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_meshdata_types.h"
62 #include "DNA_node_types.h"
63 #include "DNA_object_types.h"
64
65 #include "BKE_camera.h"
66 #include "BKE_colorband.h"
67 #include "BKE_context.h"
68 #include "BKE_colortools.h"
69 #include "BKE_idprop.h"
70 #include "BKE_brush.h"
71 #include "BKE_image.h"
72 #include "BKE_library.h"
73 #include "BKE_main.h"
74 #include "BKE_material.h"
75 #include "BKE_mesh.h"
76 #include "BKE_mesh_mapping.h"
77 #include "BKE_mesh_runtime.h"
78 #include "BKE_node.h"
79 #include "BKE_paint.h"
80 #include "BKE_report.h"
81 #include "BKE_scene.h"
82 #include "BKE_texture.h"
83
84 #include "DEG_depsgraph.h"
85 #include "DEG_depsgraph_query.h"
86
87 #include "UI_interface.h"
88
89 #include "ED_object.h"
90 #include "ED_mesh.h"
91 #include "ED_node.h"
92 #include "ED_paint.h"
93 #include "ED_screen.h"
94 #include "ED_uvedit.h"
95 #include "ED_view3d.h"
96
97 #include "GPU_extensions.h"
98
99 #include "WM_api.h"
100 #include "WM_types.h"
101
102 #include "RNA_access.h"
103 #include "RNA_define.h"
104 #include "RNA_enum_types.h"
105
106 #include "GPU_draw.h"
107
108 #include "IMB_colormanagement.h"
109
110 #include "bmesh.h"
111 //#include "bmesh_tools.h"
112
113 #include "paint_intern.h"
114
115 static void partial_redraw_array_init(ImagePaintPartialRedraw *pr);
116
117 /* Defines and Structs */
118 /* unit_float_to_uchar_clamp as inline function */
119 BLI_INLINE unsigned char f_to_char(const float val)
120 {
121         return unit_float_to_uchar_clamp(val);
122 }
123
124 /* ProjectionPaint defines */
125
126 /* approx the number of buckets to have under the brush,
127  * used with the brush size to set the ps->buckets_x and ps->buckets_y value.
128  *
129  * When 3 - a brush should have ~9 buckets under it at once
130  * ...this helps for threading while painting as well as
131  * avoiding initializing pixels that wont touch the brush */
132 #define PROJ_BUCKET_BRUSH_DIV 4
133
134 #define PROJ_BUCKET_RECT_MIN 4
135 #define PROJ_BUCKET_RECT_MAX 256
136
137 #define PROJ_BOUNDBOX_DIV 8
138 #define PROJ_BOUNDBOX_SQUARED  (PROJ_BOUNDBOX_DIV * PROJ_BOUNDBOX_DIV)
139
140 //#define PROJ_DEBUG_PAINT 1
141 //#define PROJ_DEBUG_NOSEAMBLEED 1
142 //#define PROJ_DEBUG_PRINT_CLIP 1
143 #define PROJ_DEBUG_WINCLIP 1
144
145
146 #ifndef PROJ_DEBUG_NOSEAMBLEED
147 /* projectFaceSeamFlags options */
148 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
149 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
150 #define PROJ_FACE_SEAM1 (1 << 0)  /* If this face has a seam on any of its edges */
151 #define PROJ_FACE_SEAM2 (1 << 1)
152 #define PROJ_FACE_SEAM3 (1 << 2)
153
154 #define PROJ_FACE_NOSEAM1   (1 << 4)
155 #define PROJ_FACE_NOSEAM2   (1 << 5)
156 #define PROJ_FACE_NOSEAM3   (1 << 6)
157
158 /* face winding */
159 #define PROJ_FACE_WINDING_INIT 1
160 #define PROJ_FACE_WINDING_CW 2
161
162 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
163  * as this number approaches  1.0f the likelihood increases of float precision errors where
164  * it is occluded by an adjacent face */
165 #define PROJ_FACE_SCALE_SEAM    0.99f
166 #endif  /* PROJ_DEBUG_NOSEAMBLEED */
167
168
169 #define PROJ_SRC_VIEW       1
170 #define PROJ_SRC_IMAGE_CAM  2
171 #define PROJ_SRC_IMAGE_VIEW 3
172 #define PROJ_SRC_VIEW_FILL  4
173
174 #define PROJ_VIEW_DATA_ID "view_data"
175 #define PROJ_VIEW_DATA_SIZE (4 * 4 + 4 * 4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
176
177 #define PROJ_BUCKET_NULL        0
178 #define PROJ_BUCKET_INIT        (1 << 0)
179 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
180
181 /* used for testing doubles, if a point is on a line etc */
182 #define PROJ_GEOM_TOLERANCE 0.00075f
183 #define PROJ_PIXEL_TOLERANCE 0.01f
184
185 /* vert flags */
186 #define PROJ_VERT_CULL 1
187
188 /* to avoid locking in tile initialization */
189 #define TILE_PENDING SET_INT_IN_POINTER(-1)
190
191 /* This is mainly a convenience struct used so we can keep an array of images we use -
192  * their imbufs, etc, in 1 array, When using threads this array is copied for each thread
193  * because 'partRedrawRect' and 'touch' values would not be thread safe */
194 typedef struct ProjPaintImage {
195         Image *ima;
196         ImBuf *ibuf;
197         ImagePaintPartialRedraw *partRedrawRect;
198         volatile void **undoRect; /* only used to build undo tiles during painting */
199         unsigned short **maskRect; /* the mask accumulation must happen on canvas, not on space screen bucket.
200                                     * Here we store the mask rectangle */
201         bool **valid; /* store flag to enforce validation of undo rectangle */
202         bool touch;
203 } ProjPaintImage;
204
205 /**
206  * Handle for stroke (operator customdata)
207  */
208 typedef struct ProjStrokeHandle {
209         /* Support for painting from multiple views at once,
210          * currently used to implement symmetry painting,
211          * we can assume at least the first is set while painting. */
212         struct ProjPaintState *ps_views[8];
213         int ps_views_tot;
214         int symmetry_flags;
215
216         int orig_brush_size;
217
218         bool need_redraw;
219
220         /* trick to bypass regular paint and allow clone picking */
221         bool is_clone_cursor_pick;
222
223         /* In ProjPaintState, only here for convenience */
224         Scene *scene;
225         Brush *brush;
226 } ProjStrokeHandle;
227
228 /* Main projection painting struct passed to all projection painting functions */
229 typedef struct ProjPaintState {
230         View3D *v3d;
231         RegionView3D *rv3d;
232         ARegion *ar;
233         Depsgraph *depsgraph;
234         Scene *scene;
235         int source; /* PROJ_SRC_**** */
236
237         /* the paint color. It can change depending of inverted mode or not */
238         float paint_color[3];
239         float paint_color_linear[3];
240         float dither;
241
242         Brush *brush;
243         short tool, blend, mode;
244
245         float brush_size;
246         Object *ob;
247         /* for symmetry, we need to store modified object matrix */
248         float obmat[4][4];
249         float obmat_imat[4][4];
250         /* end similarities with ImagePaintState */
251
252         Image *stencil_ima;
253         Image *canvas_ima;
254         Image *clone_ima;
255         float stencil_value;
256
257         /* projection painting only */
258         MemArena *arena_mt[BLENDER_MAX_THREADS]; /* for multithreading, the first item is sometimes used for non threaded cases too */
259         LinkNode **bucketRect;              /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
260         LinkNode **bucketFaces;             /* bucketRect aligned array linkList of faces overlapping each bucket */
261         unsigned char *bucketFlags;         /* store if the bucks have been initialized  */
262
263         char *vertFlags;                    /* store options per vert, now only store if the vert is pointing away from the view */
264         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 */
265         int buckets_y;
266
267         int pixel_sizeof;           /* result of project_paint_pixel_sizeof(), constant per stroke */
268
269         int image_tot;              /* size of projectImages array */
270
271         float (*screenCoords)[4];   /* verts projected into floating point screen space */
272         float screenMin[2];         /* 2D bounds for mesh verts on the screen's plane (screenspace) */
273         float screenMax[2];
274         float screen_width;         /* Calculated from screenMin & screenMax */
275         float screen_height;
276         int winx, winy;             /* from the carea or from the projection render */
277
278         /* options for projection painting */
279         bool  do_layer_clone;
280         bool  do_layer_stencil;
281         bool  do_layer_stencil_inv;
282         bool  do_stencil_brush;
283         bool  do_material_slots;
284
285         bool  do_occlude;               /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
286         bool  do_backfacecull;          /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
287         bool  do_mask_normal;           /* mask out pixels based on their normals */
288         bool  do_mask_cavity;           /* mask out pixels based on cavity */
289         float normal_angle;             /* what angle to mask at */
290         float normal_angle__cos;         /* cos(normal_angle), faster to compare */
291         float normal_angle_inner;
292         float normal_angle_inner__cos;
293         float normal_angle_range;       /* difference between normal_angle and normal_angle_inner, for easy access */
294
295         bool do_face_sel;               /* quick access to (me->editflag & ME_EDIT_PAINT_FACE_SEL) */
296         bool is_ortho;
297         bool is_flip_object;            /* the object is negative scaled */
298         bool do_masking;              /* use masking during painting. Some operations such as airbrush may disable */
299         bool is_texbrush;              /* only to avoid running  */
300         bool is_maskbrush;            /* mask brush is applied before masking */
301 #ifndef PROJ_DEBUG_NOSEAMBLEED
302         float seam_bleed_px;
303 #endif
304         /* clone vars */
305         float cloneOffset[2];
306
307         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
308         float projectMatInv[4][4];  /* inverse of projectMat */
309         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
310         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
311         float clipsta, clipend;
312
313         /* reproject vars */
314         Image *reproject_image;
315         ImBuf *reproject_ibuf;
316         bool   reproject_ibuf_free_float;
317         bool   reproject_ibuf_free_uchar;
318
319         /* threads */
320         int thread_tot;
321         int bucketMin[2];
322         int bucketMax[2];
323         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
324
325         struct CurveMapping *cavity_curve;
326         BlurKernel *blurkernel;
327
328
329
330         /* -------------------------------------------------------------------- */
331         /* Vars shared between multiple views (keep last) */
332         /**
333          * This data is owned by ``ProjStrokeHandle.ps_views[0]``,
334          * all other views re-use the data.
335          */
336
337 #define PROJ_PAINT_STATE_SHARED_MEMCPY(ps_dst, ps_src) \
338         MEMCPY_STRUCT_OFS(ps_dst, ps_src, is_shared_user)
339
340 #define PROJ_PAINT_STATE_SHARED_CLEAR(ps) \
341         MEMSET_STRUCT_OFS(ps, 0, is_shared_user)
342
343         bool is_shared_user;
344
345         ProjPaintImage *projImages;
346         float *cavities;            /* cavity amount for vertices */
347
348 #ifndef PROJ_DEBUG_NOSEAMBLEED
349         char *faceSeamFlags;                /* store info about faces, if they are initialized etc*/
350         char *faceWindingFlags;             /* save the winding of the face in uv space, helps as an extra validation step for seam detection */
351         float (*faceSeamUVs)[3][2];         /* expanded UVs for faces to use as seams */
352         LinkNode **vertFaces;               /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
353 #endif
354
355         SpinLock *tile_lock;
356
357         Mesh *me_eval;
358         int  totlooptri_eval;
359         int  totpoly_eval;
360         int  totedge_eval;
361         int  totvert_eval;
362
363         const MVert    *mvert_eval;
364         const MEdge    *medge_eval;
365         const MPoly    *mpoly_eval;
366         const MLoop    *mloop_eval;
367         const MLoopTri *mlooptri_eval;
368
369         const MLoopUV  *mloopuv_stencil_eval;
370
371         /**
372          * \note These UV layers are aligned to \a mpoly_eval
373          * but each pointer references the start of the layer,
374          * so a loop indirection is needed as well.
375          */
376         const MLoopUV **poly_to_loop_uv;
377         const MLoopUV **poly_to_loop_uv_clone;    /* other UV map, use for cloning between layers */
378
379         /* Actual material for each index, either from object or Mesh datablock... */
380         Material **mat_array;
381
382         bool use_colormanagement;
383 } ProjPaintState;
384
385 typedef union pixelPointer {
386         float *f_pt;            /* float buffer */
387         unsigned int *uint_pt; /* 2 ways to access a char buffer */
388         unsigned char *ch_pt;
389 } PixelPointer;
390
391 typedef union pixelStore {
392         unsigned char ch[4];
393         unsigned int uint;
394         float f[4];
395 } PixelStore;
396
397 typedef struct ProjPixel {
398         float projCoSS[2]; /* the floating point screen projection of this pixel */
399         float worldCoSS[3];
400
401         short x_px, y_px;
402
403         unsigned short image_index; /* if anyone wants to paint onto more than 65535 images they can bite me */
404         unsigned char bb_cell_index;
405
406         /* for various reasons we may want to mask out painting onto this pixel */
407         unsigned short mask;
408
409         /* Only used when the airbrush is disabled.
