Merge branch 'master' into blender2.8
[blender.git] / source / blender / editors / sculpt_paint / paint_image_proj.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_proj.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_blenlib.h"
44 #include "BLI_linklist.h"
45 #include "BLI_math.h"
46 #include "BLI_math_bits.h"
47 #include "BLI_math_color_blend.h"
48 #include "BLI_memarena.h"
49 #include "BLI_threads.h"
50 #include "BLI_utildefines.h"
51
52 #include "BLT_translation.h"
53
54
55 #include "IMB_imbuf.h"
56 #include "IMB_imbuf_types.h"
57
58 #include "DNA_brush_types.h"
59 #include "DNA_material_types.h"
60 #include "DNA_mesh_types.h"
61 #include "DNA_node_types.h"
62 #include "DNA_object_types.h"
63
64 #include "BKE_camera.h"
65 #include "BKE_context.h"
66 #include "BKE_colortools.h"
67 #include "BKE_DerivedMesh.h"
68 #include "BKE_idprop.h"
69 #include "BKE_brush.h"
70 #include "BKE_image.h"
71 #include "BKE_library.h"
72 #include "BKE_main.h"
73 #include "BKE_material.h"
74 #include "BKE_mesh.h"
75 #include "BKE_mesh_mapping.h"
76 #include "BKE_node.h"
77 #include "BKE_paint.h"
78 #include "BKE_report.h"
79 #include "BKE_scene.h"
80 #include "BKE_texture.h"
81
82 #include "DEG_depsgraph.h"
83
84 #include "UI_interface.h"
85
86 #include "ED_mesh.h"
87 #include "ED_node.h"
88 #include "ED_paint.h"
89 #include "ED_screen.h"
90 #include "ED_uvedit.h"
91 #include "ED_view3d.h"
92
93 #include "GPU_extensions.h"
94
95 #include "WM_api.h"
96 #include "WM_types.h"
97
98 #include "RNA_access.h"
99 #include "RNA_define.h"
100 #include "RNA_enum_types.h"
101
102 #include "GPU_draw.h"
103
104 #include "IMB_colormanagement.h"
105
106 #include "bmesh.h"
107 //#include "bmesh_tools.h"
108
109 #include "paint_intern.h"
110
111 static void partial_redraw_array_init(ImagePaintPartialRedraw *pr);
112
113 /* Defines and Structs */
114 /* FTOCHAR as inline function */
115 BLI_INLINE unsigned char f_to_char(const float val)
116 {
117         return FTOCHAR(val);
118 }
119
120 /* ProjectionPaint defines */
121
122 /* approx the number of buckets to have under the brush,
123  * used with the brush size to set the ps->buckets_x and ps->buckets_y value.
124  *
125  * When 3 - a brush should have ~9 buckets under it at once
126  * ...this helps for threading while painting as well as
127  * avoiding initializing pixels that wont touch the brush */
128 #define PROJ_BUCKET_BRUSH_DIV 4
129
130 #define PROJ_BUCKET_RECT_MIN 4
131 #define PROJ_BUCKET_RECT_MAX 256
132
133 #define PROJ_BOUNDBOX_DIV 8
134 #define PROJ_BOUNDBOX_SQUARED  (PROJ_BOUNDBOX_DIV * PROJ_BOUNDBOX_DIV)
135
136 //#define PROJ_DEBUG_PAINT 1
137 //#define PROJ_DEBUG_NOSEAMBLEED 1
138 //#define PROJ_DEBUG_PRINT_CLIP 1
139 #define PROJ_DEBUG_WINCLIP 1
140
141
142 #ifndef PROJ_DEBUG_NOSEAMBLEED
143 /* projectFaceSeamFlags options */
144 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
145 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
146 #define PROJ_FACE_SEAM1 (1 << 0)  /* If this face has a seam on any of its edges */
147 #define PROJ_FACE_SEAM2 (1 << 1)
148 #define PROJ_FACE_SEAM3 (1 << 2)
149
150 #define PROJ_FACE_NOSEAM1   (1 << 4)
151 #define PROJ_FACE_NOSEAM2   (1 << 5)
152 #define PROJ_FACE_NOSEAM3   (1 << 6)
153
154 /* face winding */
155 #define PROJ_FACE_WINDING_INIT 1
156 #define PROJ_FACE_WINDING_CW 2
157
158 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
159  * as this number approaches  1.0f the likelihood increases of float precision errors where
160  * it is occluded by an adjacent face */
161 #define PROJ_FACE_SCALE_SEAM    0.99f
162 #endif  /* PROJ_DEBUG_NOSEAMBLEED */
163
164
165 #define PROJ_SRC_VIEW       1
166 #define PROJ_SRC_IMAGE_CAM  2
167 #define PROJ_SRC_IMAGE_VIEW 3
168 #define PROJ_SRC_VIEW_FILL  4
169
170 #define PROJ_VIEW_DATA_ID "view_data"
171 #define PROJ_VIEW_DATA_SIZE (4 * 4 + 4 * 4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
172
173 #define PROJ_BUCKET_NULL        0
174 #define PROJ_BUCKET_INIT        (1 << 0)
175 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
176
177 /* used for testing doubles, if a point is on a line etc */
178 #define PROJ_GEOM_TOLERANCE 0.00075f
179 #define PROJ_PIXEL_TOLERANCE 0.01f
180
181 /* vert flags */
182 #define PROJ_VERT_CULL 1
183
184 /* to avoid locking in tile initialization */
185 #define TILE_PENDING SET_INT_IN_POINTER(-1)
186
187 /* This is mainly a convenience struct used so we can keep an array of images we use -
188  * their imbufs, etc, in 1 array, When using threads this array is copied for each thread
189  * because 'partRedrawRect' and 'touch' values would not be thread safe */
190 typedef struct ProjPaintImage {
191         Image *ima;
192         ImBuf *ibuf;
193         ImagePaintPartialRedraw *partRedrawRect;
194         volatile void **undoRect; /* only used to build undo tiles during painting */
195         unsigned short **maskRect; /* the mask accumulation must happen on canvas, not on space screen bucket.
196                                     * Here we store the mask rectangle */
197         bool **valid; /* store flag to enforce validation of undo rectangle */
198         bool touch;
199 } ProjPaintImage;
200
201 /**
202  * Handle for stroke (operator customdata)
203  */
204 typedef struct ProjStrokeHandle {
205         /* Support for painting from multiple views at once,
206          * currently used to implement symmetry painting,
207          * we can assume at least the first is set while painting. */
208         struct ProjPaintState *ps_views[8];
209         int ps_views_tot;
210         int symmetry_flags;
211
212         int orig_brush_size;
213
214         bool need_redraw;
215
216         /* trick to bypass regular paint and allow clone picking */
217         bool is_clone_cursor_pick;
218
219         /* In ProjPaintState, only here for convenience */
220         Scene *scene;
221         Brush *brush;
222 } ProjStrokeHandle;
223
224 /* Main projection painting struct passed to all projection painting functions */
225 typedef struct ProjPaintState {
226         View3D *v3d;
227         RegionView3D *rv3d;
228         ARegion *ar;
229         Scene *scene;
230         int source; /* PROJ_SRC_**** */
231
232         /* the paint color. It can change depending of inverted mode or not */
233         float paint_color[3];
234         float paint_color_linear[3];
235         float dither;
236
237         Brush *brush;
238         short tool, blend, mode;
239
240         float brush_size;
241         Object *ob;
242         /* for symmetry, we need to store modified object matrix */
243         float obmat[4][4];
244         float obmat_imat[4][4];
245         /* end similarities with ImagePaintState */
246
247         Image *stencil_ima;
248         Image *canvas_ima;
249         Image *clone_ima;
250         float stencil_value;
251
252         /* projection painting only */
253         MemArena *arena_mt[BLENDER_MAX_THREADS]; /* for multithreading, the first item is sometimes used for non threaded cases too */
254         LinkNode **bucketRect;              /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
255         LinkNode **bucketFaces;             /* bucketRect aligned array linkList of faces overlapping each bucket */
256         unsigned char *bucketFlags;         /* store if the bucks have been initialized  */
257
258         char *vertFlags;                    /* store options per vert, now only store if the vert is pointing away from the view */
259         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 */
260         int buckets_y;
261
262         int pixel_sizeof;           /* result of project_paint_pixel_sizeof(), constant per stroke */
263
264         int image_tot;              /* size of projectImages array */
265
266         float (*screenCoords)[4];   /* verts projected into floating point screen space */
267         float screenMin[2];         /* 2D bounds for mesh verts on the screen's plane (screenspace) */
268         float screenMax[2];
269         float screen_width;         /* Calculated from screenMin & screenMax */
270         float screen_height;
271         int winx, winy;             /* from the carea or from the projection render */
272
273         /* options for projection painting */
274         bool  do_layer_clone;
275         bool  do_layer_stencil;
276         bool  do_layer_stencil_inv;
277         bool  do_stencil_brush;
278         bool  do_material_slots;
279
280         bool  do_occlude;               /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
281         bool  do_backfacecull;          /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
282         bool  do_mask_normal;           /* mask out pixels based on their normals */
283         bool  do_mask_cavity;           /* mask out pixels based on cavity */
284         bool  do_new_shading_nodes;     /* cache BKE_scene_use_new_shading_nodes value */
285         float normal_angle;             /* what angle to mask at */
286         float normal_angle__cos;         /* cos(normal_angle), faster to compare */
287         float normal_angle_inner;
288         float normal_angle_inner__cos;
289         float normal_angle_range;       /* difference between normal_angle and normal_angle_inner, for easy access */
290
291         bool do_face_sel;               /* quick access to (me->editflag & ME_EDIT_PAINT_FACE_SEL) */
292         bool is_ortho;
293         bool is_flip_object;            /* the object is negative scaled */
294         bool do_masking;              /* use masking during painting. Some operations such as airbrush may disable */
295         bool is_texbrush;              /* only to avoid running  */
296         bool is_maskbrush;            /* mask brush is applied before masking */
297 #ifndef PROJ_DEBUG_NOSEAMBLEED
298         float seam_bleed_px;
299 #endif
300         /* clone vars */
301         float cloneOffset[2];
302
303         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
304         float projectMatInv[4][4];  /* inverse of projectMat */
305         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
306         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
307         float clipsta, clipend;
308
309         /* reproject vars */
310         Image *reproject_image;
311         ImBuf *reproject_ibuf;
312         bool   reproject_ibuf_free_float;
313         bool   reproject_ibuf_free_uchar;
314
315         /* threads */
316         int thread_tot;
317         int bucketMin[2];
318         int bucketMax[2];
319         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
320
321         struct CurveMapping *cavity_curve;
322         BlurKernel *blurkernel;
323
324
325
326         /* -------------------------------------------------------------------- */
327         /* Vars shared between multiple views (keep last) */
328         /**
329          * This data is owned by ``ProjStrokeHandle.ps_views[0]``,
330          * all other views re-use the data.
331          */
332
333 #define PROJ_PAINT_STATE_SHARED_MEMCPY(ps_dst, ps_src) \
334         MEMCPY_STRUCT_OFS(ps_dst, ps_src, is_shared_user)
335
336 #define PROJ_PAINT_STATE_SHARED_CLEAR(ps) \
337         MEMSET_STRUCT_OFS(ps, 0, is_shared_user)
338
339         bool is_shared_user;
340
341         ProjPaintImage *projImages;
342         float *cavities;            /* cavity amount for vertices */
343
344 #ifndef PROJ_DEBUG_NOSEAMBLEED
345         char *faceSeamFlags;                /* store info about faces, if they are initialized etc*/
346         char *faceWindingFlags;             /* save the winding of the face in uv space, helps as an extra validation step for seam detection */
347         float (*faceSeamUVs)[3][2];         /* expanded UVs for faces to use as seams */
348         LinkNode **vertFaces;               /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
349 #endif
350
351         SpinLock *tile_lock;
352
353         DerivedMesh    *dm;
354         int  dm_totlooptri;
355         int  dm_totpoly;
356         int  dm_totedge;
357         int  dm_totvert;
358         bool dm_release;
359
360         const MVert    *dm_mvert;
361         const MEdge    *dm_medge;
362         const MPoly    *dm_mpoly;
363         const MLoop    *dm_mloop;
364         const MLoopTri *dm_mlooptri;
365
366         const MLoopUV  *dm_mloopuv_stencil;
367
368         /**
369          * \note These UV layers are aligned to \a dm_mpoly
370          * but each pointer references the start of the layer,
371          * so a loop indirection is needed as well.
