_PI_2 / 9) * 8)
245
246 /* This is mainly a convenience struct used so we can keep an array of images we use
247  * Thir imbufs, etc, in 1 array, When using threads this array is copied for each thread
248  * because 'partRedrawRect' and 'touch' values would not be thread safe */
249 typedef struct ProjPaintImage {
250         Image *ima;
251         ImBuf *ibuf;
252         ImagePaintPartialRedraw *partRedrawRect;
253         void **undoRect; /* only used to build undo tiles after painting */
254         int touch;
255 } ProjPaintImage;
256
257 /* Main projection painting struct passed to all projection painting functions */
258 typedef struct ProjPaintState {
259         View3D *v3d;
260         RegionView3D *rv3d;
261         ARegion *ar;
262         Scene *scene;
263         int source; /* PROJ_SRC_**** */
264
265         Brush *brush;
266         short tool, blend;
267         Object *ob;
268         /* end similarities with ImagePaintState */
269         
270         DerivedMesh    *dm;
271         int dm_totface;
272         int dm_totvert;
273         int dm_release;
274
275         MVert          *dm_mvert;
276         MFace          *dm_mface;
277         MTFace         *dm_mtface;
278         MTFace         *dm_mtface_clone;    /* other UV map, use for cloning between layers */
279         MTFace         *dm_mtface_stencil;
280         
281         /* projection painting only */
282         MemArena *arena_mt[BLENDER_MAX_THREADS]; /* for multithreading, the first item is sometimes used for non threaded cases too */
283         LinkNode **bucketRect;              /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
284         LinkNode **bucketFaces;             /* bucketRect aligned array linkList of faces overlapping each bucket */
285         unsigned char *bucketFlags;         /* store if the bucks have been initialized  */
286 #ifndef PROJ_DEBUG_NOSEAMBLEED
287         char *faceSeamFlags;                /* store info about faces, if they are initialized etc*/
288         float (*faceSeamUVs)[4][2];         /* expanded UVs for faces to use as seams */
289         LinkNode **vertFaces;               /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
290 #endif
291         char *vertFlags;                    /* store options per vert, now only store if the vert is pointing away from the view */
292         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 */
293         int buckets_y;
294         
295         ProjPaintImage *projImages;
296         
297         int image_tot;              /* size of projectImages array */
298         
299         float (*screenCoords)[4];   /* verts projected into floating point screen space */
300         
301         float screenMin[2];         /* 2D bounds for mesh verts on the screen's plane (screenspace) */
302         float screenMax[2]; 
303         float screen_width;         /* Calculated from screenMin & screenMax */
304         float screen_height;
305         int winx, winy;             /* from the carea or from the projection render */
306         
307         /* options for projection painting */
308         int do_layer_clone;
309         int do_layer_stencil;
310         int do_layer_stencil_inv;
311         
312         short do_occlude;               /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
313         short do_backfacecull;          /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
314         short do_mask_normal;           /* mask out pixels based on their normals */
315         short do_new_shading_nodes;     /* cache BKE_scene_use_new_shading_nodes value */
316         float normal_angle;             /* what angle to mask at*/
317         float normal_angle_inner;
318         float normal_angle_range;       /* difference between normal_angle and normal_angle_inner, for easy access */
319         
320         short is_ortho;
321         short is_airbrush;              /* only to avoid using (ps.brush->flag & BRUSH_AIRBRUSH) */
322         short is_texbrush;              /* only to avoid running  */
323 #ifndef PROJ_DEBUG_NOSEAMBLEED
324         float seam_bleed_px;
325 #endif
326         /* clone vars */
327         float cloneOffset[2];
328         
329         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
330         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
331         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
332         float clipsta, clipend;
333         
334         /* reproject vars */
335         Image *reproject_image;
336         ImBuf *reproject_ibuf;
337
338
339         /* threads */
340         int thread_tot;
341         int bucketMin[2];
342         int bucketMax[2];
343         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
344 } ProjPaintState;
345
346 typedef union pixelPointer {
347         float *f_pt;            /* float buffer */
348         unsigned int *uint_pt; /* 2 ways to access a char buffer */
349         unsigned char *ch_pt;
350 } PixelPointer;
351
352 typedef union pixelStore {
353         unsigned char ch[4];
354         unsigned int uint;
355         float f[4];
356 } PixelStore;
357
358 typedef struct ProjPixel {
359         float projCoSS[2]; /* the floating point screen projection of this pixel */
360         
361         /* Only used when the airbrush is disabled.
362          * Store the max mask value to avoid painting over an area with a lower opacity
363          * with an advantage that we can avoid touching the pixel at all, if the 
364          * new mask value is lower then mask_max */
365         unsigned short mask_max;
366         
367         /* for various reasons we may want to mask out painting onto this pixel */
368         unsigned short mask;
369         
370         short x_px, y_px;
371         
372         PixelStore origColor;
373         PixelStore newColor;
374         PixelPointer pixel;
375         
376         short image_index; /* if anyone wants to paint onto more then 32768 images they can bite me */
377         unsigned char bb_cell_index;
378 } ProjPixel;
379
380 typedef struct ProjPixelClone {
381         struct ProjPixel __pp;
382         PixelStore clonepx;
383 } ProjPixelClone;
384
385 /* Finish projection painting structs */
386
387 typedef struct UndoImageTile {
388         struct UndoImageTile *next, *prev;
389
390         char idname[MAX_ID_NAME];  /* name instead of pointer*/
391         char ibufname[IB_FILENAME_SIZE];
392
393         union {
394                 float        *fp;
395                 unsigned int *uint;
396                 void         *pt;
397         } rect;
398         int x, y;
399
400         short source, use_float;
401         char gen_type;
402 } UndoImageTile;
403
404 static ImagePaintPartialRedraw imapaintpartial = {0, 0, 0, 0, 0};
405
406 /* UNDO */
407
408 static void undo_copy_tile(UndoImageTile *tile, ImBuf *tmpibuf, ImBuf *ibuf, int restore)
409 {
410         /* copy or swap contents of tile->rect and region in ibuf->rect */
411         IMB_rectcpy(tmpibuf, ibuf, 0, 0, tile->x * IMAPAINT_TILE_SIZE,
412                     tile->y * IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE);
413
414         if (ibuf->rect_float) {
415                 SWAP(float *, tmpibuf->rect_float, tile->rect.fp);
416         }
417         else {
418                 SWAP(unsigned int *, tmpibuf->rect, tile->rect.uint);
419         }
420         
421         if (restore)
422                 IMB_rectcpy(ibuf, tmpibuf, tile->x * IMAPAINT_TILE_SIZE,
423                             tile->y * IMAPAINT_TILE_SIZE, 0, 0, IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE);
424 }
425
426 static void *image_undo_push_tile(Image *ima, ImBuf *ibuf, ImBuf **tmpibuf, int x_tile, int y_tile)
427 {
428         ListBase *lb = undo_paint_push_get_list(UNDO_PAINT_IMAGE);
429         UndoImageTile *tile;
430         int allocsize;
431         short use_float = ibuf->rect_float ? 1 : 0;
432
433         for (tile = lb->first; tile; tile = tile->next)
434                 if (tile->x == x_tile && tile->y == y_tile && ima->gen_type == tile->gen_type && ima->source == tile->source)
435                         if (tile->use_float == use_float)
436                                 if (strcmp(tile->idname, ima->id.name) == 0 && strcmp(tile->ibufname, ibuf->name) == 0)
437                                         return tile->rect.pt;
438         
439         if (*tmpibuf == NULL)
440                 *tmpibuf = IMB_allocImBuf(IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, 32, IB_rectfloat | IB_rect);
441         
442         tile = MEM_callocN(sizeof(UndoImageTile), "UndoImageTile");
443         BLI_strncpy(tile->idname, ima->id.name, sizeof(tile->idname));
444         tile->x = x_tile;
445         tile->y = y_tile;
446
447         allocsize = IMAPAINT_TILE_SIZE * IMAPAINT_TILE_SIZE * 4;
448         allocsize *= (ibuf->rect_float) ? sizeof(float) : sizeof(char);
449         tile->rect.pt = MEM_mapallocN(allocsize, "UndeImageTile.rect");
450
451         BLI_strncpy(tile->ibufname, ibuf->name, sizeof(tile->ibufname));
452
453         tile->gen_type = ima->gen_type;
454         tile->source = ima->source;
455         tile->use_float = use_float;
456
457         undo_copy_tile(tile, *tmpibuf, ibuf, 0);
458         undo_paint_push_count_alloc(UNDO_PAINT_IMAGE, allocsize);
459
460         BLI_addtail(lb, tile);
461         
462         return tile->rect.pt;
463 }
464
465 static void image_undo_restore(bContext *C, ListBase *lb)
466 {
467         Main *bmain = CTX_data_main(C);
468         Image *ima = NULL;
469         ImBuf *ibuf, *tmpibuf;
470         UndoImageTile *tile;
471
472         tmpibuf = IMB_allocImBuf(IMAPAINT_TILE_SIZE, IMAPAINT_TILE_SIZE, 32,
473                                  IB_rectfloat | IB_rect);
474         
475         for (tile = lb->first; tile; tile = tile->next) {
476                 short use_float;
477
478                 /* find image based on name, pointer becomes invalid with global undo */
479                 if (ima && strcmp(tile->idname, ima->id.name) == 0) {
480                         /* ima is valid */
481                 }
482                 else {
483                         ima = BLI_findstring(&bmain->image, tile->idname, offsetof(ID, name));
484                 }
485
486                 ibuf = BKE_image_get_ibuf(ima, NULL);
487
488                 if (ima && ibuf && strcmp(tile->ibufname, ibuf->name) != 0) {
489                         /* current ImBuf filename was changed, probably current frame
490                          * was changed when paiting on image sequence, rather than storing
491                          * full image user (which isn't so obvious, btw) try to find ImBuf with
492                          * matched file name in list of already loaded images */
493
494                         ibuf = BLI_findstring(&ima->ibufs, tile->ibufname, offsetof(ImBuf, name));
495                 }
496
497                 if (!ima || !ibuf || !(ibuf->rect || ibuf->rect_float))
498                         continue;
499
500                 if (ima->gen_type != tile->gen_type || ima->source != tile->source)
501                         continue;
502
503                 use_float = ibuf->rect_float ? 1 : 0;
504
505                 if (use_float != tile->use_float)
506                         continue;
507
508                 undo_copy_tile(tile, tmpibuf, ibuf, 1);
509
510                 GPU_free_image(ima); /* force OpenGL reload */
511                 if (ibuf->rect_float)
512                         ibuf->userflags |= IB_RECT_INVALID; /* force recreate of char rect */
513                 if (ibuf->mipmap[0])
514                         ibuf->userflags |= IB_MIPMAP_INVALID;  /* force mipmap recreatiom */
515
516         }
517
518         IMB_freeImBuf(tmpibuf);
519 }
520
521 static void image_undo_free(ListBase *lb)
522 {
523         UndoImageTile *tile;
524
525         for (tile = lb->first; tile; tile = tile->next)
526                 MEM_freeN(tile->rect.pt);
527 }
528
529 /* get active image for face depending on old/new shading system */
530
531 static Image *imapaint_face_image(const ImagePaintState *s, int face_index)
532 {
533         Image *ima;
534
535         if (BKE_scene_use_new_shading_nodes(s->scene)) {
536                 MFace *mf = &s->dm_mface[face_index];
537                 ED_object_get_active_image(s->ob, mf->mat_nr + 1, &ima, NULL, NULL);
538         }
539         else {
540                 MTFace *tf = &s->dm_mtface[face_index];
541                 ima = tf->tpage;
542         }
543
544         return ima;
545 }
546
547 static Image *project_paint_face_image(const ProjPaintState *ps, MTFace *dm_mtface, int face_index)
548 {
549         Image *ima;
550
551         if (ps->do_new_shading_nodes) { /* cached BKE_scene_use_new_shading_nodes result */
552                 MFace *mf = ps->dm_mface + face_index;
553                 ED_object_get_active_image(ps->ob, mf->mat_nr + 1, &ima, NULL, NULL);
554         }
555         else {
556                 ima = dm_mtface[face_index].tpage;
557         }
558
559         return ima;
560 }
561
562 /* fast projection bucket array lookup, use the safe version for bound checking  */
563 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
564 {
565         /* If we were not dealing with screenspace 2D coords we could simple do...