410          * Store the max mask value to avoid painting over an area with a lower opacity
411          * with an advantage that we can avoid touching the pixel at all, if the
412          * new mask value is lower then mask_accum */
413         unsigned short *mask_accum;
414
415         /* horrible hack, store tile valid flag pointer here to re-validate tiles used for anchored and drag-dot strokes */
416         bool *valid;
417
418         PixelPointer origColor;
419         PixelStore newColor;
420         PixelPointer pixel;
421 } ProjPixel;
422
423 typedef struct ProjPixelClone {
424         struct ProjPixel __pp;
425         PixelStore clonepx;
426 } ProjPixelClone;
427
428 /* undo tile pushing */
429 typedef struct {
430         SpinLock *lock;
431         bool masked;
432         unsigned short tile_width;
433         ImBuf **tmpibuf;
434         ProjPaintImage *pjima;
435 } TileInfo;
436
437
438
439 /* -------------------------------------------------------------------- */
440
441 /** \name MLoopTri accessor functions.
442  * \{ */
443
444 BLI_INLINE const MPoly *ps_tri_index_to_mpoly(const ProjPaintState *ps, int tri_index)
445 {
446         return &ps->mpoly_eval[ps->mlooptri_eval[tri_index].poly];
447 }
448
449 #define PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) \
450         ps->mloop_eval[lt->tri[0]].v, \
451         ps->mloop_eval[lt->tri[1]].v, \
452         ps->mloop_eval[lt->tri[2]].v,
453
454 #define PS_LOOPTRI_AS_UV_3(uvlayer, lt) \
455         uvlayer[lt->poly][lt->tri[0]].uv, \
456         uvlayer[lt->poly][lt->tri[1]].uv, \
457         uvlayer[lt->poly][lt->tri[2]].uv,
458
459 #define PS_LOOPTRI_ASSIGN_UV_3(uv_tri, uvlayer, lt)  { \
460         (uv_tri)[0] = uvlayer[lt->poly][lt->tri[0]].uv; \
461         (uv_tri)[1] = uvlayer[lt->poly][lt->tri[1]].uv; \
462         (uv_tri)[2] = uvlayer[lt->poly][lt->tri[2]].uv; \
463 } ((void)0)
464
465 /** \} */
466
467
468
469 /* Finish projection painting structs */
470
471 static TexPaintSlot *project_paint_face_paint_slot(const ProjPaintState *ps, int tri_index)
472 {
473         const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
474         Material *ma = ps->mat_array[mp->mat_nr];
475         return ma ? ma->texpaintslot + ma->paint_active_slot : NULL;
476 }
477
478 static Image *project_paint_face_paint_image(const ProjPaintState *ps, int tri_index)
479 {
480         if (ps->do_stencil_brush) {
481                 return ps->stencil_ima;
482         }
483         else {
484                 const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
485                 Material *ma = ps->mat_array[mp->mat_nr];
486                 TexPaintSlot *slot = ma ? ma->texpaintslot + ma->paint_active_slot : NULL;
487                 return slot ? slot->ima : ps->canvas_ima;
488         }
489 }
490
491 static TexPaintSlot *project_paint_face_clone_slot(const ProjPaintState *ps, int tri_index)
492 {
493         const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
494         Material *ma = ps->mat_array[mp->mat_nr];
495         return ma ? ma->texpaintslot + ma->paint_clone_slot : NULL;
496 }
497
498 static Image *project_paint_face_clone_image(const ProjPaintState *ps, int tri_index)
499 {
500         const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
501         Material *ma = ps->mat_array[mp->mat_nr];
502         TexPaintSlot *slot = ma ? ma->texpaintslot + ma->paint_clone_slot : NULL;
503         return slot ? slot->ima : ps->clone_ima;
504 }
505
506 /* fast projection bucket array lookup, use the safe version for bound checking  */
507 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
508 {
509         /* If we were not dealing with screenspace 2D coords we could simple do...
510          * ps->bucketRect[x + (y*ps->buckets_y)] */
511
512         /* please explain?
513          * projCoSS[0] - ps->screenMin[0]   : zero origin
514          * ... / ps->screen_width           : range from 0.0 to 1.0
515          * ... * ps->buckets_x              : use as a bucket index
516          *
517          * Second multiplication does similar but for vertical offset
518          */
519         return ( (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
520                (((int)(((projCoSS[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
521 }
522
523 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
524 {
525         int bucket_index = project_bucket_offset(ps, projCoSS);
526
527         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
528                 return -1;
529         }
530         else {
531                 return bucket_index;
532         }
533 }
534
535 static float VecZDepthOrtho(
536         const float pt[2],
537         const float v1[3], const float v2[3], const float v3[3],
538         float w[3])
539 {
540         barycentric_weights_v2(v1, v2, v3, pt, w);
541         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
542 }
543
544 static float VecZDepthPersp(
545         const float pt[2],
546         const float v1[4], const float v2[4], const float v3[4],
547         float w[3])
548 {
549         float wtot_inv, wtot;
550         float w_tmp[3];
551
552         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
553         /* for the depth we need the weights to match what
554          * barycentric_weights_v2 would return, in this case its easiest just to
555          * undo the 4th axis division and make it unit-sum
556          *
557          * don't call barycentric_weights_v2() because our callers expect 'w'
558          * to be weighted from the perspective */
559         w_tmp[0] = w[0] * v1[3];
560         w_tmp[1] = w[1] * v2[3];
561         w_tmp[2] = w[2] * v3[3];
562
563         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
564
565         if (wtot != 0.0f) {
566                 wtot_inv = 1.0f / wtot;
567
568                 w_tmp[0] = w_tmp[0] * wtot_inv;
569                 w_tmp[1] = w_tmp[1] * wtot_inv;
570                 w_tmp[2] = w_tmp[2] * wtot_inv;
571         }
572         else /* dummy values for zero area face */
573                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
574         /* done mimicing barycentric_weights_v2() */
575
576         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
577 }
578
579
580 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
581 static int project_paint_PickFace(
582         const ProjPaintState *ps, const float pt[2],
583         float w[3])
584 {
585         LinkNode *node;
586         float w_tmp[3];
587         int bucket_index;
588         int best_tri_index = -1;
589         float z_depth_best = FLT_MAX, z_depth;
590
591         bucket_index = project_bucket_offset_safe(ps, pt);
592         if (bucket_index == -1)
593                 return -1;
594
595
596
597         /* we could return 0 for 1 face buckets, as long as this function assumes
598          * that the point its testing is only every originated from an existing face */
599
600         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
601                 const int tri_index = GET_INT_FROM_POINTER(node->link);
602                 const MLoopTri *lt = &ps->mlooptri_eval[tri_index];
603                 const float *vtri_ss[3] = {
604                     ps->screenCoords[ps->mloop_eval[lt->tri[0]].v],
605                     ps->screenCoords[ps->mloop_eval[lt->tri[1]].v],
606                     ps->screenCoords[ps->mloop_eval[lt->tri[2]].v],
607                 };
608
609
610                 if (isect_point_tri_v2(pt, UNPACK3(vtri_ss))) {
611                         if (ps->is_ortho) {
612                                 z_depth = VecZDepthOrtho(pt, UNPACK3(vtri_ss), w_tmp);
613                         }
614                         else {
615                                 z_depth = VecZDepthPersp(pt, UNPACK3(vtri_ss), w_tmp);
616                         }
617
618                         if (z_depth < z_depth_best) {
619                                 best_tri_index = tri_index;
620                                 z_depth_best = z_depth;
621                                 copy_v3_v3(w, w_tmp);
622                         }
623                 }
624         }
625
626         return best_tri_index; /* will be -1 or a valid face */
627 }
628
629 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
630 static void uvco_to_wrapped_pxco(const float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
631 {
632         /* use */
633         *x = fmodf(uv[0], 1.0f);
634         *y = fmodf(uv[1], 1.0f);
635
636         if (*x < 0.0f) *x += 1.0f;
637         if (*y < 0.0f) *y += 1.0f;
638
639         *x = *x * ibuf_x - 0.5f;
640         *y = *y * ibuf_y - 0.5f;
641 }
642
643 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
644 static bool project_paint_PickColor(
645         const ProjPaintState *ps, const float pt[2],
646         float *rgba_fp, unsigned char *rgba, const bool interp)
647 {
648         const MLoopTri *lt;
649         const float *lt_tri_uv[3];
650         float w[3], uv[2];
651         int tri_index;
652         Image *ima;
653         ImBuf *ibuf;
654         int xi, yi;
655
656         tri_index = project_paint_PickFace(ps, pt, w);
657
658         if (tri_index == -1)
659                 return 0;
660
661         lt = &ps->mlooptri_eval[tri_index];
662         PS_LOOPTRI_ASSIGN_UV_3(lt_tri_uv, ps->poly_to_loop_uv, lt);
663
664         interp_v2_v2v2v2(uv, UNPACK3(lt_tri_uv), w);
665
666         ima = project_paint_face_paint_image(ps, tri_index);
667         ibuf = BKE_image_get_first_ibuf(ima); /* we must have got the imbuf before getting here */
668         if (!ibuf) return 0;
669
670         if (interp) {
671                 float x, y;
672                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
673
674                 if (ibuf->rect_float) {
675                         if (rgba_fp) {
676                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
677                         }
678                         else {
679                                 float rgba_tmp_f[4];
680                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
681                                 premul_float_to_straight_uchar(rgba, rgba_tmp_f);
682                         }
683                 }
684                 else {
685                         if (rgba) {
686                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
687                         }
688                         else {
689                                 unsigned char rgba_tmp[4];
690                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
691                                 straight_uchar_to_premul_float(rgba_fp, rgba_tmp);
692                         }
693                 }
694         }
695         else {
696                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
697                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
698                 //if (xi < 0 || xi >= ibuf->x  ||  yi < 0 || yi >= ibuf->y) return 0;
699
700                 /* wrap */
701                 xi = mod_i((int)(uv[0] * ibuf->x), ibuf->x);
702                 yi = mod_i((int)(uv[1] * ibuf->y), ibuf->y);
703
704                 if (rgba) {
705                         if (ibuf->rect_float) {
706                                 const float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
707                                 premul_float_to_straight_uchar(rgba, rgba_tmp_fp);
708                         }
709                         else {
710                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
711                         }
712                 }
713
714                 if (rgba_fp) {
715                         if (ibuf->rect_float) {
716                                 copy_v4_v4(rgba_fp, (ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
717                         }
718                         else {
719                                 unsigned char *tmp_ch = ((unsigned char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
720                                 straight_uchar_to_premul_float(rgba_fp, tmp_ch);
721                         }
722                 }
723         }
724         BKE_image_release_ibuf(ima, ibuf, NULL);
725         return 1;
726 }
727
728 /**
729  * Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusion test)
730  * \return
731  * -  `0`:   no occlusion
732  * - `-1`: no occlusion but 2D intersection is true
733  * -  `1`: occluded
734  * -  `2`: occluded with `w[3]` weights set (need to know in some cases)
735  */
736 static int project_paint_occlude_ptv(
737         const float pt[3],
738         const float v1[4], const float v2[4], const float v3[4],
739         float w[3], const bool is_ortho)
740 {
741         /* if all are behind us, return false */
742         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
743                 return 0;
744
745         /* do a 2D point in try intersection */
746         if (!isect_point_tri_v2(pt, v1, v2, v3))
747                 return 0;  /* we know there is  */
748
749
750         /* From here on we know there IS an intersection */
751         /* if ALL of the verts are infront of us then we know it intersects ? */
752         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
753                 return 1;
754         }
755         else {
756                 /* we intersect? - find the exact depth at the point of intersection */
757                 /* Is this point is occluded by another face? */
758                 if (is_ortho) {
759                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
760                 }
761                 else {
762                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
763                 }
764         }
765         return -1;
766 }
767
768
769 static int project_paint_occlude_ptv_clip(
770         const float pt[3],
771         const float v1[4], const float v2[4], const float v3[4],
772         const float v1_3d[3], const float v2_3d[3], const float v3_3d[3],
773         float w[3], const bool is_ortho, RegionView3D *rv3d)
774 {
775         float wco[3];
776         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, is_ortho);
777
778         if (ret <= 0)
779                 return ret;
780
781         if (ret == 1) { /* weights not calculated */
782                 if (is_ortho) {
783                         barycentric_weights_v2(v1, v2, v3, pt, w);
784                 }
785                 else {
786                         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
787                 }
788         }
789
790         /* Test if we're in the clipped area, */
791         interp_v3_v3v3v3(wco, v1_3d, v2_3d, v3_3d, w);
792
793         if (!ED_view3d_clipping_test(rv3d, wco, true)) {
794                 return 1;
795         }
796
797         return -1;
798 }
799
800
801 /* Check if a screenspace location is occluded by any other faces
802  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
803  * and doesn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
804 static bool project_bucket_point_occluded(
805         const ProjPaintState *ps, LinkNode *bucketFace,
806         const int orig_face, const float pixelScreenCo[4])
807 {
808         int isect_ret;
809         const bool do_clip = ps->rv3d ? (ps->rv3d->rflag & RV3D_CLIPPING) != 0 : 0;
810
811         /* we could return 0 for 1 face buckets, as long as this function assumes
812          * that the point its testing is only every originated from an existing face */
813
814         for (; bucketFace; bucketFace = bucketFace->next) {
815                 const int tri_index = GET_INT_FROM_POINTER(bucketFace->link);