372          */
373         const MLoopUV **dm_mloopuv;
374         const MLoopUV **dm_mloopuv_clone;    /* other UV map, use for cloning between layers */
375
376         bool use_colormanagement;
377 } ProjPaintState;
378
379 typedef union pixelPointer {
380         float *f_pt;            /* float buffer */
381         unsigned int *uint_pt; /* 2 ways to access a char buffer */
382         unsigned char *ch_pt;
383 } PixelPointer;
384
385 typedef union pixelStore {
386         unsigned char ch[4];
387         unsigned int uint;
388         float f[4];
389 } PixelStore;
390
391 typedef struct ProjPixel {
392         float projCoSS[2]; /* the floating point screen projection of this pixel */
393         float worldCoSS[3];
394
395         short x_px, y_px;
396
397         unsigned short image_index; /* if anyone wants to paint onto more than 65535 images they can bite me */
398         unsigned char bb_cell_index;
399
400         /* for various reasons we may want to mask out painting onto this pixel */
401         unsigned short mask;
402
403         /* Only used when the airbrush is disabled.
404          * Store the max mask value to avoid painting over an area with a lower opacity
405          * with an advantage that we can avoid touching the pixel at all, if the
406          * new mask value is lower then mask_accum */
407         unsigned short *mask_accum;
408
409         /* horrible hack, store tile valid flag pointer here to re-validate tiles used for anchored and drag-dot strokes */
410         bool *valid;
411
412         PixelPointer origColor;
413         PixelStore newColor;
414         PixelPointer pixel;
415 } ProjPixel;
416
417 typedef struct ProjPixelClone {
418         struct ProjPixel __pp;
419         PixelStore clonepx;
420 } ProjPixelClone;
421
422 /* undo tile pushing */
423 typedef struct {
424         SpinLock *lock;
425         bool masked;
426         unsigned short tile_width;
427         ImBuf **tmpibuf;
428         ProjPaintImage *pjima;
429 } TileInfo;
430
431
432
433 /* -------------------------------------------------------------------- */
434
435 /** \name MLoopTri accessor functions.
436  * \{ */
437
438 BLI_INLINE const MPoly *ps_tri_index_to_mpoly(const ProjPaintState *ps, int tri_index)
439 {
440         return &ps->dm_mpoly[ps->dm_mlooptri[tri_index].poly];
441 }
442
443 #define PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) \
444         ps->dm_mloop[lt->tri[0]].v, \
445         ps->dm_mloop[lt->tri[1]].v, \
446         ps->dm_mloop[lt->tri[2]].v,
447
448 #define PS_LOOPTRI_AS_UV_3(uvlayer, lt) \
449         uvlayer[lt->poly][lt->tri[0]].uv, \
450         uvlayer[lt->poly][lt->tri[1]].uv, \
451         uvlayer[lt->poly][lt->tri[2]].uv,
452
453 #define PS_LOOPTRI_ASSIGN_UV_3(uv_tri, uvlayer, lt)  { \
454         (uv_tri)[0] = uvlayer[lt->poly][lt->tri[0]].uv; \
455         (uv_tri)[1] = uvlayer[lt->poly][lt->tri[1]].uv; \
456         (uv_tri)[2] = uvlayer[lt->poly][lt->tri[2]].uv; \
457 } ((void)0)
458
459 /** \} */
460
461
462
463 /* Finish projection painting structs */
464
465 static TexPaintSlot *project_paint_face_paint_slot(const ProjPaintState *ps, int tri_index)
466 {
467         const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
468         Material *ma = ps->dm->mat[mp->mat_nr];
469         return ma ? ma->texpaintslot + ma->paint_active_slot : NULL;
470 }
471
472 static Image *project_paint_face_paint_image(const ProjPaintState *ps, int tri_index)
473 {
474         if (ps->do_stencil_brush) {
475                 return ps->stencil_ima;
476         }
477         else {
478                 const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
479                 Material *ma = ps->dm->mat[mp->mat_nr];
480                 TexPaintSlot *slot = ma ? ma->texpaintslot + ma->paint_active_slot : NULL;
481                 return slot ? slot->ima : ps->canvas_ima;
482         }
483 }
484
485 static TexPaintSlot *project_paint_face_clone_slot(const ProjPaintState *ps, int tri_index)
486 {
487         const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
488         Material *ma = ps->dm->mat[mp->mat_nr];
489         return ma ? ma->texpaintslot + ma->paint_clone_slot : NULL;
490 }
491
492 static Image *project_paint_face_clone_image(const ProjPaintState *ps, int tri_index)
493 {
494         const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
495         Material *ma = ps->dm->mat[mp->mat_nr];
496         TexPaintSlot *slot = ma ? ma->texpaintslot + ma->paint_clone_slot : NULL;
497         return slot ? slot->ima : ps->clone_ima;
498 }
499
500 /* fast projection bucket array lookup, use the safe version for bound checking  */
501 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
502 {
503         /* If we were not dealing with screenspace 2D coords we could simple do...
504          * ps->bucketRect[x + (y*ps->buckets_y)] */
505
506         /* please explain?
507          * projCoSS[0] - ps->screenMin[0]   : zero origin
508          * ... / ps->screen_width           : range from 0.0 to 1.0
509          * ... * ps->buckets_x              : use as a bucket index
510          *
511          * Second multiplication does similar but for vertical offset
512          */
513         return ( (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
514                (((int)(((projCoSS[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
515 }
516
517 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
518 {
519         int bucket_index = project_bucket_offset(ps, projCoSS);
520
521         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
522                 return -1;
523         }
524         else {
525                 return bucket_index;
526         }
527 }
528
529 static float VecZDepthOrtho(
530         const float pt[2],
531         const float v1[3], const float v2[3], const float v3[3],
532         float w[3])
533 {
534         barycentric_weights_v2(v1, v2, v3, pt, w);
535         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
536 }
537
538 static float VecZDepthPersp(
539         const float pt[2],
540         const float v1[4], const float v2[4], const float v3[4],
541         float w[3])
542 {
543         float wtot_inv, wtot;
544         float w_tmp[3];
545
546         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
547         /* for the depth we need the weights to match what
548          * barycentric_weights_v2 would return, in this case its easiest just to
549          * undo the 4th axis division and make it unit-sum
550          *
551          * don't call barycentric_weights_v2() because our callers expect 'w'
552          * to be weighted from the perspective */
553         w_tmp[0] = w[0] * v1[3];
554         w_tmp[1] = w[1] * v2[3];
555         w_tmp[2] = w[2] * v3[3];
556
557         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
558
559         if (wtot != 0.0f) {
560                 wtot_inv = 1.0f / wtot;
561
562                 w_tmp[0] = w_tmp[0] * wtot_inv;
563                 w_tmp[1] = w_tmp[1] * wtot_inv;
564                 w_tmp[2] = w_tmp[2] * wtot_inv;
565         }
566         else /* dummy values for zero area face */
567                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
568         /* done mimicing barycentric_weights_v2() */
569
570         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
571 }
572
573
574 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
575 static int project_paint_PickFace(
576         const ProjPaintState *ps, const float pt[2],
577         float w[3])
578 {
579         LinkNode *node;
580         float w_tmp[3];
581         int bucket_index;
582         int best_tri_index = -1;
583         float z_depth_best = FLT_MAX, z_depth;
584
585         bucket_index = project_bucket_offset_safe(ps, pt);
586         if (bucket_index == -1)
587                 return -1;
588
589
590
591         /* we could return 0 for 1 face buckets, as long as this function assumes
592          * that the point its testing is only every originated from an existing face */
593
594         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
595                 const int tri_index = GET_INT_FROM_POINTER(node->link);
596                 const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
597                 const float *vtri_ss[3] = {
598                     ps->screenCoords[ps->dm_mloop[lt->tri[0]].v],
599                     ps->screenCoords[ps->dm_mloop[lt->tri[1]].v],
600                     ps->screenCoords[ps->dm_mloop[lt->tri[2]].v],
601                 };
602
603
604                 if (isect_point_tri_v2(pt, UNPACK3(vtri_ss))) {
605                         if (ps->is_ortho) {
606                                 z_depth = VecZDepthOrtho(pt, UNPACK3(vtri_ss), w_tmp);
607                         }
608                         else {
609                                 z_depth = VecZDepthPersp(pt, UNPACK3(vtri_ss), w_tmp);
610                         }
611
612                         if (z_depth < z_depth_best) {
613                                 best_tri_index = tri_index;
614                                 z_depth_best = z_depth;
615                                 copy_v3_v3(w, w_tmp);
616                         }
617                 }
618         }
619
620         return best_tri_index; /* will be -1 or a valid face */
621 }
622
623 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
624 static void uvco_to_wrapped_pxco(const float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
625 {
626         /* use */
627         *x = fmodf(uv[0], 1.0f);
628         *y = fmodf(uv[1], 1.0f);
629
630         if (*x < 0.0f) *x += 1.0f;
631         if (*y < 0.0f) *y += 1.0f;
632
633         *x = *x * ibuf_x - 0.5f;
634         *y = *y * ibuf_y - 0.5f;
635 }
636
637 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
638 static bool project_paint_PickColor(
639         const ProjPaintState *ps, const float pt[2],
640         float *rgba_fp, unsigned char *rgba, const bool interp)
641 {
642         const MLoopTri *lt;
643         const float *lt_tri_uv[3];
644         float w[3], uv[2];
645         int tri_index;
646         Image *ima;
647         ImBuf *ibuf;
648         int xi, yi;
649
650         tri_index = project_paint_PickFace(ps, pt, w);
651
652         if (tri_index == -1)
653                 return 0;
654
655         lt = &ps->dm_mlooptri[tri_index];
656         PS_LOOPTRI_ASSIGN_UV_3(lt_tri_uv, ps->dm_mloopuv, lt);
657
658         interp_v2_v2v2v2(uv, UNPACK3(lt_tri_uv), w);
659
660         ima = project_paint_face_paint_image(ps, tri_index);
661         ibuf = BKE_image_get_first_ibuf(ima); /* we must have got the imbuf before getting here */
662         if (!ibuf) return 0;
663
664         if (interp) {
665                 float x, y;
666                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
667
668                 if (ibuf->rect_float) {
669                         if (rgba_fp) {
670                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
671                         }
672                         else {
673                                 float rgba_tmp_f[4];
674                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
675                                 premul_float_to_straight_uchar(rgba, rgba_tmp_f);
676                         }
677                 }
678                 else {
679                         if (rgba) {
680                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
681                         }
682                         else {
683                                 unsigned char rgba_tmp[4];
684                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
685                                 straight_uchar_to_premul_float(rgba_fp, rgba_tmp);
686                         }
687                 }
688         }
689         else {
690                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
691                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
692                 //if (xi < 0 || xi >= ibuf->x  ||  yi < 0 || yi >= ibuf->y) return 0;
693
694                 /* wrap */
695                 xi = mod_i((int)(uv[0] * ibuf->x), ibuf->x);
696                 yi = mod_i((int)(uv[1] * ibuf->y), ibuf->y);
697
698                 if (rgba) {
699                         if (ibuf->rect_float) {
700                                 const float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
701                                 premul_float_to_straight_uchar(rgba, rgba_tmp_fp);
702                         }
703                         else {
704                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
705                         }
706                 }
707
708                 if (rgba_fp) {
709                         if (ibuf->rect_float) {
710                                 copy_v4_v4(rgba_fp, (ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
711                         }
712                         else {
713                                 unsigned char *tmp_ch = ((unsigned char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
714                                 straight_uchar_to_premul_float(rgba_fp, tmp_ch);
715                         }
716                 }
717         }
718         BKE_image_release_ibuf(ima, ibuf, NULL);
719         return 1;
720 }
721
722 /**
723  * Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusion test)
724  * \return
725  * -  `0`:   no occlusion
726  * - `-1`: no occlusion but 2D intersection is true
727  * -  `1`: occluded
728  * -  `2`: occluded with `w[3]` weights set (need to know in some cases)
729  */
730 static int project_paint_occlude_ptv(
731         const float pt[3],
732         const float v1[4], const float v2[4], const float v3[4],
733         float w[3], const bool is_ortho)
734 {
735         /* if all are behind us, return false */
736         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
737                 return 0;
738
739         /* do a 2D point in try intersection */
740         if (!isect_point_tri_v2(pt, v1, v2, v3))
741                 return 0;  /* we know there is  */
742
743
744         /* From here on we know there IS an intersection */
745         /* if ALL of the verts are infront of us then we know it intersects ? */
746         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
747                 return 1;
748         }
749         else {
750                 /* we intersect? - find the exact depth at the point of intersection */
751                 /* Is this point is occluded by another face? */
752                 if (is_ortho) {
753                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
754                 }
755                 else {
756                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
757                 }
758         }
759         return -1;
760 }
761
762
763 static int project_paint_occlude_ptv_clip(
764         const float pt[3],
765         const float v1[4], const float v2[4], const float v3[4],
766         const float v1_3d[3], const float v2_3d[3], const float v3_3d[3],
767         float w[3], const bool is_ortho, RegionView3D *rv3d)
768 {
769         float wco[3];
770         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, is_ortho);
771
772         if (ret <= 0)
773                 return ret;
774
775         if (ret == 1) { /* weights not calculated */
776                 if (is_ortho) {
777                         barycentric_weights_v2(v1, v2, v3, pt, w);
778                 }
779                 else {
780                         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
781                 }
782         }
783
784         /* Test if we're in the clipped area, */
785         interp_v3_v3v3v3(wco, v1_3d, v2_3d, v3_3d, w);
786
787         if (!ED_view3d_clipping_test(rv3d, wco, true)) {
