Cleanup: remove moar ugly G.main usages...
[blender.git] / source / blender / editors / sculpt_paint / paint_image_proj.c
1 /*
2  * ***** BEGIN GPL LICENSE BLOCK *****
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * along with this program; if not, write to the Free Software Foundation,
15  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
16  *
17  * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
18  * All rights reserved.
19  *
20  * The Original Code is: some of this file.
21  *
22  * Contributor(s): Jens Ole Wund (bjornmose), Campbell Barton (ideasman42)
23  *
24  * ***** END GPL LICENSE BLOCK *****
25  */
26
27 /** \file blender/editors/sculpt_paint/paint_image_proj.c
28  *  \ingroup edsculpt
29  *  \brief Functions to paint images in 2D and 3D.
30  */
31
32 #include <float.h>
33 #include <string.h>
34 #include <stdio.h>
35 #include <math.h>
36
37 #include "MEM_guardedalloc.h"
38
39 #ifdef WIN32
40 #  include "BLI_winstuff.h"
41 #endif
42
43 #include "BLI_blenlib.h"
44 #include "BLI_linklist.h"
45 #include "BLI_math.h"
46 #include "BLI_math_bits.h"
47 #include "BLI_math_color_blend.h"
48 #include "BLI_memarena.h"
49 #include "BLI_threads.h"
50 #include "BLI_utildefines.h"
51
52 #include "BLT_translation.h"
53
54
55 #include "IMB_imbuf.h"
56 #include "IMB_imbuf_types.h"
57
58 #include "DNA_brush_types.h"
59 #include "DNA_material_types.h"
60 #include "DNA_mesh_types.h"
61 #include "DNA_node_types.h"
62 #include "DNA_object_types.h"
63
64 #include "BKE_camera.h"
65 #include "BKE_colorband.h"
66 #include "BKE_context.h"
67 #include "BKE_colortools.h"
68 #include "BKE_depsgraph.h"
69 #include "BKE_DerivedMesh.h"
70 #include "BKE_idprop.h"
71 #include "BKE_brush.h"
72 #include "BKE_image.h"
73 #include "BKE_library.h"
74 #include "BKE_main.h"
75 #include "BKE_material.h"
76 #include "BKE_mesh.h"
77 #include "BKE_mesh_mapping.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 "UI_interface.h"
85
86 #include "ED_object.h"
87 #include "ED_mesh.h"
88 #include "ED_node.h"
89 #include "ED_paint.h"
90 #include "ED_screen.h"
91 #include "ED_uvedit.h"
92 #include "ED_view3d.h"
93
94 #include "GPU_extensions.h"
95
96 #include "WM_api.h"
97 #include "WM_types.h"
98
99 #include "RNA_access.h"
100 #include "RNA_define.h"
101 #include "RNA_enum_types.h"
102
103 #include "GPU_draw.h"
104
105 #include "IMB_colormanagement.h"
106
107 #include "bmesh.h"
108 //#include "bmesh_tools.h"
109
110 #include "paint_intern.h"
111
112 static void partial_redraw_array_init(ImagePaintPartialRedraw *pr);
113
114 /* Defines and Structs */
115 /* unit_float_to_uchar_clamp as inline function */
116 BLI_INLINE unsigned char f_to_char(const float val)
117 {
118         return unit_float_to_uchar_clamp(val);
119 }
120
121 /* ProjectionPaint defines */
122
123 /* approx the number of buckets to have under the brush,
124  * used with the brush size to set the ps->buckets_x and ps->buckets_y value.
125  *
126  * When 3 - a brush should have ~9 buckets under it at once
127  * ...this helps for threading while painting as well as
128  * avoiding initializing pixels that wont touch the brush */
129 #define PROJ_BUCKET_BRUSH_DIV 4
130
131 #define PROJ_BUCKET_RECT_MIN 4
132 #define PROJ_BUCKET_RECT_MAX 256
133
134 #define PROJ_BOUNDBOX_DIV 8
135 #define PROJ_BOUNDBOX_SQUARED  (PROJ_BOUNDBOX_DIV * PROJ_BOUNDBOX_DIV)
136
137 //#define PROJ_DEBUG_PAINT 1
138 //#define PROJ_DEBUG_NOSEAMBLEED 1
139 //#define PROJ_DEBUG_PRINT_CLIP 1
140 #define PROJ_DEBUG_WINCLIP 1
141
142
143 #ifndef PROJ_DEBUG_NOSEAMBLEED
144 /* projectFaceSeamFlags options */
145 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
146 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
147 #define PROJ_FACE_SEAM1 (1 << 0)  /* If this face has a seam on any of its edges */
148 #define PROJ_FACE_SEAM2 (1 << 1)
149 #define PROJ_FACE_SEAM3 (1 << 2)
150
151 #define PROJ_FACE_NOSEAM1   (1 << 4)
152 #define PROJ_FACE_NOSEAM2   (1 << 5)
153 #define PROJ_FACE_NOSEAM3   (1 << 6)
154
155 /* face winding */
156 #define PROJ_FACE_WINDING_INIT 1
157 #define PROJ_FACE_WINDING_CW 2
158
159 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
160  * as this number approaches  1.0f the likelihood increases of float precision errors where
161  * it is occluded by an adjacent face */
162 #define PROJ_FACE_SCALE_SEAM    0.99f
163 #endif  /* PROJ_DEBUG_NOSEAMBLEED */
164
165
166 #define PROJ_SRC_VIEW       1
167 #define PROJ_SRC_IMAGE_CAM  2
168 #define PROJ_SRC_IMAGE_VIEW 3
169 #define PROJ_SRC_VIEW_FILL  4
170
171 #define PROJ_VIEW_DATA_ID "view_data"
172 #define PROJ_VIEW_DATA_SIZE (4 * 4 + 4 * 4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
173
174 #define PROJ_BUCKET_NULL        0
175 #define PROJ_BUCKET_INIT        (1 << 0)
176 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
177
178 /* used for testing doubles, if a point is on a line etc */
179 #define PROJ_GEOM_TOLERANCE 0.00075f
180 #define PROJ_PIXEL_TOLERANCE 0.01f
181
182 /* vert flags */
183 #define PROJ_VERT_CULL 1
184
185 /* to avoid locking in tile initialization */
186 #define TILE_PENDING SET_INT_IN_POINTER(-1)
187
188 /* This is mainly a convenience struct used so we can keep an array of images we use -
189  * their imbufs, etc, in 1 array, When using threads this array is copied for each thread
190  * because 'partRedrawRect' and 'touch' values would not be thread safe */
191 typedef struct ProjPaintImage {
192         Image *ima;
193         ImBuf *ibuf;
194         ImagePaintPartialRedraw *partRedrawRect;
195         volatile void **undoRect; /* only used to build undo tiles during painting */
196         unsigned short **maskRect; /* the mask accumulation must happen on canvas, not on space screen bucket.
197                                     * Here we store the mask rectangle */
198         bool **valid; /* store flag to enforce validation of undo rectangle */
199         bool touch;
200 } ProjPaintImage;
201
202 /**
203  * Handle for stroke (operator customdata)
204  */
205 typedef struct ProjStrokeHandle {
206         /* Support for painting from multiple views at once,
207          * currently used to implement symmetry painting,
208          * we can assume at least the first is set while painting. */
209         struct ProjPaintState *ps_views[8];
210         int ps_views_tot;
211         int symmetry_flags;
212
213         int orig_brush_size;
214
215         bool need_redraw;
216
217         /* trick to bypass regular paint and allow clone picking */
218         bool is_clone_cursor_pick;
219
220         /* In ProjPaintState, only here for convenience */
221         Scene *scene;
222         Brush *brush;
223 } ProjStrokeHandle;
224
225 /* Main projection painting struct passed to all projection painting functions */
226 typedef struct ProjPaintState {
227         View3D *v3d;
228         RegionView3D *rv3d;
229         ARegion *ar;
230         Scene *scene;
231         int source; /* PROJ_SRC_**** */
232
233         /* the paint color. It can change depending of inverted mode or not */
234         float paint_color[3];
235         float paint_color_linear[3];
236         float dither;
237
238         Brush *brush;
239         short tool, blend, mode;
240
241         float brush_size;
242         Object *ob;
243         /* for symmetry, we need to store modified object matrix */
244         float obmat[4][4];
245         float obmat_imat[4][4];
246         /* end similarities with ImagePaintState */
247
248         Image *stencil_ima;
249         Image *canvas_ima;
250         Image *clone_ima;
251         float stencil_value;
252
253         /* projection painting only */
254         MemArena *arena_mt[BLENDER_MAX_THREADS]; /* for multithreading, the first item is sometimes used for non threaded cases too */
255         LinkNode **bucketRect;              /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
256         LinkNode **bucketFaces;             /* bucketRect aligned array linkList of faces overlapping each bucket */
257         unsigned char *bucketFlags;         /* store if the bucks have been initialized  */
258
259         char *vertFlags;                    /* store options per vert, now only store if the vert is pointing away from the view */
260         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 */
261         int buckets_y;
262
263         int pixel_sizeof;           /* result of project_paint_pixel_sizeof(), constant per stroke */
264
265         int image_tot;              /* size of projectImages array */
266
267         float (*screenCoords)[4];   /* verts projected into floating point screen space */
268         float screenMin[2];         /* 2D bounds for mesh verts on the screen's plane (screenspace) */
269         float screenMax[2];
270         float screen_width;         /* Calculated from screenMin & screenMax */
271         float screen_height;
272         int winx, winy;             /* from the carea or from the projection render */
273
274         /* options for projection painting */
275         bool  do_layer_clone;
276         bool  do_layer_stencil;
277         bool  do_layer_stencil_inv;
278         bool  do_stencil_brush;
279         bool  do_material_slots;
280
281         bool  do_occlude;               /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
282         bool  do_backfacecull;          /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
283         bool  do_mask_normal;           /* mask out pixels based on their normals */
284         bool  do_mask_cavity;           /* mask out pixels based on cavity */
285         bool  do_new_shading_nodes;     /* cache BKE_scene_use_new_shading_nodes value */
286         float normal_angle;             /* what angle to mask at */
287         float normal_angle__cos;         /* cos(normal_angle), faster to compare */
288         float normal_angle_inner;
289         float normal_angle_inner__cos;
290         float normal_angle_range;       /* difference between normal_angle and normal_angle_inner, for easy access */
291
292         bool do_face_sel;               /* quick access to (me->editflag & ME_EDIT_PAINT_FACE_SEL) */
293         bool is_ortho;
294         bool is_flip_object;            /* the object is negative scaled */
295         bool do_masking;              /* use masking during painting. Some operations such as airbrush may disable */
296         bool is_texbrush;              /* only to avoid running  */
297         bool is_maskbrush;            /* mask brush is applied before masking */
298 #ifndef PROJ_DEBUG_NOSEAMBLEED
299         float seam_bleed_px;
300 #endif
301         /* clone vars */
302         float cloneOffset[2];
303
304         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
305         float projectMatInv[4][4];  /* inverse of projectMat */
306         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
307         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
308         float clipsta, clipend;
309
310         /* reproject vars */
311         Image *reproject_image;
312         ImBuf *reproject_ibuf;
313         bool   reproject_ibuf_free_float;
314         bool   reproject_ibuf_free_uchar;
315
316         /* threads */
317         int thread_tot;
318         int bucketMin[2];
319         int bucketMax[2];
320         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
321
322         struct CurveMapping *cavity_curve;
323         BlurKernel *blurkernel;
324
325
326
327         /* -------------------------------------------------------------------- */
328         /* Vars shared between multiple views (keep last) */
329         /**
330          * This data is owned by ``ProjStrokeHandle.ps_views[0]``,
331          * all other views re-use the data.