816
817                 if (orig_face != tri_index) {
818                         const MLoopTri *lt = &ps->mlooptri_eval[tri_index];
819                         const float *vtri_ss[3] = {
820                             ps->screenCoords[ps->mloop_eval[lt->tri[0]].v],
821                             ps->screenCoords[ps->mloop_eval[lt->tri[1]].v],
822                             ps->screenCoords[ps->mloop_eval[lt->tri[2]].v],
823                         };
824                         float w[3];
825
826                         if (do_clip) {
827                                 const float *vtri_co[3] = {
828                                     ps->mvert_eval[ps->mloop_eval[lt->tri[0]].v].co,
829                                     ps->mvert_eval[ps->mloop_eval[lt->tri[1]].v].co,
830                                     ps->mvert_eval[ps->mloop_eval[lt->tri[2]].v].co,
831                                 };
832                                 isect_ret = project_paint_occlude_ptv_clip(
833                                         pixelScreenCo, UNPACK3(vtri_ss), UNPACK3(vtri_co),
834                                         w, ps->is_ortho, ps->rv3d);
835                         }
836                         else {
837                                 isect_ret = project_paint_occlude_ptv(
838                                         pixelScreenCo, UNPACK3(vtri_ss),
839                                         w, ps->is_ortho);
840                         }
841
842                         if (isect_ret >= 1) {
843                                 /* TODO - we may want to cache the first hit,
844                                  * it is not possible to swap the face order in the list anymore */
845                                 return true;
846                         }
847                 }
848         }
849         return false;
850 }
851
852 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
853  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
854 #define ISECT_TRUE 1
855 #define ISECT_TRUE_P1 2
856 #define ISECT_TRUE_P2 3
857 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
858 {
859         float y_diff;
860
861         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
862                 *x_isect = p1[0];
863                 return ISECT_TRUE_P1;
864         }
865         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
866                 *x_isect = p2[0];
867                 return ISECT_TRUE_P2;
868         }
869
870         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
871
872         if (y_diff < 0.000001f) {
873                 *x_isect = (p1[0] + p2[0]) * 0.5f;
874                 return ISECT_TRUE;
875         }
876
877         if (p1[1] > y_level && p2[1] < y_level) {
878                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /* (p1[1] - p2[1]); */
879                 return ISECT_TRUE;
880         }
881         else if (p1[1] < y_level && p2[1] > y_level) {
882                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /* (p2[1] - p1[1]); */
883                 return ISECT_TRUE;
884         }
885         else {
886                 return 0;
887         }
888 }
889
890 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
891 {
892         float x_diff;
893
894         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
895                 *y_isect = p1[1];
896                 return ISECT_TRUE_P1;
897         }
898         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
899                 *y_isect = p2[1];
900                 return ISECT_TRUE_P2;
901         }
902
903         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
904
905         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
906                 *y_isect = (p1[0] + p2[0]) * 0.5f;
907                 return ISECT_TRUE;
908         }
909
910         if (p1[0] > x_level && p2[0] < x_level) {
911                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff;  /* (p1[0] - p2[0]); */
912                 return ISECT_TRUE;
913         }
914         else if (p1[0] < x_level && p2[0] > x_level) {
915                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff;  /* (p2[0] - p1[0]); */
916                 return ISECT_TRUE;
917         }
918         else {
919                 return 0;
920         }
921 }
922
923 /* simple func use for comparing UV locations to check if there are seams.
924  * Its possible this gives incorrect results, when the UVs for 1 face go into the next
925  * tile, but do not do this for the adjacent face, it could return a false positive.
926  * This is so unlikely that Id not worry about it. */
927 #ifndef PROJ_DEBUG_NOSEAMBLEED
928 static bool cmp_uv(const float vec2a[2], const float vec2b[2])
929 {
930         /* if the UV's are not between 0.0 and 1.0 */
931         float xa = fmodf(vec2a[0], 1.0f);
932         float ya = fmodf(vec2a[1], 1.0f);
933
934         float xb = fmodf(vec2b[0], 1.0f);
935         float yb = fmodf(vec2b[1], 1.0f);
936
937         if (xa < 0.0f) xa += 1.0f;
938         if (ya < 0.0f) ya += 1.0f;
939
940         if (xb < 0.0f) xb += 1.0f;
941         if (yb < 0.0f) yb += 1.0f;
942
943         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
944 }
945 #endif
946
947 /* set min_px and max_px to the image space bounds of the UV coords
948  * return zero if there is no area in the returned rectangle */
949 #ifndef PROJ_DEBUG_NOSEAMBLEED
950 static bool pixel_bounds_uv(
951         const float uv_quad[4][2],
952         rcti *bounds_px,
953         const int ibuf_x, const int ibuf_y
954         )
955 {
956         float min_uv[2], max_uv[2]; /* UV bounds */
957
958         INIT_MINMAX2(min_uv, max_uv);
959
960         minmax_v2v2_v2(min_uv, max_uv, uv_quad[0]);
961         minmax_v2v2_v2(min_uv, max_uv, uv_quad[1]);
962         minmax_v2v2_v2(min_uv, max_uv, uv_quad[2]);
963         minmax_v2v2_v2(min_uv, max_uv, uv_quad[3]);
964
965         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
966         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
967
968         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
969         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
970
971         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
972
973         /* face uses no UV area when quantized to pixels? */
974         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
975 }
976 #endif
977
978 static bool pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
979 {
980         float min_uv[2], max_uv[2]; /* UV bounds */
981
982         if (tot == 0) {
983                 return 0;
984         }
985
986         INIT_MINMAX2(min_uv, max_uv);
987
988         while (tot--) {
989                 minmax_v2v2_v2(min_uv, max_uv, (*uv));
990                 uv++;
991         }
992
993         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
994         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
995
996         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
997         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
998
999         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
1000
1001         /* face uses no UV area when quantized to pixels? */
1002         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
1003 }
1004
1005 #ifndef PROJ_DEBUG_NOSEAMBLEED
1006
1007 static void project_face_winding_init(const ProjPaintState *ps, const int tri_index)
1008 {
1009         /* detect the winding of faces in uv space */
1010         const MLoopTri *lt = &ps->mlooptri_eval[tri_index];
1011         const float *lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->poly_to_loop_uv, lt) };
1012         float winding = cross_tri_v2(lt_tri_uv[0], lt_tri_uv[1], lt_tri_uv[2]);
1013
1014         if (winding > 0)
1015                 ps->faceWindingFlags[tri_index] |= PROJ_FACE_WINDING_CW;
1016
1017         ps->faceWindingFlags[tri_index] |= PROJ_FACE_WINDING_INIT;
1018 }
1019
1020 /* This function returns 1 if this face has a seam along the 2 face-vert indices
1021  * 'orig_i1_fidx' and 'orig_i2_fidx' */
1022 static bool check_seam(
1023         const ProjPaintState *ps,
1024         const int orig_face, const int orig_i1_fidx, const int orig_i2_fidx,
1025         int *other_face, int *orig_fidx)
1026 {
1027         const MLoopTri *orig_lt = &ps->mlooptri_eval[orig_face];
1028         const float *orig_lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->poly_to_loop_uv, orig_lt) };
1029         /* vert indices from face vert order indices */
1030         const unsigned int i1 = ps->mloop_eval[orig_lt->tri[orig_i1_fidx]].v;
1031         const unsigned int i2 = ps->mloop_eval[orig_lt->tri[orig_i2_fidx]].v;
1032         LinkNode *node;
1033         int i1_fidx = -1, i2_fidx = -1; /* index in face */
1034
1035         for (node = ps->vertFaces[i1]; node; node = node->next) {
1036                 const int tri_index = GET_INT_FROM_POINTER(node->link);
1037
1038                 if (tri_index != orig_face) {
1039                         const MLoopTri *lt = &ps->mlooptri_eval[tri_index];
1040                         const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
1041                         /* could check if the 2 faces images match here,
1042                          * but then there wouldn't be a way to return the opposite face's info */
1043
1044
1045                         /* We need to know the order of the verts in the adjacent face
1046                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
1047                         i1_fidx = BKE_MESH_TESSTRI_VINDEX_ORDER(lt_vtri, i1);
1048                         i2_fidx = BKE_MESH_TESSTRI_VINDEX_ORDER(lt_vtri, i2);
1049
1050                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
1051                         if (i2_fidx != -1) {
1052                                 const float *lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->poly_to_loop_uv, lt) };
1053                                 Image *tpage = project_paint_face_paint_image(ps, tri_index);
1054                                 Image *orig_tpage = project_paint_face_paint_image(ps, orig_face);
1055
1056                                 BLI_assert(i1_fidx != -1);
1057
1058                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
1059
1060                                 /* set up the other face */
1061                                 *other_face = tri_index;
1062
1063                                 /* we check if difference is 1 here, else we might have a case of edge 2-0 for a tri */
1064                                 *orig_fidx = (i1_fidx < i2_fidx && (i2_fidx - i1_fidx == 1)) ? i1_fidx : i2_fidx;
1065
1066                                 /* initialize face winding if needed */
1067                                 if ((ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_INIT) == 0)
1068                                         project_face_winding_init(ps, tri_index);
1069
1070                                 /* first test if they have the same image */
1071                                 if ((orig_tpage == tpage) &&
1072                                     cmp_uv(orig_lt_tri_uv[orig_i1_fidx], lt_tri_uv[i1_fidx]) &&
1073                                     cmp_uv(orig_lt_tri_uv[orig_i2_fidx], lt_tri_uv[i2_fidx]))
1074                                 {
1075                                         /* if faces don't have the same winding in uv space,
1076                                          * they are on the same side so edge is boundary */
1077                                         if ((ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_CW) !=
1078                                             (ps->faceWindingFlags[orig_face] & PROJ_FACE_WINDING_CW))
1079                                         {
1080                                                 return 1;
1081                                         }
1082
1083                                         // printf("SEAM (NONE)\n");
1084                                         return 0;
1085
1086                                 }
1087                                 else {
1088                                         // printf("SEAM (UV GAP)\n");
1089                                         return 1;
1090                                 }
1091                         }
1092                 }
1093         }
1094         // printf("SEAM (NO FACE)\n");
1095         *other_face = -1;
1096         return 1;
1097 }
1098
1099 #define SMALL_NUMBER  1.e-6f
1100 BLI_INLINE float shell_v2v2_normal_dir_to_dist(float n[2], float d[2])
1101 {
1102         const float angle_cos = (normalize_v2(n) < SMALL_NUMBER) ? fabsf(dot_v2v2(d, n)) : 0.0f;
1103         return (UNLIKELY(angle_cos < SMALL_NUMBER)) ? 1.0f : (1.0f / angle_cos);
1104 }
1105 #undef SMALL_NUMBER
1106
1107 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
1108  * since the outset coords are a margin that keep an even distance from the original UV's,
1109  * note that the image aspect is taken into account */
1110 static void uv_image_outset(
1111         float (*orig_uv)[2], float (*outset_uv)[2], const float scaler,
1112         const int ibuf_x, const int ibuf_y, const bool cw)
1113 {
1114         /* disallow shell-thickness to outset extreme values,
1115          * otherwise near zero area UV's may extend thousands of pixels. */
1116         const float scale_clamp = 5.0f;
1117
1118         float a1, a2, a3;
1119         float puv[3][2]; /* pixelspace uv's */
1120         float no1[2], no2[2], no3[2]; /* normals */
1121         float dir1[2], dir2[2], dir3[2];
1122         float ibuf_inv[2];
1123
1124         ibuf_inv[0] = 1.0f / (float)ibuf_x;
1125         ibuf_inv[1] = 1.0f / (float)ibuf_y;
1126
1127         /* make UV's in pixel space so we can */
1128         puv[0][0] = orig_uv[0][0] * ibuf_x;
1129         puv[0][1] = orig_uv[0][1] * ibuf_y;
1130
1131         puv[1][0] = orig_uv[1][0] * ibuf_x;
1132         puv[1][1] = orig_uv[1][1] * ibuf_y;
1133
1134         puv[2][0] = orig_uv[2][0] * ibuf_x;
1135         puv[2][1] = orig_uv[2][1] * ibuf_y;
1136
1137         /* face edge directions */
1138         sub_v2_v2v2(dir1, puv[1], puv[0]);
1139         sub_v2_v2v2(dir2, puv[2], puv[1]);
1140         sub_v2_v2v2(dir3, puv[0], puv[2]);
1141         normalize_v2(dir1);
1142         normalize_v2(dir2);
1143         normalize_v2(dir3);
1144
1145         /* here we just use the orthonormality property (a1, a2) dot (a2, -a1) = 0
1146          * to get normals from the edge directions based on the winding */
1147         if (cw) {
1148                 no1[0] = -dir3[1] - dir1[1];
1149                 no1[1] =  dir3[0] + dir1[0];
1150                 no2[0] = -dir1[1] - dir2[1];
1151                 no2[1] =  dir1[0] + dir2[0];
1152                 no3[0] = -dir2[1] - dir3[1];
1153                 no3[1] =  dir2[0] + dir3[0];
1154         }
1155         else {
1156                 no1[0] =  dir3[1] + dir1[1];
1157                 no1[1] = -dir3[0] - dir1[0];
1158                 no2[0] =  dir1[1] + dir2[1];
1159                 no2[1] = -dir1[0] - dir2[0];
1160                 no3[0] =  dir2[1] + dir3[1];
1161                 no3[1] = -dir2[0] - dir3[0];
1162         }
1163
1164         a1 = shell_v2v2_normal_dir_to_dist(no1, dir3);
1165         a2 = shell_v2v2_normal_dir_to_dist(no2, dir1);
1166         a3 = shell_v2v2_normal_dir_to_dist(no3, dir2);
1167
1168         CLAMP_MAX(a1, scale_clamp);
1169         CLAMP_MAX(a2, scale_clamp);
1170         CLAMP_MAX(a3, scale_clamp);
1171
1172         mul_v2_fl(no1, a1 * scaler);
1173         mul_v2_fl(no2, a2 * scaler);