566          * ps->bucketRect[x + (y*ps->buckets_y)] */
567         
568         /* please explain?
569          * projCoSS[0] - ps->screenMin[0]   : zero origin
570          * ... / ps->screen_width           : range from 0.0 to 1.0
571          * ... * ps->buckets_x              : use as a bucket index
572          *
573          * Second multiplication does similar but for vertical offset
574          */
575         return ( (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
576                (((int)(((projCoSS[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
577 }
578
579 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
580 {
581         int bucket_index = project_bucket_offset(ps, projCoSS);
582         
583         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
584                 return -1;
585         }
586         else {
587                 return bucket_index;
588         }
589 }
590
591 /* still use 2D X,Y space but this works for verts transformed by a perspective matrix, using their 4th component as a weight */
592 static void barycentric_weights_v2_persp(const float v1[4], const float v2[4], const float v3[4], const float co[2], float w[3])
593 {
594         float wtot_inv, wtot;
595
596         w[0] = area_tri_signed_v2(v2, v3, co) / v1[3];
597         w[1] = area_tri_signed_v2(v3, v1, co) / v2[3];
598         w[2] = area_tri_signed_v2(v1, v2, co) / v3[3];
599         wtot = w[0] + w[1] + w[2];
600
601         if (wtot != 0.0f) {
602                 wtot_inv = 1.0f / wtot;
603
604                 w[0] = w[0] * wtot_inv;
605                 w[1] = w[1] * wtot_inv;
606                 w[2] = w[2] * wtot_inv;
607         }
608         else /* dummy values for zero area face */
609                 w[0] = w[1] = w[2] = 1.0f / 3.0f;
610 }
611
612 static float VecZDepthOrtho(const float pt[2],
613                             const float v1[3], const float v2[3], const float v3[3],
614                             float w[3])
615 {
616         barycentric_weights_v2(v1, v2, v3, pt, w);
617         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
618 }
619
620 static float VecZDepthPersp(const float pt[2],
621                             const float v1[4], const float v2[4], const float v3[4],
622                             float w[3])
623 {
624         float wtot_inv, wtot;
625         float w_tmp[3];
626
627         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
628         /* for the depth we need the weights to match what
629          * barycentric_weights_v2 would return, in this case its easiest just to
630          * undo the 4th axis division and make it unit-sum
631          *
632          * don't call barycentric_weights_v2() becaue our callers expect 'w'
633          * to be weighted from the perspective */
634         w_tmp[0] = w[0] * v1[3];
635         w_tmp[1] = w[1] * v2[3];
636         w_tmp[2] = w[2] * v3[3];
637
638         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
639
640         if (wtot != 0.0f) {
641                 wtot_inv = 1.0f / wtot;
642
643                 w_tmp[0] = w_tmp[0] * wtot_inv;
644                 w_tmp[1] = w_tmp[1] * wtot_inv;
645                 w_tmp[2] = w_tmp[2] * wtot_inv;
646         }
647         else /* dummy values for zero area face */
648                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
649         /* done mimicing barycentric_weights_v2() */
650
651         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
652 }
653
654
655 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
656 static int project_paint_PickFace(const ProjPaintState *ps, float pt[2], float w[3], int *side)
657 {
658         LinkNode *node;
659         float w_tmp[3];
660         float *v1, *v2, *v3, *v4;
661         int bucket_index;
662         int face_index;
663         int best_side = -1;
664         int best_face_index = -1;
665         float z_depth_best = FLT_MAX, z_depth;
666         MFace *mf;
667         
668         bucket_index = project_bucket_offset_safe(ps, pt);
669         if (bucket_index == -1)
670                 return -1;
671         
672         
673         
674         /* we could return 0 for 1 face buckets, as long as this function assumes
675          * that the point its testing is only every originated from an existing face */
676         
677         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
678                 face_index = GET_INT_FROM_POINTER(node->link);
679                 mf = ps->dm_mface + face_index;
680                 
681                 v1 = ps->screenCoords[mf->v1];
682                 v2 = ps->screenCoords[mf->v2];
683                 v3 = ps->screenCoords[mf->v3];
684                 
685                 if (isect_point_tri_v2(pt, v1, v2, v3)) {
686                         if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v2, v3, w_tmp);
687                         else z_depth = VecZDepthPersp(pt, v1, v2, v3, w_tmp);
688                         
689                         if (z_depth < z_depth_best) {
690                                 best_face_index = face_index;
691                                 best_side = 0;
692                                 z_depth_best = z_depth;
693                                 copy_v3_v3(w, w_tmp);
694                         }
695                 }
696                 else if (mf->v4) {
697                         v4 = ps->screenCoords[mf->v4];
698                         
699                         if (isect_point_tri_v2(pt, v1, v3, v4)) {
700                                 if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v3, v4, w_tmp);
701                                 else z_depth = VecZDepthPersp(pt, v1, v3, v4, w_tmp);
702
703                                 if (z_depth < z_depth_best) {
704                                         best_face_index = face_index;
705                                         best_side = 1;
706                                         z_depth_best = z_depth;
707                                         copy_v3_v3(w, w_tmp);
708                                 }
709                         }
710                 }
711         }
712         
713         *side = best_side;
714         return best_face_index; /* will be -1 or a valid face */
715 }
716
717 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
718 static void uvco_to_wrapped_pxco(float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
719 {
720         /* use */
721         *x = (float)fmodf(uv[0], 1.0f);
722         *y = (float)fmodf(uv[1], 1.0f);
723         
724         if (*x < 0.0f) *x += 1.0f;
725         if (*y < 0.0f) *y += 1.0f;
726         
727         *x = *x * ibuf_x - 0.5f;
728         *y = *y * ibuf_y - 0.5f;
729 }
730
731 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
732 static int project_paint_PickColor(const ProjPaintState *ps, float pt[2], float *rgba_fp, unsigned char *rgba, const int interp)
733 {
734         float w[3], uv[2];
735         int side;
736         int face_index;
737         MTFace *tf;
738         Image *ima;
739         ImBuf *ibuf;
740         int xi, yi;
741         
742         
743         face_index = project_paint_PickFace(ps, pt, w, &side);
744         
745         if (face_index == -1)
746                 return 0;
747         
748         tf = ps->dm_mtface + face_index;
749         
750         if (side == 0) {
751                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[1], tf->uv[2], w);
752         }
753         else { /* QUAD */
754                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[2], tf->uv[3], w);
755         }
756
757         ima = project_paint_face_image(ps, ps->dm_mtface, face_index);
758         ibuf = ima->ibufs.first; /* we must have got the imbuf before getting here */
759         if (!ibuf) return 0;
760         
761         if (interp) {
762                 float x, y;
763                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
764                 
765                 if (ibuf->rect_float) {
766                         if (rgba_fp) {
767                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
768                         }
769                         else {
770                                 float rgba_tmp_f[4];
771                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
772                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(rgba, rgba_tmp_f);
773                         }
774                 }
775                 else {
776                         if (rgba) {
777                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
778                         }
779                         else {
780                                 unsigned char rgba_tmp[4];
781                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
782                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(rgba_fp, rgba_tmp);
783                         }
784                 }
785         }
786         else {
787                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
788                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
789                 //if (xi<0 || xi>=ibuf->x  ||  yi<0 || yi>=ibuf->y) return 0;
790                 
791                 /* wrap */
792                 xi = ((int)(uv[0] * ibuf->x)) % ibuf->x;
793                 if (xi < 0) xi += ibuf->x;
794                 yi = ((int)(uv[1] * ibuf->y)) % ibuf->y;
795                 if (yi < 0) yi += ibuf->y;
796                 
797                 
798                 if (rgba) {
799                         if (ibuf->rect_float) {
800                                 float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
801                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(rgba, rgba_tmp_fp);
802                         }
803                         else {
804                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
805                         }
806                 }
807                 
808                 if (rgba_fp) {
809                         if (ibuf->rect_float) {
810                                 copy_v4_v4(rgba_fp, (ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
811                         }
812                         else {
813                                 char *tmp_ch = ((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
814                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(rgba_fp, tmp_ch);
815                         }
816                 }
817         }
818         return 1;
819 }
820
821 /* Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusuion test)
822  * return...