332          */
333
334 #define PROJ_PAINT_STATE_SHARED_MEMCPY(ps_dst, ps_src) \
335         MEMCPY_STRUCT_OFS(ps_dst, ps_src, is_shared_user)
336
337 #define PROJ_PAINT_STATE_SHARED_CLEAR(ps) \
338         MEMSET_STRUCT_OFS(ps, 0, is_shared_user)
339
340         bool is_shared_user;
341
342         ProjPaintImage *projImages;
343         float *cavities;            /* cavity amount for vertices */
344
345 #ifndef PROJ_DEBUG_NOSEAMBLEED
346         char *faceSeamFlags;                /* store info about faces, if they are initialized etc*/
347         char *faceWindingFlags;             /* save the winding of the face in uv space, helps as an extra validation step for seam detection */
348         float (*faceSeamUVs)[3][2];         /* expanded UVs for faces to use as seams */
349         LinkNode **vertFaces;               /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
350 #endif
351
352         SpinLock *tile_lock;
353
354         DerivedMesh    *dm;
355         int  dm_totlooptri;
356         int  dm_totpoly;
357         int  dm_totedge;
358         int  dm_totvert;
359         bool dm_release;
360
361         const MVert    *dm_mvert;
362         const MEdge    *dm_medge;
363         const MPoly    *dm_mpoly;
364         const MLoop    *dm_mloop;
365         const MLoopTri *dm_mlooptri;
366
367         const MLoopUV  *dm_mloopuv_stencil;
368
369         /**
370          * \note These UV layers are aligned to \a dm_mpoly
371          * but each pointer references the start of the layer,
372          * so a loop indirection is needed as well.
373          */
374         const MLoopUV **dm_mloopuv;
375         const MLoopUV **dm_mloopuv_clone;    /* other UV map, use for cloning between layers */
376
377         bool use_colormanagement;
378 } ProjPaintState;
379
380 typedef union pixelPointer {
381         float *f_pt;            /* float buffer */
382         unsigned int *uint_pt; /* 2 ways to access a char buffer */
383         unsigned char *ch_pt;
384 } PixelPointer;
385
386 typedef union pixelStore {
387         unsigned char ch[4];
388         unsigned int uint;
389         float f[4];
390 } PixelStore;
391
392 typedef struct ProjPixel {
393         float projCoSS[2]; /* the floating point screen projection of this pixel */
394         float worldCoSS[3];
395
396         short x_px, y_px;
397
398         unsigned short image_index; /* if anyone wants to paint onto more than 65535 images they can bite me */
399         unsigned char bb_cell_index;
400
401         /* for various reasons we may want to mask out painting onto this pixel */
402         unsigned short mask;
403
404         /* Only used when the airbrush is disabled.
405          * Store the max mask value to avoid painting over an area with a lower opacity
406          * with an advantage that we can avoid touching the pixel at all, if the
407          * new mask value is lower then mask_accum */
408         unsigned short *mask_accum;
409
410         /* horrible hack, store tile valid flag pointer here to re-validate tiles used for anchored and drag-dot strokes */
411         bool *valid;
412
413         PixelPointer origColor;
414         PixelStore newColor;
415         PixelPointer pixel;
416 } ProjPixel;
417
418 typedef struct ProjPixelClone {
419         struct ProjPixel __pp;
420         PixelStore clonepx;
421 } ProjPixelClone;
422
423 /* undo tile pushing */
424 typedef struct {
425         SpinLock *lock;
426         bool masked;
427         unsigned short tile_width;
428         ImBuf **tmpibuf;
429         ProjPaintImage *pjima;
430 } TileInfo;
431
432
433
434 /* -------------------------------------------------------------------- */
435
436 /** \name MLoopTri accessor functions.
437  * \{ */
438
439 BLI_INLINE const MPoly *ps_tri_index_to_mpoly(const ProjPaintState *ps, int tri_index)
440 {
441         return &ps->dm_mpoly[ps->dm_mlooptri[tri_index].poly];
442 }
443
444 #define PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) \
445         ps->dm_mloop[lt->tri[0]].v, \
446         ps->dm_mloop[lt->tri[1]].v, \
447         ps->dm_mloop[lt->tri[2]].v,
448
449 #define PS_LOOPTRI_AS_UV_3(uvlayer, lt) \
450         uvlayer[lt->poly][lt->tri[0]].uv, \
451         uvlayer[lt->poly][lt->tri[1]].uv, \
452         uvlayer[lt->poly][lt->tri[2]].uv,
453
454 #define PS_LOOPTRI_ASSIGN_UV_3(uv_tri, uvlayer, lt)  { \
455         (uv_tri)[0] = uvlayer[lt->poly][lt->tri[0]].uv; \
456         (uv_tri)[1] = uvlayer[lt->poly][lt->tri[1]].uv; \
457         (uv_tri)[2] = uvlayer[lt->poly][lt->tri[2]].uv; \
458 } ((void)0)
459
460 /** \} */
461
462
463
464 /* Finish projection painting structs */
465
466 static TexPaintSlot *project_paint_face_paint_slot(const ProjPaintState *ps, int tri_index)
467 {
468         const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
469         Material *ma = ps->dm->mat[mp->mat_nr];
470         return ma ? ma->texpaintslot + ma->paint_active_slot : NULL;
471 }
472
473 static Image *project_paint_face_paint_image(const ProjPaintState *ps, int tri_index)
474 {
475         if (ps->do_stencil_brush) {
476                 return ps->stencil_ima;
477         }
478         else {
479                 const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
480                 Material *ma = ps->dm->mat[mp->mat_nr];
481                 TexPaintSlot *slot = ma ? ma->texpaintslot + ma->paint_active_slot : NULL;
482                 return slot ? slot->ima : ps->canvas_ima;
483         }
484 }
485
486 static TexPaintSlot *project_paint_face_clone_slot(const ProjPaintState *ps, int tri_index)
487 {
488         const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
489         Material *ma = ps->dm->mat[mp->mat_nr];
490         return ma ? ma->texpaintslot + ma->paint_clone_slot : NULL;
491 }
492
493 static Image *project_paint_face_clone_image(const ProjPaintState *ps, int tri_index)
494 {
495         const MPoly *mp = ps_tri_index_to_mpoly(ps, tri_index);
496         Material *ma = ps->dm->mat[mp->mat_nr];
497         TexPaintSlot *slot = ma ? ma->texpaintslot + ma->paint_clone_slot : NULL;
498         return slot ? slot->ima : ps->clone_ima;
499 }
500
501 /* fast projection bucket array lookup, use the safe version for bound checking  */
502 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
503 {
504         /* If we were not dealing with screenspace 2D coords we could simple do...
505          * ps->bucketRect[x + (y*ps->buckets_y)] */
506
507         /* please explain?
508          * projCoSS[0] - ps->screenMin[0]   : zero origin
509          * ... / ps->screen_width           : range from 0.0 to 1.0
510          * ... * ps->buckets_x              : use as a bucket index
511          *
512          * Second multiplication does similar but for vertical offset
513          */
514         return ( (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
515                (((int)(((projCoSS[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
516 }
517
518 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
519 {
520         int bucket_index = project_bucket_offset(ps, projCoSS);
521
522         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
523                 return -1;
524         }
525         else {
526                 return bucket_index;
527         }
528 }
529
530 static float VecZDepthOrtho(
531         const float pt[2],
532         const float v1[3], const float v2[3], const float v3[3],
533         float w[3])
534 {
535         barycentric_weights_v2(v1, v2, v3, pt, w);
536         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
537 }
538
539 static float VecZDepthPersp(
540         const float pt[2],
541         const float v1[4], const float v2[4], const float v3[4],
542         float w[3])
543 {
544         float wtot_inv, wtot;
545         float w_tmp[3];
546
547         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
548         /* for the depth we need the weights to match what
549          * barycentric_weights_v2 would return, in this case its easiest just to
550          * undo the 4th axis division and make it unit-sum
551          *
552          * don't call barycentric_weights_v2() because our callers expect 'w'
553          * to be weighted from the perspective */
554         w_tmp[0] = w[0] * v1[3];
555         w_tmp[1] = w[1] * v2[3];
556         w_tmp[2] = w[2] * v3[3];
557
558         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
559
560         if (wtot != 0.0f) {
561                 wtot_inv = 1.0f / wtot;
562
563                 w_tmp[0] = w_tmp[0] * wtot_inv;
564                 w_tmp[1] = w_tmp[1] * wtot_inv;
565                 w_tmp[2] = w_tmp[2] * wtot_inv;
566         }
567         else /* dummy values for zero area face */
568                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
569         /* done mimicing barycentric_weights_v2() */
570
571         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
572 }
573
574
575 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
576 static int project_paint_PickFace(
577         const ProjPaintState *ps, const float pt[2],
578         float w[3])
579 {
580         LinkNode *node;
581         float w_tmp[3];
582         int bucket_index;
583         int best_tri_index = -1;
584         float z_depth_best = FLT_MAX, z_depth;
585
586         bucket_index = project_bucket_offset_safe(ps, pt);
587         if (bucket_index == -1)
588                 return -1;
589
590
591
592         /* we could return 0 for 1 face buckets, as long as this function assumes
593          * that the point its testing is only every originated from an existing face */
594
595         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
596                 const int tri_index = GET_INT_FROM_POINTER(node->link);
597                 const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
598                 const float *vtri_ss[3] = {
599                     ps->screenCoords[ps->dm_mloop[lt->tri[0]].v],
600                     ps->screenCoords[ps->dm_mloop[lt->tri[1]].v],
601                     ps->screenCoords[ps->dm_mloop[lt->tri[2]].v],
602                 };
603
604
605                 if (isect_point_tri_v2(pt, UNPACK3(vtri_ss))) {
606                         if (ps->is_ortho) {
607                                 z_depth = VecZDepthOrtho(pt, UNPACK3(vtri_ss), w_tmp);
608                         }
609                         else {
610                                 z_depth = VecZDepthPersp(pt, UNPACK3(vtri_ss), w_tmp);
611                         }
612
613                         if (z_depth < z_depth_best) {
614                                 best_tri_index = tri_index;
615                                 z_depth_best = z_depth;
616                                 copy_v3_v3(w, w_tmp);
617                         }
618                 }
619         }
620
621         return best_tri_index; /* will be -1 or a valid face */
622 }
623
624 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
625 static void uvco_to_wrapped_pxco(const float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
626 {
627         /* use */
628         *x = fmodf(uv[0], 1.0f);
629         *y = fmodf(uv[1], 1.0f);
630
631         if (*x < 0.0f) *x += 1.0f;
632         if (*y < 0.0f) *y += 1.0f;
633
634         *x = *x * ibuf_x - 0.5f;
635         *y = *y * ibuf_y - 0.5f;
636 }
637
638 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
639 static bool project_paint_PickColor(