788                 return 1;
789         }
790
791         return -1;
792 }
793
794
795 /* Check if a screenspace location is occluded by any other faces
796  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
797  * and doesn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
798 static bool project_bucket_point_occluded(
799         const ProjPaintState *ps, LinkNode *bucketFace,
800         const int orig_face, const float pixelScreenCo[4])
801 {
802         int isect_ret;
803         const bool do_clip = ps->rv3d ? (ps->rv3d->rflag & RV3D_CLIPPING) != 0 : 0;
804
805         /* we could return 0 for 1 face buckets, as long as this function assumes
806          * that the point its testing is only every originated from an existing face */
807
808         for (; bucketFace; bucketFace = bucketFace->next) {
809                 const int tri_index = GET_INT_FROM_POINTER(bucketFace->link);
810
811                 if (orig_face != tri_index) {
812                         const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
813                         const float *vtri_ss[3] = {
814                             ps->screenCoords[ps->dm_mloop[lt->tri[0]].v],
815                             ps->screenCoords[ps->dm_mloop[lt->tri[1]].v],
816                             ps->screenCoords[ps->dm_mloop[lt->tri[2]].v],
817                         };
818                         float w[3];
819
820                         if (do_clip) {
821                                 const float *vtri_co[3] = {
822                                     ps->dm_mvert[ps->dm_mloop[lt->tri[0]].v].co,
823                                     ps->dm_mvert[ps->dm_mloop[lt->tri[1]].v].co,
824                                     ps->dm_mvert[ps->dm_mloop[lt->tri[2]].v].co,
825                                 };
826                                 isect_ret = project_paint_occlude_ptv_clip(
827                                         pixelScreenCo, UNPACK3(vtri_ss), UNPACK3(vtri_co),
828                                         w, ps->is_ortho, ps->rv3d);
829                         }
830                         else {
831                                 isect_ret = project_paint_occlude_ptv(
832                                         pixelScreenCo, UNPACK3(vtri_ss),
833                                         w, ps->is_ortho);
834                         }
835
836                         if (isect_ret >= 1) {
837                                 /* TODO - we may want to cache the first hit,
838                                  * it is not possible to swap the face order in the list anymore */
839                                 return true;
840                         }
841                 }
842         }
843         return false;
844 }
845
846 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
847  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
848 #define ISECT_TRUE 1
849 #define ISECT_TRUE_P1 2
850 #define ISECT_TRUE_P2 3
851 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
852 {
853         float y_diff;
854
855         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
856                 *x_isect = p1[0];
857                 return ISECT_TRUE_P1;
858         }
859         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
860                 *x_isect = p2[0];
861                 return ISECT_TRUE_P2;
862         }
863
864         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
865
866         if (y_diff < 0.000001f) {
867                 *x_isect = (p1[0] + p2[0]) * 0.5f;
868                 return ISECT_TRUE;
869         }
870
871         if (p1[1] > y_level && p2[1] < y_level) {
872                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /* (p1[1] - p2[1]); */
873                 return ISECT_TRUE;
874         }
875         else if (p1[1] < y_level && p2[1] > y_level) {
876                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /* (p2[1] - p1[1]); */
877                 return ISECT_TRUE;
878         }
879         else {
880                 return 0;
881         }
882 }
883
884 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
885 {
886         float x_diff;
887
888         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
889                 *y_isect = p1[1];
890                 return ISECT_TRUE_P1;
891         }
892         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
893                 *y_isect = p2[1];
894                 return ISECT_TRUE_P2;
895         }
896
897         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
898
899         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
900                 *y_isect = (p1[0] + p2[0]) * 0.5f;
901                 return ISECT_TRUE;
902         }
903
904         if (p1[0] > x_level && p2[0] < x_level) {
905                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff;  /* (p1[0] - p2[0]); */
906                 return ISECT_TRUE;
907         }
908         else if (p1[0] < x_level && p2[0] > x_level) {
909                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff;  /* (p2[0] - p1[0]); */
910                 return ISECT_TRUE;
911         }
912         else {
913                 return 0;
914         }
915 }
916
917 /* simple func use for comparing UV locations to check if there are seams.
918  * Its possible this gives incorrect results, when the UVs for 1 face go into the next
919  * tile, but do not do this for the adjacent face, it could return a false positive.
920  * This is so unlikely that Id not worry about it. */
921 #ifndef PROJ_DEBUG_NOSEAMBLEED
922 static bool cmp_uv(const float vec2a[2], const float vec2b[2])
923 {
924         /* if the UV's are not between 0.0 and 1.0 */
925         float xa = fmodf(vec2a[0], 1.0f);
926         float ya = fmodf(vec2a[1], 1.0f);
927
928         float xb = fmodf(vec2b[0], 1.0f);
929         float yb = fmodf(vec2b[1], 1.0f);
930
931         if (xa < 0.0f) xa += 1.0f;
932         if (ya < 0.0f) ya += 1.0f;
933
934         if (xb < 0.0f) xb += 1.0f;
935         if (yb < 0.0f) yb += 1.0f;
936
937         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
938 }
939 #endif
940
941 /* set min_px and max_px to the image space bounds of the UV coords
942  * return zero if there is no area in the returned rectangle */
943 #ifndef PROJ_DEBUG_NOSEAMBLEED
944 static bool pixel_bounds_uv(
945         const float uv_quad[4][2],
946         rcti *bounds_px,
947         const int ibuf_x, const int ibuf_y
948         )
949 {
950         float min_uv[2], max_uv[2]; /* UV bounds */
951
952         INIT_MINMAX2(min_uv, max_uv);
953
954         minmax_v2v2_v2(min_uv, max_uv, uv_quad[0]);
955         minmax_v2v2_v2(min_uv, max_uv, uv_quad[1]);
956         minmax_v2v2_v2(min_uv, max_uv, uv_quad[2]);
957         minmax_v2v2_v2(min_uv, max_uv, uv_quad[3]);
958
959         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
960         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
961
962         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
963         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
964
965         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
966
967         /* face uses no UV area when quantized to pixels? */
968         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
969 }
970 #endif
971
972 static bool pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
973 {
974         float min_uv[2], max_uv[2]; /* UV bounds */
975
976         if (tot == 0) {
977                 return 0;
978         }
979
980         INIT_MINMAX2(min_uv, max_uv);
981
982         while (tot--) {
983                 minmax_v2v2_v2(min_uv, max_uv, (*uv));
984                 uv++;
985         }
986
987         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
988         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
989
990         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
991         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
992
993         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
994
995         /* face uses no UV area when quantized to pixels? */
996         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
997 }
998
999 #ifndef PROJ_DEBUG_NOSEAMBLEED
1000
1001 static void project_face_winding_init(const ProjPaintState *ps, const int tri_index)
1002 {
1003         /* detect the winding of faces in uv space */
1004         const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
1005         const float *lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv, lt) };
1006         float winding = cross_tri_v2(lt_tri_uv[0], lt_tri_uv[1], lt_tri_uv[2]);
1007
1008         if (winding > 0)
1009                 ps->faceWindingFlags[tri_index] |= PROJ_FACE_WINDING_CW;
1010
1011         ps->faceWindingFlags[tri_index] |= PROJ_FACE_WINDING_INIT;
1012 }
1013
1014 /* This function returns 1 if this face has a seam along the 2 face-vert indices
1015  * 'orig_i1_fidx' and 'orig_i2_fidx' */
1016 static bool check_seam(
1017         const ProjPaintState *ps,
1018         const int orig_face, const int orig_i1_fidx, const int orig_i2_fidx,
1019         int *other_face, int *orig_fidx)
1020 {
1021         const MLoopTri *orig_lt = &ps->dm_mlooptri[orig_face];
1022         const float *orig_lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv, orig_lt) };
1023         /* vert indices from face vert order indices */
1024         const unsigned int i1 = ps->dm_mloop[orig_lt->tri[orig_i1_fidx]].v;
1025         const unsigned int i2 = ps->dm_mloop[orig_lt->tri[orig_i2_fidx]].v;
1026         LinkNode *node;
1027         int i1_fidx = -1, i2_fidx = -1; /* index in face */
1028
1029         for (node = ps->vertFaces[i1]; node; node = node->next) {
1030                 const int tri_index = GET_INT_FROM_POINTER(node->link);
1031
1032                 if (tri_index != orig_face) {
1033                         const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
1034                         const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
1035                         /* could check if the 2 faces images match here,
1036                          * but then there wouldn't be a way to return the opposite face's info */
1037
1038
1039                         /* We need to know the order of the verts in the adjacent face
1040                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
1041                         i1_fidx = BKE_MESH_TESSTRI_VINDEX_ORDER(lt_vtri, i1);
1042                         i2_fidx = BKE_MESH_TESSTRI_VINDEX_ORDER(lt_vtri, i2);
1043
1044                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
1045                         if (i2_fidx != -1) {
1046                                 const float *lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv, lt) };
1047                                 Image *tpage = project_paint_face_paint_image(ps, tri_index);
1048                                 Image *orig_tpage = project_paint_face_paint_image(ps, orig_face);
1049
1050                                 BLI_assert(i1_fidx != -1);
1051
1052                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
1053
1054                                 /* set up the other face */
1055                                 *other_face = tri_index;
1056                                 
1057                                 /* we check if difference is 1 here, else we might have a case of edge 2-0 for a tri */
1058                                 *orig_fidx = (i1_fidx < i2_fidx && (i2_fidx - i1_fidx == 1)) ? i1_fidx : i2_fidx;
1059
1060                                 /* initialize face winding if needed */
1061                                 if ((ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_INIT) == 0)
1062                                         project_face_winding_init(ps, tri_index);
1063
1064                                 /* first test if they have the same image */
1065                                 if ((orig_tpage == tpage) &&
1066                                     cmp_uv(orig_lt_tri_uv[orig_i1_fidx], lt_tri_uv[i1_fidx]) &&
1067                                     cmp_uv(orig_lt_tri_uv[orig_i2_fidx], lt_tri_uv[i2_fidx]))
1068                                 {
1069                                         /* if faces don't have the same winding in uv space,
1070                                          * they are on the same side so edge is boundary */
1071                                         if ((ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_CW) !=
1072                                             (ps->faceWindingFlags[orig_face] & PROJ_FACE_WINDING_CW))
1073                                         {
1074                                                 return 1;
1075                                         }
1076
1077                                         // printf("SEAM (NONE)\n");
1078                                         return 0;
1079
1080                                 }
1081                                 else {
1082                                         // printf("SEAM (UV GAP)\n");
1083                                         return 1;
1084                                 }
1085                         }
1086                 }
1087         }
1088         // printf("SEAM (NO FACE)\n");
1089         *other_face = -1;
1090         return 1;
1091 }
1092
1093 #define SMALL_NUMBER  1.e-6f
1094 BLI_INLINE float shell_v2v2_normal_dir_to_dist(float n[2], float d[2])
1095 {
1096         const float angle_cos = (normalize_v2(n) < SMALL_NUMBER) ? fabsf(dot_v2v2(d, n)) : 0.0f;
1097         return (UNLIKELY(angle_cos < SMALL_NUMBER)) ? 1.0f : (1.0f / angle_cos);
1098 }
1099 #undef SMALL_NUMBER
1100
1101 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
1102  * since the outset coords are a margin that keep an even distance from the original UV's,
1103  * note that the image aspect is taken into account */
1104 static void uv_image_outset(
1105         float (*orig_uv)[2], float (*outset_uv)[2], const float scaler,
1106         const int ibuf_x, const int ibuf_y, const bool cw)
1107 {
1108         /* disallow shell-thickness to outset extreme values,
1109          * otherwise near zero area UV's may extend thousands of pixels. */
1110         const float scale_clamp = 5.0f;
1111
1112         float a1, a2, a3;
1113         float puv[3][2]; /* pixelspace uv's */
1114         float no1[2], no2[2], no3[2]; /* normals */
1115         float dir1[2], dir2[2], dir3[2];
1116         float ibuf_inv[2];
1117
1118         ibuf_inv[0] = 1.0f / (float)ibuf_x;
1119         ibuf_inv[1] = 1.0f / (float)ibuf_y;
1120
1121         /* make UV's in pixel space so we can */
1122         puv[0][0] = orig_uv[0][0] * ibuf_x;
1123         puv[0][1] = orig_uv[0][1] * ibuf_y;
1124
1125         puv[1][0] = orig_uv[1][0] * ibuf_x;
1126         puv[1][1] = orig_uv[1][1] * ibuf_y;
1127
1128         puv[2][0] = orig_uv[2][0] * ibuf_x;
1129         puv[2][1] = orig_uv[2][1] * ibuf_y;
1130
1131         /* face edge directions */
1132         sub_v2_v2v2(dir1, puv[1], puv[0]);
1133         sub_v2_v2v2(dir2, puv[2], puv[1]);
1134         sub_v2_v2v2(dir3, puv[0], puv[2]);
1135         normalize_v2(dir1);
1136         normalize_v2(dir2);
1137         normalize_v2(dir3);
1138
1139         /* here we just use the orthonormality property (a1, a2) dot (a2, -a1) = 0
1140          * to get normals from the edge directions based on the winding */
1141         if (cw) {
1142                 no1[0] = -dir3[1] - dir1[1];
1143                 no1[1] =  dir3[0] + dir1[0];
1144                 no2[0] = -dir1[1] - dir2[1];
1145                 no2[1] =  dir1[0] + dir2[0];
1146                 no3[0] = -dir2[1] - dir3[1];
1147                 no3[1] =  dir2[0] + dir3[0];
1148         }
1149         else {
1150                 no1[0] =  dir3[1] + dir1[1];
1151                 no1[1] = -dir3[0] - dir1[0];