823  *  0   : no occlusion
824  * -1   : no occlusion but 2D intersection is true (avoid testing the other half of a quad)
825  *  1   : occluded
826  *  2   : occluded with w[3] weights set (need to know in some cases) */
827
828 static int project_paint_occlude_ptv(float pt[3], float v1[4], float v2[4], float v3[4], float w[3], int is_ortho)
829 {
830         /* if all are behind us, return false */
831         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
832                 return 0;
833                 
834         /* do a 2D point in try intersection */
835         if (!isect_point_tri_v2(pt, v1, v2, v3))
836                 return 0;  /* we know there is  */
837         
838
839         /* From here on we know there IS an intersection */
840         /* if ALL of the verts are infront of us then we know it intersects ? */
841         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
842                 return 1;
843         }
844         else {
845                 /* we intersect? - find the exact depth at the point of intersection */
846                 /* Is this point is occluded by another face? */
847                 if (is_ortho) {
848                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
849                 }
850                 else {
851                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
852                 }
853         }
854         return -1;
855 }
856
857
858 static int project_paint_occlude_ptv_clip(const ProjPaintState *ps, const MFace *mf,
859                                           float pt[3], float v1[4], float v2[4], float v3[4],
860                                           const int side)
861 {
862         float w[3], wco[3];
863         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, ps->is_ortho);
864
865         if (ret <= 0)
866                 return ret;
867
868         if (ret == 1) { /* weights not calculated */
869                 if (ps->is_ortho) barycentric_weights_v2(v1, v2, v3, pt, w);
870                 else barycentric_weights_v2_persp(v1, v2, v3, pt, w);
871         }
872
873         /* Test if we're in the clipped area, */
874         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);
875         else interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
876         
877         if (!ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
878                 return 1;
879         }
880         
881         return -1;
882 }
883
884
885 /* Check if a screenspace location is occluded by any other faces
886  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
887  * and dosn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
888 static int project_bucket_point_occluded(const ProjPaintState *ps, LinkNode *bucketFace, const int orig_face, float pixelScreenCo[4])
889 {
890         MFace *mf;
891         int face_index;
892         int isect_ret;
893         float w[3]; /* not needed when clipping */
894         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
895         
896         /* we could return 0 for 1 face buckets, as long as this function assumes
897          * that the point its testing is only every originated from an existing face */
898
899         for (; bucketFace; bucketFace = bucketFace->next) {
900                 face_index = GET_INT_FROM_POINTER(bucketFace->link);
901
902                 if (orig_face != face_index) {
903                         mf = ps->dm_mface + face_index;
904                         if (do_clip)
905                                 isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], 0);
906                         else
907                                 isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], w, ps->is_ortho);
908
909                         /* Note, if isect_ret==-1 then we don't want to test the other side of the quad */
910                         if (isect_ret == 0 && mf->v4) {
911                                 if (do_clip)
912                                         isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], 1);
913                                 else
914                                         isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], w, ps->is_ortho);
915                         }
916                         if (isect_ret >= 1) {
917                                 /* TODO - we may want to cache the first hit,
918                                  * it is not possible to swap the face order in the list anymore */
919                                 return 1;
920                         }
921                 }
922         }
923         return 0;
924 }
925
926 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
927  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
928 #define ISECT_TRUE 1
929 #define ISECT_TRUE_P1 2
930 #define ISECT_TRUE_P2 3
931 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
932 {
933         float y_diff;
934         
935         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
936                 *x_isect = p1[0];
937                 return ISECT_TRUE_P1;
938         }
939         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
940                 *x_isect = p2[0];
941                 return ISECT_TRUE_P2;
942         }
943         
944         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
945         
946         if (y_diff < 0.000001f) {
947                 *x_isect = (p1[0] + p2[0]) * 0.5f;
948                 return ISECT_TRUE;              
949         }
950         
951         if (p1[1] > y_level && p2[1] < y_level) {
952                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /*(p1[1]-p2[1]);*/
953                 return ISECT_TRUE;
954         }
955         else if (p1[1] < y_level && p2[1] > y_level) {
956                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /*(p2[1]-p1[1]);*/
957                 return ISECT_TRUE;
958         }
959         else {
960                 return 0;
961         }
962 }
963
964 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
965 {
966         float x_diff;
967         
968         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
969                 *y_isect = p1[1];
970                 return ISECT_TRUE_P1;
971         }
972         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
973                 *y_isect = p2[1];
974                 return ISECT_TRUE_P2;
975         }
976         
977         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
978         
979         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
980                 *y_isect = (p1[0] + p2[0]) * 0.5f;
981                 return ISECT_TRUE;              
982         }
983         
984         if (p1[0] > x_level && p2[0] < x_level) {
985                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff; /*(p1[0]-p2[0]);*/
986                 return ISECT_TRUE;
987         }
988         else if (p1[0] < x_level && p2[0] > x_level) {
989                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff; /*(p2[0]-p1[0]);*/
990                 return ISECT_TRUE;
991         }
992         else {
993                 return 0;
994         }
995 }
996
997 /* simple func use for comparing UV locations to check if there are seams.
998  * Its possible this gives incorrect results, when the UVs for 1 face go into the next 
999  * tile, but do not do this for the adjacent face, it could return a false positive.
1000  * This is so unlikely that Id not worry about it. */
1001 #ifndef PROJ_DEBUG_NOSEAMBLEED
1002 static int cmp_uv(const float vec2a[2], const float vec2b[2])
1003 {
1004         /* if the UV's are not between 0.0 and 1.0 */
1005         float xa = (float)fmodf(vec2a[0], 1.0f);
1006         float ya = (float)fmodf(vec2a[1], 1.0f);
1007         
1008         float xb = (float)fmodf(vec2b[0], 1.0f);
1009         float yb = (float)fmodf(vec2b[1], 1.0f);        
1010         
1011         if (xa < 0.0f) xa += 1.0f;
1012         if (ya < 0.0f) ya += 1.0f;
1013         
1014         if (xb < 0.0f) xb += 1.0f;
1015         if (yb < 0.0f) yb += 1.0f;
1016         
1017         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
1018 }
1019 #endif
1020
1021 /* set min_px and max_px to the image space bounds of the UV coords 
1022  * return zero if there is no area in the returned rectangle */
1023 #ifndef PROJ_DEBUG_NOSEAMBLEED
1024 static int pixel_bounds_uv(
1025         const float uv1[2], const float uv2[2], const float uv3[2], const float uv4[2],
1026         rcti *bounds_px,
1027         const int ibuf_x, const int ibuf_y,
1028         int is_quad
1029         )
1030 {
1031         float min_uv[2], max_uv[2]; /* UV bounds */
1032         
1033         INIT_MINMAX2(min_uv, max_uv);
1034         
1035         DO_MINMAX2(uv1, min_uv, max_uv);
1036         DO_MINMAX2(uv2, min_uv, max_uv);
1037         DO_MINMAX2(uv3, min_uv, max_uv);
1038         if (is_quad)
1039                 DO_MINMAX2(uv4, min_uv, max_uv);
1040         
1041         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
1042         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
1043         
1044         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
1045         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
1046         
1047         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
1048         
1049         /* face uses no UV area when quantized to pixels? */
1050         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
1051 }
1052 #endif
1053
1054 static int pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
1055 {
1056         float min_uv[2], max_uv[2]; /* UV bounds */
1057         
1058         if (tot == 0) {
1059                 return 0;
1060         }
1061         
1062         INIT_MINMAX2(min_uv, max_uv);
1063         
1064         while (tot--) {
1065                 DO_MINMAX2((*uv), min_uv, max_uv);
1066                 uv++;
1067         }
1068         
1069         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
1070         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
1071         
1072         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
1073         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
1074         
1075         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
1076         
1077         /* face uses no UV area when quantized to pixels? */
1078         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
1079 }
1080
1081 #ifndef PROJ_DEBUG_NOSEAMBLEED
1082
1083 /* This function returns 1 if this face has a seam along the 2 face-vert indices
1084  * 'orig_i1_fidx' and 'orig_i2_fidx' */
1085 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)
1086 {
1087         LinkNode *node;
1088         int face_index;
1089         unsigned int i1, i2;
1090         int i1_fidx = -1, i2_fidx = -1; /* index in face */
1091         MFace *mf;
1092         MTFace *tf;
1093         const MFace *orig_mf = ps->dm_mface + orig_face;  
1094         const MTFace *orig_tf = ps->dm_mtface + orig_face;
1095         
1096         /* vert indices from face vert order indices */
1097         i1 = (*(&orig_mf->v1 + orig_i1_fidx));
1098         i2 = (*(&orig_mf->v1 + orig_i2_fidx));
1099         
1100         for (node = ps->vertFaces[i1]; node; node = node->next) {
1101                 face_index = GET_INT_FROM_POINTER(node->link);
1102
1103                 if (face_index != orig_face) {
1104                         mf = ps->dm_mface + face_index;
1105                         /* could check if the 2 faces images match here,
1106                          * but then there wouldn't be a way to return the opposite face's info */
1107                         
1108                         
1109                         /* We need to know the order of the verts in the adjacent face 
1110                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
1111                         if      (mf->v1 == i1) i1_fidx = 0;
1112                         else if (mf->v2 == i1) i1_fidx = 1;
1113                         else if (mf->v3 == i1) i1_fidx = 2;
1114                         else if (mf->v4 && mf->v4 == i1) i1_fidx = 3;
1115
1116                         if      (mf->v1 == i2) i2_fidx = 0;
1117                         else if (mf->v2 == i2) i2_fidx = 1;
1118                         else if (mf->v3 == i2) i2_fidx = 2;
1119                         else if (mf->v4 && mf->v4 == i2) i2_fidx = 3;
1120                         
1121                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
1122                         if (i2_fidx != -1) {
1123                                 Image *tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
1124                                 Image *orig_tpage = project_paint_face_image(ps, ps->dm_mtface, orig_face);
1125
1126                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
1127                                 tf = ps->dm_mtface + face_index;
1128                                 
1129                                 /* set up the other face */
1130                                 *other_face = face_index;
1131                                 *orig_fidx = (i1_fidx < i2_fidx) ? i1_fidx : i2_fidx;
1132                                 
1133                                 /* first test if they have the same image */
1134                                 if ((orig_tpage == tpage) &&
1135                                     cmp_uv(orig_tf->uv[orig_i1_fidx], tf->uv[i1_fidx]) &&
1136                                     cmp_uv(orig_tf->uv[orig_i2_fidx], tf->uv[i2_fidx]) )
1137                                 {
1138                                         // printf("SEAM (NONE)\n");
1139                                         return 0;
1140                                         
1141                                 }
1142                                 else {
1143                                         // printf("SEAM (UV GAP)\n");
1144                                         return 1;
1145                                 }
1146                         }
1147                 }
1148         }
1149         // printf("SEAM (NO FACE)\n");
1150         *other_face = -1;
1151         return 1;
1152 }
1153
1154 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
1155  * since the outset coords are a margin that keep an even distance from the original UV's,
1156  * note that the image aspect is taken into account */
1157 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)
1158 {
1159         float a1, a2, a3, a4 = 0.0f;
1160         float puv[4][2]; /* pixelspace uv's */
1161         float no1[2], no2[2], no3[2], no4[2]; /* normals */
1162         float dir1[2], dir2[2], dir3[2], dir4[2];
1163         float ibuf_inv[2];
1164
1165         ibuf_inv[0] = 1.0f / (float)ibuf_x;
1166         ibuf_inv[1] = 1.0f / (float)ibuf_y;
1167
1168         /* make UV's in pixel space so we can */
1169         puv[0][0] = orig_uv[0][0] * ibuf_x;
1170         puv[0][1] = orig_uv[0][1] * ibuf_y;
1171         
1172         puv[1][0] = orig_uv[1][0] * ibuf_x;
1173         puv[1][1] = orig_uv[1][1] * ibuf_y;
1174         
1175         puv[2][0] = orig_uv[2][0] * ibuf_x;
1176         puv[2][1] = orig_uv[2][1] * ibuf_y;
1177         
1178         if (is_quad) {
1179                 puv[3][0] = orig_uv[3][0] * ibuf_x;
1180                 puv[3][1] = orig_uv[3][1] * ibuf_y;
1181         }
1182         
1183         /* face edge directions */
1184         sub_v2_v2v2(dir1, puv[1], puv[0]);
1185         sub_v2_v2v2(dir2, puv[2], puv[1]);
1186         normalize_v2(dir1);
1187         normalize_v2(dir2);
1188         
1189         if (is_quad) {
1190                 sub_v2_v2v2(dir3, puv[3], puv[2]);
1191                 sub_v2_v2v2(dir4, puv[0], puv[3]);
1192                 normalize_v2(dir3);
1193                 normalize_v2(dir4);
1194         }
1195         else {
1196                 sub_v2_v2v2(dir3, puv[0], puv[2]);
1197                 normalize_v2(dir3);
1198         }
1199
1200         /* TODO - angle_normalized_v2v2(...) * (M_PI/180.0f)
1201          * This is incorrect. Its already given radians but without it wont work.