1174         mul_v2_fl(no3, a3 * scaler);
1175         add_v2_v2v2(outset_uv[0], puv[0], no1);
1176         add_v2_v2v2(outset_uv[1], puv[1], no2);
1177         add_v2_v2v2(outset_uv[2], puv[2], no3);
1178
1179         mul_v2_v2(outset_uv[0], ibuf_inv);
1180         mul_v2_v2(outset_uv[1], ibuf_inv);
1181         mul_v2_v2(outset_uv[2], ibuf_inv);
1182 }
1183
1184 /*
1185  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1186  * 1<<i - where i is (0-3)
1187  *
1188  * If we're multithreadng, make sure threads are locked when this is called
1189  */
1190 static void project_face_seams_init(const ProjPaintState *ps, const int tri_index)
1191 {
1192         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1193         int fidx1 = 2;
1194         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 */
1195
1196         /* initialize face winding if needed */
1197         if ((ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_INIT) == 0)
1198                 project_face_winding_init(ps, tri_index);
1199
1200         do {
1201                 if ((ps->faceSeamFlags[tri_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1202                         if (check_seam(ps, tri_index, fidx1, fidx2, &other_face, &other_fidx)) {
1203                                 ps->faceSeamFlags[tri_index] |= 1 << fidx1;
1204                                 if (other_face != -1)
1205                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1206                         }
1207                         else {
1208                                 ps->faceSeamFlags[tri_index] |= 16 << fidx1;
1209                                 if (other_face != -1)
1210                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1211                         }
1212                 }
1213
1214                 fidx2 = fidx1;
1215         } while (fidx1--);
1216 }
1217 #endif // PROJ_DEBUG_NOSEAMBLEED
1218
1219
1220 /* Converts a UV location to a 3D screenspace location
1221  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1222  *
1223  * This is used for finding a pixels location in screenspace for painting */
1224 static void screen_px_from_ortho(
1225         const float uv[2],
1226         const float v1co[3], const float v2co[3], const float v3co[3],  /* Screenspace coords */
1227         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1228         float pixelScreenCo[4],
1229         float w[3])
1230 {
1231         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1232         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1233 }
1234
1235 /* same as screen_px_from_ortho except we
1236  * do perspective correction on the pixel coordinate */
1237 static void screen_px_from_persp(
1238         const float uv[2],
1239         const float v1co[4], const float v2co[4], const float v3co[4],  /* screenspace coords */
1240         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1241         float pixelScreenCo[4],
1242         float w[3])
1243 {
1244         float w_int[3];
1245         float wtot_inv, wtot;
1246         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1247
1248         /* re-weight from the 4th coord of each screen vert */
1249         w_int[0] = w[0] * v1co[3];
1250         w_int[1] = w[1] * v2co[3];
1251         w_int[2] = w[2] * v3co[3];
1252
1253         wtot = w_int[0] + w_int[1] + w_int[2];
1254
1255         if (wtot > 0.0f) {
1256                 wtot_inv = 1.0f / wtot;
1257                 w_int[0] *= wtot_inv;
1258                 w_int[1] *= wtot_inv;
1259                 w_int[2] *= wtot_inv;
1260         }
1261         else {
1262                 w[0] = w[1] = w[2] =
1263                 w_int[0] = w_int[1] = w_int[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1264         }
1265         /* done re-weighting */
1266
1267         /* do interpolation based on projected weight */
1268         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w_int);
1269 }
1270
1271
1272 /**
1273  * Set a direction vector based on a screen location.
1274  * (use for perspective view, else we can simply use `ps->viewDir`)
1275  *
1276  * Similar functionality to #ED_view3d_win_to_vector
1277  *
1278  * \param r_dir: Resulting direction (length is undefined).
1279  */
1280 static void screen_px_to_vector_persp(
1281         int winx, int winy, const float projmat_inv[4][4], const float view_pos[3],
1282         const float co_px[2],
1283         float r_dir[3])
1284 {
1285         r_dir[0] = 2.0f * (co_px[0] / winx) - 1.0f;
1286         r_dir[1] = 2.0f * (co_px[1] / winy) - 1.0f;
1287         r_dir[2] = -0.5f;
1288         mul_project_m4_v3((float(*)[4])projmat_inv, r_dir);
1289         sub_v3_v3(r_dir, view_pos);
1290 }
1291
1292 /**
1293  * Special function to return the factor to a point along a line in pixel space.
1294  *
1295  * This is needed since we can't use #line_point_factor_v2 for perspective screen-space coords.
1296  *
1297  * \param p: 2D screen-space location.
1298  * \param v1, v2: 3D object-space locations.
1299  */
1300 static float screen_px_line_point_factor_v2_persp(
1301         const ProjPaintState *ps,
1302         const float p[2],
1303         const float v1[3], const float v2[3])
1304 {
1305         const float zero[3] = {0};
1306         float v1_proj[3], v2_proj[3];
1307         float dir[3];
1308
1309         screen_px_to_vector_persp(ps->winx, ps->winy, ps->projectMatInv, ps->viewPos, p, dir);
1310
1311         sub_v3_v3v3(v1_proj, v1, ps->viewPos);
1312         sub_v3_v3v3(v2_proj, v2, ps->viewPos);
1313
1314         project_plane_v3_v3v3(v1_proj, v1_proj, dir);
1315         project_plane_v3_v3v3(v2_proj, v2_proj, dir);
1316
1317         return line_point_factor_v2(zero, v1_proj, v2_proj);
1318 }
1319
1320
1321 static void project_face_pixel(
1322         const float *lt_tri_uv[3], ImBuf *ibuf_other, const float w[3],
1323         unsigned char rgba_ub[4], float rgba_f[4])
1324 {
1325         float uv_other[2], x, y;
1326
1327         interp_v2_v2v2v2(uv_other, UNPACK3(lt_tri_uv), w);
1328
1329         /* use */
1330         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1331
1332         if (ibuf_other->rect_float) { /* from float to float */
1333                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1334         }
1335         else { /* from char to float */
1336                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1337         }
1338
1339 }
1340
1341 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1342 static float project_paint_uvpixel_mask(
1343         const ProjPaintState *ps,
1344         const int tri_index,
1345         const float w[3])
1346 {
1347         float mask;
1348
1349         /* Image Mask */
1350         if (ps->do_layer_stencil) {
1351                 /* another UV maps image is masking this one's */
1352                 ImBuf *ibuf_other;
1353                 Image *other_tpage = ps->stencil_ima;
1354
1355                 if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1356                         const MLoopTri *lt_other = &ps->mlooptri_eval[tri_index];
1357                         const float *lt_other_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->poly_to_loop_uv, lt_other) };
1358
1359                         /* BKE_image_acquire_ibuf - TODO - this may be slow */
1360                         unsigned char rgba_ub[4];
1361                         float rgba_f[4];
1362
1363                         project_face_pixel(lt_other_tri_uv, ibuf_other, w, rgba_ub, rgba_f);
1364
1365                         if (ibuf_other->rect_float) { /* from float to float */
1366                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) * (1.0f / 3.0f)) * rgba_f[3];
1367                         }
1368                         else { /* from char to float */
1369                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) * (1.0f / (255.0f * 3.0f))) * (rgba_ub[3] * (1.0f / 255.0f));
1370                         }
1371
1372                         BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1373
1374                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1375                                 mask = (1.0f - mask);
1376
1377                         if (mask == 0.0f) {
1378                                 return 0.0f;
1379                         }
1380                 }
1381                 else {
1382                         return 0.0f;
1383                 }
1384         }
1385         else {
1386                 mask = 1.0f;
1387         }
1388
1389         if (ps->do_mask_cavity) {
1390                 const MLoopTri *lt = &ps->mlooptri_eval[tri_index];
1391                 const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
1392                 float ca1, ca2, ca3, ca_mask;
1393                 ca1 = ps->cavities[lt_vtri[0]];
1394                 ca2 = ps->cavities[lt_vtri[1]];
1395                 ca3 = ps->cavities[lt_vtri[2]];
1396
1397                 ca_mask = w[0] * ca1 + w[1] * ca2 + w[2] * ca3;
1398                 ca_mask = curvemapping_evaluateF(ps->cavity_curve, 0, ca_mask);
1399                 CLAMP(ca_mask, 0.0f, 1.0f);
1400                 mask *= ca_mask;
1401         }
1402
1403         /* calculate mask */
1404         if (ps->do_mask_normal) {
1405                 const MLoopTri *lt = &ps->mlooptri_eval[tri_index];
1406                 const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
1407                 const MPoly *mp = &ps->mpoly_eval[lt->poly];
1408                 float no[3], angle_cos;
1409
1410                 if (mp->flag & ME_SMOOTH) {
1411                         const short *no1, *no2, *no3;
1412                         no1 = ps->mvert_eval[lt_vtri[0]].no;
1413                         no2 = ps->mvert_eval[lt_vtri[1]].no;
1414                         no3 = ps->mvert_eval[lt_vtri[2]].no;
1415
1416                         no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1417                         no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1418                         no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1419                         normalize_v3(no);
1420                 }
1421                 else {
1422                         /* incase the */
1423 #if 1
1424                         /* normalizing per pixel isn't optimal, we could cache or check ps->*/
1425                         normal_tri_v3(no,
1426                                       ps->mvert_eval[lt_vtri[0]].co,
1427                                       ps->mvert_eval[lt_vtri[1]].co,
1428                                       ps->mvert_eval[lt_vtri[2]].co);
1429 #else
1430                         /* don't use because some modifiers dont have normal data (subsurf for eg) */
1431                         copy_v3_v3(no, (float *)ps->dm->getTessFaceData(ps->dm, tri_index, CD_NORMAL));
1432 #endif
1433                 }
1434
1435                 if (UNLIKELY(ps->is_flip_object)) {
1436                         negate_v3(no);
1437                 }
1438
1439                 /* now we can use the normal as a mask */
1440                 if (ps->is_ortho) {
1441                         angle_cos = dot_v3v3(ps->viewDir, no);
1442                 }
1443                 else {
1444                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1445                         float viewDirPersp[3];
1446                         const float *co1, *co2, *co3;
1447                         co1 = ps->mvert_eval[lt_vtri[0]].co;
1448                         co2 = ps->mvert_eval[lt_vtri[1]].co;
1449                         co3 = ps->mvert_eval[lt_vtri[2]].co;
1450
1451                         /* Get the direction from the viewPoint to the pixel and normalize */
1452                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1453                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1454                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1455                         normalize_v3(viewDirPersp);
1456                         if (UNLIKELY(ps->is_flip_object)) {
1457                                 negate_v3(viewDirPersp);
1458                         }
1459
1460                         angle_cos = dot_v3v3(viewDirPersp, no);
1461                 }
1462
1463                 if (angle_cos <= ps->normal_angle__cos) {
1464                         return 0.0f; /* outsize the normal limit*/
1465                 }
1466                 else if (angle_cos < ps->normal_angle_inner__cos) {
1467                         mask *= (ps->normal_angle - acosf(angle_cos)) / ps->normal_angle_range;
1468                 } /* otherwise no mask normal is needed, were within the limit */
1469         }
1470
1471         /* This only works when the opacity dosnt change while painting, stylus pressure messes with this
1472          * so don't use it. */
1473         // if (ps->is_airbrush == 0) mask *= BKE_brush_alpha_get(ps->brush);
1474
1475         return mask;
1476 }
1477
1478 static int project_paint_pixel_sizeof(const short tool)
1479 {
1480         if ((tool == PAINT_TOOL_CLONE) || (tool == PAINT_TOOL_SMEAR)) {
1481                 return sizeof(ProjPixelClone);
1482         }
1483         else {
1484                 return sizeof(ProjPixel);
1485         }
1486 }
1487
1488 static int project_paint_undo_subtiles(const TileInfo *tinf, int tx, int ty)
1489 {
1490         ProjPaintImage *pjIma = tinf->pjima;
1491         int tile_index = tx + ty * tinf->tile_width;
1492         bool generate_tile = false;
1493
1494         /* double check lock to avoid locking */
1495         if (UNLIKELY(!pjIma->undoRect[tile_index])) {
1496                 if (tinf->lock)
1497                         BLI_spin_lock(tinf->lock);
1498                 if (LIKELY(!pjIma->undoRect[tile_index])) {
1499                         pjIma->undoRect[tile_index] = TILE_PENDING;
1500                         generate_tile = true;
1501                 }
1502                 if (tinf->lock)
1503                         BLI_spin_unlock(tinf->lock);
1504         }
1505
1506
1507         if (generate_tile) {
1508                 ListBase *undo_tiles = ED_image_undo_get_tiles();
1509                 volatile void *undorect;
1510                 if (tinf->masked) {
1511                         undorect = image_undo_push_tile(
1512                                 undo_tiles, pjIma->ima, pjIma->ibuf, tinf->tmpibuf,
1513                                 tx, ty, &pjIma->maskRect[tile_index], &pjIma->valid[tile_index], true, false);
1514                 }
1515                 else {
1516                         undorect = image_undo_push_tile(
1517                                 undo_tiles, pjIma->ima, pjIma->ibuf, tinf->tmpibuf,
1518                                 tx, ty, NULL, &pjIma->valid[tile_index], true, false);
1519                 }
1520
1521                 pjIma->ibuf->userflags |= IB_BITMAPDIRTY;
1522                 /* tile ready, publish */
1523                 if (tinf->lock)
1524                         BLI_spin_lock(tinf->lock);
1525                 pjIma->undoRect[tile_index] = undorect;
1526                 if (tinf->lock)
1527                         BLI_spin_unlock(tinf->lock);
1528
1529         }
1530
1531         return tile_index;
1532 }
1533
1534 /* run this function when we know a bucket's, face's pixel can be initialized,
1535  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1536 static ProjPixel *project_paint_uvpixel_init(
1537         const ProjPaintState *ps,
1538         MemArena *arena,
1539         const TileInfo *tinf,
1540         int x_px, int y_px,
1541         const float mask,
1542         const int tri_index,