1152                 no2[0] =  dir1[1] + dir2[1];
1153                 no2[1] = -dir1[0] - dir2[0];
1154                 no3[0] =  dir2[1] + dir3[1];
1155                 no3[1] = -dir2[0] - dir3[0];
1156         }
1157
1158         a1 = shell_v2v2_normal_dir_to_dist(no1, dir3);
1159         a2 = shell_v2v2_normal_dir_to_dist(no2, dir1);
1160         a3 = shell_v2v2_normal_dir_to_dist(no3, dir2);
1161
1162         CLAMP_MAX(a1, scale_clamp);
1163         CLAMP_MAX(a2, scale_clamp);
1164         CLAMP_MAX(a3, scale_clamp);
1165
1166         mul_v2_fl(no1, a1 * scaler);
1167         mul_v2_fl(no2, a2 * scaler);
1168         mul_v2_fl(no3, a3 * scaler);
1169         add_v2_v2v2(outset_uv[0], puv[0], no1);
1170         add_v2_v2v2(outset_uv[1], puv[1], no2);
1171         add_v2_v2v2(outset_uv[2], puv[2], no3);
1172
1173         mul_v2_v2(outset_uv[0], ibuf_inv);
1174         mul_v2_v2(outset_uv[1], ibuf_inv);
1175         mul_v2_v2(outset_uv[2], ibuf_inv);
1176 }
1177
1178 /*
1179  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1180  * 1<<i - where i is (0-3)
1181  *
1182  * If we're multithreadng, make sure threads are locked when this is called
1183  */
1184 static void project_face_seams_init(const ProjPaintState *ps, const int tri_index)
1185 {
1186         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1187         int fidx1 = 2;
1188         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 */
1189
1190         /* initialize face winding if needed */
1191         if ((ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_INIT) == 0)
1192                 project_face_winding_init(ps, tri_index);
1193
1194         do {
1195                 if ((ps->faceSeamFlags[tri_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1196                         if (check_seam(ps, tri_index, fidx1, fidx2, &other_face, &other_fidx)) {
1197                                 ps->faceSeamFlags[tri_index] |= 1 << fidx1;
1198                                 if (other_face != -1)
1199                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1200                         }
1201                         else {
1202                                 ps->faceSeamFlags[tri_index] |= 16 << fidx1;
1203                                 if (other_face != -1)
1204                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1205                         }
1206                 }
1207
1208                 fidx2 = fidx1;
1209         } while (fidx1--);
1210 }
1211 #endif // PROJ_DEBUG_NOSEAMBLEED
1212
1213
1214 /* Converts a UV location to a 3D screenspace location
1215  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1216  *
1217  * This is used for finding a pixels location in screenspace for painting */
1218 static void screen_px_from_ortho(
1219         const float uv[2],
1220         const float v1co[3], const float v2co[3], const float v3co[3],  /* Screenspace coords */
1221         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1222         float pixelScreenCo[4],
1223         float w[3])
1224 {
1225         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1226         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1227 }
1228
1229 /* same as screen_px_from_ortho except we
1230  * do perspective correction on the pixel coordinate */
1231 static void screen_px_from_persp(
1232         const float uv[2],
1233         const float v1co[4], const float v2co[4], const float v3co[4],  /* screenspace coords */
1234         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1235         float pixelScreenCo[4],
1236         float w[3])
1237 {
1238         float w_int[3];
1239         float wtot_inv, wtot;
1240         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1241
1242         /* re-weight from the 4th coord of each screen vert */
1243         w_int[0] = w[0] * v1co[3];
1244         w_int[1] = w[1] * v2co[3];
1245         w_int[2] = w[2] * v3co[3];
1246
1247         wtot = w_int[0] + w_int[1] + w_int[2];
1248
1249         if (wtot > 0.0f) {
1250                 wtot_inv = 1.0f / wtot;
1251                 w_int[0] *= wtot_inv;
1252                 w_int[1] *= wtot_inv;
1253                 w_int[2] *= wtot_inv;
1254         }
1255         else {
1256                 w[0] = w[1] = w[2] =
1257                 w_int[0] = w_int[1] = w_int[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1258         }
1259         /* done re-weighting */
1260
1261         /* do interpolation based on projected weight */
1262         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w_int);
1263 }
1264
1265
1266 /**
1267  * Set a direction vector based on a screen location.
1268  * (use for perspective view, else we can simply use `ps->viewDir`)
1269  *
1270  * Similar functionality to #ED_view3d_win_to_vector
1271  *
1272  * \param r_dir: Resulting direction (length is undefined).
1273  */
1274 static void screen_px_to_vector_persp(
1275         int winx, int winy, const float projmat_inv[4][4], const float view_pos[3],
1276         const float co_px[2],
1277         float r_dir[3])
1278 {
1279         r_dir[0] = 2.0f * (co_px[0] / winx) - 1.0f;
1280         r_dir[1] = 2.0f * (co_px[1] / winy) - 1.0f;
1281         r_dir[2] = -0.5f;
1282         mul_project_m4_v3((float(*)[4])projmat_inv, r_dir);
1283         sub_v3_v3(r_dir, view_pos);
1284 }
1285
1286 /**
1287  * Special function to return the factor to a point along a line in pixel space.
1288  *
1289  * This is needed since we can't use #line_point_factor_v2 for perspective screen-space coords.
1290  *
1291  * \param p: 2D screen-space location.
1292  * \param v1, v2: 3D object-space locations.
1293  */
1294 static float screen_px_line_point_factor_v2_persp(
1295         const ProjPaintState *ps,
1296         const float p[2],
1297         const float v1[3], const float v2[3])
1298 {
1299         const float zero[3] = {0};
1300         float v1_proj[3], v2_proj[3];
1301         float dir[3];
1302
1303         screen_px_to_vector_persp(ps->winx, ps->winy, ps->projectMatInv, ps->viewPos, p, dir);
1304
1305         sub_v3_v3v3(v1_proj, v1, ps->viewPos);
1306         sub_v3_v3v3(v2_proj, v2, ps->viewPos);
1307
1308         project_plane_v3_v3v3(v1_proj, v1_proj, dir);
1309         project_plane_v3_v3v3(v2_proj, v2_proj, dir);
1310
1311         return line_point_factor_v2(zero, v1_proj, v2_proj);
1312 }
1313
1314
1315 static void project_face_pixel(
1316         const float *lt_tri_uv[3], ImBuf *ibuf_other, const float w[3],
1317         unsigned char rgba_ub[4], float rgba_f[4])
1318 {
1319         float uv_other[2], x, y;
1320
1321         interp_v2_v2v2v2(uv_other, UNPACK3(lt_tri_uv), w);
1322
1323         /* use */
1324         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1325
1326         if (ibuf_other->rect_float) { /* from float to float */
1327                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1328         }
1329         else { /* from char to float */
1330                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1331         }
1332
1333 }
1334
1335 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1336 static float project_paint_uvpixel_mask(
1337         const ProjPaintState *ps,
1338         const int tri_index,
1339         const float w[3])
1340 {
1341         float mask;
1342
1343         /* Image Mask */
1344         if (ps->do_layer_stencil) {
1345                 /* another UV maps image is masking this one's */
1346                 ImBuf *ibuf_other;
1347                 Image *other_tpage = ps->stencil_ima;
1348
1349                 if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1350                         const MLoopTri *lt_other = &ps->dm_mlooptri[tri_index];
1351                         const float *lt_other_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv, lt_other) };
1352
1353                         /* BKE_image_acquire_ibuf - TODO - this may be slow */
1354                         unsigned char rgba_ub[4];
1355                         float rgba_f[4];
1356
1357                         project_face_pixel(lt_other_tri_uv, ibuf_other, w, rgba_ub, rgba_f);
1358
1359                         if (ibuf_other->rect_float) { /* from float to float */
1360                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) * (1.0f / 3.0f)) * rgba_f[3];
1361                         }
1362                         else { /* from char to float */
1363                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) * (1.0f / (255.0f * 3.0f))) * (rgba_ub[3] * (1.0f / 255.0f));
1364                         }
1365
1366                         BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1367
1368                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1369                                 mask = (1.0f - mask);
1370
1371                         if (mask == 0.0f) {
1372                                 return 0.0f;
1373                         }
1374                 }
1375                 else {
1376                         return 0.0f;
1377                 }
1378         }
1379         else {
1380                 mask = 1.0f;
1381         }
1382
1383         if (ps->do_mask_cavity) {
1384                 const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
1385                 const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
1386                 float ca1, ca2, ca3, ca_mask;
1387                 ca1 = ps->cavities[lt_vtri[0]];
1388                 ca2 = ps->cavities[lt_vtri[1]];
1389                 ca3 = ps->cavities[lt_vtri[2]];
1390
1391                 ca_mask = w[0] * ca1 + w[1] * ca2 + w[2] * ca3;
1392                 ca_mask = curvemapping_evaluateF(ps->cavity_curve, 0, ca_mask);
1393                 CLAMP(ca_mask, 0.0f, 1.0f);
1394                 mask *= ca_mask;
1395         }
1396
1397         /* calculate mask */
1398         if (ps->do_mask_normal) {
1399                 const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
1400                 const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
1401                 const MPoly *mp = &ps->dm_mpoly[lt->poly];
1402                 float no[3], angle_cos;
1403
1404                 if (mp->flag & ME_SMOOTH) {
1405                         const short *no1, *no2, *no3;
1406                         no1 = ps->dm_mvert[lt_vtri[0]].no;
1407                         no2 = ps->dm_mvert[lt_vtri[1]].no;
1408                         no3 = ps->dm_mvert[lt_vtri[2]].no;
1409
1410                         no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1411                         no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1412                         no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1413                         normalize_v3(no);
1414                 }
1415                 else {
1416                         /* incase the */
1417 #if 1
1418                         /* normalizing per pixel isn't optimal, we could cache or check ps->*/
1419                         normal_tri_v3(no,
1420                                       ps->dm_mvert[lt_vtri[0]].co,
1421                                       ps->dm_mvert[lt_vtri[1]].co,
1422                                       ps->dm_mvert[lt_vtri[2]].co);
1423 #else
1424                         /* don't use because some modifiers dont have normal data (subsurf for eg) */
1425                         copy_v3_v3(no, (float *)ps->dm->getTessFaceData(ps->dm, tri_index, CD_NORMAL));
1426 #endif
1427                 }
1428
1429                 if (UNLIKELY(ps->is_flip_object)) {
1430                         negate_v3(no);
1431                 }
1432
1433                 /* now we can use the normal as a mask */
1434                 if (ps->is_ortho) {
1435                         angle_cos = dot_v3v3(ps->viewDir, no);
1436                 }
1437                 else {
1438                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1439                         float viewDirPersp[3];
1440                         const float *co1, *co2, *co3;
1441                         co1 = ps->dm_mvert[lt_vtri[0]].co;
1442                         co2 = ps->dm_mvert[lt_vtri[1]].co;
1443                         co3 = ps->dm_mvert[lt_vtri[2]].co;
1444
1445                         /* Get the direction from the viewPoint to the pixel and normalize */
1446                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1447                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1448                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1449                         normalize_v3(viewDirPersp);
1450                         if (UNLIKELY(ps->is_flip_object)) {
1451                                 negate_v3(viewDirPersp);
1452                         }
1453
1454                         angle_cos = dot_v3v3(viewDirPersp, no);
1455                 }
1456
1457                 if (angle_cos <= ps->normal_angle__cos) {
1458                         return 0.0f; /* outsize the normal limit*/
1459                 }
1460                 else if (angle_cos < ps->normal_angle_inner__cos) {
1461                         mask *= (ps->normal_angle - acosf(angle_cos)) / ps->normal_angle_range;
1462                 } /* otherwise no mask normal is needed, were within the limit */
1463         }
1464
1465         /* This only works when the opacity dosnt change while painting, stylus pressure messes with this
1466          * so don't use it. */
1467         // if (ps->is_airbrush == 0) mask *= BKE_brush_alpha_get(ps->brush);
1468
1469         return mask;
1470 }
1471
1472 static int project_paint_pixel_sizeof(const short tool)
1473 {
1474         if ((tool == PAINT_TOOL_CLONE) || (tool == PAINT_TOOL_SMEAR)) {
1475                 return sizeof(ProjPixelClone);
1476         }
1477         else {
1478                 return sizeof(ProjPixel);
1479         }
1480 }
1481
1482 static int project_paint_undo_subtiles(const TileInfo *tinf, int tx, int ty)
1483 {
1484         ProjPaintImage *pjIma = tinf->pjima;
1485         int tile_index = tx + ty * tinf->tile_width;
1486         bool generate_tile = false;
1487
1488         /* double check lock to avoid locking */
1489         if (UNLIKELY(!pjIma->undoRect[tile_index])) {
1490                 if (tinf->lock)
1491                         BLI_spin_lock(tinf->lock);
1492                 if (LIKELY(!pjIma->undoRect[tile_index])) {
1493                         pjIma->undoRect[tile_index] = TILE_PENDING;
1494                         generate_tile = true;
1495                 }
1496                 if (tinf->lock)
1497                         BLI_spin_unlock(tinf->lock);
1498         }
1499
1500
1501         if (generate_tile) {
1502                 volatile void *undorect;
1503                 if (tinf->masked) {
1504                         undorect = image_undo_push_tile(
1505                                 pjIma->ima, pjIma->ibuf, tinf->tmpibuf,
1506                                 tx, ty, &pjIma->maskRect[tile_index], &pjIma->valid[tile_index], true, false);
1507                 }
1508                 else {
1509                         undorect = image_undo_push_tile(
1510                                 pjIma->ima, pjIma->ibuf, tinf->tmpibuf,
1511                                 tx, ty, NULL, &pjIma->valid[tile_index], true, false);
1512                 }
1513
1514                 pjIma->ibuf->userflags |= IB_BITMAPDIRTY;
1515                 /* tile ready, publish */
1516                 if (tinf->lock)
1517                         BLI_spin_lock(tinf->lock);
1518                 pjIma->undoRect[tile_index] = undorect;
1519                 if (tinf->lock)
1520                         BLI_spin_unlock(tinf->lock);
1521
1522         }
1523
1524         return tile_index;
1525 }
1526
1527 /* run this function when we know a bucket's, face's pixel can be initialized,