1202          * need to look into a fix - campbell */
1203         if (is_quad) {
1204                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir4, dir1) * ((float)M_PI / 180.0f));
1205                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI / 180.0f));
1206                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI / 180.0f));
1207                 a4 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir4) * ((float)M_PI / 180.0f));
1208         }
1209         else {
1210                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir1) * ((float)M_PI / 180.0f));
1211                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI / 180.0f));
1212                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI / 180.0f));
1213         }
1214         
1215         if (is_quad) {
1216                 sub_v2_v2v2(no1, dir4, dir1);
1217                 sub_v2_v2v2(no2, dir1, dir2);
1218                 sub_v2_v2v2(no3, dir2, dir3);
1219                 sub_v2_v2v2(no4, dir3, dir4);
1220                 normalize_v2(no1);
1221                 normalize_v2(no2);
1222                 normalize_v2(no3);
1223                 normalize_v2(no4);
1224                 mul_v2_fl(no1, a1 * scaler);
1225                 mul_v2_fl(no2, a2 * scaler);
1226                 mul_v2_fl(no3, a3 * scaler);
1227                 mul_v2_fl(no4, a4 * scaler);
1228                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1229                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1230                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1231                 add_v2_v2v2(outset_uv[3], puv[3], no4);
1232                 mul_v2_v2(outset_uv[0], ibuf_inv);
1233                 mul_v2_v2(outset_uv[1], ibuf_inv);
1234                 mul_v2_v2(outset_uv[2], ibuf_inv);
1235                 mul_v2_v2(outset_uv[3], ibuf_inv);
1236         }
1237         else {
1238                 sub_v2_v2v2(no1, dir3, dir1);
1239                 sub_v2_v2v2(no2, dir1, dir2);
1240                 sub_v2_v2v2(no3, dir2, dir3);
1241                 normalize_v2(no1);
1242                 normalize_v2(no2);
1243                 normalize_v2(no3);
1244                 mul_v2_fl(no1, a1 * scaler);
1245                 mul_v2_fl(no2, a2 * scaler);
1246                 mul_v2_fl(no3, a3 * scaler);
1247                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1248                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1249                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1250
1251                 mul_v2_v2(outset_uv[0], ibuf_inv);
1252                 mul_v2_v2(outset_uv[1], ibuf_inv);
1253                 mul_v2_v2(outset_uv[2], ibuf_inv);
1254         }
1255 }
1256
1257 /* 
1258  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1259  * 1<<i - where i is (0-3) 
1260  * 
1261  * If we're multithreadng, make sure threads are locked when this is called
1262  */
1263 static void project_face_seams_init(const ProjPaintState *ps, const int face_index, const int is_quad)
1264 {
1265         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1266         int fidx1 = is_quad ? 3 : 2;
1267         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 */
1268         
1269         do {
1270                 if ((ps->faceSeamFlags[face_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1271                         if (check_seam(ps, face_index, fidx1, fidx2, &other_face, &other_fidx)) {
1272                                 ps->faceSeamFlags[face_index] |= 1 << fidx1;
1273                                 if (other_face != -1)
1274                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1275                         }
1276                         else {
1277                                 ps->faceSeamFlags[face_index] |= 16 << fidx1;
1278                                 if (other_face != -1)
1279                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1280                         }
1281                 }
1282                 
1283                 fidx2 = fidx1;
1284         } while (fidx1--);
1285 }
1286 #endif // PROJ_DEBUG_NOSEAMBLEED
1287
1288
1289 /* Converts a UV location to a 3D screenspace location
1290  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1291  * 
1292  * This is used for finding a pixels location in screenspace for painting */
1293 static void screen_px_from_ortho(
1294         float uv[2],
1295         float v1co[3], float v2co[3], float v3co[3],  /* Screenspace coords */
1296         float uv1co[2], float uv2co[2], float uv3co[2],
1297         float pixelScreenCo[4],
1298         float w[3])
1299 {
1300         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1301         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1302 }
1303
1304 /* same as screen_px_from_ortho except we need to take into account
1305  * the perspective W coord for each vert */
1306 static void screen_px_from_persp(
1307         float uv[2],
1308         float v1co[4], float v2co[4], float v3co[4],  /* screenspace coords */
1309         float uv1co[2], float uv2co[2], float uv3co[2],
1310         float pixelScreenCo[4],
1311         float w[3])
1312 {
1313
1314         float wtot_inv, wtot;
1315         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1316         
1317         /* re-weight from the 4th coord of each screen vert */
1318         w[0] *= v1co[3];
1319         w[1] *= v2co[3];
1320         w[2] *= v3co[3];
1321         
1322         wtot = w[0] + w[1] + w[2];
1323         
1324         if (wtot > 0.0f) {
1325                 wtot_inv = 1.0f / wtot;
1326                 w[0] *= wtot_inv;
1327                 w[1] *= wtot_inv;
1328                 w[2] *= wtot_inv;
1329         }
1330         else {
1331                 w[0] = w[1] = w[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1332         }
1333         /* done re-weighting */
1334         
1335         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1336 }
1337
1338 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])
1339 {
1340         float *uvCo1, *uvCo2, *uvCo3;
1341         float uv_other[2], x, y;
1342         
1343         uvCo1 =  (float *)tf_other->uv[0];
1344         if (side == 1) {
1345                 uvCo2 =  (float *)tf_other->uv[2];
1346                 uvCo3 =  (float *)tf_other->uv[3];
1347         }
1348         else {
1349                 uvCo2 =  (float *)tf_other->uv[1];
1350                 uvCo3 =  (float *)tf_other->uv[2];
1351         }
1352         
1353         interp_v2_v2v2v2(uv_other, uvCo1, uvCo2, uvCo3, (float *)w);
1354         
1355         /* use */
1356         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1357         
1358         
1359         if (ibuf_other->rect_float) { /* from float to float */
1360                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1361         }
1362         else { /* from char to float */
1363                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1364         }
1365                 
1366 }
1367
1368 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1369 static float project_paint_uvpixel_mask(
1370         const ProjPaintState *ps,
1371         const int face_index,
1372         const int side,
1373         const float w[3])
1374 {
1375         float mask;
1376         
1377         /* Image Mask */
1378         if (ps->do_layer_stencil) {
1379                 /* another UV maps image is masking this one's */
1380                 ImBuf *ibuf_other;
1381                 Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_stencil, face_index);
1382                 const MTFace *tf_other = ps->dm_mtface_stencil + face_index;
1383                 
1384                 if (other_tpage && (ibuf_other = BKE_image_get_ibuf(other_tpage, NULL))) {
1385                         /* BKE_image_get_ibuf - TODO - this may be slow */
1386                         unsigned char rgba_ub[4];
1387                         float rgba_f[4];
1388                         
1389                         project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, rgba_f);
1390                         
1391                         if (ibuf_other->rect_float) { /* from float to float */
1392                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) / 3.0f) * rgba_f[3];
1393                         }
1394                         else { /* from char to float */
1395                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) / (256 * 3.0f)) * (rgba_ub[3] / 256.0f);
1396                         }
1397                         
1398                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1399                                 mask = (1.0f - mask);
1400
1401                         if (mask == 0.0f) {
1402                                 return 0.0f;
1403                         }
1404                 }
1405                 else {
1406                         return 0.0f;
1407                 }
1408         }
1409         else {
1410                 mask = 1.0f;
1411         }
1412         
1413         /* calculate mask */
1414         if (ps->do_mask_normal) {
1415                 MFace *mf = ps->dm_mface + face_index;
1416                 short *no1, *no2, *no3;
1417                 float no[3], angle;
1418                 no1 = ps->dm_mvert[mf->v1].no;
1419                 if (side == 1) {
1420                         no2 = ps->dm_mvert[mf->v3].no;
1421                         no3 = ps->dm_mvert[mf->v4].no;
1422                 }
1423                 else {
1424                         no2 = ps->dm_mvert[mf->v2].no;
1425                         no3 = ps->dm_mvert[mf->v3].no;
1426                 }
1427                 
1428                 no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1429                 no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1430                 no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1431                 normalize_v3(no);
1432                 
1433                 /* now we can use the normal as a mask */
1434                 if (ps->is_ortho) {
1435                         angle = angle_normalized_v3v3((float *)ps->viewDir, no);
1436                 }
1437                 else {
1438                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1439                         float viewDirPersp[3];
1440                         float *co1, *co2, *co3;
1441                         co1 = ps->dm_mvert[mf->v1].co;
1442                         if (side == 1) {
1443                                 co2 = ps->dm_mvert[mf->v3].co;
1444                                 co3 = ps->dm_mvert[mf->v4].co;
1445                         }
1446                         else {
1447                                 co2 = ps->dm_mvert[mf->v2].co;
1448                                 co3 = ps->dm_mvert[mf->v3].co;
1449                         }
1450
1451                         /* Get the direction from the viewPoint to the pixel and normalize */
1452                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1453                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1454                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1455                         normalize_v3(viewDirPersp);
1456                         
1457                         angle = angle_normalized_v3v3(viewDirPersp, no);
1458                 }
1459                 
1460                 if (angle >= ps->normal_angle) {
1461                         return 0.0f; /* outsize the normal limit*/
1462                 }
1463                 else if (angle > ps->normal_angle_inner) {
1464                         mask *= (ps->normal_angle - angle) / ps->normal_angle_range;
1465                 } /* otherwise no mask normal is needed, were within the limit */
1466         }
1467         
1468         /* This only works when the opacity dosnt change while painting, stylus pressure messes with this
1469          * so don't use it. */
1470         // if (ps->is_airbrush == 0) mask *= BKE_brush_alpha_get(ps->brush);
1471         
1472         return mask;
1473 }
1474
1475 /* run this function when we know a bucket's, face's pixel can be initialized,
1476  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1477 static ProjPixel *project_paint_uvpixel_init(
1478         const ProjPaintState *ps,
1479         MemArena *arena,
1480         const ImBuf *ibuf,
1481         short x_px, short y_px,
1482         const float mask,
1483         const int face_index,
1484         const int image_index,
1485         const float pixelScreenCo[4],
1486         const int side,
1487         const float w[3])
1488 {
1489         ProjPixel *projPixel;
1490         short size;
1491         
1492         /* wrap pixel location */
1493         x_px = x_px % ibuf->x;
1494         if (x_px < 0) x_px += ibuf->x;
1495         y_px = y_px % ibuf->y;
1496         if (y_px < 0) y_px += ibuf->y;
1497         
1498         if (ps->tool == PAINT_TOOL_CLONE) {
1499                 size = sizeof(ProjPixelClone);
1500         }
1501         else if (ps->tool == PAINT_TOOL_SMEAR) {
1502                 size = sizeof(ProjPixelClone);
1503         }
1504         else {
1505                 size = sizeof(ProjPixel);
1506         }
1507         
1508         projPixel = (ProjPixel *)BLI_memarena_alloc(arena, size);
1509         //memset(projPixel, 0, size);
1510         
1511         if (ibuf->rect_float) {
1512                 projPixel->pixel.f_pt = ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1513                 projPixel->origColor.f[0] = projPixel->newColor.f[0] = projPixel->pixel.f_pt[0];  
1514                 projPixel->origColor.f[1] = projPixel->newColor.f[1] = projPixel->pixel.f_pt[1];  
1515                 projPixel->origColor.f[2] = projPixel->newColor.f[2] = projPixel->pixel.f_pt[2];  
1516                 projPixel->origColor.f[3] = projPixel->newColor.f[3] = projPixel->pixel.f_pt[3];  
1517         }
1518         else {
1519                 projPixel->pixel.ch_pt = ((unsigned char *)ibuf->rect + ((x_px + y_px * ibuf->x) * 4));
1520                 projPixel->origColor.uint = projPixel->newColor.uint = *projPixel->pixel.uint_pt;
1521         }
1522         
1523         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1524         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1525         
1526         projPixel->x_px = x_px;
1527         projPixel->y_px = y_px;
1528         
1529         projPixel->mask = (unsigned short)(mask * 65535);
1530         projPixel->mask_max = 0;
1531         
1532         /* which bounding box cell are we in?, needed for undo */
1533         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1534                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1535         
1536         /* done with view3d_project_float inline */
1537         if (ps->tool == PAINT_TOOL_CLONE) {
1538                 if (ps->dm_mtface_clone) {
1539                         ImBuf *ibuf_other;