640         const ProjPaintState *ps, const float pt[2],
641         float *rgba_fp, unsigned char *rgba, const bool interp)
642 {
643         const MLoopTri *lt;
644         const float *lt_tri_uv[3];
645         float w[3], uv[2];
646         int tri_index;
647         Image *ima;
648         ImBuf *ibuf;
649         int xi, yi;
650
651         tri_index = project_paint_PickFace(ps, pt, w);
652
653         if (tri_index == -1)
654                 return 0;
655
656         lt = &ps->dm_mlooptri[tri_index];
657         PS_LOOPTRI_ASSIGN_UV_3(lt_tri_uv, ps->dm_mloopuv, lt);
658
659         interp_v2_v2v2v2(uv, UNPACK3(lt_tri_uv), w);
660
661         ima = project_paint_face_paint_image(ps, tri_index);
662         ibuf = BKE_image_get_first_ibuf(ima); /* we must have got the imbuf before getting here */
663         if (!ibuf) return 0;
664
665         if (interp) {
666                 float x, y;
667                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
668
669                 if (ibuf->rect_float) {
670                         if (rgba_fp) {
671                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
672                         }
673                         else {
674                                 float rgba_tmp_f[4];
675                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
676                                 premul_float_to_straight_uchar(rgba, rgba_tmp_f);
677                         }
678                 }
679                 else {
680                         if (rgba) {
681                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
682                         }
683                         else {
684                                 unsigned char rgba_tmp[4];
685                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
686                                 straight_uchar_to_premul_float(rgba_fp, rgba_tmp);
687                         }
688                 }
689         }
690         else {
691                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
692                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
693                 //if (xi < 0 || xi >= ibuf->x  ||  yi < 0 || yi >= ibuf->y) return 0;
694
695                 /* wrap */
696                 xi = mod_i((int)(uv[0] * ibuf->x), ibuf->x);
697                 yi = mod_i((int)(uv[1] * ibuf->y), ibuf->y);
698
699                 if (rgba) {
700                         if (ibuf->rect_float) {
701                                 const float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
702                                 premul_float_to_straight_uchar(rgba, rgba_tmp_fp);
703                         }
704                         else {
705                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
706                         }
707                 }
708
709                 if (rgba_fp) {
710                         if (ibuf->rect_float) {
711                                 copy_v4_v4(rgba_fp, (ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
712                         }
713                         else {
714                                 unsigned char *tmp_ch = ((unsigned char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
715                                 straight_uchar_to_premul_float(rgba_fp, tmp_ch);
716                         }
717                 }
718         }
719         BKE_image_release_ibuf(ima, ibuf, NULL);
720         return 1;
721 }
722
723 /**
724  * Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusion test)
725  * \return
726  * -  `0`:   no occlusion
727  * - `-1`: no occlusion but 2D intersection is true
728  * -  `1`: occluded
729  * -  `2`: occluded with `w[3]` weights set (need to know in some cases)
730  */
731 static int project_paint_occlude_ptv(
732         const float pt[3],
733         const float v1[4], const float v2[4], const float v3[4],
734         float w[3], const bool is_ortho)
735 {
736         /* if all are behind us, return false */
737         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
738                 return 0;
739
740         /* do a 2D point in try intersection */
741         if (!isect_point_tri_v2(pt, v1, v2, v3))
742                 return 0;  /* we know there is  */
743
744
745         /* From here on we know there IS an intersection */
746         /* if ALL of the verts are infront of us then we know it intersects ? */
747         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
748                 return 1;
749         }
750         else {
751                 /* we intersect? - find the exact depth at the point of intersection */
752                 /* Is this point is occluded by another face? */
753                 if (is_ortho) {
754                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
755                 }
756                 else {
757                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
758                 }
759         }
760         return -1;
761 }
762
763
764 static int project_paint_occlude_ptv_clip(
765         const float pt[3],
766         const float v1[4], const float v2[4], const float v3[4],
767         const float v1_3d[3], const float v2_3d[3], const float v3_3d[3],
768         float w[3], const bool is_ortho, RegionView3D *rv3d)
769 {
770         float wco[3];
771         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, is_ortho);
772
773         if (ret <= 0)
774                 return ret;
775
776         if (ret == 1) { /* weights not calculated */
777                 if (is_ortho) {
778                         barycentric_weights_v2(v1, v2, v3, pt, w);
779                 }
780                 else {
781                         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
782                 }
783         }
784
785         /* Test if we're in the clipped area, */
786         interp_v3_v3v3v3(wco, v1_3d, v2_3d, v3_3d, w);
787
788         if (!ED_view3d_clipping_test(rv3d, wco, true)) {
789                 return 1;
790         }
791
792         return -1;
793 }
794
795
796 /* Check if a screenspace location is occluded by any other faces
797  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
798  * and doesn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
799 static bool project_bucket_point_occluded(
800         const ProjPaintState *ps, LinkNode *bucketFace,
801         const int orig_face, const float pixelScreenCo[4])
802 {
803         int isect_ret;
804         const bool do_clip = ps->rv3d ? (ps->rv3d->rflag & RV3D_CLIPPING) != 0 : 0;
805
806         /* we could return 0 for 1 face buckets, as long as this function assumes
807          * that the point its testing is only every originated from an existing face */
808
809         for (; bucketFace; bucketFace = bucketFace->next) {
810                 const int tri_index = GET_INT_FROM_POINTER(bucketFace->link);
811
812                 if (orig_face != tri_index) {
813                         const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
814                         const float *vtri_ss[3] = {
815                             ps->screenCoords[ps->dm_mloop[lt->tri[0]].v],
816                             ps->screenCoords[ps->dm_mloop[lt->tri[1]].v],
817                             ps->screenCoords[ps->dm_mloop[lt->tri[2]].v],
818                         };
819                         float w[3];
820
821                         if (do_clip) {
822                                 const float *vtri_co[3] = {
823                                     ps->dm_mvert[ps->dm_mloop[lt->tri[0]].v].co,
824                                     ps->dm_mvert[ps->dm_mloop[lt->tri[1]].v].co,
825                                     ps->dm_mvert[ps->dm_mloop[lt->tri[2]].v].co,
826                                 };
827                                 isect_ret = project_paint_occlude_ptv_clip(
828                                         pixelScreenCo, UNPACK3(vtri_ss), UNPACK3(vtri_co),
829                                         w, ps->is_ortho, ps->rv3d);
830                         }
831                         else {
832                                 isect_ret = project_paint_occlude_ptv(
833                                         pixelScreenCo, UNPACK3(vtri_ss),
834                                         w, ps->is_ortho);
835                         }
836
837                         if (isect_ret >= 1) {
838                                 /* TODO - we may want to cache the first hit,
839                                  * it is not possible to swap the face order in the list anymore */
840                                 return true;
841                         }
842                 }
843         }
844         return false;
845 }
846
847 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
848  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
849 #define ISECT_TRUE 1
850 #define ISECT_TRUE_P1 2
851 #define ISECT_TRUE_P2 3
852 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
853 {
854         float y_diff;
855
856         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
857                 *x_isect = p1[0];
858                 return ISECT_TRUE_P1;
859         }
860         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
861                 *x_isect = p2[0];
862                 return ISECT_TRUE_P2;
863         }
864
865         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
866
867         if (y_diff < 0.000001f) {
868                 *x_isect = (p1[0] + p2[0]) * 0.5f;
869                 return ISECT_TRUE;
870         }
871
872         if (p1[1] > y_level && p2[1] < y_level) {
873                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /* (p1[1] - p2[1]); */
874                 return ISECT_TRUE;
875         }
876         else if (p1[1] < y_level && p2[1] > y_level) {
877                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /* (p2[1] - p1[1]); */
878                 return ISECT_TRUE;
879         }
880         else {
881                 return 0;
882         }
883 }
884
885 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
886 {
887         float x_diff;
888
889         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
890                 *y_isect = p1[1];
891                 return ISECT_TRUE_P1;
892         }
893         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
894                 *y_isect = p2[1];
895                 return ISECT_TRUE_P2;
896         }
897
898         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
899
900         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
901                 *y_isect = (p1[0] + p2[0]) * 0.5f;
902                 return ISECT_TRUE;
903         }
904
905         if (p1[0] > x_level && p2[0] < x_level) {
906                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff;  /* (p1[0] - p2[0]); */
907                 return ISECT_TRUE;
908         }
909         else if (p1[0] < x_level && p2[0] > x_level) {
910                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff;  /* (p2[0] - p1[0]); */
911                 return ISECT_TRUE;
912         }
913         else {
914                 return 0;
915         }
916 }
917
918 /* simple func use for comparing UV locations to check if there are seams.
919  * Its possible this gives incorrect results, when the UVs for 1 face go into the next
920  * tile, but do not do this for the adjacent face, it could return a false positive.