1543         const float pixelScreenCo[4],
1544         const float world_spaceCo[3],
1545         const float w[3])
1546 {
1547         ProjPixel *projPixel;
1548         int x_tile, y_tile;
1549         int x_round, y_round;
1550         int tile_offset;
1551         /* volatile is important here to ensure pending check is not optimized away by compiler*/
1552         volatile int tile_index;
1553
1554         ProjPaintImage *projima = tinf->pjima;
1555         ImBuf *ibuf = projima->ibuf;
1556         /* wrap pixel location */
1557
1558         x_px = mod_i(x_px, ibuf->x);
1559         y_px = mod_i(y_px, ibuf->y);
1560
1561         BLI_assert(ps->pixel_sizeof == project_paint_pixel_sizeof(ps->tool));
1562         projPixel = BLI_memarena_alloc(arena, ps->pixel_sizeof);
1563
1564         /* calculate the undo tile offset of the pixel, used to store the original
1565          * pixel color and accumulated mask if any */
1566         x_tile =  x_px >> IMAPAINT_TILE_BITS;
1567         y_tile =  y_px >> IMAPAINT_TILE_BITS;
1568
1569         x_round = x_tile * IMAPAINT_TILE_SIZE;
1570         y_round = y_tile * IMAPAINT_TILE_SIZE;
1571         //memset(projPixel, 0, size);
1572
1573         tile_offset = (x_px - x_round) + (y_px - y_round) * IMAPAINT_TILE_SIZE;
1574         tile_index = project_paint_undo_subtiles(tinf, x_tile, y_tile);
1575
1576         /* other thread may be initializing the tile so wait here */
1577         while (projima->undoRect[tile_index] == TILE_PENDING)
1578                 ;
1579
1580         BLI_assert(tile_index < (IMAPAINT_TILE_NUMBER(ibuf->x) * IMAPAINT_TILE_NUMBER(ibuf->y)));
1581         BLI_assert(tile_offset < (IMAPAINT_TILE_SIZE * IMAPAINT_TILE_SIZE));
1582
1583         projPixel->valid = projima->valid[tile_index];
1584
1585         if (ibuf->rect_float) {
1586                 projPixel->pixel.f_pt = ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1587                 projPixel->origColor.f_pt = (float *)projima->undoRect[tile_index] + 4 * tile_offset;
1588                 zero_v4(projPixel->newColor.f);
1589         }
1590         else {
1591                 projPixel->pixel.ch_pt = (unsigned char *)(ibuf->rect + (x_px + y_px * ibuf->x));
1592                 projPixel->origColor.uint_pt = (unsigned int *)projima->undoRect[tile_index] + tile_offset;
1593                 projPixel->newColor.uint = 0;
1594         }
1595
1596         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1597         if (ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D) {
1598                 copy_v3_v3(projPixel->worldCoSS, world_spaceCo);
1599         }
1600
1601         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1602
1603         projPixel->x_px = x_px;
1604         projPixel->y_px = y_px;
1605
1606         projPixel->mask = (unsigned short)(mask * 65535);
1607         if (ps->do_masking)
1608                 projPixel->mask_accum = projima->maskRect[tile_index] + tile_offset;
1609         else
1610                 projPixel->mask_accum = NULL;
1611
1612         /* which bounding box cell are we in?, needed for undo */
1613         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1614                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1615
1616         /* done with view3d_project_float inline */
1617         if (ps->tool == PAINT_TOOL_CLONE) {
1618                 if (ps->poly_to_loop_uv_clone) {
1619                         ImBuf *ibuf_other;
1620                         Image *other_tpage = project_paint_face_clone_image(ps, tri_index);
1621
1622                         if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1623                                 const MLoopTri *lt_other = &ps->mlooptri_eval[tri_index];
1624                                 const float *lt_other_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->poly_to_loop_uv_clone, lt_other) };
1625
1626                                 /* BKE_image_acquire_ibuf - TODO - this may be slow */
1627
1628                                 if (ibuf->rect_float) {
1629                                         if (ibuf_other->rect_float) { /* from float to float */
1630                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1631                                         }
1632                                         else { /* from char to float */
1633                                                 unsigned char rgba_ub[4];
1634                                                 float rgba[4];
1635                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, rgba_ub, NULL);
1636                                                 if (ps->use_colormanagement) {
1637                                                         srgb_to_linearrgb_uchar4(rgba, rgba_ub);
1638                                                 }
1639                                                 else {
1640                                                         rgba_uchar_to_float(rgba, rgba_ub);
1641                                                 }
1642                                                 straight_to_premul_v4_v4(((ProjPixelClone *)projPixel)->clonepx.f, rgba);
1643                                         }
1644                                 }
1645                                 else {
1646                                         if (ibuf_other->rect_float) { /* float to char */
1647                                                 float rgba[4];
1648                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, NULL, rgba);
1649                                                 premul_to_straight_v4(rgba);
1650                                                 if (ps->use_colormanagement) {
1651                                                         linearrgb_to_srgb_uchar3(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1652                                                 }
1653                                                 else {
1654                                                         rgb_float_to_uchar(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1655                                                 }
1656                                                 ((ProjPixelClone *)projPixel)->clonepx.ch[3] =  rgba[3] * 255;
1657                                         }
1658                                         else { /* char to char */
1659                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1660                                         }
1661                                 }
1662
1663                                 BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1664                         }
1665                         else {
1666                                 if (ibuf->rect_float) {
1667                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1668                                 }
1669                                 else {
1670                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1671                                 }
1672                         }
1673
1674                 }
1675                 else {
1676                         float co[2];
1677                         sub_v2_v2v2(co, projPixel->projCoSS, ps->cloneOffset);
1678
1679                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1680                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1681                         if (ibuf->rect_float) {
1682                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1683                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1684                                 }
1685                         }
1686                         else {
1687                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1688                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1689                                 }
1690                         }
1691                 }
1692         }
1693
1694 #ifdef PROJ_DEBUG_PAINT
1695         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1696         else                  projPixel->pixel.ch_pt[0] = 0;
1697 #endif
1698         /* pointer arithmetics */
1699         projPixel->image_index = projima - ps->projImages;
1700
1701         return projPixel;
1702 }
1703
1704 static bool line_clip_rect2f(
1705         const rctf *cliprect,
1706         const rctf *rect,
1707         const float l1[2], const float l2[2],
1708         float l1_clip[2], float l2_clip[2])
1709 {
1710         /* first account for horizontal, then vertical lines */
1711         /* horiz */
1712         if (fabsf(l1[1] - l2[1]) < PROJ_PIXEL_TOLERANCE) {
1713                 /* is the line out of range on its Y axis? */
1714                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1715                         return 0;
1716                 }
1717                 /* line is out of range on its X axis */
1718                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1719                         return 0;
1720                 }
1721
1722
1723                 if (fabsf(l1[0] - l2[0]) < PROJ_PIXEL_TOLERANCE) { /* this is a single point  (or close to)*/
1724                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1725                                 copy_v2_v2(l1_clip, l1);
1726                                 copy_v2_v2(l2_clip, l2);
1727                                 return 1;
1728                         }
1729                         else {
1730                                 return 0;
1731                         }
1732                 }
1733
1734                 copy_v2_v2(l1_clip, l1);
1735                 copy_v2_v2(l2_clip, l2);
1736                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1737                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1738                 return 1;
1739         }
1740         else if (fabsf(l1[0] - l2[0]) < PROJ_PIXEL_TOLERANCE) {
1741                 /* is the line out of range on its X axis? */
1742                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1743                         return 0;
1744                 }
1745
1746                 /* line is out of range on its Y axis */
1747                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1748                         return 0;
1749                 }
1750
1751                 if (fabsf(l1[1] - l2[1]) < PROJ_PIXEL_TOLERANCE) { /* this is a single point  (or close to)*/
1752                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1753                                 copy_v2_v2(l1_clip, l1);
1754                                 copy_v2_v2(l2_clip, l2);
1755                                 return 1;
1756                         }
1757                         else {
1758                                 return 0;
1759                         }
1760                 }
1761
1762                 copy_v2_v2(l1_clip, l1);
1763                 copy_v2_v2(l2_clip, l2);
1764                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1765                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1766                 return 1;
1767         }
1768         else {
1769                 float isect;
1770                 short ok1 = 0;
1771                 short ok2 = 0;
1772
1773                 /* Done with vertical lines */
1774
1775                 /* are either of the points inside the rectangle ? */
1776                 if (BLI_rctf_isect_pt_v(rect, l1)) {
1777                         copy_v2_v2(l1_clip, l1);
1778                         ok1 = 1;
1779                 }
1780
1781                 if (BLI_rctf_isect_pt_v(rect, l2)) {
1782                         copy_v2_v2(l2_clip, l2);
1783                         ok2 = 1;
1784                 }
1785
1786                 /* line inside rect */
1787                 if (ok1 && ok2) return 1;
1788
1789                 /* top/bottom */
1790                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= cliprect->xmin) && (isect <= cliprect->xmax)) {
1791                         if (l1[1] < l2[1]) { /* line 1 is outside */
1792                                 l1_clip[0] = isect;
1793                                 l1_clip[1] = rect->ymin;
1794                                 ok1 = 1;
1795                         }
1796                         else {
1797                                 l2_clip[0] = isect;
1798                                 l2_clip[1] = rect->ymin;
1799                                 ok2 = 2;
1800                         }
1801                 }
1802
1803                 if (ok1 && ok2) return 1;
1804
1805                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= cliprect->xmin) && (isect <= cliprect->xmax)) {
1806                         if (l1[1] > l2[1]) { /* line 1 is outside */
1807                                 l1_clip[0] = isect;
1808                                 l1_clip[1] = rect->ymax;
1809                                 ok1 = 1;
1810                         }
1811                         else {
1812                                 l2_clip[0] = isect;
1813                                 l2_clip[1] = rect->ymax;
1814                                 ok2 = 2;
1815                         }
1816                 }
1817
1818                 if (ok1 && ok2) return 1;
1819
1820                 /* left/right */
1821                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= cliprect->ymin) && (isect <= cliprect->ymax)) {
1822                         if (l1[0] < l2[0]) { /* line 1 is outside */
1823                                 l1_clip[0] = rect->xmin;
1824                                 l1_clip[1] = isect;
1825                                 ok1 = 1;
1826                         }
1827                         else {
1828                                 l2_clip[0] = rect->xmin;
1829                                 l2_clip[1] = isect;
1830                                 ok2 = 2;
1831                         }
1832                 }
1833
1834                 if (ok1 && ok2) return 1;
1835
1836                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= cliprect->ymin) && (isect <= cliprect->ymax)) {
1837                         if (l1[0] > l2[0]) { /* line 1 is outside */
1838                                 l1_clip[0] = rect->xmax;
1839                                 l1_clip[1] = isect;
1840                                 ok1 = 1;
1841                         }
1842                         else {
1843                                 l2_clip[0] = rect->xmax;
1844                                 l2_clip[1] = isect;
1845                                 ok2 = 2;
1846                         }
1847                 }
1848
1849                 if (ok1 && ok2) {
1850                         return 1;
1851                 }
1852                 else {
1853                         return 0;
1854                 }
1855         }
1856 }
1857
1858
1859
1860 /**
1861  * Scale the tri about its center
1862  * scaling by #PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1863  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces
1864  */
1865 #ifndef PROJ_DEBUG_NOSEAMBLEED
1866
1867 static void scale_tri(float insetCos[3][3], const float *origCos[4], const float inset)
1868 {
1869         float cent[3];
1870         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) * (1.0f / 3.0f);
1871         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) * (1.0f / 3.0f);
1872         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) * (1.0f / 3.0f);
1873
1874         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1875         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1876         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1877