1540                         Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_clone, face_index);
1541                         const MTFace *tf_other = ps->dm_mtface_clone + face_index;
1542                         
1543                         if (other_tpage && (ibuf_other = BKE_image_get_ibuf(other_tpage, NULL))) {
1544                                 /* BKE_image_get_ibuf - TODO - this may be slow */
1545                                 
1546                                 if (ibuf->rect_float) {
1547                                         if (ibuf_other->rect_float) { /* from float to float */
1548                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1549                                         }
1550                                         else { /* from char to float */
1551                                                 unsigned char rgba_ub[4];
1552                                                 project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, NULL);
1553                                                 IMAPAINT_CHAR_RGBA_TO_FLOAT(((ProjPixelClone *)projPixel)->clonepx.f, rgba_ub);
1554                                         }
1555                                 }
1556                                 else {
1557                                         if (ibuf_other->rect_float) { /* float to char */
1558                                                 float rgba[4];
1559                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, rgba);
1560                                                 IMAPAINT_FLOAT_RGBA_TO_CHAR(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1561                                         }
1562                                         else { /* char to char */
1563                                                 project_face_pixel(tf_other, ibuf_other, w, side, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1564                                         }
1565                                 }
1566                         }
1567                         else {
1568                                 if (ibuf->rect_float) {
1569                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1570                                 }
1571                                 else {
1572                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1573                                 }
1574                         }
1575                         
1576                 }
1577                 else {
1578                         float co[2];
1579                         sub_v2_v2v2(co, projPixel->projCoSS, (float *)ps->cloneOffset);
1580                         
1581                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1582                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1583                         if (ibuf->rect_float) {
1584                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1585                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1586                                 }
1587                         }
1588                         else {
1589                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1590                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1591                                 }
1592                         }
1593                 }
1594         }
1595         
1596 #ifdef PROJ_DEBUG_PAINT
1597         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1598         else                  projPixel->pixel.ch_pt[0] = 0;
1599 #endif
1600         projPixel->image_index = image_index;
1601         
1602         return projPixel;
1603 }
1604
1605 static int line_clip_rect2f(
1606         rctf *rect,
1607         const float l1[2], const float l2[2],
1608         float l1_clip[2], float l2_clip[2])
1609 {
1610         /* first account for horizontal, then vertical lines */
1611         /* horiz */
1612         if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) {
1613                 /* is the line out of range on its Y axis? */
1614                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1615                         return 0;
1616                 }
1617                 /* line is out of range on its X axis */
1618                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1619                         return 0;
1620                 }
1621                 
1622                 
1623                 if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1624                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1625                                 copy_v2_v2(l1_clip, l1);
1626                                 copy_v2_v2(l2_clip, l2);
1627                                 return 1;
1628                         }
1629                         else {
1630                                 return 0;
1631                         }
1632                 }
1633                 
1634                 copy_v2_v2(l1_clip, l1);
1635                 copy_v2_v2(l2_clip, l2);
1636                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1637                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1638                 return 1;
1639         }
1640         else if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) {
1641                 /* is the line out of range on its X axis? */
1642                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1643                         return 0;
1644                 }
1645                 
1646                 /* line is out of range on its Y axis */
1647                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1648                         return 0;
1649                 }
1650                 
1651                 if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1652                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1653                                 copy_v2_v2(l1_clip, l1);
1654                                 copy_v2_v2(l2_clip, l2);
1655                                 return 1;
1656                         }
1657                         else {
1658                                 return 0;
1659                         }
1660                 }
1661                 
1662                 copy_v2_v2(l1_clip, l1);
1663                 copy_v2_v2(l2_clip, l2);
1664                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1665                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1666                 return 1;
1667         }
1668         else {
1669                 float isect;
1670                 short ok1 = 0;
1671                 short ok2 = 0;
1672                 
1673                 /* Done with vertical lines */
1674                 
1675                 /* are either of the points inside the rectangle ? */
1676                 if (BLI_rctf_isect_pt_v(rect, l1)) {
1677                         copy_v2_v2(l1_clip, l1);
1678                         ok1 = 1;
1679                 }
1680                 
1681                 if (BLI_rctf_isect_pt_v(rect, l2)) {
1682                         copy_v2_v2(l2_clip, l2);
1683                         ok2 = 1;
1684                 }
1685                 
1686                 /* line inside rect */
1687                 if (ok1 && ok2) return 1;
1688                 
1689                 /* top/bottom */
1690                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1691                         if (l1[1] < l2[1]) { /* line 1 is outside */
1692                                 l1_clip[0] = isect;
1693                                 l1_clip[1] = rect->ymin;
1694                                 ok1 = 1;
1695                         }
1696                         else {
1697                                 l2_clip[0] = isect;
1698                                 l2_clip[1] = rect->ymin;
1699                                 ok2 = 2;
1700                         }
1701                 }
1702                 
1703                 if (ok1 && ok2) return 1;
1704                 
1705                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1706                         if (l1[1] > l2[1]) { /* line 1 is outside */
1707                                 l1_clip[0] = isect;
1708                                 l1_clip[1] = rect->ymax;
1709                                 ok1 = 1;
1710                         }
1711                         else {
1712                                 l2_clip[0] = isect;
1713                                 l2_clip[1] = rect->ymax;
1714                                 ok2 = 2;
1715                         }
1716                 }
1717                 
1718                 if (ok1 && ok2) return 1;
1719                 
1720                 /* left/right */
1721                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1722                         if (l1[0] < l2[0]) { /* line 1 is outside */
1723                                 l1_clip[0] = rect->xmin;
1724                                 l1_clip[1] = isect;
1725                                 ok1 = 1;
1726                         }
1727                         else {
1728                                 l2_clip[0] = rect->xmin;
1729                                 l2_clip[1] = isect;
1730                                 ok2 = 2;
1731                         }
1732                 }
1733         
1734                 if (ok1 && ok2) return 1;
1735                 
1736                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1737                         if (l1[0] > l2[0]) { /* line 1 is outside */
1738                                 l1_clip[0] = rect->xmax;
1739                                 l1_clip[1] = isect;
1740                                 ok1 = 1;
1741                         }
1742                         else {
1743                                 l2_clip[0] = rect->xmax;
1744                                 l2_clip[1] = isect;
1745                                 ok2 = 2;
1746                         }
1747                 }
1748                 
1749                 if (ok1 && ok2) {
1750                         return 1;
1751                 }
1752                 else {
1753                         return 0;
1754                 }
1755         }
1756 }
1757
1758
1759
1760 /* scale the quad & tri about its center
1761  * scaling by PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1762  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces */
1763 #ifndef PROJ_DEBUG_NOSEAMBLEED
1764 static void scale_quad(float insetCos[4][3], float *origCos[4], const float inset)
1765 {
1766         float cent[3];
1767         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0] + origCos[3][0]) / 4.0f;
1768         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1] + origCos[3][1]) / 4.0f;
1769         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2] + origCos[3][2]) / 4.0f;
1770         
1771         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1772         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1773         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1774         sub_v3_v3v3(insetCos[3], origCos[3], cent);
1775         
1776         mul_v3_fl(insetCos[0], inset);
1777         mul_v3_fl(insetCos[1], inset);
1778         mul_v3_fl(insetCos[2], inset);
1779         mul_v3_fl(insetCos[3], inset);
1780         
1781         add_v3_v3(insetCos[0], cent);
1782         add_v3_v3(insetCos[1], cent);
1783         add_v3_v3(insetCos[2], cent);
1784         add_v3_v3(insetCos[3], cent);
1785 }
1786
1787
1788 static void scale_tri(float insetCos[4][3], float *origCos[4], const float inset)
1789 {
1790         float cent[3];
1791         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) / 3.0f;
1792         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) / 3.0f;
1793         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) / 3.0f;
1794         
1795         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1796         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1797         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1798         
1799         mul_v3_fl(insetCos[0], inset);
1800         mul_v3_fl(insetCos[1], inset);
1801         mul_v3_fl(insetCos[2], inset);
1802         
1803         add_v3_v3(insetCos[0], cent);
1804         add_v3_v3(insetCos[1], cent);
1805         add_v3_v3(insetCos[2], cent);
1806 }
1807 #endif //PROJ_DEBUG_NOSEAMBLEED
1808
1809 static float len_squared_v2v2_alt(const float *v1, const float v2_1, const float v2_2)
1810 {
1811         float x, y;
1812
1813         x = v1[0] - v2_1;
1814         y = v1[1] - v2_2;
1815         return x * x + y * y;
1816 }
1817
1818 /* note, use a squared value so we can use len_squared_v2v2
1819  * be sure that you have done a bounds check first or this may fail */
1820 /* only give bucket_bounds as an arg because we need it elsewhere */
1821 static int project_bucket_isect_circle(const float cent[2], const float radius_squared, rctf *bucket_bounds)
1822 {
1823          
1824         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect 
1825          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1826          * this is even less work then an intersection test
1827          */
1828 #if 0
1829         if (BLI_rctf_isect_pt_v(bucket_bounds, cent))
1830                 return 1;
1831 #endif
1832         
1833         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1834             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1835         {
1836                 return 1;
1837         }
1838         
1839         /* out of bounds left */
1840         if (cent[0] < bucket_bounds->xmin) {
1841                 /* lower left out of radius test */
1842                 if (cent[1] < bucket_bounds->ymin) {
1843                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1844                 } 
1845                 /* top left test */
1846                 else if (cent[1] > bucket_bounds->ymax) {
1847                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1848                 }
1849         }
1850         else if (cent[0] > bucket_bounds->xmax) {
1851                 /* lower right out of radius test */
1852                 if (cent[1] < bucket_bounds->ymin) {
1853                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1854                 } 
1855                 /* top right test */
1856                 else if (cent[1] > bucket_bounds->ymax) {
1857                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1858                 }
1859         }
1860         
1861         return 0;
1862 }
1863
1864
1865
1866 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1867  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1868  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1869  * (viewed from the side)
1870  * 
1871  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1872  * funcs that only account for points inside the triangle.