921  * This is so unlikely that Id not worry about it. */
922 #ifndef PROJ_DEBUG_NOSEAMBLEED
923 static bool cmp_uv(const float vec2a[2], const float vec2b[2])
924 {
925         /* if the UV's are not between 0.0 and 1.0 */
926         float xa = fmodf(vec2a[0], 1.0f);
927         float ya = fmodf(vec2a[1], 1.0f);
928
929         float xb = fmodf(vec2b[0], 1.0f);
930         float yb = fmodf(vec2b[1], 1.0f);
931
932         if (xa < 0.0f) xa += 1.0f;
933         if (ya < 0.0f) ya += 1.0f;
934
935         if (xb < 0.0f) xb += 1.0f;
936         if (yb < 0.0f) yb += 1.0f;
937
938         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
939 }
940 #endif
941
942 /* set min_px and max_px to the image space bounds of the UV coords
943  * return zero if there is no area in the returned rectangle */
944 #ifndef PROJ_DEBUG_NOSEAMBLEED
945 static bool pixel_bounds_uv(
946         const float uv_quad[4][2],
947         rcti *bounds_px,
948         const int ibuf_x, const int ibuf_y
949         )
950 {
951         float min_uv[2], max_uv[2]; /* UV bounds */
952
953         INIT_MINMAX2(min_uv, max_uv);
954
955         minmax_v2v2_v2(min_uv, max_uv, uv_quad[0]);
956         minmax_v2v2_v2(min_uv, max_uv, uv_quad[1]);
957         minmax_v2v2_v2(min_uv, max_uv, uv_quad[2]);
958         minmax_v2v2_v2(min_uv, max_uv, uv_quad[3]);
959
960         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
961         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
962
963         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
964         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
965
966         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
967
968         /* face uses no UV area when quantized to pixels? */
969         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
970 }
971 #endif
972
973 static bool pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
974 {
975         float min_uv[2], max_uv[2]; /* UV bounds */
976
977         if (tot == 0) {
978                 return 0;
979         }
980
981         INIT_MINMAX2(min_uv, max_uv);
982
983         while (tot--) {
984                 minmax_v2v2_v2(min_uv, max_uv, (*uv));
985                 uv++;
986         }
987
988         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
989         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
990
991         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
992         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
993
994         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
995
996         /* face uses no UV area when quantized to pixels? */
997         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
998 }
999
1000 #ifndef PROJ_DEBUG_NOSEAMBLEED
1001
1002 static void project_face_winding_init(const ProjPaintState *ps, const int tri_index)
1003 {
1004         /* detect the winding of faces in uv space */
1005         const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
1006         const float *lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv, lt) };
1007         float winding = cross_tri_v2(lt_tri_uv[0], lt_tri_uv[1], lt_tri_uv[2]);
1008
1009         if (winding > 0)
1010                 ps->faceWindingFlags[tri_index] |= PROJ_FACE_WINDING_CW;
1011
1012         ps->faceWindingFlags[tri_index] |= PROJ_FACE_WINDING_INIT;
1013 }
1014
1015 /* This function returns 1 if this face has a seam along the 2 face-vert indices
1016  * 'orig_i1_fidx' and 'orig_i2_fidx' */
1017 static bool check_seam(
1018         const ProjPaintState *ps,
1019         const int orig_face, const int orig_i1_fidx, const int orig_i2_fidx,
1020         int *other_face, int *orig_fidx)
1021 {
1022         const MLoopTri *orig_lt = &ps->dm_mlooptri[orig_face];
1023         const float *orig_lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv, orig_lt) };
1024         /* vert indices from face vert order indices */
1025         const unsigned int i1 = ps->dm_mloop[orig_lt->tri[orig_i1_fidx]].v;
1026         const unsigned int i2 = ps->dm_mloop[orig_lt->tri[orig_i2_fidx]].v;
1027         LinkNode *node;
1028         int i1_fidx = -1, i2_fidx = -1; /* index in face */
1029
1030         for (node = ps->vertFaces[i1]; node; node = node->next) {
1031                 const int tri_index = GET_INT_FROM_POINTER(node->link);
1032
1033                 if (tri_index != orig_face) {
1034                         const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
1035                         const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
1036                         /* could check if the 2 faces images match here,
1037                          * but then there wouldn't be a way to return the opposite face's info */
1038
1039
1040                         /* We need to know the order of the verts in the adjacent face
1041                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
1042                         i1_fidx = BKE_MESH_TESSTRI_VINDEX_ORDER(lt_vtri, i1);
1043                         i2_fidx = BKE_MESH_TESSTRI_VINDEX_ORDER(lt_vtri, i2);
1044
1045                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
1046                         if (i2_fidx != -1) {
1047                                 const float *lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv, lt) };
1048                                 Image *tpage = project_paint_face_paint_image(ps, tri_index);
1049                                 Image *orig_tpage = project_paint_face_paint_image(ps, orig_face);
1050
1051                                 BLI_assert(i1_fidx != -1);
1052
1053                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
1054
1055                                 /* set up the other face */
1056                                 *other_face = tri_index;
1057
1058                                 /* we check if difference is 1 here, else we might have a case of edge 2-0 for a tri */
1059                                 *orig_fidx = (i1_fidx < i2_fidx && (i2_fidx - i1_fidx == 1)) ? i1_fidx : i2_fidx;
1060
1061                                 /* initialize face winding if needed */
1062                                 if ((ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_INIT) == 0)
1063                                         project_face_winding_init(ps, tri_index);
1064
1065                                 /* first test if they have the same image */
1066                                 if ((orig_tpage == tpage) &&
1067                                     cmp_uv(orig_lt_tri_uv[orig_i1_fidx], lt_tri_uv[i1_fidx]) &&
1068                                     cmp_uv(orig_lt_tri_uv[orig_i2_fidx], lt_tri_uv[i2_fidx]))
1069                                 {
1070                                         /* if faces don't have the same winding in uv space,
1071                                          * they are on the same side so edge is boundary */
1072                                         if ((ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_CW) !=
1073                                             (ps->faceWindingFlags[orig_face] & PROJ_FACE_WINDING_CW))
1074                                         {
1075                                                 return 1;
1076                                         }
1077
1078                                         // printf("SEAM (NONE)\n");
1079                                         return 0;
1080
1081                                 }
1082                                 else {
1083                                         // printf("SEAM (UV GAP)\n");
1084                                         return 1;
1085                                 }
1086                         }
1087                 }
1088         }
1089         // printf("SEAM (NO FACE)\n");
1090         *other_face = -1;
1091         return 1;
1092 }
1093
1094 #define SMALL_NUMBER  1.e-6f
1095 BLI_INLINE float shell_v2v2_normal_dir_to_dist(float n[2], float d[2])
1096 {
1097         const float angle_cos = (normalize_v2(n) < SMALL_NUMBER) ? fabsf(dot_v2v2(d, n)) : 0.0f;
1098         return (UNLIKELY(angle_cos < SMALL_NUMBER)) ? 1.0f : (1.0f / angle_cos);
1099 }
1100 #undef SMALL_NUMBER
1101
1102 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
1103  * since the outset coords are a margin that keep an even distance from the original UV's,
1104  * note that the image aspect is taken into account */
1105 static void uv_image_outset(
1106         float (*orig_uv)[2], float (*outset_uv)[2], const float scaler,
1107         const int ibuf_x, const int ibuf_y, const bool cw)
1108 {
1109         /* disallow shell-thickness to outset extreme values,
1110          * otherwise near zero area UV's may extend thousands of pixels. */
1111         const float scale_clamp = 5.0f;
1112
1113         float a1, a2, a3;
1114         float puv[3][2]; /* pixelspace uv's */
1115         float no1[2], no2[2], no3[2]; /* normals */
1116         float dir1[2], dir2[2], dir3[2];
1117         float ibuf_inv[2];
1118
1119         ibuf_inv[0] = 1.0f / (float)ibuf_x;
1120         ibuf_inv[1] = 1.0f / (float)ibuf_y;
1121
1122         /* make UV's in pixel space so we can */
1123         puv[0][0] = orig_uv[0][0] * ibuf_x;
1124         puv[0][1] = orig_uv[0][1] * ibuf_y;
1125
1126         puv[1][0] = orig_uv[1][0] * ibuf_x;
1127         puv[1][1] = orig_uv[1][1] * ibuf_y;
1128
1129         puv[2][0] = orig_uv[2][0] * ibuf_x;
1130         puv[2][1] = orig_uv[2][1] * ibuf_y;
1131
1132         /* face edge directions */
1133         sub_v2_v2v2(dir1, puv[1], puv[0]);
1134         sub_v2_v2v2(dir2, puv[2], puv[1]);
1135         sub_v2_v2v2(dir3, puv[0], puv[2]);
1136         normalize_v2(dir1);
1137         normalize_v2(dir2);
1138         normalize_v2(dir3);
1139
1140         /* here we just use the orthonormality property (a1, a2) dot (a2, -a1) = 0
1141          * to get normals from the edge directions based on the winding */
1142         if (cw) {
1143                 no1[0] = -dir3[1] - dir1[1];
1144                 no1[1] =  dir3[0] + dir1[0];
1145                 no2[0] = -dir1[1] - dir2[1];
1146                 no2[1] =  dir1[0] + dir2[0];
1147                 no3[0] = -dir2[1] - dir3[1];
1148                 no3[1] =  dir2[0] + dir3[0];
1149         }
1150         else {
1151                 no1[0] =  dir3[1] + dir1[1];
1152                 no1[1] = -dir3[0] - dir1[0];
1153                 no2[0] =  dir1[1] + dir2[1];
1154                 no2[1] = -dir1[0] - dir2[0];
1155                 no3[0] =  dir2[1] + dir3[1];
1156                 no3[1] = -dir2[0] - dir3[0];
1157         }
1158
1159         a1 = shell_v2v2_normal_dir_to_dist(no1, dir3);
1160         a2 = shell_v2v2_normal_dir_to_dist(no2, dir1);
1161         a3 = shell_v2v2_normal_dir_to_dist(no3, dir2);
1162
1163         CLAMP_MAX(a1, scale_clamp);
1164         CLAMP_MAX(a2, scale_clamp);
1165         CLAMP_MAX(a3, scale_clamp);
1166
1167         mul_v2_fl(no1, a1 * scaler);
1168         mul_v2_fl(no2, a2 * scaler);
1169         mul_v2_fl(no3, a3 * scaler);
1170         add_v2_v2v2(outset_uv[0], puv[0], no1);
1171         add_v2_v2v2(outset_uv[1], puv[1], no2);
1172         add_v2_v2v2(outset_uv[2], puv[2], no3);
1173
1174         mul_v2_v2(outset_uv[0], ibuf_inv);
1175         mul_v2_v2(outset_uv[1], ibuf_inv);
1176         mul_v2_v2(outset_uv[2], ibuf_inv);
1177 }
1178
1179 /*
1180  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1181  * 1<<i - where i is (0-3)
1182  *
1183  * If we're multithreadng, make sure threads are locked when this is called
1184  */
1185 static void project_face_seams_init(const ProjPaintState *ps, const int tri_index)
1186 {
1187         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1188         int fidx1 = 2;
1189         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 */
1190
1191         /* initialize face winding if needed */
1192         if ((ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_INIT) == 0)
1193                 project_face_winding_init(ps, tri_index);
1194
1195         do {
1196                 if ((ps->faceSeamFlags[tri_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1197                         if (check_seam(ps, tri_index, fidx1, fidx2, &other_face, &other_fidx)) {
1198                                 ps->faceSeamFlags[tri_index] |= 1 << fidx1;
1199                                 if (other_face != -1)
1200                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1201                         }
1202                         else {
1203                                 ps->faceSeamFlags[tri_index] |= 16 << fidx1;
1204                                 if (other_face != -1)
1205                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1206                         }
1207                 }
1208
1209                 fidx2 = fidx1;
1210         } while (fidx1--);
1211 }
1212 #endif // PROJ_DEBUG_NOSEAMBLEED
1213
1214
1215 /* Converts a UV location to a 3D screenspace location
1216  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1217  *
1218  * This is used for finding a pixels location in screenspace for painting */
1219 static void screen_px_from_ortho(
1220         const float uv[2],
1221         const float v1co[3], const float v2co[3], const float v3co[3],  /* Screenspace coords */
1222         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1223         float pixelScreenCo[4],
1224         float w[3])
1225 {
1226         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1227         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1228 }
1229
1230 /* same as screen_px_from_ortho except we
1231  * do perspective correction on the pixel coordinate */
1232 static void screen_px_from_persp(
1233         const float uv[2],
1234         const float v1co[4], const float v2co[4], const float v3co[4],  /* screenspace coords */
1235         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1236         float pixelScreenCo[4],
1237         float w[3])
1238 {
1239         float w_int[3];
1240         float wtot_inv, wtot;
1241         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1242
1243         /* re-weight from the 4th coord of each screen vert */
1244         w_int[0] = w[0] * v1co[3];
1245         w_int[1] = w[1] * v2co[3];
1246         w_int[2] = w[2] * v3co[3];
1247
1248         wtot = w_int[0] + w_int[1] + w_int[2];
1249
1250         if (wtot > 0.0f) {
1251                 wtot_inv = 1.0f / wtot;
1252                 w_int[0] *= wtot_inv;
1253                 w_int[1] *= wtot_inv;
1254                 w_int[2] *= wtot_inv;
1255         }
1256         else {
1257                 w[0] = w[1] = w[2] =
1258                 w_int[0] = w_int[1] = w_int[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1259         }
1260         /* done re-weighting */
1261
1262         /* do interpolation based on projected weight */
1263         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w_int);
1264 }
1265
1266
1267 /**
1268  * Set a direction vector based on a screen location.
1269  * (use for perspective view, else we can simply use `ps->viewDir`)
1270  *
1271  * Similar functionality to #ED_view3d_win_to_vector
1272  *
1273  * \param r_dir: Resulting direction (length is undefined).