1878         mul_v3_fl(insetCos[0], inset);
1879         mul_v3_fl(insetCos[1], inset);
1880         mul_v3_fl(insetCos[2], inset);
1881
1882         add_v3_v3(insetCos[0], cent);
1883         add_v3_v3(insetCos[1], cent);
1884         add_v3_v3(insetCos[2], cent);
1885 }
1886 #endif //PROJ_DEBUG_NOSEAMBLEED
1887
1888 static float len_squared_v2v2_alt(const float v1[2], const float v2_1, const float v2_2)
1889 {
1890         float x, y;
1891
1892         x = v1[0] - v2_1;
1893         y = v1[1] - v2_2;
1894         return x * x + y * y;
1895 }
1896
1897 /* note, use a squared value so we can use len_squared_v2v2
1898  * be sure that you have done a bounds check first or this may fail */
1899 /* only give bucket_bounds as an arg because we need it elsewhere */
1900 static bool project_bucket_isect_circle(const float cent[2], const float radius_squared, const rctf *bucket_bounds)
1901 {
1902
1903         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect
1904          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1905          * this is even less work then an intersection test
1906          */
1907 #if 0
1908         if (BLI_rctf_isect_pt_v(bucket_bounds, cent))
1909                 return 1;
1910 #endif
1911
1912         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1913             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1914         {
1915                 return 1;
1916         }
1917
1918         /* out of bounds left */
1919         if (cent[0] < bucket_bounds->xmin) {
1920                 /* lower left out of radius test */
1921                 if (cent[1] < bucket_bounds->ymin) {
1922                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1923                 }
1924                 /* top left test */
1925                 else if (cent[1] > bucket_bounds->ymax) {
1926                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1927                 }
1928         }
1929         else if (cent[0] > bucket_bounds->xmax) {
1930                 /* lower right out of radius test */
1931                 if (cent[1] < bucket_bounds->ymin) {
1932                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1933                 }
1934                 /* top right test */
1935                 else if (cent[1] > bucket_bounds->ymax) {
1936                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1937                 }
1938         }
1939
1940         return 0;
1941 }
1942
1943
1944
1945 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1946  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1947  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1948  * (viewed from the side)
1949  *
1950  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1951  * funcs that only account for points inside the triangle.
1952  * however switching back to this for ortho is always an option */
1953
1954 static void rect_to_uvspace_ortho(
1955         const rctf *bucket_bounds,
1956         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1957         const float *uv1co, const float *uv2co, const float *uv3co,
1958         float bucket_bounds_uv[4][2],
1959         const int flip)
1960 {
1961         float uv[2];
1962         float w[3];
1963
1964         /* get the UV space bounding box */
1965         uv[0] = bucket_bounds->xmax;
1966         uv[1] = bucket_bounds->ymin;
1967         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1968         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1969
1970         //uv[0] = bucket_bounds->xmax; // set above
1971         uv[1] = bucket_bounds->ymax;
1972         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1973         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1974
1975         uv[0] = bucket_bounds->xmin;
1976         //uv[1] = bucket_bounds->ymax; // set above
1977         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1978         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1979
1980         //uv[0] = bucket_bounds->xmin; // set above
1981         uv[1] = bucket_bounds->ymin;
1982         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1983         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1984 }
1985
1986 /* same as above but use barycentric_weights_v2_persp */
1987 static void rect_to_uvspace_persp(
1988         const rctf *bucket_bounds,
1989         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1990         const float *uv1co, const float *uv2co, const float *uv3co,
1991         float bucket_bounds_uv[4][2],
1992         const int flip
1993         )
1994 {
1995         float uv[2];
1996         float w[3];
1997
1998         /* get the UV space bounding box */
1999         uv[0] = bucket_bounds->xmax;
2000         uv[1] = bucket_bounds->ymin;
2001         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2002         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
2003
2004         //uv[0] = bucket_bounds->xmax; // set above
2005         uv[1] = bucket_bounds->ymax;
2006         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2007         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
2008
2009         uv[0] = bucket_bounds->xmin;
2010         //uv[1] = bucket_bounds->ymax; // set above
2011         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2012         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
2013
2014         //uv[0] = bucket_bounds->xmin; // set above
2015         uv[1] = bucket_bounds->ymin;
2016         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2017         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
2018 }
2019
2020 /* This works as we need it to but we can save a few steps and not use it */
2021
2022 #if 0
2023 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
2024 {
2025         float v1[2], v2[2];
2026
2027         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
2028         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
2029
2030         return -atan2f(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
2031 }
2032 #endif
2033
2034 #define ISECT_1 (1)
2035 #define ISECT_2 (1 << 1)
2036 #define ISECT_3 (1 << 2)
2037 #define ISECT_4 (1 << 3)
2038 #define ISECT_ALL3 ((1 << 3) - 1)
2039 #define ISECT_ALL4 ((1 << 4) - 1)
2040
2041 /* limit must be a fraction over 1.0f */
2042 static bool IsectPT2Df_limit(
2043         const float pt[2],
2044         const float v1[2], const float v2[2], const float v3[2],
2045         const float limit)
2046 {
2047         return ((area_tri_v2(pt, v1, v2) +
2048                  area_tri_v2(pt, v2, v3) +
2049                  area_tri_v2(pt, v3, v1)) / (area_tri_v2(v1, v2, v3))) < limit;
2050 }
2051
2052 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
2053  * so we have the clipped UV's to do pixel intersection tests with
2054  * */
2055 static int float_z_sort_flip(const void *p1, const void *p2)
2056 {
2057         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
2058 }
2059
2060 static int float_z_sort(const void *p1, const void *p2)
2061 {
2062         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
2063 }
2064
2065 /* assumes one point is within the rectangle */
2066 static bool line_rect_clip(
2067         const rctf *rect,
2068         const float l1[4], const float l2[4],
2069         const float uv1[2], const float uv2[2],
2070         float uv[2], bool is_ortho)
2071 {
2072         float min = FLT_MAX, tmp;
2073         float xlen = l2[0] - l1[0];
2074         float ylen = l2[1] - l1[1];
2075
2076         /* 0.1 might seem too much, but remember, this is pixels! */
2077         if (xlen > 0.1f) {
2078                 if ((l1[0] - rect->xmin) * (l2[0] - rect->xmin) <= 0) {
2079                         tmp = rect->xmin;
2080                         min = min_ff((tmp - l1[0]) / xlen, min);
2081                 }
2082                 else if ((l1[0] - rect->xmax) * (l2[0] - rect->xmax) < 0) {
2083                         tmp = rect->xmax;
2084                         min = min_ff((tmp - l1[0]) / xlen, min);
2085                 }
2086         }
2087
2088         if (ylen > 0.1f) {
2089                 if ((l1[1] - rect->ymin) * (l2[1] - rect->ymin) <= 0) {
2090                         tmp = rect->ymin;
2091                         min = min_ff((tmp - l1[1]) / ylen, min);
2092                 }
2093                 else if ((l1[1] - rect->ymax) * (l2[1] - rect->ymax) < 0) {
2094                         tmp = rect->ymax;
2095                         min = min_ff((tmp - l1[1]) / ylen, min);
2096                 }
2097         }
2098
2099         if (min == FLT_MAX)
2100                 return false;
2101
2102         tmp = (is_ortho) ? 1.0f : (l1[3] + min * (l2[3] - l1[3]));
2103
2104         uv[0] = (uv1[0] + min / tmp * (uv2[0] - uv1[0]));
2105         uv[1] = (uv1[1] + min / tmp * (uv2[1] - uv1[1]));
2106
2107         return true;
2108 }
2109
2110
2111 static void project_bucket_clip_face(
2112         const bool is_ortho, const bool is_flip_object,
2113         const rctf *cliprect,
2114         const rctf *bucket_bounds,
2115         const float *v1coSS, const float *v2coSS, const float *v3coSS,
2116         const float *uv1co, const float *uv2co, const float *uv3co,
2117         float bucket_bounds_uv[8][2],
2118         int *tot, bool cull)
2119 {
2120         int inside_bucket_flag = 0;
2121         int inside_face_flag = 0;
2122         int flip;
2123         bool collinear = false;
2124
2125         float bucket_bounds_ss[4][2];
2126
2127         /* detect pathological case where face the three vertices are almost collinear in screen space.
2128          * mostly those will be culled but when flood filling or with smooth shading it's a possibility */
2129         if (min_fff(dist_squared_to_line_v2(v1coSS, v2coSS, v3coSS),
2130                     dist_squared_to_line_v2(v2coSS, v3coSS, v1coSS),
2131                     dist_squared_to_line_v2(v3coSS, v1coSS, v2coSS)) < PROJ_PIXEL_TOLERANCE)
2132         {
2133                 collinear = true;
2134         }
2135
2136         /* get the UV space bounding box */
2137         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v1coSS);
2138         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v2coSS) << 1;
2139         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v3coSS) << 2;
2140
2141         if (inside_bucket_flag == ISECT_ALL3) {
2142                 /* is_flip_object is used here because we use the face winding */
2143                 flip = (((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != is_flip_object) !=
2144                         (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
2145
2146                 /* all screenspace points are inside the bucket bounding box,
2147                  * this means we don't need to clip and can simply return the UVs */
2148                 if (flip) { /* facing the back? */
2149                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
2150                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2151                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
2152                 }
2153                 else {
2154                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
2155                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2156                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
2157                 }
2158
2159                 *tot = 3;
2160                 return;
2161         }
2162         /* handle pathological case here, no need for further intersections below since tringle area is almost zero */
2163         if (collinear) {
2164                 int flag;
2165
2166                 (*tot) = 0;
2167
2168                 if (cull)
2169                         return;
2170
2171                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(bucket_bounds_uv[*tot], uv1co); (*tot)++; }
2172
2173                 flag = inside_bucket_flag & (ISECT_1 | ISECT_2);
2174                 if (flag && flag != (ISECT_1 | ISECT_2)) {
2175                         if (line_rect_clip(bucket_bounds, v1coSS, v2coSS, uv1co, uv2co, bucket_bounds_uv[*tot], is_ortho))
2176                                 (*tot)++;
2177                 }
2178
2179                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(bucket_bounds_uv[*tot], uv2co); (*tot)++; }
2180
2181                 flag = inside_bucket_flag & (ISECT_2 | ISECT_3);
2182                 if (flag && flag != (ISECT_2 | ISECT_3)) {
2183                         if (line_rect_clip(bucket_bounds, v2coSS, v3coSS, uv2co, uv3co, bucket_bounds_uv[*tot], is_ortho))
2184                                 (*tot)++;
2185                 }
2186
2187                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(bucket_bounds_uv[*tot], uv3co); (*tot)++; }
2188
2189                 flag = inside_bucket_flag & (ISECT_3 | ISECT_1);
2190                 if (flag && flag != (ISECT_3 | ISECT_1)) {
2191                         if (line_rect_clip(bucket_bounds, v3coSS, v1coSS, uv3co, uv1co, bucket_bounds_uv[*tot], is_ortho))
2192                                 (*tot)++;
2193                 }
2194
2195                 if ((*tot) < 3) {
2196                         /* no intersections to speak of, but more probable is that all face is just outside the
2197                          * rectangle and culled due to float precision issues. Since above tests have failed,
2198                          * just dump triangle as is for painting */
2199                         *tot = 0;
2200                         copy_v2_v2(bucket_bounds_uv[*tot], uv1co); (*tot)++;
2201                         copy_v2_v2(bucket_bounds_uv[*tot], uv2co); (*tot)++;
2202                         copy_v2_v2(bucket_bounds_uv[*tot], uv3co); (*tot)++;
2203                         return;
2204                 }
2205
2206                 return;
2207         }
2208
2209         /* get the UV space bounding box */
2210         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
2211         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
2212         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
2213         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
2214
2215         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
2216         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
2217         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
2218
2219         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
2220         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
2221         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
2222
2223         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
2224         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
2225         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
2226
2227         flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) !=
2228                 (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
2229
2230         if (inside_face_flag == ISECT_ALL4) {
2231                 /* bucket is totally inside the screenspace face, we can safely use weights */
2232
2233                 if (is_ortho) {
2234                         rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2235                 }
2236                 else {
2237                         rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2238                 }
2239
2240                 *tot = 4;
2241                 return;
2242         }
2243         else {
2244                 /* The Complicated Case!