1873  * however switching back to this for ortho is always an option */
1874
1875 static void rect_to_uvspace_ortho(
1876         rctf *bucket_bounds,
1877         float *v1coSS, float *v2coSS, float *v3coSS,
1878         float *uv1co, float *uv2co, float *uv3co,
1879         float bucket_bounds_uv[4][2],
1880         const int flip)
1881 {
1882         float uv[2];
1883         float w[3];
1884         
1885         /* get the UV space bounding box */
1886         uv[0] = bucket_bounds->xmax;
1887         uv[1] = bucket_bounds->ymin;
1888         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1889         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1890
1891         //uv[0] = bucket_bounds->xmax; // set above
1892         uv[1] = bucket_bounds->ymax;
1893         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1894         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1895
1896         uv[0] = bucket_bounds->xmin;
1897         //uv[1] = bucket_bounds->ymax; // set above
1898         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1899         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1900
1901         //uv[0] = bucket_bounds->xmin; // set above
1902         uv[1] = bucket_bounds->ymin;
1903         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1904         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1905 }
1906
1907 /* same as above but use barycentric_weights_v2_persp */
1908 static void rect_to_uvspace_persp(
1909         rctf *bucket_bounds,
1910         float *v1coSS, float *v2coSS, float *v3coSS,
1911         float *uv1co, float *uv2co, float *uv3co,
1912         float bucket_bounds_uv[4][2],
1913         const int flip
1914         )
1915 {
1916         float uv[2];
1917         float w[3];
1918         
1919         /* get the UV space bounding box */
1920         uv[0] = bucket_bounds->xmax;
1921         uv[1] = bucket_bounds->ymin;
1922         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1923         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1924
1925         //uv[0] = bucket_bounds->xmax; // set above
1926         uv[1] = bucket_bounds->ymax;
1927         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1928         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1929
1930         uv[0] = bucket_bounds->xmin;
1931         //uv[1] = bucket_bounds->ymax; // set above
1932         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1933         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1934
1935         //uv[0] = bucket_bounds->xmin; // set above
1936         uv[1] = bucket_bounds->ymin;
1937         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1938         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1939 }
1940
1941 /* This works as we need it to but we can save a few steps and not use it */
1942
1943 #if 0
1944 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
1945 {
1946         float v1[2], v2[2];
1947         
1948         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
1949         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
1950         
1951         return -atan2(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
1952 }
1953 #endif
1954
1955 #define ISECT_1 (1)
1956 #define ISECT_2 (1 << 1)
1957 #define ISECT_3 (1 << 2)
1958 #define ISECT_4 (1 << 3)
1959 #define ISECT_ALL3 ((1 << 3) - 1)
1960 #define ISECT_ALL4 ((1 << 4) - 1)
1961
1962 /* limit must be a fraction over 1.0f */
1963 static int IsectPT2Df_limit(float pt[2], float v1[2], float v2[2], float v3[2], float limit)
1964 {
1965         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;
1966 }
1967
1968 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
1969  * so we have the clipped UV's to do pixel intersection tests with 
1970  * */
1971 static int float_z_sort_flip(const void *p1, const void *p2)
1972 {
1973         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
1974 }
1975
1976 static int float_z_sort(const void *p1, const void *p2)
1977 {
1978         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
1979 }
1980
1981 static void project_bucket_clip_face(
1982         const int is_ortho,
1983         rctf *bucket_bounds,
1984         float *v1coSS, float *v2coSS, float *v3coSS,
1985         float *uv1co, float *uv2co, float *uv3co,
1986         float bucket_bounds_uv[8][2],
1987         int *tot)
1988 {
1989         int inside_bucket_flag = 0;
1990         int inside_face_flag = 0;
1991         const int flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
1992         
1993         float bucket_bounds_ss[4][2];
1994
1995         /* get the UV space bounding box */
1996         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v1coSS);
1997         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v2coSS) << 1;
1998         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v3coSS) << 2;
1999         
2000         if (inside_bucket_flag == ISECT_ALL3) {
2001                 /* all screenspace points are inside the bucket bounding box, this means we don't need to clip and can simply return the UVs */
2002                 if (flip) { /* facing the back? */
2003                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
2004                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2005                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
2006                 }
2007                 else {
2008                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
2009                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2010                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
2011                 }
2012                 
2013                 *tot = 3; 
2014                 return;
2015         }
2016         
2017         /* get the UV space bounding box */
2018         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
2019         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
2020         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
2021         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
2022         
2023         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
2024         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
2025         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
2026
2027         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
2028         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
2029         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
2030
2031         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
2032         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
2033         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
2034         
2035         if (inside_face_flag == ISECT_ALL4) {
2036                 /* bucket is totally inside the screenspace face, we can safely use weights */
2037                 
2038                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2039                 else rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2040                 
2041                 *tot = 4;
2042                 return;
2043         }
2044         else {
2045                 /* The Complicated Case! 
2046                  * 
2047                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
2048                  * 
2049                  * we need to make a convex polyline from the intersection between the screenspace face
2050                  * and the bucket bounds.
2051                  * 
2052                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
2053                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
2054                  * do a correct clipping on both shapes. */
2055                 
2056                 
2057                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
2058                 
2059                 
2060                 
2061                 /* Maximum possible 6 intersections when using a rectangle and triangle */
2062                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
2063                 float v1_clipSS[2], v2_clipSS[2];
2064                 float w[3];
2065                 
2066                 /* calc center */
2067                 float cent[2] = {0.0f, 0.0f};
2068                 /*float up[2] = {0.0f, 1.0f};*/
2069                 int i;
2070                 short doubles;
2071                 
2072                 (*tot) = 0;
2073                 
2074                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
2075                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
2076                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
2077                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
2078
2079                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
2080                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
2081                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
2082                 
2083                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
2084                         if (line_clip_rect2f(bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
2085                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2086                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2087                         }
2088                 }
2089                 
2090                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
2091                         if (line_clip_rect2f(bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
2092                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2093                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2094                         }
2095                 }       
2096                 
2097                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
2098                         if (line_clip_rect2f(bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
2099                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2100                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2101                         }
2102                 }
2103                 
2104                 
2105                 if ((*tot) < 3) { /* no intersections to speak of */
2106                         *tot = 0;
2107                         return;
2108                 }
2109         
2110                 /* now we have all points we need, collect their angles and sort them clockwise */
2111                 
2112                 for (i = 0; i < (*tot); i++) {
2113                         cent[0] += isectVCosSS[i][0];
2114                         cent[1] += isectVCosSS[i][1];
2115                 }
2116                 cent[0] = cent[0] / (float)(*tot);
2117                 cent[1] = cent[1] / (float)(*tot);
2118                 
2119                 
2120                 
2121                 /* Collect angles for every point around the center point */
2122
2123                 
2124 #if 0   /* uses a few more cycles then the above loop */
2125                 for (i = 0; i < (*tot); i++) {
2126                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
2127                 }
2128 #endif
2129
2130                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
2131                 v1_clipSS[1] = cent[1] + 1.0f;
2132                 
2133                 for (i = 0; i < (*tot); i++) {
2134                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2135                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2136                         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]);
2137                 }
2138                 
2139                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
2140                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
2141                 
2142                 /* remove doubles */
2143                 /* first/last check */
2144                 if (fabsf(isectVCosSS[0][0] - isectVCosSS[(*tot) - 1][0]) < PROJ_GEOM_TOLERANCE &&
2145                     fabsf(isectVCosSS[0][1] - isectVCosSS[(*tot) - 1][1]) < PROJ_GEOM_TOLERANCE)
2146                 {
2147                         (*tot)--;
2148                 }
2149                 
2150                 /* its possible there is only a few left after remove doubles */
2151                 if ((*tot) < 3) {
2152                         // printf("removed too many doubles A\n");
2153                         *tot = 0;
2154                         return;
2155                 }
2156                 
2157                 doubles = TRUE;
2158                 while (doubles == TRUE) {
2159                         doubles = FALSE;
2160                         for (i = 1; i < (*tot); i++) {
2161                                 if (fabsf(isectVCosSS[i - 1][0] - isectVCosSS[i][0]) < PROJ_GEOM_TOLERANCE &&
2162                                     fabsf(isectVCosSS[i - 1][1] - isectVCosSS[i][1]) < PROJ_GEOM_TOLERANCE)
2163                                 {
2164                                         int j;
2165                                         for (j = i + 1; j < (*tot); j++) {
2166                                                 isectVCosSS[j - 1][0] = isectVCosSS[j][0];
2167                                                 isectVCosSS[j - 1][1] = isectVCosSS[j][1];
2168                                         }
2169                                         doubles = TRUE; /* keep looking for more doubles */
2170                                         (*tot)--;
2171                                 }
2172                         }
2173                 }
2174                 
2175                 /* its possible there is only a few left after remove doubles */
2176                 if ((*tot) < 3) {
2177                         // printf("removed too many doubles B\n");
2178                         *tot = 0;
2179                         return;
2180                 }
2181                 
2182                 
2183                 if (is_ortho) {
2184                         for (i = 0; i < (*tot); i++) {
2185                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2186                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2187                         }
2188                 }
2189                 else {
2190                         for (i = 0; i < (*tot); i++) {
2191                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2192                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2193                         }
2194                 }
2195         }
2196
2197 #ifdef PROJ_DEBUG_PRINT_CLIP
2198         /* include this at the bottom of the above function to debug the output */
2199
2200         {
2201                 /* If there are ever any problems, */
2202                 float test_uv[4][2];
2203                 int i;
2204                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2205                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2206                 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]);
2207                 
2208                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2209                 
2210                 printf("[");
2211                 for (i = 0; i < (*tot); i++) {
2212                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2213                 }
2214                 printf("]),\\\n");
2215         }
2216 #endif
2217 }
2218
2219 /*
2220  * # This script creates faces in a blender scene from printed data above.
2221  *
2222  * project_ls = [
2223  * ...(output from above block)...
