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