2245                  *
2246                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
2247                  *
2248                  * we need to make a convex polyline from the intersection between the screenspace face
2249                  * and the bucket bounds.
2250                  *
2251                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
2252                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
2253                  * do a correct clipping on both shapes. */
2254
2255
2256                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
2257
2258
2259
2260                 /* Maximum possible 6 intersections when using a rectangle and triangle */
2261                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
2262                 float v1_clipSS[2], v2_clipSS[2];
2263                 float w[3];
2264
2265                 /* calc center */
2266                 float cent[2] = {0.0f, 0.0f};
2267                 /*float up[2] = {0.0f, 1.0f};*/
2268                 int i;
2269                 bool doubles;
2270
2271                 (*tot) = 0;
2272
2273                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
2274                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
2275                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
2276                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
2277
2278                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
2279                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
2280                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
2281
2282                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
2283                         if (line_clip_rect2f(cliprect, bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
2284                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2285                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2286                         }
2287                 }
2288
2289                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
2290                         if (line_clip_rect2f(cliprect, bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
2291                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2292                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2293                         }
2294                 }
2295
2296                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
2297                         if (line_clip_rect2f(cliprect, bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
2298                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2299                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2300                         }
2301                 }
2302
2303
2304                 if ((*tot) < 3) { /* no intersections to speak of */
2305                         *tot = 0;
2306                         return;
2307                 }
2308
2309                 /* now we have all points we need, collect their angles and sort them clockwise */
2310
2311                 for (i = 0; i < (*tot); i++) {
2312                         cent[0] += isectVCosSS[i][0];
2313                         cent[1] += isectVCosSS[i][1];
2314                 }
2315                 cent[0] = cent[0] / (float)(*tot);
2316                 cent[1] = cent[1] / (float)(*tot);
2317
2318
2319
2320                 /* Collect angles for every point around the center point */
2321
2322
2323 #if 0   /* uses a few more cycles then the above loop */
2324                 for (i = 0; i < (*tot); i++) {
2325                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
2326                 }
2327 #endif
2328
2329                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
2330                 v1_clipSS[1] = cent[1] + 1.0f;
2331
2332                 for (i = 0; i < (*tot); i++) {
2333                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2334                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2335                         isectVCosSS[i][2] = atan2f(v1_clipSS[0] * v2_clipSS[1] - v1_clipSS[1] * v2_clipSS[0],
2336                                                    v1_clipSS[0] * v2_clipSS[0] + v1_clipSS[1] * v2_clipSS[1]);
2337                 }
2338
2339                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
2340                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
2341
2342                 doubles = true;
2343                 while (doubles == true) {
2344                         doubles = false;
2345
2346                         for (i = 0; i < (*tot); i++) {
2347                                 if (fabsf(isectVCosSS[(i + 1) % *tot][0] - isectVCosSS[i][0]) < PROJ_PIXEL_TOLERANCE &&
2348                                     fabsf(isectVCosSS[(i + 1) % *tot][1] - isectVCosSS[i][1]) < PROJ_PIXEL_TOLERANCE)
2349                                 {
2350                                         int j;
2351                                         for (j = i; j < (*tot) - 1; j++) {
2352                                                 isectVCosSS[j][0] = isectVCosSS[j + 1][0];
2353                                                 isectVCosSS[j][1] = isectVCosSS[j + 1][1];
2354                                         }
2355                                         doubles = true; /* keep looking for more doubles */
2356                                         (*tot)--;
2357                                 }
2358                         }
2359
2360                         /* its possible there is only a few left after remove doubles */
2361                         if ((*tot) < 3) {
2362                                 // printf("removed too many doubles B\n");
2363                                 *tot = 0;
2364                                 return;
2365                         }
2366                 }
2367
2368                 if (is_ortho) {
2369                         for (i = 0; i < (*tot); i++) {
2370                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2371                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2372                         }
2373                 }
2374                 else {
2375                         for (i = 0; i < (*tot); i++) {
2376                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2377                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2378                         }
2379                 }
2380         }
2381
2382 #ifdef PROJ_DEBUG_PRINT_CLIP
2383         /* include this at the bottom of the above function to debug the output */
2384
2385         {
2386                 /* If there are ever any problems, */
2387                 float test_uv[4][2];
2388                 int i;
2389                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2390                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2391                 printf("(  [(%f,%f), (%f,%f), (%f,%f), (%f,%f)], ",
2392                        test_uv[0][0], test_uv[0][1],   test_uv[1][0], test_uv[1][1],
2393                        test_uv[2][0], test_uv[2][1],    test_uv[3][0], test_uv[3][1]);
2394
2395                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2396
2397                 printf("[");
2398                 for (i = 0; i < (*tot); i++) {
2399                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2400                 }
2401                 printf("]),\\\n");
2402         }
2403 #endif
2404 }
2405
2406 /*
2407  * # This script creates faces in a blender scene from printed data above.
2408  *
2409  * project_ls = [
2410  * ...(output from above block)...
2411  * ]
2412  *
2413  * from Blender import Scene, Mesh, Window, sys, Mathutils
2414  *
2415  * import bpy
2416  *
2417  * V = Mathutils.Vector
2418  *
2419  * def main():
2420  *     sce = bpy.data.scenes.active
2421  *
2422  *     for item in project_ls:
2423  *         bb = item[0]
2424  *         uv = item[1]
2425  *         poly = item[2]
2426  *
2427  *         me = bpy.data.meshes.new()
2428  *         ob = sce.objects.new(me)
2429  *
2430  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2431  *         me.faces.extend([(0,1,2,3),])
2432  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2433  *         me.faces.extend([(4,5,6),])
2434  *
2435  *         vs = [V(p).xyz for p in poly]
2436  *         print len(vs)
2437  *         l = len(me.verts)
2438  *         me.verts.extend(vs)
2439  *
2440  *         i = l
2441  *         while i < len(me.verts):
2442  *             ii = i + 1
2443  *             if ii == len(me.verts):
2444  *                 ii = l
2445  *             me.edges.extend([i, ii])
2446  *             i += 1
2447  *
2448  * if __name__ == '__main__':
2449  *     main()
2450  */
2451
2452
2453 #undef ISECT_1
2454 #undef ISECT_2
2455 #undef ISECT_3
2456 #undef ISECT_4
2457 #undef ISECT_ALL3
2458 #undef ISECT_ALL4
2459
2460
2461 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2462  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2463 static bool IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2464 {
2465         int i;
2466         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2467                 return 0;
2468
2469         for (i = 1; i < tot; i++) {
2470                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2471                         return 0;
2472
2473         }
2474
2475         return 1;
2476 }
2477 static bool IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2478 {
2479         int i;
2480         bool side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2481
2482         for (i = 1; i < tot; i++) {
2483                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2484                         return 0;
2485
2486         }
2487
2488         return 1;
2489 }
2490
2491 /* One of the most important function for projection painting,
2492  * since it selects the pixels to be added into each bucket.
2493  *
2494  * initialize pixels from this face where it intersects with the bucket_index,
2495  * optionally initialize pixels for removing seams */
2496 static void project_paint_face_init(
2497         const ProjPaintState *ps,
2498         const int thread_index, const int bucket_index, const int tri_index, const int image_index,
2499         const rctf *clip_rect, const rctf *bucket_bounds, ImBuf *ibuf, ImBuf **tmpibuf)
2500 {
2501         /* Projection vars, to get the 3D locations into screen space  */
2502         MemArena *arena = ps->arena_mt[thread_index];
2503         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2504         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2505         bool threaded = (ps->thread_tot > 1);
2506
2507         TileInfo tinf = {
2508                 ps->tile_lock,
2509                 ps->do_masking,
2510                 IMAPAINT_TILE_NUMBER(ibuf->x),
2511                 tmpibuf,
2512                 ps->projImages + image_index
2513         };
2514
2515         const MLoopTri *lt = &ps->mlooptri_eval[tri_index];
2516         const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
2517         const float *lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->poly_to_loop_uv, lt) };
2518
2519         /* UV/pixel seeking data */
2520         int x; /* Image X-Pixel */
2521         int y; /* Image Y-Pixel */
2522         float mask;
2523         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2524
2525         const float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to lt_vtri[0-2] */
2526
2527         const float *vCo[3]; /* vertex screenspace coords */
2528
2529         float w[3], wco[3];
2530
2531         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 */
2532         float pixelScreenCo[4];
2533         bool do_3d_mapping = ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D;
2534
2535         rcti bounds_px; /* ispace bounds */
2536         /* vars for getting uvspace bounds */
2537
2538         float lt_uv_pxoffset[3][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2539         float xhalfpx, yhalfpx;
2540         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2541
2542         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2543
2544         float uv_clip[8][2];
2545         int uv_clip_tot;
2546         const bool is_ortho = ps->is_ortho;
2547         const bool is_flip_object = ps->is_flip_object;
2548         const bool do_backfacecull = ps->do_backfacecull;
2549         const bool do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2550
2551         vCo[0] = ps->mvert_eval[lt_vtri[0]].co;
2552         vCo[1] = ps->mvert_eval[lt_vtri[1]].co;
2553         vCo[2] = ps->mvert_eval[lt_vtri[2]].co;
2554
2555
2556         /* Use lt_uv_pxoffset instead of lt_tri_uv so we can offset the UV half a pixel
2557          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2558          * problems when wrapping negative coords */
2559         xhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 3.0f))) / ibuf_xf;
2560         yhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 4.0f))) / ibuf_yf;
2561
2562         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2563          * Needed to add this offset since UV coords are often quads aligned to pixels.
2564          * In this case pixels can be exactly between 2 triangles causing nasty
2565          * artifacts.
2566          *
2567          * This workaround can be removed and painting will still work on most cases
2568          * but since the first thing most people try is painting onto a quad- better make it work.