2224  * ]
2225  *
2226  * from Blender import Scene, Mesh, Window, sys, Mathutils
2227  *
2228  * import bpy
2229  *
2230  * V = Mathutils.Vector
2231  *
2232  * def main():
2233  *     sce = bpy.data.scenes.active
2234  *     
2235  *     for item in project_ls:
2236  *         bb = item[0]
2237  *         uv = item[1]
2238  *         poly = item[2]
2239  *         
2240  *         me = bpy.data.meshes.new()
2241  *         ob = sce.objects.new(me)
2242  *         
2243  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2244  *         me.faces.extend([(0,1,2,3),])
2245  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2246  *         me.faces.extend([(4,5,6),])
2247  *         
2248  *         vs = [V(p).xyz for p in poly]
2249  *         print len(vs)
2250  *         l = len(me.verts)
2251  *         me.verts.extend(vs)
2252  *         
2253  *         i = l
2254  *         while i < len(me.verts):
2255  *             ii = i + 1
2256  *             if ii == len(me.verts):
2257  *                 ii = l
2258  *             me.edges.extend([i, ii])
2259  *             i += 1
2260  * 
2261  * if __name__ == '__main__':
2262  *     main()
2263  */
2264
2265
2266 #undef ISECT_1
2267 #undef ISECT_2
2268 #undef ISECT_3
2269 #undef ISECT_4
2270 #undef ISECT_ALL3
2271 #undef ISECT_ALL4
2272
2273         
2274 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2275  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2276 static int IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2277 {
2278         int i;
2279         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2280                 return 0;
2281         
2282         for (i = 1; i < tot; i++) {
2283                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2284                         return 0;
2285                 
2286         }
2287         
2288         return 1;
2289 }
2290 static int IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2291 {
2292         int i;
2293         int side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2294         
2295         for (i = 1; i < tot; i++) {
2296                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2297                         return 0;
2298                 
2299         }
2300         
2301         return 1;
2302 }
2303
2304 /* One of the most important function for projectiopn painting, since it selects the pixels to be added into each bucket.
2305  * initialize pixels from this face where it intersects with the bucket_index, optionally initialize pixels for removing seams */
2306 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)
2307 {
2308         /* Projection vars, to get the 3D locations into screen space  */
2309         MemArena *arena = ps->arena_mt[thread_index];
2310         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2311         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2312         
2313         const MFace *mf = ps->dm_mface + face_index;
2314         const MTFace *tf = ps->dm_mtface + face_index;
2315         
2316         /* UV/pixel seeking data */
2317         int x; /* Image X-Pixel */
2318         int y; /* Image Y-Pixel */
2319         float mask;
2320         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2321         
2322         int side;
2323         float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to mf->v1,2,3 or mf->v1,3,4 */
2324         
2325         float *vCo[4]; /* vertex screenspace coords */
2326         
2327         float w[3], wco[3];
2328         
2329         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to tf->uv[0],1,2 or tf->uv[0],2,3 */
2330         float pixelScreenCo[4];
2331         
2332         rcti bounds_px; /* ispace bounds */
2333         /* vars for getting uvspace bounds */
2334         
2335         float tf_uv_pxoffset[4][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2336         float xhalfpx, yhalfpx;
2337         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2338         
2339         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2340         
2341         int i1, i2, i3;
2342         
2343         float uv_clip[8][2];
2344         int uv_clip_tot;
2345         const short is_ortho = ps->is_ortho;
2346         const short do_backfacecull = ps->do_backfacecull;
2347         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2348         
2349         vCo[0] = ps->dm_mvert[mf->v1].co;
2350         vCo[1] = ps->dm_mvert[mf->v2].co;
2351         vCo[2] = ps->dm_mvert[mf->v3].co;
2352         
2353         
2354         /* Use tf_uv_pxoffset instead of tf->uv so we can offset the UV half a pixel
2355          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2356          * problems when wrapping negative coords */
2357         xhalfpx = (0.5f + (PROJ_GEOM_TOLERANCE / 3.0f)) / ibuf_xf;
2358         yhalfpx = (0.5f + (PROJ_GEOM_TOLERANCE / 4.0f)) / ibuf_yf;
2359         
2360         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2361          * Needed to add this offset since UV coords are often quads aligned to pixels.
2362          * In this case pixels can be exactly between 2 triangles causing nasty
2363          * artifacts.
2364          * 
2365          * This workaround can be removed and painting will still work on most cases
2366          * but since the first thing most people try is painting onto a quad- better make it work.
2367          */
2368
2369
2370
2371         tf_uv_pxoffset[0][0] = tf->uv[0][0] - xhalfpx;
2372         tf_uv_pxoffset[0][1] = tf->uv[0][1] - yhalfpx;
2373
2374         tf_uv_pxoffset[1][0] = tf->uv[1][0] - xhalfpx;
2375         tf_uv_pxoffset[1][1] = tf->uv[1][1] - yhalfpx;
2376         
2377         tf_uv_pxoffset[2][0] = tf->uv[2][0] - xhalfpx;
2378         tf_uv_pxoffset[2][1] = tf->uv[2][1] - yhalfpx;  
2379         
2380         if (mf->v4) {
2381                 vCo[3] = ps->dm_mvert[mf->v4].co;
2382                 
2383                 tf_uv_pxoffset[3][0] = tf->uv[3][0] - xhalfpx;
2384                 tf_uv_pxoffset[3][1] = tf->uv[3][1] - yhalfpx;
2385                 side = 1;
2386         }
2387         else {
2388                 side = 0;
2389         }
2390         
2391         do {
2392                 if (side == 1) {
2393                         i1 = 0; i2 = 2; i3 = 3;
2394                 }
2395                 else {
2396                         i1 = 0; i2 = 1; i3 = 2;
2397                 }
2398                 
2399                 uv1co = tf_uv_pxoffset[i1]; // was tf->uv[i1];
2400                 uv2co = tf_uv_pxoffset[i2]; // was tf->uv[i2];
2401                 uv3co = tf_uv_pxoffset[i3]; // was tf->uv[i3];
2402
2403                 v1coSS = ps->screenCoords[(*(&mf->v1 + i1))];
2404                 v2coSS = ps->screenCoords[(*(&mf->v1 + i2))];
2405                 v3coSS = ps->screenCoords[(*(&mf->v1 + i3))];
2406                 
2407                 /* This funtion gives is a concave polyline in UV space from the clipped quad and tri*/
2408                 project_bucket_clip_face(
2409                         is_ortho, bucket_bounds,
2410                         v1coSS, v2coSS, v3coSS,
2411                         uv1co, uv2co, uv3co,
2412                         uv_clip, &uv_clip_tot
2413                         );
2414
2415                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2416 #if 0
2417                 if (uv_clip_tot > 6) {
2418                         printf("this should never happen! %d\n", uv_clip_tot);
2419                 }
2420 #endif
2421
2422                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2423
2424                         if (clamp_u) {
2425                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2426                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2427                         }
2428
2429                         if (clamp_v) {
2430                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2431                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2432                         }
2433
2434                         /* clip face and */
2435                         
2436                         has_isect = 0;
2437                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2438                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2439                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2440
2441                                 has_x_isect = 0;
2442                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2443                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2444                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2445                                         
2446                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2447                                          * could check the poly direction but better to do this */
2448                                         if ((do_backfacecull == TRUE  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2449                                             (do_backfacecull == FALSE && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2450                                         {
2451                                                 
2452                                                 has_x_isect = has_isect = 1;
2453                                                 
2454                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2455                                                 else          screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2456                                                 
2457                                                 /* a pity we need to get the worldspace pixel location here */
2458                                                 if (do_clip) {
2459                                                         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);
2460                                                         if (ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2461                                                                 continue; /* Watch out that no code below this needs to run */
2462                                                         }
2463                                                 }
2464                                                 
2465                                                 /* Is this UV visible from the view? - raytrace */
2466                                                 /* project_paint_PickFace is less complex, use for testing */
2467                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == face_index) {
2468                                                 if ((ps->do_occlude == FALSE) ||
2469                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2470                                                 {
2471                                                         
2472                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2473                                                         
2474                                                         if (mask > 0.0f) {
2475                                                                 BLI_linklist_prepend_arena(
2476                                                                         bucketPixelNodes,
2477                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index, image_index, pixelScreenCo, side, w),
2478                                                                         arena
2479                                                                         );
2480                                                         }
2481                                                 }
2482                                                 
2483                                         }
2484 //#if 0
2485                                         else if (has_x_isect) {
2486                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2487                                                 break;
2488                                         }
2489 //#endif
2490                                 }
2491                                 
2492                                 
2493 #if 0           /* TODO - investigate why this dosnt work sometimes! it should! */
2494                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2495                                 if (has_x_isect == 0 && has_isect) {
2496                                         break;
2497                                 }
2498 #endif
2499                         }
2500                 }
2501         } while (side--);
2502
2503         
2504         
2505 #ifndef PROJ_DEBUG_NOSEAMBLEED
2506         if (ps->seam_bleed_px > 0.0f) {
2507                 int face_seam_flag;
2508                 
2509                 if (ps->thread_tot > 1)
2510                         BLI_lock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2511                 
2512                 face_seam_flag = ps->faceSeamFlags[face_index];
2513                 
2514                 /* are any of our edges un-initialized? */
2515                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_NOSEAM1)) == 0 ||
2516                     (face_seam_flag & (PROJ_FACE_SEAM2 | PROJ_FACE_NOSEAM2)) == 0 ||
2517                     (face_seam_flag & (PROJ_FACE_SEAM3 | PROJ_FACE_NOSEAM3)) == 0 ||
2518                     (face_seam_flag & (PROJ_FACE_SEAM4 | PROJ_FACE_NOSEAM4)) == 0)
2519                 {
2520                         project_face_seams_init(ps, face_index, mf->v4);
2521                         face_seam_flag = ps->faceSeamFlags[face_index];
2522                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3, flag&PROJ_FACE_SEAM4);
2523                 }
2524                 
2525                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_SEAM2 | PROJ_FACE_SEAM3 | PROJ_FACE_SEAM4)) == 0) {
2526                         
2527                         if (ps->thread_tot > 1)
2528                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2529                         
2530                 }
2531                 else {
2532                         /* we have a seam - deal with it! */
2533                         
2534                         /* Now create new UV's for the seam face */
2535                         float (*outset_uv)[2] = ps->faceSeamUVs[face_index];
2536                         float insetCos[4][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2537
2538                         float fac;
2539                         float *vCoSS[4]; /* vertex screenspace coords */
2540                         
2541                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2542                         float edge_verts_inset_clip[2][3];
2543                         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 */
2544                         
2545                         float seam_subsection[4][2];
2546                         float fac1, fac2, ftot;
2547                         
2548                         
2549                         if (outset_uv[0][0] == FLT_MAX) /* first time initialize */
2550                                 uv_image_outset(tf_uv_pxoffset, outset_uv, ps->seam_bleed_px, ibuf->x, ibuf->y, mf->v4);
2551                         
2552                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2553                         if (ps->thread_tot > 1)
2554                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2555                         
2556                         vCoSS[0] = ps->screenCoords[mf->v1];
2557                         vCoSS[1] = ps->screenCoords[mf->v2];
2558                         vCoSS[2] = ps->screenCoords[mf->v3];
2559                         if (mf->v4)
2560                                 vCoSS[3] = ps->screenCoords[mf->v4];
2561                         
2562                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2563                         if (is_ortho) {
2564                                 if (mf->v4) scale_quad(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2565                                 else        scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2566                         }
2567                         else {
2568                                 if (mf->v4) scale_quad(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2569                                 else        scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2570                         }
2571                         
2572                         side = 0; /* for triangles this wont need to change */
2573                         
2574                         for (fidx1 = 0; fidx1 < (mf->v4 ? 4 : 3); fidx1++) {
2575                                 if (mf->v4) fidx2 = (fidx1 == 3) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2,3) -> (1,2,3,0) */
2576                                 else        fidx2 = (fidx1 == 2) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2) -> (1,2,0) */
2577                                 
2578                                 if ((face_seam_flag & (1 << fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2579                                     line_clip_rect2f(bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1]))
2580                                 {
2581
2582                                         ftot = len_v2v2(vCoSS[fidx1], vCoSS[fidx2]); /* screenspace edge length */
2583                                         
2584                                         if (ftot > 0.0f) { /* avoid div by zero */
2585                                                 if (mf->v4) {
2586                                                         if (fidx1 == 2 || fidx2 == 2) side = 1;
2587                                                         else side = 0;
2588                                                 }
2589                                                 
2590                                                 fac1 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[0]) / ftot;
2591                                                 fac2 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[1]) / ftot;
2592                                                 
2593                                                 interp_v2_v2v2(seam_subsection[0], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac1);
2594                                                 interp_v2_v2v2(seam_subsection[1], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac2);
2595
2596                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2597                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2598                                                 