1528  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1529 static ProjPixel *project_paint_uvpixel_init(
1530         const ProjPaintState *ps,
1531         MemArena *arena,
1532         const TileInfo *tinf,
1533         int x_px, int y_px,
1534         const float mask,
1535         const int tri_index,
1536         const float pixelScreenCo[4],
1537         const float world_spaceCo[3],
1538         const float w[3])
1539 {
1540         ProjPixel *projPixel;
1541         int x_tile, y_tile;
1542         int x_round, y_round;
1543         int tile_offset;
1544         /* volatile is important here to ensure pending check is not optimized away by compiler*/
1545         volatile int tile_index;
1546
1547         ProjPaintImage *projima = tinf->pjima;
1548         ImBuf *ibuf = projima->ibuf;
1549         /* wrap pixel location */
1550
1551         x_px = mod_i(x_px, ibuf->x);
1552         y_px = mod_i(y_px, ibuf->y);
1553
1554         BLI_assert(ps->pixel_sizeof == project_paint_pixel_sizeof(ps->tool));
1555         projPixel = BLI_memarena_alloc(arena, ps->pixel_sizeof);
1556
1557         /* calculate the undo tile offset of the pixel, used to store the original
1558          * pixel color and accumulated mask if any */
1559         x_tile =  x_px >> IMAPAINT_TILE_BITS;
1560         y_tile =  y_px >> IMAPAINT_TILE_BITS;
1561
1562         x_round = x_tile * IMAPAINT_TILE_SIZE;
1563         y_round = y_tile * IMAPAINT_TILE_SIZE;
1564         //memset(projPixel, 0, size);
1565
1566         tile_offset = (x_px - x_round) + (y_px - y_round) * IMAPAINT_TILE_SIZE;
1567         tile_index = project_paint_undo_subtiles(tinf, x_tile, y_tile);
1568
1569         /* other thread may be initializing the tile so wait here */
1570         while (projima->undoRect[tile_index] == TILE_PENDING)
1571                 ;
1572
1573         BLI_assert(tile_index < (IMAPAINT_TILE_NUMBER(ibuf->x) * IMAPAINT_TILE_NUMBER(ibuf->y)));
1574         BLI_assert(tile_offset < (IMAPAINT_TILE_SIZE * IMAPAINT_TILE_SIZE));
1575
1576         projPixel->valid = projima->valid[tile_index];
1577
1578         if (ibuf->rect_float) {
1579                 projPixel->pixel.f_pt = ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1580                 projPixel->origColor.f_pt = (float *)projima->undoRect[tile_index] + 4 * tile_offset;
1581                 zero_v4(projPixel->newColor.f);
1582         }
1583         else {
1584                 projPixel->pixel.ch_pt = (unsigned char *)(ibuf->rect + (x_px + y_px * ibuf->x));
1585                 projPixel->origColor.uint_pt = (unsigned int *)projima->undoRect[tile_index] + tile_offset;
1586                 projPixel->newColor.uint = 0;
1587         }
1588
1589         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1590         if (ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D) {
1591                 copy_v3_v3(projPixel->worldCoSS, world_spaceCo);
1592         }
1593
1594         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1595
1596         projPixel->x_px = x_px;
1597         projPixel->y_px = y_px;
1598
1599         projPixel->mask = (unsigned short)(mask * 65535);
1600         if (ps->do_masking)
1601                 projPixel->mask_accum = projima->maskRect[tile_index] + tile_offset;
1602         else
1603                 projPixel->mask_accum = NULL;
1604
1605         /* which bounding box cell are we in?, needed for undo */
1606         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1607                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1608
1609         /* done with view3d_project_float inline */
1610         if (ps->tool == PAINT_TOOL_CLONE) {
1611                 if (ps->dm_mloopuv_clone) {
1612                         ImBuf *ibuf_other;
1613                         Image *other_tpage = project_paint_face_clone_image(ps, tri_index);
1614
1615                         if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1616                                 const MLoopTri *lt_other = &ps->dm_mlooptri[tri_index];
1617                                 const float *lt_other_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv_clone, lt_other) };
1618
1619                                 /* BKE_image_acquire_ibuf - TODO - this may be slow */
1620
1621                                 if (ibuf->rect_float) {
1622                                         if (ibuf_other->rect_float) { /* from float to float */
1623                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1624                                         }
1625                                         else { /* from char to float */
1626                                                 unsigned char rgba_ub[4];
1627                                                 float rgba[4];
1628                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, rgba_ub, NULL);
1629                                                 if (ps->use_colormanagement) {
1630                                                         srgb_to_linearrgb_uchar4(rgba, rgba_ub);
1631                                                 }
1632                                                 else {
1633                                                         rgba_uchar_to_float(rgba, rgba_ub);
1634                                                 }
1635                                                 straight_to_premul_v4_v4(((ProjPixelClone *)projPixel)->clonepx.f, rgba);
1636                                         }
1637                                 }
1638                                 else {
1639                                         if (ibuf_other->rect_float) { /* float to char */
1640                                                 float rgba[4];
1641                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, NULL, rgba);
1642                                                 premul_to_straight_v4(rgba);
1643                                                 if (ps->use_colormanagement) {
1644                                                         linearrgb_to_srgb_uchar3(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1645                                                 }
1646                                                 else {
1647                                                         rgb_float_to_uchar(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1648                                                 }
1649                                                 ((ProjPixelClone *)projPixel)->clonepx.ch[3] =  rgba[3] * 255;
1650                                         }
1651                                         else { /* char to char */
1652                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1653                                         }
1654                                 }
1655
1656                                 BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1657                         }
1658                         else {
1659                                 if (ibuf->rect_float) {
1660                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1661                                 }
1662                                 else {
1663                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1664                                 }
1665                         }
1666
1667                 }
1668                 else {
1669                         float co[2];
1670                         sub_v2_v2v2(co, projPixel->projCoSS, ps->cloneOffset);
1671
1672                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1673                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1674                         if (ibuf->rect_float) {
1675                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1676                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1677                                 }
1678                         }
1679                         else {
1680                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1681                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1682                                 }
1683                         }
1684                 }
1685         }
1686
1687 #ifdef PROJ_DEBUG_PAINT
1688         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1689         else                  projPixel->pixel.ch_pt[0] = 0;
1690 #endif
1691         /* pointer arithmetics */
1692         projPixel->image_index = projima - ps->projImages;
1693
1694         return projPixel;
1695 }
1696
1697 static bool line_clip_rect2f(
1698         const rctf *cliprect,
1699         const rctf *rect,
1700         const float l1[2], const float l2[2],
1701         float l1_clip[2], float l2_clip[2])
1702 {
1703         /* first account for horizontal, then vertical lines */
1704         /* horiz */
1705         if (fabsf(l1[1] - l2[1]) < PROJ_PIXEL_TOLERANCE) {
1706                 /* is the line out of range on its Y axis? */
1707                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1708                         return 0;
1709                 }
1710                 /* line is out of range on its X axis */
1711                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1712                         return 0;
1713                 }
1714
1715
1716                 if (fabsf(l1[0] - l2[0]) < PROJ_PIXEL_TOLERANCE) { /* this is a single point  (or close to)*/
1717                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1718                                 copy_v2_v2(l1_clip, l1);
1719                                 copy_v2_v2(l2_clip, l2);
1720                                 return 1;
1721                         }
1722                         else {
1723                                 return 0;
1724                         }
1725                 }
1726
1727                 copy_v2_v2(l1_clip, l1);
1728                 copy_v2_v2(l2_clip, l2);
1729                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1730                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1731                 return 1;
1732         }
1733         else if (fabsf(l1[0] - l2[0]) < PROJ_PIXEL_TOLERANCE) {
1734                 /* is the line out of range on its X axis? */
1735                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1736                         return 0;
1737                 }
1738
1739                 /* line is out of range on its Y axis */
1740                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1741                         return 0;
1742                 }
1743
1744                 if (fabsf(l1[1] - l2[1]) < PROJ_PIXEL_TOLERANCE) { /* this is a single point  (or close to)*/
1745                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1746                                 copy_v2_v2(l1_clip, l1);
1747                                 copy_v2_v2(l2_clip, l2);
1748                                 return 1;
1749                         }
1750                         else {
1751                                 return 0;
1752                         }
1753                 }
1754
1755                 copy_v2_v2(l1_clip, l1);
1756                 copy_v2_v2(l2_clip, l2);
1757                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1758                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1759                 return 1;
1760         }
1761         else {
1762                 float isect;
1763                 short ok1 = 0;
1764                 short ok2 = 0;
1765
1766                 /* Done with vertical lines */
1767
1768                 /* are either of the points inside the rectangle ? */
1769                 if (BLI_rctf_isect_pt_v(rect, l1)) {
1770                         copy_v2_v2(l1_clip, l1);
1771                         ok1 = 1;
1772                 }
1773
1774                 if (BLI_rctf_isect_pt_v(rect, l2)) {
1775                         copy_v2_v2(l2_clip, l2);
1776                         ok2 = 1;
1777                 }
1778
1779                 /* line inside rect */
1780                 if (ok1 && ok2) return 1;
1781
1782                 /* top/bottom */
1783                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= cliprect->xmin) && (isect <= cliprect->xmax)) {
1784                         if (l1[1] < l2[1]) { /* line 1 is outside */
1785                                 l1_clip[0] = isect;
1786                                 l1_clip[1] = rect->ymin;
1787                                 ok1 = 1;
1788                         }
1789                         else {
1790                                 l2_clip[0] = isect;
1791                                 l2_clip[1] = rect->ymin;
1792                                 ok2 = 2;
1793                         }
1794                 }
1795
1796                 if (ok1 && ok2) return 1;
1797
1798                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= cliprect->xmin) && (isect <= cliprect->xmax)) {
1799                         if (l1[1] > l2[1]) { /* line 1 is outside */
1800                                 l1_clip[0] = isect;
1801                                 l1_clip[1] = rect->ymax;
1802                                 ok1 = 1;
1803                         }
1804                         else {
1805                                 l2_clip[0] = isect;
1806                                 l2_clip[1] = rect->ymax;
1807                                 ok2 = 2;
1808                         }
1809                 }
1810
1811                 if (ok1 && ok2) return 1;
1812
1813                 /* left/right */
1814                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= cliprect->ymin) && (isect <= cliprect->ymax)) {
1815                         if (l1[0] < l2[0]) { /* line 1 is outside */
1816                                 l1_clip[0] = rect->xmin;
1817                                 l1_clip[1] = isect;
1818                                 ok1 = 1;
1819                         }
1820                         else {
1821                                 l2_clip[0] = rect->xmin;
1822                                 l2_clip[1] = isect;
1823                                 ok2 = 2;
1824                         }
1825                 }
1826
1827                 if (ok1 && ok2) return 1;
1828
1829                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= cliprect->ymin) && (isect <= cliprect->ymax)) {
1830                         if (l1[0] > l2[0]) { /* line 1 is outside */
1831                                 l1_clip[0] = rect->xmax;
1832                                 l1_clip[1] = isect;
1833                                 ok1 = 1;
1834                         }
1835                         else {
1836                                 l2_clip[0] = rect->xmax;
1837                                 l2_clip[1] = isect;
1838                                 ok2 = 2;
1839                         }
1840                 }
1841
1842                 if (ok1 && ok2) {
1843                         return 1;
1844                 }
1845                 else {
1846                         return 0;
1847                 }
1848         }
1849 }
1850
1851
1852
1853 /**
1854  * Scale the tri about its center
1855  * scaling by #PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1856  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces
1857  */
1858 #ifndef PROJ_DEBUG_NOSEAMBLEED
1859
1860 static void scale_tri(float insetCos[3][3], const float *origCos[4], const float inset)
1861 {
1862         float cent[3];
1863         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) * (1.0f / 3.0f);
1864         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) * (1.0f / 3.0f);
1865         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) * (1.0f / 3.0f);
1866