2569          */
2570
2571         lt_uv_pxoffset[0][0] = lt_tri_uv[0][0] - xhalfpx;
2572         lt_uv_pxoffset[0][1] = lt_tri_uv[0][1] - yhalfpx;
2573
2574         lt_uv_pxoffset[1][0] = lt_tri_uv[1][0] - xhalfpx;
2575         lt_uv_pxoffset[1][1] = lt_tri_uv[1][1] - yhalfpx;
2576
2577         lt_uv_pxoffset[2][0] = lt_tri_uv[2][0] - xhalfpx;
2578         lt_uv_pxoffset[2][1] = lt_tri_uv[2][1] - yhalfpx;
2579
2580         {
2581                 uv1co = lt_uv_pxoffset[0]; // was lt_tri_uv[i1];
2582                 uv2co = lt_uv_pxoffset[1]; // was lt_tri_uv[i2];
2583                 uv3co = lt_uv_pxoffset[2]; // was lt_tri_uv[i3];
2584
2585                 v1coSS = ps->screenCoords[lt_vtri[0]];
2586                 v2coSS = ps->screenCoords[lt_vtri[1]];
2587                 v3coSS = ps->screenCoords[lt_vtri[2]];
2588
2589                 /* This funtion gives is a concave polyline in UV space from the clipped tri*/
2590                 project_bucket_clip_face(
2591                         is_ortho, is_flip_object,
2592                         clip_rect, bucket_bounds,
2593                         v1coSS, v2coSS, v3coSS,
2594                         uv1co, uv2co, uv3co,
2595                         uv_clip, &uv_clip_tot,
2596                         do_backfacecull || ps->do_occlude);
2597
2598                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2599 #if 0
2600                 if (uv_clip_tot > 6) {
2601                         printf("this should never happen! %d\n", uv_clip_tot);
2602                 }
2603 #endif
2604
2605                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2606 #if 0
2607                         project_paint_undo_tiles_init(
2608                                 &bounds_px, ps->projImages + image_index, tmpibuf,
2609                                 tile_width, threaded, ps->do_masking);
2610 #endif
2611                         /* clip face and */
2612
2613                         has_isect = 0;
2614                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2615                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2616                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2617
2618                                 has_x_isect = 0;
2619                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2620                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2621                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2622
2623                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2624                                          * could check the poly direction but better to do this */
2625                                         if ((do_backfacecull == true  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2626                                             (do_backfacecull == false && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2627                                         {
2628
2629                                                 has_x_isect = has_isect = 1;
2630
2631                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2632                                                 else screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2633
2634                                                 /* a pity we need to get the worldspace pixel location here */
2635                                                 if (do_clip || do_3d_mapping) {
2636                                                         interp_v3_v3v3v3(
2637                                                                 wco,
2638                                                                 ps->mvert_eval[lt_vtri[0]].co,
2639                                                                 ps->mvert_eval[lt_vtri[1]].co,
2640                                                                 ps->mvert_eval[lt_vtri[2]].co,
2641                                                                 w);
2642                                                         if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2643                                                                 continue; /* Watch out that no code below this needs to run */
2644                                                         }
2645                                                 }
2646
2647                                                 /* Is this UV visible from the view? - raytrace */
2648                                                 /* project_paint_PickFace is less complex, use for testing */
2649                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == tri_index) {
2650                                                 if ((ps->do_occlude == false) ||
2651                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, tri_index, pixelScreenCo))
2652                                                 {
2653                                                         mask = project_paint_uvpixel_mask(ps, tri_index, w);
2654
2655                                                         if (mask > 0.0f) {
2656                                                                 BLI_linklist_prepend_arena(
2657                                                                         bucketPixelNodes,
2658                                                                         project_paint_uvpixel_init(
2659                                                                                 ps, arena, &tinf, x, y, mask, tri_index,
2660                                                                                 pixelScreenCo, wco, w),
2661                                                                         arena);
2662                                                         }
2663                                                 }
2664
2665                                         }
2666 //#if 0
2667                                         else if (has_x_isect) {
2668                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2669                                                 break;
2670                                         }
2671 //#endif
2672                                 }
2673
2674
2675 #if 0           /* TODO - investigate why this dosnt work sometimes! it should! */
2676                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2677                                 if (has_x_isect == 0 && has_isect) {
2678                                         break;
2679                                 }
2680 #endif
2681                         }
2682                 }
2683         }
2684
2685
2686 #ifndef PROJ_DEBUG_NOSEAMBLEED
2687         if (ps->seam_bleed_px > 0.0f) {
2688                 int face_seam_flag;
2689
2690                 if (threaded)
2691                         BLI_thread_lock(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2692
2693                 face_seam_flag = ps->faceSeamFlags[tri_index];
2694
2695                 /* are any of our edges un-initialized? */
2696                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_NOSEAM1)) == 0 ||
2697                     (face_seam_flag & (PROJ_FACE_SEAM2 | PROJ_FACE_NOSEAM2)) == 0 ||
2698                     (face_seam_flag & (PROJ_FACE_SEAM3 | PROJ_FACE_NOSEAM3)) == 0)
2699                 {
2700                         project_face_seams_init(ps, tri_index);
2701                         face_seam_flag = ps->faceSeamFlags[tri_index];
2702                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3);
2703                 }
2704
2705                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_SEAM2 | PROJ_FACE_SEAM3)) == 0) {
2706
2707                         if (threaded)
2708                                 BLI_thread_unlock(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2709
2710                 }
2711                 else {
2712                         /* we have a seam - deal with it! */
2713
2714                         /* Now create new UV's for the seam face */
2715                         float (*outset_uv)[2] = ps->faceSeamUVs[tri_index];
2716                         float insetCos[3][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2717
2718                         const float *vCoSS[3]; /* vertex screenspace coords */
2719
2720                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2721                         float edge_verts_inset_clip[2][3];
2722                         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 */
2723
2724                         float seam_subsection[4][2];
2725                         float fac1, fac2;
2726
2727                         if (outset_uv[0][0] == FLT_MAX) /* first time initialize */
2728                                 uv_image_outset(
2729                                         lt_uv_pxoffset, outset_uv, ps->seam_bleed_px,
2730                                         ibuf->x, ibuf->y, (ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_CW) == 0);
2731
2732                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2733                         if (threaded)
2734                                 BLI_thread_unlock(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2735
2736                         vCoSS[0] = ps->screenCoords[lt_vtri[0]];
2737                         vCoSS[1] = ps->screenCoords[lt_vtri[1]];
2738                         vCoSS[2] = ps->screenCoords[lt_vtri[2]];
2739
2740                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2741                         if (is_ortho) {
2742                                 scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2743                         }
2744                         else {
2745                                 scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2746                         }
2747
2748                         for (fidx1 = 0; fidx1 < 3; fidx1++) {
2749                                 fidx2 = (fidx1 == 2) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2) -> (1,2,0) */
2750
2751                                 if ((face_seam_flag & (1 << fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2752                                     line_clip_rect2f(clip_rect, bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1]))
2753                                 {
2754                                         if (len_squared_v2v2(vCoSS[fidx1], vCoSS[fidx2]) > FLT_EPSILON) { /* avoid div by zero */
2755
2756                                                 if (is_ortho) {
2757                                                         fac1 = line_point_factor_v2(bucket_clip_edges[0], vCoSS[fidx1], vCoSS[fidx2]);
2758                                                         fac2 = line_point_factor_v2(bucket_clip_edges[1], vCoSS[fidx1], vCoSS[fidx2]);
2759                                                 }
2760                                                 else {
2761                                                         fac1 = screen_px_line_point_factor_v2_persp(ps, bucket_clip_edges[0], vCo[fidx1], vCo[fidx2]);
2762                                                         fac2 = screen_px_line_point_factor_v2_persp(ps, bucket_clip_edges[1], vCo[fidx1], vCo[fidx2]);
2763                                                 }
2764
2765                                                 interp_v2_v2v2(seam_subsection[0], lt_uv_pxoffset[fidx1], lt_uv_pxoffset[fidx2], fac1);
2766                                                 interp_v2_v2v2(seam_subsection[1], lt_uv_pxoffset[fidx1], lt_uv_pxoffset[fidx2], fac2);
2767
2768                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2769                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2770
2771                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2772                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2773                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2774                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2775
2776
2777                                                 if (pixel_bounds_uv(seam_subsection, &bounds_px, ibuf->x, ibuf->y)) {
2778                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2779
2780                                                         has_isect = 0;
2781                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2782                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2783                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2784
2785                                                                 has_x_isect = 0;
2786                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2787                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2788                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2789
2790                                                                         /* test we're inside uvspace bucket and triangle bounds */
2791                                                                         if (isect_point_quad_v2(uv, UNPACK4(seam_subsection))) {
2792                                                                                 float fac;
2793
2794                                                                                 /* We need to find the closest point along the face edge,
2795                                                                                  * getting the screen_px_from_*** wont work because our actual location
2796                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2797                                                                                  * our location on the side of the face's UV */
2798 #if 0
2799                                                                                 if (is_ortho) screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2800                                                                                 else          screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2801 #endif
2802
2803                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2804                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2805                                                                                 fac = resolve_quad_u_v2(uv, UNPACK4(seam_subsection));
2806                                                                                 interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac);
2807
2808                                                                                 if (!is_ortho) {
2809                                                                                         pixelScreenCo[3] = 1.0f;
2810                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2811                                                                                         pixelScreenCo[0] = (float)(ps->winx * 0.5f) + (ps->winx * 0.5f) * pixelScreenCo[0] / pixelScreenCo[3];
2812                                                                                         pixelScreenCo[1] = (float)(ps->winy * 0.5f) + (ps->winy * 0.5f) * pixelScreenCo[1] / pixelScreenCo[3];
2813                                                                                         pixelScreenCo[2] = pixelScreenCo[2] / pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2814                                                                                 }
2815
2816                                                                                 if ((ps->do_occlude == false) ||
2817                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, tri_index, pixelScreenCo))
2818                                                                                 {
2819                                                                                         /* Only bother calculating the weights if we intersect */
2820                                                                                         if (ps->do_mask_normal || ps->poly_to_loop_uv_clone) {
2821                                                                                                 const float uv_fac = fac1 + (fac * (fac2 - fac1));
2822 #if 0
2823                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2824                                                                                                 float uv_close[2];
2825                                                                                                 interp_v2_v2v2(uv_close, lt_uv_pxoffset[fidx1], lt_uv_pxoffset[fidx2], uv_fac);
2826                                                                                                 barycentric_weights_v2(lt_uv_pxoffset[0], lt_uv_pxoffset[1], lt_uv_pxoffset[2], uv_close, w);
2827 #else
2828
2829                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2830                                                                                                 w[0] = w[1] = w[2] = 0.0;
2831                                                                                                 w[fidx1] = 1.0f - uv_fac;
2832                                                                                                 w[fidx2] = uv_fac;
2833 #endif
2834                                                                                         }
2835
2836                                                                                         /* a pity we need to get the worldspace pixel location here */
2837                                                                                         if (do_clip || do_3d_mapping) {
2838                                                                                                 interp_v3_v3v3v3(wco, vCo[0], vCo[1], vCo[2], w);
2839
2840                                                                                                 if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2841                                                                                                         continue; /* Watch out that no code below this needs to run */
2842                                                                                                 }
2843                                                                                         }
2844
2845                                                                                         mask = project_paint_uvpixel_mask(ps, tri_index, w);
2846
2847                                                                                         if (mask > 0.0f) {
2848                                                                                                 BLI_linklist_prepend_arena(
2849                                                                                                         bucketPixelNodes,
2850                                                                                                         project_paint_uvpixel_init(ps, arena, &tinf, x, y, mask, tri_index,
2851                                                                                                         pixelScreenCo, wco, w),
2852                                                                                                         arena
2853                                                                                                         );
2854                                                                                         }
2855
2856                                                                                 }
2857                                                                         }
2858                                                                         else if (has_x_isect) {
2859                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2860                                                                                 break;
2861                                                                         }
2862                                                                 }
2863
2864 #if 0                           /* TODO - investigate why this dosnt work sometimes! it should! */
2865                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2866                                                                 if (has_x_isect == 0 && has_isect) {
2867                                                                         break;
2868                                                                 }
2869 #endif
2870                                                         }
2871                                                 }
2872                                         }
2873                                 }
2874                         }
2875                 }
2876         }
2877 #else
2878         UNUSED_VARS(vCo, threaded);
2879 #endif // PROJ_DEBUG_NOSEAMBLEED
2880 }
2881
2882
2883 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2884 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2885 {
2886         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2887         /* 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 */
2888         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 */
2889         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2890
2891         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2892         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2893
2894         /* in case the rect is outside the mesh 2d bounds */
2895         CLAMP(bucketMin[0], 0, ps->buckets_x);
2896         CLAMP(bucketMin[1], 0, ps->buckets_y);
2897
2898         CLAMP(bucketMax[0], 0, ps->buckets_x);
2899         CLAMP(bucketMax[1], 0, ps->buckets_y);
2900 }
2901
2902 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2903 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2904 {
2905         bucket_bounds->xmin = ps->screenMin[0] + ((bucket_x) * (ps->screen_width / ps->buckets_x));     /* left */
2906         bucket_bounds->xmax = ps->screenMin[0] + ((bucket_x + 1) * (ps->screen_width / ps->buckets_x)); /* right */
2907
2908         bucket_bounds->ymin = ps->screenMin[1] + ((bucket_y) * (ps->screen_height / ps->buckets_y));      /* bottom */
2909         bucket_bounds->ymax = ps->screenMin[1] + ((bucket_y + 1) * (ps->screen_height  / ps->buckets_y)); /* top */
2910 }
2911
2912 /* Fill this bucket with pixels from the faces that intersect it.
2913  *
2914  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2915 static void project_bucket_init(
2916         const ProjPaintState *ps, const int thread_index, const int bucket_index,
2917         const rctf *clip_rect, const rctf *bucket_bounds)
2918 {
2919         LinkNode *node;
2920         int tri_index, image_index = 0;
2921         ImBuf *ibuf = NULL;
2922         Image *tpage_last = NULL, *tpage;
2923         ImBuf *tmpibuf = NULL;
2924
2925         if (ps->image_tot == 1) {
2926                 /* Simple loop, no context switching */
2927                 ibuf = ps->projImages[0].ibuf;
2928
2929                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2930                         project_paint_face_init(
2931                                 ps, thread_index, bucket_index, GET_INT_FROM_POINTER(node->link), 0,
2932                                 clip_rect, bucket_bounds, ibuf, &tmpibuf);
2933                 }
2934         }
2935         else {
2936
2937                 /* More complicated loop, switch between images */
2938                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2939                         tri_index = GET_INT