2599                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2600                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2601                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2602                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2603                                                 
2604
2605                                                 if (pixel_bounds_uv(seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3], &bounds_px, ibuf->x, ibuf->y, 1)) {
2606                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2607                                                         
2608                                                         has_isect = 0;
2609                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2610                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2611                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2612                                                                 
2613                                                                 has_x_isect = 0;
2614                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2615                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2616                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2617                                                                         
2618                                                                         /* test we're inside uvspace bucket and triangle bounds */
2619                                                                         if (isect_point_quad_v2(uv, seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3])) {
2620                                                                                 
2621                                                                                 /* We need to find the closest point along the face edge,
2622                                                                                  * getting the screen_px_from_*** wont work because our actual location
2623                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2624                                                                                  * our location on the side of the face's UV */
2625 #if 0
2626                                                                                 if (is_ortho) screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2627                                                                                 else          screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2628 #endif
2629                                                                                 
2630                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2631                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2632                                                                                 
2633                                                                                 fac = line_point_factor_v2(uv, seam_subsection[0], seam_subsection[1]);
2634                                                                                 if      (fac < 0.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[0]); }
2635                                                                                 else if (fac > 1.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[1]); }
2636                                                                                 else                 { interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac); }
2637                                                                                 
2638                                                                                 if (!is_ortho) {
2639                                                                                         pixelScreenCo[3] = 1.0f;
2640                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2641                                                                                         pixelScreenCo[0] = (float)(ps->winx / 2.0f) + (ps->winx / 2.0f) * pixelScreenCo[0] / pixelScreenCo[3];
2642                                                                                         pixelScreenCo[1] = (float)(ps->winy / 2.0f) + (ps->winy / 2.0f) * pixelScreenCo[1] / pixelScreenCo[3];
2643                                                                                         pixelScreenCo[2] = pixelScreenCo[2] / pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2644                                                                                 }
2645                                                                                 
2646                                                                                 if ((ps->do_occlude == FALSE) ||
2647                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2648                                                                                 {
2649                                                                                         /* Only bother calculating the weights if we intersect */
2650                                                                                         if (ps->do_mask_normal || ps->dm_mtface_clone) {
2651 #if 1
2652                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2653                                                                                                 float uv_close[2];
2654                                                                                                 float fac = closest_to_line_v2(uv_close, uv, tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2]);
2655                                                                                                 if      (fac < 0.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx1]);
2656                                                                                                 else if (fac > 1.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx2]);
2657
2658                                                                                                 if (side) {
2659                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[2], tf_uv_pxoffset[3], uv_close, w);
2660                                                                                                 }
2661                                                                                                 else {
2662                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[1], tf_uv_pxoffset[2], uv_close, w);
2663                                                                                                 }
2664 #else                                                                                   /* this is buggy with quads, don't use for now */
2665
2666                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2667                                                                                                 fac = fac1 + (fac * (fac2 - fac1));
2668
2669                                                                                                 w[0] = w[1] = w[2] = 0.0;
2670                                                                                                 if (side) {
2671                                                                                                         w[fidx1 ? fidx1 - 1 : 0] = 1.0f - fac;
2672                                                                                                         w[fidx2 ? fidx2 - 1 : 0] = fac;
2673                                                                                                 }
2674                                                                                                 else {
2675                                                                                                         w[fidx1] = 1.0f - fac;
2676                                                                                                         w[fidx2] = fac;
2677                                                                                                 }
2678 #endif
2679                                                                                         }
2680                                                                                         
2681                                                                                         /* a pity we need to get the worldspace pixel location here */
2682                                                                                         if (do_clip) {
2683                                                                                                 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);
2684                                                                                                 else      interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
2685
2686                                                                                                 if (ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2687                                                                                                         continue; /* Watch out that no code below this needs to run */
2688                                                                                                 }
2689                                                                                         }
2690                                                                                         
2691                                                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2692                                                                                         
2693                                                                                         if (mask > 0.0f) {
2694                                                                                                 BLI_linklist_prepend_arena(
2695                                                                                                         bucketPixelNodes,
2696                                                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index, image_index, pixelScreenCo, side, w),
2697                                                                                                         arena
2698                                                                                                         );
2699                                                                                         }
2700                                                                                         
2701                                                                                 }
2702                                                                         }
2703                                                                         else if (has_x_isect) {
2704                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2705                                                                                 break;
2706                                                                         }
2707                                                                 }
2708                                                                 
2709 #if 0                           /* TODO - investigate why this dosnt work sometimes! it should! */
2710                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2711                                                                 if (has_x_isect == 0 && has_isect) {
2712                                                                         break;
2713                                                                 }
2714 #endif
2715                                                         }
2716                                                 }
2717                                         }
2718                                 }
2719                         }
2720                 }
2721         }
2722 #endif // PROJ_DEBUG_NOSEAMBLEED
2723 }
2724
2725
2726 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2727 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2728 {
2729         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2730         /* 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 */
2731         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 */
2732         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2733         
2734         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2735         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2736         
2737         /* in case the rect is outside the mesh 2d bounds */
2738         CLAMP(bucketMin[0], 0, ps->buckets_x);
2739         CLAMP(bucketMin[1], 0, ps->buckets_y);
2740         
2741         CLAMP(bucketMax[0], 0, ps->buckets_x);
2742         CLAMP(bucketMax[1], 0, ps->buckets_y);
2743 }
2744
2745 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2746 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2747 {
2748         bucket_bounds->xmin = ps->screenMin[0] + ((bucket_x) * (ps->screen_width / ps->buckets_x));     /* left */
2749         bucket_bounds->xmax = ps->screenMin[0] + ((bucket_x + 1) * (ps->screen_width / ps->buckets_x)); /* right */
2750         
2751         bucket_bounds->ymin = ps->screenMin[1] + ((bucket_y) * (ps->screen_height / ps->buckets_y));      /* bottom */
2752         bucket_bounds->ymax = ps->screenMin[1] + ((bucket_y + 1) * (ps->screen_height  / ps->buckets_y)); /* top */
2753 }
2754
2755 /* Fill this bucket with pixels from the faces that intersect it.
2756  * 
2757  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2758 static void project_bucket_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, rctf *bucket_bounds)
2759 {
2760         LinkNode *node;
2761         int face_index, image_index = 0;
2762         ImBuf *ibuf = NULL;
2763         Image *tpage_last = NULL, *tpage;
2764         Image *ima = NULL;
2765
2766         if (ps->image_tot == 1) {
2767                 /* Simple loop, no context switching */
2768                 ibuf = ps->projImages[0].ibuf;
2769                 ima = ps->projImages[0].ima;
2770
2771                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2772                         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);
2773                 }
2774         }
2775         else {
2776                 
2777                 /* More complicated loop, switch between images */
2778                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2779                         face_index = GET_INT_FROM_POINTER(node->link);
2780                                 
2781                         /* Image context switching */
2782                         tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
2783                         if (tpage_last != tpage) {
2784                                 tpage_last = tpage;
2785
2786                                 for (image_index = 0; image_index < ps->image_tot; image_index++) {
2787                                         if (ps->projImages[image_index].ima == tpage_last) {
2788                                                 ibuf = ps->projImages[image_index].ibuf;
2789                                                 ima = ps->projImages[image_index].ima;
2790                                                 break;
2791                                         }
2792                                 }
2793                         }
2794                         /* context switching done */
2795                         
2796                         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);
2797                 }
2798         }
2799         
2800         ps->bucketFlags[bucket_index] |= PROJ_BUCKET_INIT;
2801 }
2802
2803
2804 /* We want to know if a bucket and a face overlap in screen-space
2805  * 
2806  * Note, if this ever returns false positives its not that bad, since a face in the bounding area will have its pixels
2807  * calculated when it might not be needed later, (at the moment at least)
2808  * obviously it shouldn't have bugs though */
2809
2810 static int project_bucket_face_isect(ProjPaintState *ps, int bucket_x, int bucket_y, const MFace *mf)
2811 {
2812         /* TODO - replace this with a tricker method that uses sideofline for all screenCoords's edges against the closest bucket corner */
2813         rctf bucket_bounds;
2814         float p1[2], p2[2], p3[2], p4[2];
2815         float *v, *v1, *v2, *v3, *v4 = NULL;
2816         int fidx;
2817         
2818         project_bucket_bounds(ps, bucket_x, bucket_y, &bucket_bounds);
2819         
2820         /* Is one of the faces verts in the bucket bounds? */
2821         
2822         fidx = mf->v4 ? 3 : 2;
2823         do {
2824                 v = ps->screenCoords[(*(&mf->v1 + fidx))];
2825                 if (BLI_rctf_isect_pt_v(&bucket_bounds, v)) {
2826                         return 1;
2827                 }
2828         } while (fidx--);
2829         
2830         v1 = ps->screenCoords[mf->v1];
2831         v2 = ps->screenCoords[mf->v2];
2832         v3 = ps->screenCoords[mf->v3];
2833         if (mf->v4) {
2834                 v4 = ps->screenCoords[mf->v4];
2835         }
2836         
2837         p1[0] = bucket_bounds.xmin; p1[1] = bucket_bounds.ymin;
2838         p2[0] = bucket_bounds.xmin; p2[1] = bucket_bounds.ymax;
2839         p3[0] = bucket_bounds.xmax; p3[1] = bucket_bounds.ymax;
2840         p4[0] = bucket_bounds.xmax; p4[1] = bucket_bounds.ymin;
2841                 
2842         if (mf->v4) {
2843                 if (isect_point_quad_v2(p1, v1, v2, v3, v4) ||
2844                     isect_point_quad_v2(p2, v1, v2, v3, v4) ||
2845                     isect_point_quad_v2(p3, v1, v2, v3, v4) ||
2846                     isect_point_quad_v2(p4, v1, v2, v3, v4) ||
2847
2848                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2849                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3) || isect_line_line_v2(p1, p2, v3, v4)) ||
2850                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3) || isect_line_line_v2(p2, p3, v3, v4)) ||
2851                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3) || isect_line_line_v2(p3, p4, v3, v4)) ||
2852                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3) || isect_line_line_v2(p4, p1, v3, v4)))
2853                 {
2854                         return 1;
2855                 }
2856         }
2857         else {
2858                 if (isect_point_tri_v2(p1, v1, v2, v3) ||