1867         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1868         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1869         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1870
1871         mul_v3_fl(insetCos[0], inset);
1872         mul_v3_fl(insetCos[1], inset);
1873         mul_v3_fl(insetCos[2], inset);
1874
1875         add_v3_v3(insetCos[0], cent);
1876         add_v3_v3(insetCos[1], cent);
1877         add_v3_v3(insetCos[2], cent);
1878 }
1879 #endif //PROJ_DEBUG_NOSEAMBLEED
1880
1881 static float len_squared_v2v2_alt(const float v1[2], const float v2_1, const float v2_2)
1882 {
1883         float x, y;
1884
1885         x = v1[0] - v2_1;
1886         y = v1[1] - v2_2;
1887         return x * x + y * y;
1888 }
1889
1890 /* note, use a squared value so we can use len_squared_v2v2
1891  * be sure that you have done a bounds check first or this may fail */
1892 /* only give bucket_bounds as an arg because we need it elsewhere */
1893 static bool project_bucket_isect_circle(const float cent[2], const float radius_squared, const rctf *bucket_bounds)
1894 {
1895
1896         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect
1897          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1898          * this is even less work then an intersection test
1899          */
1900 #if 0
1901         if (BLI_rctf_isect_pt_v(bucket_bounds, cent))
1902                 return 1;
1903 #endif
1904
1905         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1906             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1907         {
1908                 return 1;
1909         }
1910
1911         /* out of bounds left */
1912         if (cent[0] < bucket_bounds->xmin) {
1913                 /* lower left out of radius test */
1914                 if (cent[1] < bucket_bounds->ymin) {
1915                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1916                 }
1917                 /* top left test */
1918                 else if (cent[1] > bucket_bounds->ymax) {
1919                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1920                 }
1921         }
1922         else if (cent[0] > bucket_bounds->xmax) {
1923                 /* lower right out of radius test */
1924                 if (cent[1] < bucket_bounds->ymin) {
1925                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1926                 }
1927                 /* top right test */
1928                 else if (cent[1] > bucket_bounds->ymax) {
1929                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1930                 }
1931         }
1932
1933         return 0;
1934 }
1935
1936
1937
1938 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1939  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1940  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1941  * (viewed from the side)
1942  *
1943  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1944  * funcs that only account for points inside the triangle.
1945  * however switching back to this for ortho is always an option */
1946
1947 static void rect_to_uvspace_ortho(
1948         const rctf *bucket_bounds,
1949         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1950         const float *uv1co, const float *uv2co, const float *uv3co,
1951         float bucket_bounds_uv[4][2],
1952         const int flip)
1953 {
1954         float uv[2];
1955         float w[3];
1956
1957         /* get the UV space bounding box */
1958         uv[0] = bucket_bounds->xmax;
1959         uv[1] = bucket_bounds->ymin;
1960         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1961         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1962
1963         //uv[0] = bucket_bounds->xmax; // set above
1964         uv[1] = bucket_bounds->ymax;
1965         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1966         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1967
1968         uv[0] = bucket_bounds->xmin;
1969         //uv[1] = bucket_bounds->ymax; // set above
1970         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1971         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1972
1973         //uv[0] = bucket_bounds->xmin; // set above
1974         uv[1] = bucket_bounds->ymin;
1975         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1976         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1977 }
1978
1979 /* same as above but use barycentric_weights_v2_persp */
1980 static void rect_to_uvspace_persp(
1981         const rctf *bucket_bounds,
1982         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1983         const float *uv1co, const float *uv2co, const float *uv3co,
1984         float bucket_bounds_uv[4][2],
1985         const int flip
1986         )
1987 {
1988         float uv[2];
1989         float w[3];
1990
1991         /* get the UV space bounding box */
1992         uv[0] = bucket_bounds->xmax;
1993         uv[1] = bucket_bounds->ymin;
1994         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1995         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1996
1997         //uv[0] = bucket_bounds->xmax; // set above
1998         uv[1] = bucket_bounds->ymax;
1999         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2000         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
2001
2002         uv[0] = bucket_bounds->xmin;
2003         //uv[1] = bucket_bounds->ymax; // set above
2004         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2005         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
2006
2007         //uv[0] = bucket_bounds->xmin; // set above
2008         uv[1] = bucket_bounds->ymin;
2009         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2010         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
2011 }
2012
2013 /* This works as we need it to but we can save a few steps and not use it */
2014
2015 #if 0
2016 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
2017 {
2018         float v1[2], v2[2];
2019
2020         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
2021         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
2022
2023         return -atan2f(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
2024 }
2025 #endif
2026
2027 #define ISECT_1 (1)
2028 #define ISECT_2 (1 << 1)
2029 #define ISECT_3 (1 << 2)
2030 #define ISECT_4 (1 << 3)
2031 #define ISECT_ALL3 ((1 << 3) - 1)
2032 #define ISECT_ALL4 ((1 << 4) - 1)
2033
2034 /* limit must be a fraction over 1.0f */
2035 static bool IsectPT2Df_limit(
2036         const float pt[2],
2037         const float v1[2], const float v2[2], const float v3[2],
2038         const float limit)
2039 {
2040         return ((area_tri_v2(pt, v1, v2) +
2041                  area_tri_v2(pt, v2, v3) +
2042                  area_tri_v2(pt, v3, v1)) / (area_tri_v2(v1, v2, v3))) < limit;
2043 }
2044
2045 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
2046  * so we have the clipped UV's to do pixel intersection tests with
2047  * */
2048 static int float_z_sort_flip(const void *p1, const void *p2)
2049 {
2050         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
2051 }
2052
2053 static int float_z_sort(const void *p1, const void *p2)
2054 {
2055         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
2056 }
2057
2058 /* assumes one point is within the rectangle */
2059 static bool line_rect_clip(
2060         const rctf *rect,
2061         const float l1[4], const float l2[4],
2062         const float uv1[2], const float uv2[2],
2063         float uv[2], bool is_ortho)
2064 {
2065         float min = FLT_MAX, tmp;
2066         float xlen = l2[0] - l1[0];
2067         float ylen = l2[1] - l1[1];
2068
2069         /* 0.1 might seem too much, but remember, this is pixels! */
2070         if (xlen > 0.1f) {
2071                 if ((l1[0] - rect->xmin) * (l2[0] - rect->xmin) <= 0) {
2072                         tmp = rect->xmin;
2073                         min = min_ff((tmp - l1[0]) / xlen, min);
2074                 }
2075                 else if ((l1[0] - rect->xmax) * (l2[0] - rect->xmax) < 0) {
2076                         tmp = rect->xmax;
2077                         min = min_ff((tmp - l1[0]) / xlen, min);
2078                 }
2079         }
2080
2081         if (ylen > 0.1f) {
2082                 if ((l1[1] - rect->ymin) * (l2[1] - rect->ymin) <= 0) {
2083                         tmp = rect->ymin;
2084                         min = min_ff((tmp - l1[1]) / ylen, min);
2085                 }
2086                 else if ((l1[1] - rect->ymax) * (l2[1] - rect->ymax) < 0) {
2087                         tmp = rect->ymax;
2088                         min = min_ff((tmp - l1[1]) / ylen, min);
2089                 }
2090         }
2091
2092         if (min == FLT_MAX)
2093                 return false;
2094
2095         tmp = (is_ortho) ? 1.0f : (l1[3] + min * (l2[3] - l1[3]));
2096
2097         uv[0] = (uv1[0] + min / tmp * (uv2[0] - uv1[0]));
2098         uv[1] = (uv1[1] + min / tmp * (uv2[1] - uv1[1]));
2099
2100         return true;
2101 }
2102
2103
2104 static void project_bucket_clip_face(
2105         const bool is_ortho, const bool is_flip_object,
2106         const rctf *cliprect,
2107         const rctf *bucket_bounds,
2108         const float *v1coSS, const float *v2coSS, const float *v3coSS,
2109         const float *uv1co, const float *uv2co, const float *uv3co,
2110         float bucket_bounds_uv[8][2],
2111         int *tot, bool cull)
2112 {
2113         int inside_bucket_flag = 0;
2114         int inside_face_flag = 0;
2115         int flip;
2116         bool collinear = false;
2117         
2118         float bucket_bounds_ss[4][2];
2119
2120         /* detect pathological case where face the three vertices are almost collinear in screen space.
2121          * mostly those will be culled but when flood filling or with smooth shading it's a possibility */
2122         if (min_fff(dist_squared_to_line_v2(v1coSS, v2coSS, v3coSS),
2123                     dist_squared_to_line_v2(v2coSS, v3coSS, v1coSS),
2124                     dist_squared_to_line_v2(v3coSS, v1coSS, v2coSS)) < PROJ_PIXEL_TOLERANCE)
2125         {
2126                 collinear = true;
2127         }
2128         
2129         /* get the UV space bounding box */
2130         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v1coSS);
2131         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v2coSS) << 1;
2132         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v3coSS) << 2;
2133         
2134         if (inside_bucket_flag == ISECT_ALL3) {
2135                 /* is_flip_object is used here because we use the face winding */
2136                 flip = (((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != is_flip_object) !=
2137                         (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
2138
2139                 /* all screenspace points are inside the bucket bounding box,
2140                  * this means we don't need to clip and can simply return the UVs */
2141                 if (flip) { /* facing the back? */
2142                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
2143                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2144                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
2145                 }
2146                 else {
2147                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
2148                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2149                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
2150                 }               
2151                 
2152                 *tot = 3;
2153                 return;
2154         }
2155         /* handle pathological case here, no need for further intersections below since tringle area is almost zero */
2156         if (collinear) {
2157                 int flag;
2158                 
2159                 (*tot) = 0;
2160
2161                 if (cull)
2162                         return;
2163                 
2164                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(bucket_bounds_uv[*tot], uv1co); (*tot)++; }
2165
2166                 flag = inside_bucket_flag & (ISECT_1 | ISECT_2);
2167                 if (flag && flag != (ISECT_1 | ISECT_2)) {
2168                         if (line_rect_clip(bucket_bounds, v1coSS, v2coSS, uv1co, uv2co, bucket_bounds_uv[*tot], is_ortho))
2169                                 (*tot)++;
2170                 }
2171                 
2172                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(bucket_bounds_uv[*tot], uv2co); (*tot)++; }
2173                 
2174                 flag = inside_bucket_flag & (ISECT_2 | ISECT_3);
2175                 if (flag && flag != (ISECT_2 | ISECT_3)) {
2176                         if (line_rect_clip(bucket_bounds, v2coSS, v3coSS, uv2co, uv3co, bucket_bounds_uv[*tot], is_ortho))
2177                                 (*tot)++;
2178                 }
2179
2180                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(bucket_bounds_uv[*tot], uv3co); (*tot)++; }
2181
2182                 flag = inside_bucket_flag & (ISECT_3 | ISECT_1);
2183                 if (flag && flag != (ISECT_3 | ISECT_1)) {
2184                         if (line_rect_clip(bucket_bounds, v3coSS, v1coSS, uv3co, uv1co, bucket_bounds_uv[*tot], is_ortho))
2185                                 (*tot)++;
2186                 }
2187                 
2188                 if ((*tot) < 3) {
2189                         /* no intersections to speak of, but more probable is that all face is just outside the
2190                          * rectangle and culled due to float precision issues. Since above tests have failed,
2191                          * just dump triangle as is for painting */
2192                         *tot = 0;
2193                         copy_v2_v2(bucket_bounds_uv[*tot], uv1co); (*tot)++;
2194                         copy_v2_v2(bucket_bounds_uv[*tot], uv2co); (*tot)++;
2195                         copy_v2_v2(bucket_bounds_uv[*tot], uv3co); (*tot)++;
2196                         return;
2197                 }
2198
2199                 return;
2200         }
2201
2202         /* get the UV space bounding box */
2203         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
2204         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
2205         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
2206         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
2207
2208         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
2209         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
2210         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
2211
2212         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
2213         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
2214         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
2215
2216         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
2217         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
2218         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
2219
2220         flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) !=
2221                 (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
2222
2223         if (inside_face_flag == ISECT_ALL4) {
2224                 /* bucket is totally inside the screenspace face, we can safely use weights */
2225
2226                 if (is_ortho) {
2227                         rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2228                 }
2229                 else {
2230                         rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2231                 }
2232
2233                 *tot = 4;
2234                 return;
2235         }
2236         else {
2237                 /* The Complicated Case!