1274  */
1275 static void screen_px_to_vector_persp(
1276         int winx, int winy, const float projmat_inv[4][4], const float view_pos[3],
1277         const float co_px[2],
1278         float r_dir[3])
1279 {
1280         r_dir[0] = 2.0f * (co_px[0] / winx) - 1.0f;
1281         r_dir[1] = 2.0f * (co_px[1] / winy) - 1.0f;
1282         r_dir[2] = -0.5f;
1283         mul_project_m4_v3((float(*)[4])projmat_inv, r_dir);
1284         sub_v3_v3(r_dir, view_pos);
1285 }
1286
1287 /**
1288  * Special function to return the factor to a point along a line in pixel space.
1289  *
1290  * This is needed since we can't use #line_point_factor_v2 for perspective screen-space coords.
1291  *
1292  * \param p: 2D screen-space location.
1293  * \param v1, v2: 3D object-space locations.
1294  */
1295 static float screen_px_line_point_factor_v2_persp(
1296         const ProjPaintState *ps,
1297         const float p[2],
1298         const float v1[3], const float v2[3])
1299 {
1300         const float zero[3] = {0};
1301         float v1_proj[3], v2_proj[3];
1302         float dir[3];
1303
1304         screen_px_to_vector_persp(ps->winx, ps->winy, ps->projectMatInv, ps->viewPos, p, dir);
1305
1306         sub_v3_v3v3(v1_proj, v1, ps->viewPos);
1307         sub_v3_v3v3(v2_proj, v2, ps->viewPos);
1308
1309         project_plane_v3_v3v3(v1_proj, v1_proj, dir);
1310         project_plane_v3_v3v3(v2_proj, v2_proj, dir);
1311
1312         return line_point_factor_v2(zero, v1_proj, v2_proj);
1313 }
1314
1315
1316 static void project_face_pixel(
1317         const float *lt_tri_uv[3], ImBuf *ibuf_other, const float w[3],
1318         unsigned char rgba_ub[4], float rgba_f[4])
1319 {
1320         float uv_other[2], x, y;
1321
1322         interp_v2_v2v2v2(uv_other, UNPACK3(lt_tri_uv), w);
1323
1324         /* use */
1325         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1326
1327         if (ibuf_other->rect_float) { /* from float to float */
1328                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1329         }
1330         else { /* from char to float */
1331                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1332         }
1333
1334 }
1335
1336 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1337 static float project_paint_uvpixel_mask(
1338         const ProjPaintState *ps,
1339         const int tri_index,
1340         const float w[3])
1341 {
1342         float mask;
1343
1344         /* Image Mask */
1345         if (ps->do_layer_stencil) {
1346                 /* another UV maps image is masking this one's */
1347                 ImBuf *ibuf_other;
1348                 Image *other_tpage = ps->stencil_ima;
1349
1350                 if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1351                         const MLoopTri *lt_other = &ps->dm_mlooptri[tri_index];
1352                         const float *lt_other_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv, lt_other) };
1353
1354                         /* BKE_image_acquire_ibuf - TODO - this may be slow */
1355                         unsigned char rgba_ub[4];
1356                         float rgba_f[4];
1357
1358                         project_face_pixel(lt_other_tri_uv, ibuf_other, w, rgba_ub, rgba_f);
1359
1360                         if (ibuf_other->rect_float) { /* from float to float */
1361                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) * (1.0f / 3.0f)) * rgba_f[3];
1362                         }
1363                         else { /* from char to float */
1364                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) * (1.0f / (255.0f * 3.0f))) * (rgba_ub[3] * (1.0f / 255.0f));
1365                         }
1366
1367                         BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1368
1369                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1370                                 mask = (1.0f - mask);
1371
1372                         if (mask == 0.0f) {
1373                                 return 0.0f;
1374                         }
1375                 }
1376                 else {
1377                         return 0.0f;
1378                 }
1379         }
1380         else {
1381                 mask = 1.0f;
1382         }
1383
1384         if (ps->do_mask_cavity) {
1385                 const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
1386                 const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
1387                 float ca1, ca2, ca3, ca_mask;
1388                 ca1 = ps->cavities[lt_vtri[0]];
1389                 ca2 = ps->cavities[lt_vtri[1]];
1390                 ca3 = ps->cavities[lt_vtri[2]];
1391
1392                 ca_mask = w[0] * ca1 + w[1] * ca2 + w[2] * ca3;
1393                 ca_mask = curvemapping_evaluateF(ps->cavity_curve, 0, ca_mask);
1394                 CLAMP(ca_mask, 0.0f, 1.0f);
1395                 mask *= ca_mask;
1396         }
1397
1398         /* calculate mask */
1399         if (ps->do_mask_normal) {
1400                 const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
1401                 const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
1402                 const MPoly *mp = &ps->dm_mpoly[lt->poly];
1403                 float no[3], angle_cos;
1404
1405                 if (mp->flag & ME_SMOOTH) {
1406                         const short *no1, *no2, *no3;
1407                         no1 = ps->dm_mvert[lt_vtri[0]].no;
1408                         no2 = ps->dm_mvert[lt_vtri[1]].no;
1409                         no3 = ps->dm_mvert[lt_vtri[2]].no;
1410
1411                         no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1412                         no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1413                         no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1414                         normalize_v3(no);
1415                 }
1416                 else {
1417                         /* incase the */
1418 #if 1
1419                         /* normalizing per pixel isn't optimal, we could cache or check ps->*/
1420                         normal_tri_v3(no,
1421                                       ps->dm_mvert[lt_vtri[0]].co,
1422                                       ps->dm_mvert[lt_vtri[1]].co,
1423                                       ps->dm_mvert[lt_vtri[2]].co);
1424 #else
1425                         /* don't use because some modifiers dont have normal data (subsurf for eg) */
1426                         copy_v3_v3(no, (float *)ps->dm->getTessFaceData(ps->dm, tri_index, CD_NORMAL));
1427 #endif
1428                 }
1429
1430                 if (UNLIKELY(ps->is_flip_object)) {
1431                         negate_v3(no);
1432                 }
1433
1434                 /* now we can use the normal as a mask */
1435                 if (ps->is_ortho) {
1436                         angle_cos = dot_v3v3(ps->viewDir, no);
1437                 }
1438                 else {
1439                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1440                         float viewDirPersp[3];
1441                         const float *co1, *co2, *co3;
1442                         co1 = ps->dm_mvert[lt_vtri[0]].co;
1443                         co2 = ps->dm_mvert[lt_vtri[1]].co;
1444                         co3 = ps->dm_mvert[lt_vtri[2]].co;
1445
1446                         /* Get the direction from the viewPoint to the pixel and normalize */
1447                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1448                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1449                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1450                         normalize_v3(viewDirPersp);
1451                         if (UNLIKELY(ps->is_flip_object)) {
1452                                 negate_v3(viewDirPersp);
1453                         }
1454
1455                         angle_cos = dot_v3v3(viewDirPersp, no);
1456                 }
1457
1458                 if (angle_cos <= ps->normal_angle__cos) {
1459                         return 0.0f; /* outsize the normal limit*/
1460                 }
1461                 else if (angle_cos < ps->normal_angle_inner__cos) {
1462                         mask *= (ps->normal_angle - acosf(angle_cos)) / ps->normal_angle_range;
1463                 } /* otherwise no mask normal is needed, were within the limit */
1464         }
1465
1466         /* This only works when the opacity dosnt change while painting, stylus pressure messes with this
1467          * so don't use it. */
1468         // if (ps->is_airbrush == 0) mask *= BKE_brush_alpha_get(ps->brush);
1469
1470         return mask;
1471 }
1472
1473 static int project_paint_pixel_sizeof(const short tool)
1474 {
1475         if ((tool == PAINT_TOOL_CLONE) || (tool == PAINT_TOOL_SMEAR)) {
1476                 return sizeof(ProjPixelClone);
1477         }
1478         else {
1479                 return sizeof(ProjPixel);
1480         }
1481 }
1482
1483 static int project_paint_undo_subtiles(const TileInfo *tinf, int tx, int ty)
1484 {
1485         ProjPaintImage *pjIma = tinf->pjima;
1486         int tile_index = tx + ty * tinf->tile_width;
1487         bool generate_tile = false;
1488
1489         /* double check lock to avoid locking */
1490         if (UNLIKELY(!pjIma->undoRect[tile_index])) {
1491                 if (tinf->lock)
1492                         BLI_spin_lock(tinf->lock);
1493                 if (LIKELY(!pjIma->undoRect[tile_index])) {
1494                         pjIma->undoRect[tile_index] = TILE_PENDING;
1495                         generate_tile = true;
1496                 }
1497                 if (tinf->lock)
1498                         BLI_spin_unlock(tinf->lock);
1499         }
1500
1501
1502         if (generate_tile) {
1503                 ListBase *undo_tiles = ED_image_undo_get_tiles();
1504                 volatile void *undorect;
1505                 if (tinf->masked) {
1506                         undorect = image_undo_push_tile(
1507                                 undo_tiles, pjIma->ima, pjIma->ibuf, tinf->tmpibuf,
1508                                 tx, ty, &pjIma->maskRect[tile_index], &pjIma->valid[tile_index], true, false);
1509                 }
1510                 else {
1511                         undorect = image_undo_push_tile(
1512                                 undo_tiles, pjIma->ima, pjIma->ibuf, tinf->tmpibuf,
1513                                 tx, ty, NULL, &pjIma->valid[tile_index], true, false);
1514                 }
1515
1516                 pjIma->ibuf->userflags |= IB_BITMAPDIRTY;
1517                 /* tile ready, publish */
1518                 if (tinf->lock)
1519                         BLI_spin_lock(tinf->lock);
1520                 pjIma->undoRect[tile_index] = undorect;
1521                 if (tinf->lock)
1522                         BLI_spin_unlock(tinf->lock);
1523
1524         }
1525
1526         return tile_index;
1527 }
1528
1529 /* run this function when we know a bucket's, face's pixel can be initialized,
1530  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1531 static ProjPixel *project_paint_uvpixel_init(
1532         const ProjPaintState *ps,
1533         MemArena *arena,
1534         const TileInfo *tinf,
1535         int x_px, int y_px,
1536         const float mask,
1537         const int tri_index,
1538         const float pixelScreenCo[4],
1539         const float world_spaceCo[3],
1540         const float w[3])
1541 {
1542         ProjPixel *projPixel;
1543         int x_tile, y_tile;
1544         int x_round, y_round;
1545         int tile_offset;
1546         /* volatile is important here to ensure pending check is not optimized away by compiler*/
1547         volatile int tile_index;
1548
1549         ProjPaintImage *projima = tinf->pjima;
1550         ImBuf *ibuf = projima->ibuf;
1551         /* wrap pixel location */
1552
1553         x_px = mod_i(x_px, ibuf->x);
1554         y_px = mod_i(y_px, ibuf->y);
1555
1556         BLI_assert(ps->pixel_sizeof == project_paint_pixel_sizeof(ps->tool));
1557         projPixel = BLI_memarena_alloc(arena, ps->pixel_sizeof);
1558
1559         /* calculate the undo tile offset of the pixel, used to store the original
1560          * pixel color and accumulated mask if any */
1561         x_tile =  x_px >> IMAPAINT_TILE_BITS;
1562         y_tile =  y_px >> IMAPAINT_TILE_BITS;
1563
1564         x_round = x_tile * IMAPAINT_TILE_SIZE;
1565         y_round = y_tile * IMAPAINT_TILE_SIZE;
1566         //memset(projPixel, 0, size);
1567
1568         tile_offset = (x_px - x_round) + (y_px - y_round) * IMAPAINT_TILE_SIZE;
1569         tile_index = project_paint_undo_subtiles(tinf, x_tile, y_tile);
1570
1571         /* other thread may be initializing the tile so wait here */
1572         while (projima->undoRect[tile_index] == TILE_PENDING)
1573                 ;
1574
1575         BLI_assert(tile_index < (IMAPAINT_TILE_NUMBER(ibuf->x) * IMAPAINT_TILE_NUMBER(ibuf->y)));
1576         BLI_assert(tile_offset < (IMAPAINT_TILE_SIZE * IMAPAINT_TILE_SIZE));
1577
1578         projPixel->valid = projima->valid[tile_index];
1579
1580         if (ibuf->rect_float) {
1581                 projPixel->pixel.f_pt = ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1582                 projPixel->origColor.f_pt = (float *)projima->undoRect[tile_index] + 4 * tile_offset;
1583                 zero_v4(projPixel->newColor.f);
1584         }
1585         else {
1586                 projPixel->pixel.ch_pt = (unsigned char *)(ibuf->rect + (x_px + y_px * ibuf->x));
1587                 projPixel->origColor.uint_pt = (unsigned int *)projima->undoRect[tile_index] + tile_offset;
1588                 projPixel->newColor.uint = 0;
1589         }
1590
1591         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1592         if (ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D) {
1593                 copy_v3_v3(projPixel->worldCoSS, world_spaceCo);
1594         }
1595
1596         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1597
1598         projPixel->x_px = x_px;
1599         projPixel->y_px = y_px;
1600
1601         projPixel->mask = (unsigned short)(mask * 65535);
1602         if (ps->do_masking)
1603                 projPixel->mask_accum = projima->maskRect[tile_index] + tile_offset;
1604         else
1605                 projPixel->mask_accum = NULL;
1606
1607         /* which bounding box cell are we in?, needed for undo */
1608         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1609                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1610
1611         /* done with view3d_project_float inline */
1612         if (ps->tool == PAINT_TOOL_CLONE) {
1613                 if (ps->dm_mloopuv_clone) {
1614                         ImBuf *ibuf_other;
1615                         Image *other_tpage = project_paint_face_clone_image(ps, tri_index);
1616