2238                  *
2239                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
2240                  *
2241                  * we need to make a convex polyline from the intersection between the screenspace face
2242                  * and the bucket bounds.
2243                  *
2244                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
2245                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
2246                  * do a correct clipping on both shapes. */
2247
2248
2249                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
2250
2251
2252
2253                 /* Maximum possible 6 intersections when using a rectangle and triangle */
2254                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
2255                 float v1_clipSS[2], v2_clipSS[2];
2256                 float w[3];
2257
2258                 /* calc center */
2259                 float cent[2] = {0.0f, 0.0f};
2260                 /*float up[2] = {0.0f, 1.0f};*/
2261                 int i;
2262                 bool doubles;
2263
2264                 (*tot) = 0;
2265
2266                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
2267                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
2268                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
2269                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
2270
2271                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
2272                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
2273                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
2274
2275                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
2276                         if (line_clip_rect2f(cliprect, bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
2277                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2278                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2279                         }
2280                 }
2281
2282                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
2283                         if (line_clip_rect2f(cliprect, bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
2284                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2285                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2286                         }
2287                 }
2288
2289                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
2290                         if (line_clip_rect2f(cliprect, bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
2291                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2292                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2293                         }
2294                 }
2295
2296
2297                 if ((*tot) < 3) { /* no intersections to speak of */
2298                         *tot = 0;
2299                         return;
2300                 }
2301
2302                 /* now we have all points we need, collect their angles and sort them clockwise */
2303
2304                 for (i = 0; i < (*tot); i++) {
2305                         cent[0] += isectVCosSS[i][0];
2306                         cent[1] += isectVCosSS[i][1];
2307                 }
2308                 cent[0] = cent[0] / (float)(*tot);
2309                 cent[1] = cent[1] / (float)(*tot);
2310
2311
2312
2313                 /* Collect angles for every point around the center point */
2314
2315
2316 #if 0   /* uses a few more cycles then the above loop */
2317                 for (i = 0; i < (*tot); i++) {
2318                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
2319                 }
2320 #endif
2321
2322                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
2323                 v1_clipSS[1] = cent[1] + 1.0f;
2324
2325                 for (i = 0; i < (*tot); i++) {
2326                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2327                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2328                         isectVCosSS[i][2] = atan2f(v1_clipSS[0] * v2_clipSS[1] - v1_clipSS[1] * v2_clipSS[0],
2329                                                    v1_clipSS[0] * v2_clipSS[0] + v1_clipSS[1] * v2_clipSS[1]);
2330                 }
2331
2332                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
2333                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
2334
2335                 doubles = true;
2336                 while (doubles == true) {
2337                         doubles = false;
2338
2339                         for (i = 0; i < (*tot); i++) {
2340                                 if (fabsf(isectVCosSS[(i + 1) % *tot][0] - isectVCosSS[i][0]) < PROJ_PIXEL_TOLERANCE &&
2341                                     fabsf(isectVCosSS[(i + 1) % *tot][1] - isectVCosSS[i][1]) < PROJ_PIXEL_TOLERANCE)
2342                                 {
2343                                         int j;
2344                                         for (j = i; j < (*tot) - 1; j++) {
2345                                                 isectVCosSS[j][0] = isectVCosSS[j + 1][0];
2346                                                 isectVCosSS[j][1] = isectVCosSS[j + 1][1];
2347                                         }
2348                                         doubles = true; /* keep looking for more doubles */
2349                                         (*tot)--;
2350                                 }
2351                         }
2352                         
2353                         /* its possible there is only a few left after remove doubles */
2354                         if ((*tot) < 3) {
2355                                 // printf("removed too many doubles B\n");
2356                                 *tot = 0;
2357                                 return;
2358                         }
2359                 }
2360
2361                 if (is_ortho) {
2362                         for (i = 0; i < (*tot); i++) {
2363                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2364                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2365                         }
2366                 }
2367                 else {
2368                         for (i = 0; i < (*tot); i++) {
2369                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2370                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2371                         }
2372                 }
2373         }
2374
2375 #ifdef PROJ_DEBUG_PRINT_CLIP
2376         /* include this at the bottom of the above function to debug the output */
2377
2378         {
2379                 /* If there are ever any problems, */
2380                 float test_uv[4][2];
2381                 int i;
2382                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2383                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2384                 printf("(  [(%f,%f), (%f,%f), (%f,%f), (%f,%f)], ",
2385                        test_uv[0][0], test_uv[0][1],   test_uv[1][0], test_uv[1][1],
2386                        test_uv[2][0], test_uv[2][1],    test_uv[3][0], test_uv[3][1]);
2387
2388                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2389
2390                 printf("[");
2391                 for (i = 0; i < (*tot); i++) {
2392                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2393                 }
2394                 printf("]),\\\n");
2395         }
2396 #endif
2397 }
2398
2399 /*
2400  * # This script creates faces in a blender scene from printed data above.
2401  *
2402  * project_ls = [
2403  * ...(output from above block)...
2404  * ]
2405  *
2406  * from Blender import Scene, Mesh, Window, sys, Mathutils
2407  *
2408  * import bpy
2409  *
2410  * V = Mathutils.Vector
2411  *
2412  * def main():
2413  *     sce = bpy.data.scenes.active
2414  *
2415  *     for item in project_ls:
2416  *         bb = item[0]
2417  *         uv = item[1]
2418  *         poly = item[2]
2419  *
2420  *         me = bpy.data.meshes.new()
2421  *         ob = sce.objects.new(me)
2422  *
2423  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2424  *         me.faces.extend([(0,1,2,3),])
2425  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2426  *         me.faces.extend([(4,5,6),])
2427  *
2428  *         vs = [V(p).xyz for p in poly]
2429  *         print len(vs)
2430  *         l = len(me.verts)
2431  *         me.verts.extend(vs)
2432  *
2433  *         i = l
2434  *         while i < len(me.verts):
2435  *             ii = i + 1
2436  *             if ii == len(me.verts):
2437  *                 ii = l
2438  *             me.edges.extend([i, ii])
2439  *             i += 1
2440  *
2441  * if __name__ == '__main__':
2442  *     main()
2443  */
2444
2445
2446 #undef ISECT_1
2447 #undef ISECT_2
2448 #undef ISECT_3
2449 #undef ISECT_4
2450 #undef ISECT_ALL3
2451 #undef ISECT_ALL4
2452
2453
2454 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2455  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2456 static bool IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2457 {
2458         int i;
2459         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2460                 return 0;
2461
2462         for (i = 1; i < tot; i++) {
2463                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2464                         return 0;
2465
2466         }
2467
2468         return 1;
2469 }
2470 static bool IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2471 {
2472         int i;
2473         bool side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2474
2475         for (i = 1; i < tot; i++) {
2476                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2477                         return 0;
2478
2479         }
2480
2481         return 1;
2482 }
2483
2484 /* One of the most important function for projection painting,
2485  * since it selects the pixels to be added into each bucket.
2486  *
2487  * initialize pixels from this face where it intersects with the bucket_index,
2488  * optionally initialize pixels for removing seams */
2489 static void project_paint_face_init(
2490         const ProjPaintState *ps,
2491         const int thread_index, const int bucket_index, const int tri_index, const int image_index,
2492         const rctf *clip_rect, const rctf *bucket_bounds, ImBuf *ibuf, ImBuf **tmpibuf,
2493         const bool clamp_u, const bool clamp_v)
2494 {
2495         /* Projection vars, to get the 3D locations into screen space  */
2496         MemArena *arena = ps->arena_mt[thread_index];
2497         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2498         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2499         bool threaded = (ps->thread_tot > 1);
2500
2501         TileInfo tinf = {
2502                 ps->tile_lock,
2503                 ps->do_masking,
2504                 IMAPAINT_TILE_NUMBER(ibuf->x),
2505                 tmpibuf,
2506                 ps->projImages + image_index
2507         };
2508
2509         const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
2510         const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
2511         const float *lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv, lt) };
2512
2513         /* UV/pixel seeking data */
2514         int x; /* Image X-Pixel */
2515         int y; /* Image Y-Pixel */
2516         float mask;
2517         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2518
2519         const float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to lt_vtri[0-2] */
2520
2521         const float *vCo[3]; /* vertex screenspace coords */
2522
2523         float w[3], wco[3];
2524
2525         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to lt_tri_uv[0],1,2 or lt_tri_uv[0],2,3 */
2526         float pixelScreenCo[4];
2527         bool do_3d_mapping = ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D;
2528
2529         rcti bounds_px; /* ispace bounds */
2530         /* vars for getting uvspace bounds */
2531
2532         float lt_uv_pxoffset[3][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2533         float xhalfpx, yhalfpx;
2534         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2535
2536         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2537
2538         float uv_clip[8][2];
2539         int uv_clip_tot;
2540         const bool is_ortho = ps->is_ortho;
2541         const bool is_flip_object = ps->is_flip_object;
2542         const bool do_backfacecull = ps->do_backfacecull;
2543         const bool do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2544
2545         vCo[0] = ps->dm_mvert[lt_vtri[0]].co;
2546         vCo[1] = ps->dm_mvert[lt_vtri[1]].co;
2547         vCo[2] = ps->dm_mvert[lt_vtri[2]].co;
2548
2549
2550         /* Use lt_uv_pxoffset instead of lt_tri_uv so we can offset the UV half a pixel
2551          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2552          * problems when wrapping negative coords */
2553         xhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 3.0f))) / ibuf_xf;
2554         yhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 4.0f))) / ibuf_yf;
2555
2556         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2557          * Needed to add this offset since UV coords are often quads aligned to pixels.
2558          * In this case pixels can be exactly between 2 triangles causing nasty
2559          * artifacts.
2560          *
2561          * This workaround can be removed and painting will still work on most cases
2562          * but since the first thing most people try is painting onto a quad- better make it work.