1617                         if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1618                                 const MLoopTri *lt_other = &ps->dm_mlooptri[tri_index];
1619                                 const float *lt_other_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv_clone, lt_other) };
1620
1621                                 /* BKE_image_acquire_ibuf - TODO - this may be slow */
1622
1623                                 if (ibuf->rect_float) {
1624                                         if (ibuf_other->rect_float) { /* from float to float */
1625                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1626                                         }
1627                                         else { /* from char to float */
1628                                                 unsigned char rgba_ub[4];
1629                                                 float rgba[4];
1630                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, rgba_ub, NULL);
1631                                                 if (ps->use_colormanagement) {
1632                                                         srgb_to_linearrgb_uchar4(rgba, rgba_ub);
1633                                                 }
1634                                                 else {
1635                                                         rgba_uchar_to_float(rgba, rgba_ub);
1636                                                 }
1637                                                 straight_to_premul_v4_v4(((ProjPixelClone *)projPixel)->clonepx.f, rgba);
1638                                         }
1639                                 }
1640                                 else {
1641                                         if (ibuf_other->rect_float) { /* float to char */
1642                                                 float rgba[4];
1643                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, NULL, rgba);
1644                                                 premul_to_straight_v4(rgba);
1645                                                 if (ps->use_colormanagement) {
1646                                                         linearrgb_to_srgb_uchar3(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1647                                                 }
1648                                                 else {
1649                                                         rgb_float_to_uchar(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1650                                                 }
1651                                                 ((ProjPixelClone *)projPixel)->clonepx.ch[3] =  rgba[3] * 255;
1652                                         }
1653                                         else { /* char to char */
1654                                                 project_face_pixel(lt_other_tri_uv, ibuf_other, w, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1655                                         }
1656                                 }
1657
1658                                 BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1659                         }
1660                         else {
1661                                 if (ibuf->rect_float) {
1662                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1663                                 }
1664                                 else {
1665                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1666                                 }
1667                         }
1668
1669                 }
1670                 else {
1671                         float co[2];
1672                         sub_v2_v2v2(co, projPixel->projCoSS, ps->cloneOffset);
1673
1674                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1675                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1676                         if (ibuf->rect_float) {
1677                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1678                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1679                                 }
1680                         }
1681                         else {
1682                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1683                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1684                                 }
1685                         }
1686                 }
1687         }
1688
1689 #ifdef PROJ_DEBUG_PAINT
1690         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1691         else                  projPixel->pixel.ch_pt[0] = 0;
1692 #endif
1693         /* pointer arithmetics */
1694         projPixel->image_index = projima - ps->projImages;
1695
1696         return projPixel;
1697 }
1698
1699 static bool line_clip_rect2f(
1700         const rctf *cliprect,
1701         const rctf *rect,
1702         const float l1[2], const float l2[2],
1703         float l1_clip[2], float l2_clip[2])
1704 {
1705         /* first account for horizontal, then vertical lines */
1706         /* horiz */
1707         if (fabsf(l1[1] - l2[1]) < PROJ_PIXEL_TOLERANCE) {
1708                 /* is the line out of range on its Y axis? */
1709                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1710                         return 0;
1711                 }
1712                 /* line is out of range on its X axis */
1713                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1714                         return 0;
1715                 }
1716
1717
1718                 if (fabsf(l1[0] - l2[0]) < PROJ_PIXEL_TOLERANCE) { /* this is a single point  (or close to)*/
1719                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1720                                 copy_v2_v2(l1_clip, l1);
1721                                 copy_v2_v2(l2_clip, l2);
1722                                 return 1;
1723                         }
1724                         else {
1725                                 return 0;
1726                         }
1727                 }
1728
1729                 copy_v2_v2(l1_clip, l1);
1730                 copy_v2_v2(l2_clip, l2);
1731                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1732                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1733                 return 1;
1734         }
1735         else if (fabsf(l1[0] - l2[0]) < PROJ_PIXEL_TOLERANCE) {
1736                 /* is the line out of range on its X axis? */
1737                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1738                         return 0;
1739                 }
1740
1741                 /* line is out of range on its Y axis */
1742                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1743                         return 0;
1744                 }
1745
1746                 if (fabsf(l1[1] - l2[1]) < PROJ_PIXEL_TOLERANCE) { /* this is a single point  (or close to)*/
1747                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1748                                 copy_v2_v2(l1_clip, l1);
1749                                 copy_v2_v2(l2_clip, l2);
1750                                 return 1;
1751                         }
1752                         else {
1753                                 return 0;
1754                         }
1755                 }
1756
1757                 copy_v2_v2(l1_clip, l1);
1758                 copy_v2_v2(l2_clip, l2);
1759                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1760                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1761                 return 1;
1762         }
1763         else {
1764                 float isect;
1765                 short ok1 = 0;
1766                 short ok2 = 0;
1767
1768                 /* Done with vertical lines */
1769
1770                 /* are either of the points inside the rectangle ? */
1771                 if (BLI_rctf_isect_pt_v(rect, l1)) {
1772                         copy_v2_v2(l1_clip, l1);
1773                         ok1 = 1;
1774                 }
1775
1776                 if (BLI_rctf_isect_pt_v(rect, l2)) {
1777                         copy_v2_v2(l2_clip, l2);
1778                         ok2 = 1;
1779                 }
1780
1781                 /* line inside rect */
1782                 if (ok1 && ok2) return 1;
1783
1784                 /* top/bottom */
1785                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= cliprect->xmin) && (isect <= cliprect->xmax)) {
1786                         if (l1[1] < l2[1]) { /* line 1 is outside */
1787                                 l1_clip[0] = isect;
1788                                 l1_clip[1] = rect->ymin;
1789                                 ok1 = 1;
1790                         }
1791                         else {
1792                                 l2_clip[0] = isect;
1793                                 l2_clip[1] = rect->ymin;
1794                                 ok2 = 2;
1795                         }
1796                 }
1797
1798                 if (ok1 && ok2) return 1;
1799
1800                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= cliprect->xmin) && (isect <= cliprect->xmax)) {
1801                         if (l1[1] > l2[1]) { /* line 1 is outside */
1802                                 l1_clip[0] = isect;
1803                                 l1_clip[1] = rect->ymax;
1804                                 ok1 = 1;
1805                         }
1806                         else {
1807                                 l2_clip[0] = isect;
1808                                 l2_clip[1] = rect->ymax;
1809                                 ok2 = 2;
1810                         }
1811                 }
1812
1813                 if (ok1 && ok2) return 1;
1814
1815                 /* left/right */
1816                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= cliprect->ymin) && (isect <= cliprect->ymax)) {
1817                         if (l1[0] < l2[0]) { /* line 1 is outside */
1818                                 l1_clip[0] = rect->xmin;
1819                                 l1_clip[1] = isect;
1820                                 ok1 = 1;
1821                         }
1822                         else {
1823                                 l2_clip[0] = rect->xmin;
1824                                 l2_clip[1] = isect;
1825                                 ok2 = 2;
1826                         }
1827                 }
1828
1829                 if (ok1 && ok2) return 1;
1830
1831                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= cliprect->ymin) && (isect <= cliprect->ymax)) {
1832                         if (l1[0] > l2[0]) { /* line 1 is outside */
1833                                 l1_clip[0] = rect->xmax;
1834                                 l1_clip[1] = isect;
1835                                 ok1 = 1;
1836                         }
1837                         else {
1838                                 l2_clip[0] = rect->xmax;
1839                                 l2_clip[1] = isect;
1840                                 ok2 = 2;
1841                         }
1842                 }
1843
1844                 if (ok1 && ok2) {
1845                         return 1;
1846                 }
1847                 else {
1848                         return 0;
1849                 }
1850         }
1851 }
1852
1853
1854
1855 /**
1856  * Scale the tri about its center
1857  * scaling by #PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1858  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces
1859  */
1860 #ifndef PROJ_DEBUG_NOSEAMBLEED
1861
1862 static void scale_tri(float insetCos[3][3], const float *origCos[4], const float inset)
1863 {
1864         float cent[3];
1865         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) * (1.0f / 3.0f);
1866         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) * (1.0f / 3.0f);
1867         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) * (1.0f / 3.0f);
1868
1869         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1870         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1871         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1872
1873         mul_v3_fl(insetCos[0], inset);
1874         mul_v3_fl(insetCos[1], inset);
1875         mul_v3_fl(insetCos[2], inset);
1876
1877         add_v3_v3(insetCos[0], cent);
1878         add_v3_v3(insetCos[1], cent);
1879         add_v3_v3(insetCos[2], cent);
1880 }
1881 #endif //PROJ_DEBUG_NOSEAMBLEED
1882
1883 static float len_squared_v2v2_alt(const float v1[2], const float v2_1, const float v2_2)
1884 {
1885         float x, y;
1886
1887         x = v1[0] - v2_1;
1888         y = v1[1] - v2_2;
1889         return x * x + y * y;
1890 }
1891
1892 /* note, use a squared value so we can use len_squared_v2v2
1893  * be sure that you have done a bounds check first or this may fail */
1894 /* only give bucket_bounds as an arg because we need it elsewhere */
1895 static bool project_bucket_isect_circle(const float cent[2], const float radius_squared, const rctf *bucket_bounds)
1896 {
1897
1898         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect
1899          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1900          * this is even less work then an intersection test
1901          */
1902 #if 0
1903         if (BLI_rctf_isect_pt_v(bucket_bounds, cent))
1904                 return 1;
1905 #endif
1906
1907         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1908             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1909         {
1910                 return 1;
1911         }
1912
1913         /* out of bounds left */
1914         if (cent[0] < bucket_bounds->xmin) {
1915                 /* lower left out of radius test */
1916                 if (cent[1] < bucket_bounds->ymin) {
1917                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1918                 }
1919                 /* top left test */
1920                 else if (cent[1] > bucket_bounds->ymax) {
1921                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1922                 }
1923         }
1924         else if (cent[0] > bucket_bounds->xmax) {
1925                 /* lower right out of radius test */
1926                 if (cent[1] < bucket_bounds->ymin) {
1927                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1928                 }
1929                 /* top right test */
1930                 else if (cent[1] > bucket_bounds->ymax) {
1931                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1932                 }
1933         }
1934
1935         return 0;
1936 }
1937
1938
1939
1940 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1941  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1942  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1943  * (viewed from the side)
1944  *
1945  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1946  * funcs that only account for points inside the triangle.
1947  * however switching back to this for ortho is always an option */
1948
1949 static void rect_to_uvspace_ortho(
1950         const rctf *bucket_bounds,
1951         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1952         const float *uv1co, const float *uv2co, const float *uv3co,
1953         float bucket_bounds_uv[4][2],
1954         const int flip)
1955 {
1956         float uv[2];
1957         float w[3];
1958
1959         /* get the UV space bounding box */
1960         uv[0] = bucket_bounds->xmax;
1961         uv[1] = bucket_bounds->ymin;
1962         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1963         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1964
1965         //uv[0] = bucket_bounds->xmax; // set above
1966         uv[1] = bucket_bounds->ymax;
1967         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1968         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1969
1970         uv[0] = bucket_bounds->xmin;
1971         //uv[1] = bucket_bounds->ymax; // set above
1972         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1973         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1974
1975         //uv[0] = bucket_bounds->xmin; // set above
1976         uv[1] = bucket_bounds->ymin;
1977         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1978         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1979 }
1980
1981 /* same as above but use barycentric_weights_v2_persp */
1982 static void rect_to_uvspace_persp(
1983         const rctf *bucket_bounds,
1984         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1985         const float *uv1co, const float *uv2co, const float *uv3co,
1986         float bucket_bounds_uv[4][2],
1987         const int flip
1988         )
1989 {
1990         float uv[2];
1991         float w[3];
1992
1993         /* get the UV space bounding box */
1994         uv[0] = bucket_bounds->xmax;
1995         uv[1] = bucket_bounds->ymin;
1996         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1997         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1998
1999         //uv[0] = bucket_bounds->xmax; // set above
2000         uv[1] = bucket_bounds->ymax;
2001         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2002         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
2003
2004         uv[0] = bucket_bounds->xmin;
2005         //uv[1] = bucket_bounds->ymax; // set above
2006         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2007         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
2008
2009         //uv[0] = bucket_bounds->xmin; // set above
2010         uv[1] = bucket_bounds->ymin;
2011         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2012         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
2013 }
2014
2015 /* This works as we need it to but we can save a few steps and not use it */
2016
2017 #if 0
2018 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
2019 {
2020         float v1[2], v2[2];
2021
2022         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
2023         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
2024
2025         return -atan2f(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
2026 }
2027 #endif
2028
2029 #define ISECT_1 (1)
2030 #define ISECT_2 (1 << 1)
2031 #define ISECT_3 (1 << 2)
2032 #define ISECT_4 (1 << 3)
2033 #define ISECT_ALL3 ((1 << 3) - 1)
2034 #define ISECT_ALL4 ((1 << 4) - 1)
2035
2036 /* limit must be a fraction over 1.0f */
2037 static bool IsectPT2Df_limit(
2038         const float pt[2],
2039         const float v1[2], const float v2[2], const float v3[2],
2040         const float limit)
2041 {
2042         return ((area_tri_v2(pt, v1, v2) +
2043                  area_tri_v2(pt, v2, v3) +
2044                  area_tri_v2(pt, v3, v1)) / (area_tri_v2(v1, v2, v3))) < limit;
2045 }
2046
2047 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
2048  * so we have the clipped UV's to do pixel intersection tests with
2049  * */
2050 static int float_z_sort_flip(const void *p1, const void *p2)
2051 {
2052         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
2053 }
2054
2055 static int float_z_sort(const void *p1, const void *p2)
2056 {
2057         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
2058 }
2059
2060 /* assumes one point is within the rectangle */
2061 static bool line_rect_clip(
2062         const rctf *rect,
2063         const float l1[4], const float l2[4],
2064         const float uv1[2], const float uv2[2],
2065         float uv[2], bool is_ortho)
2066 {
2067         float min = FLT_MAX, tmp;
2068         float xlen = l2[0] - l1[0];
2069         float ylen = l2[1] - l1[1];
2070
2071         /* 0.1 might seem too much, but remember, this is pixels! */
2072         if (xlen > 0.1f) {
2073                 if ((l1[0] - rect->xmin) * (l2[0] - rect->xmin) <= 0) {
2074                         tmp = rect->xmin;
2075                         min = min_ff((tmp - l1[0]) / xlen, min);
2076                 }
2077                 else if ((l1[0] - rect->xmax) * (l2[0] - rect->xmax) < 0) {
2078                         tmp = rect->xmax;
2079                         min = min_ff((tmp - l1[0]) / xlen, min);
2080                 }
2081         }
2082
2083         if (ylen > 0.1f) {
2084                 if ((l1[1] - rect->ymin) * (l2[1] - rect->ymin) <= 0) {
2085                         tmp = rect->ymin;
2086                         min = min_ff((tmp - l1[1]) / ylen, min);
2087                 }
2088                 else if ((l1[1] - rect->ymax) * (l2[1] - rect->ymax) < 0) {
2089                         tmp = rect->ymax;
2090                         min = min_ff((tmp - l1[1]) / ylen, min);
2091                 }
2092         }
2093
2094         if (min == FLT_MAX)
2095                 return false;
2096
2097         tmp = (is_ortho) ? 1.0f : (l1[3] + min * (l2[3] - l1[3]));
2098
2099         uv[0] = (uv1[0] + min / tmp * (uv2[0] - uv1[0]));
2100         uv[1] = (uv1[1] + min / tmp * (uv2[1] - uv1[1]));
2101
2102         return true;
2103 }
2104
2105
2106 static void project_bucket_clip_face(
2107         const bool is_ortho, const bool is_flip_object,
2108         const rctf *cliprect,
2109         const rctf *bucket_bounds,
2110         const float *v1coSS, const float *v2coSS, const float *v3coSS,
2111         const float *uv1co, const float *uv2co, const float *uv3co,
2112         float bucket_bounds_uv[8][2],
2113         int *tot, bool cull)
2114 {
2115         int inside_bucket_flag = 0;
2116         int inside_face_flag = 0;
2117         int flip;
2118         bool collinear = false;
2119
2120         float bucket_bounds_ss[4][2];
2121
2122         /* detect pathological case where face the three vertices are almost collinear in screen space.
2123          * mostly those will be culled but when flood filling or with smooth shading it's a possibility */
2124         if (min_fff(dist_squared_to_line_v2(v1coSS, v2coSS, v3coSS),
2125                     dist_squared_to_line_v2(v2coSS, v3coSS, v1coSS),
2126                     dist_squared_to_line_v2(v3coSS, v1coSS, v2coSS)) < PROJ_PIXEL_TOLERANCE)
2127         {
2128                 collinear = true;
2129         }
2130
2131         /* get the UV space bounding box */
2132         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v1coSS);
2133         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v2coSS) << 1;
2134         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v3coSS) << 2;
2135
2136         if (inside_bucket_flag == ISECT_ALL3) {
2137                 /* is_flip_object is used here because we use the face winding */
2138                 flip = (((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != is_flip_object) !=
2139                         (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
2140
2141                 /* all screenspace points are inside the bucket bounding box,
2142                  * this means we don't need to clip and can simply return the UVs */
2143                 if (flip) { /* facing the back? */
2144                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
2145                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2146                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
2147                 }
2148                 else {
2149                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
2150                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2151                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
2152                 }
2153
2154                 *tot = 3;
2155                 return;
2156         }
2157         /* handle pathological case here, no need for further intersections below since tringle area is almost zero */
2158         if (collinear) {
2159                 int flag;
2160
2161                 (*tot) = 0;
2162
2163                 if (cull)
2164                         return;
2165
2166                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(bucket_bounds_uv[*tot], uv1co); (*tot)++; }
2167
2168                 flag = inside_bucket_flag & (ISECT_1 | ISECT_2);
2169                 if (flag && flag != (ISECT_1 | ISECT_2)) {
2170                         if (line_rect_clip(bucket_bounds, v1coSS, v2coSS, uv1co, uv2co, bucket_bounds_uv[*tot], is_ortho))
2171                                 (*tot)++;
2172                 }
2173
2174                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(bucket_bounds_uv[*tot], uv2co); (*tot)++; }
2175
2176                 flag = inside_bucket_flag & (ISECT_2 | ISECT_3);
2177                 if (flag && flag != (ISECT_2 | ISECT_3)) {
2178                         if (line_rect_clip(bucket_bounds, v2coSS, v3coSS, uv2co, uv3co, bucket_bounds_uv[*tot], is_ortho))
2179                                 (*tot)++;
2180                 }
2181
2182                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(bucket_bounds_uv[*tot], uv3co); (*tot)++; }
2183
2184                 flag = inside_bucket_flag & (ISECT_3 | ISECT_1);
2185                 if (flag && flag != (ISECT_3 | ISECT_1)) {
2186                         if (line_rect_clip(bucket_bounds, v3coSS, v1coSS, uv3co, uv1co, bucket_bounds_uv[*tot], is_ortho))
2187                                 (*tot)++;
2188                 }
2189
2190                 if ((*tot) < 3) {
2191                         /* no intersections to speak of, but more probable is that all face is just outside the
2192                          * rectangle and culled due to float precision issues. Since above tests have failed,
2193                          * just dump triangle as is for painting */
2194                         *tot = 0;
2195                         copy_v2_v2(bucket_bounds_uv[*tot], uv1co); (*tot)++;
2196                         copy_v2_v2(bucket_bounds_uv[*tot], uv2co); (*tot)++;
2197                         copy_v2_v2(bucket_bounds_uv[*tot], uv3co); (*tot)++;
2198                         return;
2199                 }
2200
2201                 return;
2202         }
2203
2204         /* get the UV space bounding box */
2205         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
2206         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
2207         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
2208         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
2209
2210         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
2211         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
2212         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
2213
2214         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
2215         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
2216         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
2217
2218         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
2219         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
2220         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
2221
2222         flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) !=
2223                 (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
2224
2225         if (inside_face_flag == ISECT_ALL4) {
2226                 /* bucket is totally inside the screenspace face, we can safely use weights */
2227
2228                 if (is_ortho) {
2229                         rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2230                 }
2231                 else {
2232                         rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2233                 }
2234
2235                 *tot = 4;
2236                 return;
2237         }
2238         else {
2239                 /* The Complicated Case!