2563          */
2564
2565         lt_uv_pxoffset[0][0] = lt_tri_uv[0][0] - xhalfpx;
2566         lt_uv_pxoffset[0][1] = lt_tri_uv[0][1] - yhalfpx;
2567
2568         lt_uv_pxoffset[1][0] = lt_tri_uv[1][0] - xhalfpx;
2569         lt_uv_pxoffset[1][1] = lt_tri_uv[1][1] - yhalfpx;
2570
2571         lt_uv_pxoffset[2][0] = lt_tri_uv[2][0] - xhalfpx;
2572         lt_uv_pxoffset[2][1] = lt_tri_uv[2][1] - yhalfpx;
2573
2574         {
2575                 uv1co = lt_uv_pxoffset[0]; // was lt_tri_uv[i1];
2576                 uv2co = lt_uv_pxoffset[1]; // was lt_tri_uv[i2];
2577                 uv3co = lt_uv_pxoffset[2]; // was lt_tri_uv[i3];
2578
2579                 v1coSS = ps->screenCoords[lt_vtri[0]];
2580                 v2coSS = ps->screenCoords[lt_vtri[1]];
2581                 v3coSS = ps->screenCoords[lt_vtri[2]];
2582
2583                 /* This funtion gives is a concave polyline in UV space from the clipped tri*/
2584                 project_bucket_clip_face(
2585                         is_ortho, is_flip_object,
2586                         clip_rect, bucket_bounds,
2587                         v1coSS, v2coSS, v3coSS,
2588                         uv1co, uv2co, uv3co,
2589                         uv_clip, &uv_clip_tot,
2590                         do_backfacecull || ps->do_occlude);
2591
2592                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2593 #if 0
2594                 if (uv_clip_tot > 6) {
2595                         printf("this should never happen! %d\n", uv_clip_tot);
2596                 }
2597 #endif
2598
2599                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2600
2601                         if (clamp_u) {
2602                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2603                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2604                         }
2605
2606                         if (clamp_v) {
2607                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2608                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2609                         }
2610
2611 #if 0
2612                         project_paint_undo_tiles_init(&bounds_px, ps->projImages + image_index, tmpibuf,
2613                                                       tile_width, threaded, ps->do_masking);
2614 #endif
2615                         /* clip face and */
2616
2617                         has_isect = 0;
2618                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2619                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2620                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2621
2622                                 has_x_isect = 0;
2623                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2624                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2625                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2626
2627                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2628                                          * could check the poly direction but better to do this */
2629                                         if ((do_backfacecull == true  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2630                                             (do_backfacecull == false && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2631                                         {
2632
2633                                                 has_x_isect = has_isect = 1;
2634
2635                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2636                                                 else screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2637
2638                                                 /* a pity we need to get the worldspace pixel location here */
2639                                                 if (do_clip || do_3d_mapping) {
2640                                                         interp_v3_v3v3v3(
2641                                                                 wco,
2642                                                                 ps->dm_mvert[lt_vtri[0]].co,
2643                                                                 ps->dm_mvert[lt_vtri[1]].co,
2644                                                                 ps->dm_mvert[lt_vtri[2]].co,
2645                                                                 w);
2646                                                         if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2647                                                                 continue; /* Watch out that no code below this needs to run */
2648                                                         }
2649                                                 }
2650
2651                                                 /* Is this UV visible from the view? - raytrace */
2652                                                 /* project_paint_PickFace is less complex, use for testing */
2653                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == tri_index) {
2654                                                 if ((ps->do_occlude == false) ||
2655                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, tri_index, pixelScreenCo))
2656                                                 {
2657                                                         mask = project_paint_uvpixel_mask(ps, tri_index, w);
2658
2659                                                         if (mask > 0.0f) {
2660                                                                 BLI_linklist_prepend_arena(
2661                                                                         bucketPixelNodes,
2662                                                                         project_paint_uvpixel_init(ps, arena, &tinf, x, y, mask, tri_index,
2663                                                                                                    pixelScreenCo, wco, w),
2664                                                                         arena
2665                                                                         );
2666                                                         }
2667                                                 }
2668
2669                                         }
2670 //#if 0
2671                                         else if (has_x_isect) {
2672                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2673                                                 break;
2674                                         }
2675 //#endif
2676                                 }
2677
2678
2679 #if 0           /* TODO - investigate why this dosnt work sometimes! it should! */
2680                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2681                                 if (has_x_isect == 0 && has_isect) {
2682                                         break;
2683                                 }
2684 #endif
2685                         }
2686                 }
2687         }
2688
2689
2690 #ifndef PROJ_DEBUG_NOSEAMBLEED
2691         if (ps->seam_bleed_px > 0.0f) {
2692                 int face_seam_flag;
2693
2694                 if (threaded)
2695                         BLI_lock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2696
2697                 face_seam_flag = ps->faceSeamFlags[tri_index];
2698
2699                 /* are any of our edges un-initialized? */
2700                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_NOSEAM1)) == 0 ||
2701                     (face_seam_flag & (PROJ_FACE_SEAM2 | PROJ_FACE_NOSEAM2)) == 0 ||
2702                     (face_seam_flag & (PROJ_FACE_SEAM3 | PROJ_FACE_NOSEAM3)) == 0)
2703                 {
2704                         project_face_seams_init(ps, tri_index);
2705                         face_seam_flag = ps->faceSeamFlags[tri_index];
2706                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3);
2707                 }
2708
2709                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_SEAM2 | PROJ_FACE_SEAM3)) == 0) {
2710
2711                         if (threaded)
2712                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2713
2714                 }
2715                 else {
2716                         /* we have a seam - deal with it! */
2717
2718                         /* Now create new UV's for the seam face */
2719                         float (*outset_uv)[2] = ps->faceSeamUVs[tri_index];
2720                         float insetCos[3][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2721
2722                         const float *vCoSS[3]; /* vertex screenspace coords */
2723
2724                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2725                         float edge_verts_inset_clip[2][3];
2726                         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 */
2727
2728                         float seam_subsection[4][2];
2729                         float fac1, fac2;
2730
2731                         if (outset_uv[0][0] == FLT_MAX) /* first time initialize */
2732                                 uv_image_outset(
2733                                         lt_uv_pxoffset, outset_uv, ps->seam_bleed_px,
2734                                         ibuf->x, ibuf->y, (ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_CW) == 0);
2735
2736                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2737                         if (threaded)
2738                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2739
2740                         vCoSS[0] = ps->screenCoords[lt_vtri[0]];
2741                         vCoSS[1] = ps->screenCoords[lt_vtri[1]];
2742                         vCoSS[2] = ps->screenCoords[lt_vtri[2]];
2743
2744                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2745                         if (is_ortho) {
2746                                 scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2747                         }
2748                         else {
2749                                 scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2750                         }
2751
2752                         for (fidx1 = 0; fidx1 < 3; fidx1++) {
2753                                 fidx2 = (fidx1 == 2) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2) -> (1,2,0) */
2754
2755                                 if ((face_seam_flag & (1 << fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2756                                     line_clip_rect2f(clip_rect, bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1]))
2757                                 {
2758                                         if (len_squared_v2v2(vCoSS[fidx1], vCoSS[fidx2]) > FLT_EPSILON) { /* avoid div by zero */
2759
2760                                                 if (is_ortho) {
2761                                                         fac1 = line_point_factor_v2(bucket_clip_edges[0], vCoSS[fidx1], vCoSS[fidx2]);
2762                                                         fac2 = line_point_factor_v2(bucket_clip_edges[1], vCoSS[fidx1], vCoSS[fidx2]);
2763                                                 }
2764                                                 else {
2765                                                         fac1 = screen_px_line_point_factor_v2_persp(ps, bucket_clip_edges[0], vCo[fidx1], vCo[fidx2]);
2766                                                         fac2 = screen_px_line_point_factor_v2_persp(ps, bucket_clip_edges[1], vCo[fidx1], vCo[fidx2]);
2767                                                 }
2768
2769                                                 interp_v2_v2v2(seam_subsection[0], lt_uv_pxoffset[fidx1], lt_uv_pxoffset[fidx2], fac1);
2770                                                 interp_v2_v2v2(seam_subsection[1], lt_uv_pxoffset[fidx1], lt_uv_pxoffset[fidx2], fac2);
2771
2772                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2773                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2774
2775                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2776                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2777                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2778                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2779
2780
2781                                                 if (pixel_bounds_uv((const float (*)[2])seam_subsection, &bounds_px, ibuf->x, ibuf->y)) {
2782                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2783
2784                                                         has_isect = 0;
2785                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2786                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2787                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2788
2789                                                                 has_x_isect = 0;
2790                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2791                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2792                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2793
2794                                                                         /* test we're inside uvspace bucket and triangle bounds */
2795                                                                         if (isect_point_quad_v2(uv, UNPACK4(seam_subsection))) {
2796                                                                                 float fac;
2797
2798                                                                                 /* We need to find the closest point along the face edge,
2799                                                                                  * getting the screen_px_from_*** wont work because our actual location
2800                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2801                                                                                  * our location on the side of the face's UV */
2802 #if 0
2803                                                                                 if (is_ortho) screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2804                                                                                 else          screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2805 #endif
2806
2807                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2808                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2809                                                                                 fac = resolve_quad_u_v2(uv, UNPACK4(seam_subsection));
2810                                                                                 interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac);
2811
2812                                                                                 if (!is_ortho) {
2813                                                                                         pixelScreenCo[3] = 1.0f;
2814                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2815                                                                                         pixelScreenCo[0] = (float)(ps->winx * 0.5f) + (ps->winx * 0.5f) * pixelScreenCo[0] / pixelScreenCo[3];
2816                                                                                         pixelScreenCo[1] = (float)(ps->winy * 0.5f) + (ps->winy * 0.5f) * pixelScreenCo[1] / pixelScreenCo[3];
2817                                                                                         pixelScreenCo[2] = pixelScreenCo[2] / pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2818                                                                                 }
2819
2820                                                                                 if ((ps->do_occlude == false) ||
2821                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, tri_index, pixelScreenCo))
2822                                                                                 {
2823                                                                                         /* Only bother calculating the weights if we intersect */
2824                                                                                         if (ps->do_mask_normal || ps->dm_mloopuv_clone) {
2825                                                                                                 const float uv_fac = fac1 + (fac * (fac2 - fac1));
2826 #if 0
2827                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2828                                                                                                 float uv_close[2];
2829                                                                                                 interp_v2_v2v2(uv_close, lt_uv_pxoffset[fidx1], lt_uv_pxoffset[fidx2], uv_fac);
2830                                                                                                 barycentric_weights_v2(lt_uv_pxoffset[0], lt_uv_pxoffset[1], lt_uv_pxoffset[2], uv_close, w);
2831 #else
2832
2833                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2834                                                                                                 w[0] = w[1] = w[2] = 0.0;
2835                                                                                                 w[fidx1] = 1.0f - uv_fac;
2836                                                                                                 w[fidx2] = uv_fac;
2837 #endif
2838                                                                                         }
2839
2840                                                                                         /* a pity we need to get the worldspace pixel location here */
2841                                                                                         if (do_clip || do_3d_mapping) {
2842                                                                                                 interp_v3_v3v3v3(wco, vCo[0], vCo[1], vCo[2], w);
2843
2844                                                                                                 if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2845                                                                                                         continue; /* Watch out that no code below this needs to run */
2846                                                                                                 }
2847                                                                                         }
2848
2849                                                                                         mask = project_paint_uvpixel_mask(ps, tri_index, w);
2850
2851                                                                                         if (mask > 0.0f) {
2852                                                                                                 BLI_linklist_prepend_arena(
2853                                                                                                         bucketPixelNodes,
2854                                                                                                         project_paint_uvpixel_init(ps, arena, &tinf, x, y, mask, tri_index,
2855                                                                                                         pixelScreenCo, wco, w),
2856                                                                                                         arena
2857                                                                                                         );
2858                                                                                         }
2859
2860                                                                                 }
2861                                                                         }
2862                                                                         else if (has_x_isect) {
2863                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2864                                                                                 break;
2865                                                                         }
2866                                                                 }
2867
2868 #if 0                           /* TODO - investigate why this dosnt work sometimes! it should! */
2869                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2870                                                                 if (has_x_isect == 0 && has_isect) {
2871                                                                         break;
2872                                                                 }
2873 #endif
2874                                                         }
2875                                                 }
2876                                         }
2877                                 }
2878                         }
2879                 }
2880         }
2881 #else
2882         UNUSED_VARS(vCo, threaded);
2883 #endif // PROJ_DEBUG_NOSEAMBLEED
2884 }
2885
2886
2887 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2888 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2889 {
2890         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2891         /* 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 */
2892         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 */
2893         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2894
2895         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2896         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2897
2898         /* in case the rect is outside the mesh 2d bounds */
2899         CLAMP(bucketMin[0], 0, ps->buckets_x);
2900         CLAMP(bucketMin[1], 0, ps->buckets_y);
2901
2902         CLAMP(bucketMax[0], 0, ps->buckets_x);
2903         CLAMP(bucketMax[1], 0, ps->buckets_y);
2904 }
2905
2906 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2907 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2908 {
2909         bucket_bounds->xmin = ps->screenMin[0] + ((bucket_x) * (ps->screen_width / ps->buckets_x));     /* left */
2910         bucket_bounds->xmax = ps->screenMin[0] + ((bucket_x + 1) * (ps->screen_width / ps->buckets_x)); /* right */
2911
2912         bucket_bounds->ymin = ps->screenMin[1] + ((bucket_y) * (ps->screen_height / ps->buckets_y));      /* bottom */
2913         bucket_bounds->ymax = ps->screenMin[1] + ((bucket_y + 1) * (ps->screen_height  / ps->buckets_y)); /* top */
2914 }
2915
2916 /* Fill this bucket with pixels from the faces that intersect it.
2917  *
2918  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2919 static void project_bucket_init(
2920         const ProjPaintState *ps, const int thread_index, const int bucket_index,
2921         const rctf *clip_rect, const rctf *bucket_bounds)
2922 {
2923         LinkNode *node;
2924         int tri_index, image_index = 0;
2925         ImBuf *ibuf = NULL;
2926         Image *tpage_last = NULL, *tpage;
2927         Image *ima = NULL;
2928         ImBuf *tmpibuf = NULL;
2929
2930         if (ps->image_tot == 1) {
2931                 /* Simple loop, no context switching */
2932                 ibuf = ps->projImages[0].ibuf;
2933                 ima = ps->projImages[0].ima;
2934
2935                 for (node = ps->bucketFaces[