2240                  *
2241                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
2242                  *
2243                  * we need to make a convex polyline from the intersection between the screenspace face
2244                  * and the bucket bounds.
2245                  *
2246                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
2247                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
2248                  * do a correct clipping on both shapes. */
2249
2250
2251                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
2252
2253
2254
2255                 /* Maximum possible 6 intersections when using a rectangle and triangle */
2256                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
2257                 float v1_clipSS[2], v2_clipSS[2];
2258                 float w[3];
2259
2260                 /* calc center */
2261                 float cent[2] = {0.0f, 0.0f};
2262                 /*float up[2] = {0.0f, 1.0f};*/
2263                 int i;
2264                 bool doubles;
2265
2266                 (*tot) = 0;
2267
2268                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
2269                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
2270                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
2271                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
2272
2273                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
2274                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
2275                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
2276
2277                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
2278                         if (line_clip_rect2f(cliprect, bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
2279                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2280                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2281                         }
2282                 }
2283
2284                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
2285                         if (line_clip_rect2f(cliprect, bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
2286                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2287                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2288                         }
2289                 }
2290
2291                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
2292                         if (line_clip_rect2f(cliprect, bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
2293                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2294                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2295                         }
2296                 }
2297
2298
2299                 if ((*tot) < 3) { /* no intersections to speak of */
2300                         *tot = 0;
2301                         return;
2302                 }
2303
2304                 /* now we have all points we need, collect their angles and sort them clockwise */
2305
2306                 for (i = 0; i < (*tot); i++) {
2307                         cent[0] += isectVCosSS[i][0];
2308                         cent[1] += isectVCosSS[i][1];
2309                 }
2310                 cent[0] = cent[0] / (float)(*tot);
2311                 cent[1] = cent[1] / (float)(*tot);
2312
2313
2314
2315                 /* Collect angles for every point around the center point */
2316
2317
2318 #if 0   /* uses a few more cycles then the above loop */
2319                 for (i = 0; i < (*tot); i++) {
2320                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
2321                 }
2322 #endif
2323
2324                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
2325                 v1_clipSS[1] = cent[1] + 1.0f;
2326
2327                 for (i = 0; i < (*tot); i++) {
2328                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2329                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2330                         isectVCosSS[i][2] = atan2f(v1_clipSS[0] * v2_clipSS[1] - v1_clipSS[1] * v2_clipSS[0],
2331                                                    v1_clipSS[0] * v2_clipSS[0] + v1_clipSS[1] * v2_clipSS[1]);
2332                 }
2333
2334                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
2335                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
2336
2337                 doubles = true;
2338                 while (doubles == true) {
2339                         doubles = false;
2340
2341                         for (i = 0; i < (*tot); i++) {
2342                                 if (fabsf(isectVCosSS[(i + 1) % *tot][0] - isectVCosSS[i][0]) < PROJ_PIXEL_TOLERANCE &&
2343                                     fabsf(isectVCosSS[(i + 1) % *tot][1] - isectVCosSS[i][1]) < PROJ_PIXEL_TOLERANCE)
2344                                 {
2345                                         int j;
2346                                         for (j = i; j < (*tot) - 1; j++) {
2347                                                 isectVCosSS[j][0] = isectVCosSS[j + 1][0];
2348                                                 isectVCosSS[j][1] = isectVCosSS[j + 1][1];
2349                                         }
2350                                         doubles = true; /* keep looking for more doubles */
2351                                         (*tot)--;
2352                                 }
2353                         }
2354
2355                         /* its possible there is only a few left after remove doubles */
2356                         if ((*tot) < 3) {
2357                                 // printf("removed too many doubles B\n");
2358                                 *tot = 0;
2359                                 return;
2360                         }
2361                 }
2362
2363                 if (is_ortho) {
2364                         for (i = 0; i < (*tot); i++) {
2365                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2366                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2367                         }
2368                 }
2369                 else {
2370                         for (i = 0; i < (*tot); i++) {
2371                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2372                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2373                         }
2374                 }
2375         }
2376
2377 #ifdef PROJ_DEBUG_PRINT_CLIP
2378         /* include this at the bottom of the above function to debug the output */
2379
2380         {
2381                 /* If there are ever any problems, */
2382                 float test_uv[4][2];
2383                 int i;
2384                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2385                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2386                 printf("(  [(%f,%f), (%f,%f), (%f,%f), (%f,%f)], ",
2387                        test_uv[0][0], test_uv[0][1],   test_uv[1][0], test_uv[1][1],
2388                        test_uv[2][0], test_uv[2][1],    test_uv[3][0], test_uv[3][1]);
2389
2390                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2391
2392                 printf("[");
2393                 for (i = 0; i < (*tot); i++) {
2394                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2395                 }
2396                 printf("]),\\\n");
2397         }
2398 #endif
2399 }
2400
2401 /*
2402  * # This script creates faces in a blender scene from printed data above.
2403  *
2404  * project_ls = [
2405  * ...(output from above block)...
2406  * ]
2407  *
2408  * from Blender import Scene, Mesh, Window, sys, Mathutils
2409  *
2410  * import bpy
2411  *
2412  * V = Mathutils.Vector
2413  *
2414  * def main():
2415  *     sce = bpy.data.scenes.active
2416  *
2417  *     for item in project_ls:
2418  *         bb = item[0]
2419  *         uv = item[1]
2420  *         poly = item[2]
2421  *
2422  *         me = bpy.data.meshes.new()
2423  *         ob = sce.objects.new(me)
2424  *
2425  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2426  *         me.faces.extend([(0,1,2,3),])
2427  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2428  *         me.faces.extend([(4,5,6),])
2429  *
2430  *         vs = [V(p).xyz for p in poly]
2431  *         print len(vs)
2432  *         l = len(me.verts)
2433  *         me.verts.extend(vs)
2434  *
2435  *         i = l
2436  *         while i < len(me.verts):
2437  *             ii = i + 1
2438  *             if ii == len(me.verts):
2439  *                 ii = l
2440  *             me.edges.extend([i, ii])
2441  *             i += 1
2442  *
2443  * if __name__ == '__main__':
2444  *     main()
2445  */
2446
2447
2448 #undef ISECT_1
2449 #undef ISECT_2
2450 #undef ISECT_3
2451 #undef ISECT_4
2452 #undef ISECT_ALL3
2453 #undef ISECT_ALL4
2454
2455
2456 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2457  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2458 static bool IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2459 {
2460         int i;
2461         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2462                 return 0;
2463
2464         for (i = 1; i < tot; i++) {
2465                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2466                         return 0;
2467
2468         }
2469
2470         return 1;
2471 }
2472 static bool IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2473 {
2474         int i;
2475         bool side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2476
2477         for (i = 1; i < tot; i++) {
2478                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2479                         return 0;
2480
2481         }
2482
2483         return 1;
2484 }
2485
2486 /* One of the most important function for projection painting,
2487  * since it selects the pixels to be added into each bucket.
2488  *
2489  * initialize pixels from this face where it intersects with the bucket_index,
2490  * optionally initialize pixels for removing seams */
2491 static void project_paint_face_init(
2492         const ProjPaintState *ps,
2493         const int thread_index, const int bucket_index, const int tri_index, const int image_index,
2494         const rctf *clip_rect, const rctf *bucket_bounds, ImBuf *ibuf, ImBuf **tmpibuf,
2495         const bool clamp_u, const bool clamp_v)
2496 {
2497         /* Projection vars, to get the 3D locations into screen space  */
2498         MemArena *arena = ps->arena_mt[thread_index];
2499         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2500         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2501         bool threaded = (ps->thread_tot > 1);
2502
2503         TileInfo tinf = {
2504                 ps->tile_lock,
2505                 ps->do_masking,
2506                 IMAPAINT_TILE_NUMBER(ibuf->x),
2507                 tmpibuf,
2508                 ps->projImages + image_index
2509         };
2510
2511         const MLoopTri *lt = &ps->dm_mlooptri[tri_index];
2512         const int lt_vtri[3] = { PS_LOOPTRI_AS_VERT_INDEX_3(ps, lt) };
2513         const float *lt_tri_uv[3] = { PS_LOOPTRI_AS_UV_3(ps->dm_mloopuv, lt) };
2514
2515         /* UV/pixel seeking data */
2516         int x; /* Image X-Pixel */
2517         int y; /* Image Y-Pixel */
2518         float mask;
2519         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2520
2521         const float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to lt_vtri[0-2] */
2522
2523         const float *vCo[3]; /* vertex screenspace coords */
2524
2525         float w[3], wco[3];
2526
2527         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 */
2528         float pixelScreenCo[4];
2529         bool do_3d_mapping = ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D;
2530
2531         rcti bounds_px; /* ispace bounds */
2532         /* vars for getting uvspace bounds */
2533
2534         float lt_uv_pxoffset[3][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2535         float xhalfpx, yhalfpx;
2536         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2537
2538         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2539
2540         float uv_clip[8][2];
2541         int uv_clip_tot;
2542         const bool is_ortho = ps->is_ortho;
2543         const bool is_flip_object = ps->is_flip_object;
2544         const bool do_backfacecull = ps->do_backfacecull;
2545         const bool do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2546
2547         vCo[0] = ps->dm_mvert[lt_vtri[0]].co;
2548         vCo[1] = ps->dm_mvert[lt_vtri[1]].co;
2549         vCo[2] = ps->dm_mvert[lt_vtri[2]].co;
2550
2551
2552         /* Use lt_uv_pxoffset instead of lt_tri_uv so we can offset the UV half a pixel
2553          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2554          * problems when wrapping negative coords */
2555         xhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 3.0f))) / ibuf_xf;
2556         yhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 4.0f))) / ibuf_yf;
2557
2558         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2559          * Needed to add this offset since UV coords are often quads aligned to pixels.
2560          * In this case pixels can be exactly between 2 triangles causing nasty
2561          * artifacts.
2562          *
2563          * This workaround can be removed and painting will still work on most cases
2564          * but since the first thing most people try is painting onto a quad- better make it work.
2565          */
2566
2567         lt_uv_pxoffset[0][0] = lt_tri_uv[0][0] - xhalfpx;
2568         lt_uv_pxoffset[0][1] = lt_tri_uv[0][1] - yhalfpx;
2569
2570         lt_uv_pxoffset[1][0] = lt_tri_uv[1][0] - xhalfpx;
2571         lt_uv_pxoffset[1][1] = lt_tri_uv[1][1] - yhalfpx;
2572
2573         lt_uv_pxoffset[2][0] = lt_tri_uv[2][0] - xhalfpx;
2574         lt_uv_pxoffset[2][1] = lt_tri_uv[2][1] - yhalfpx;
2575
2576         {
2577                 uv1co = lt_uv_pxoffset[0]; // was lt_tri_uv[i1];
2578                 uv2co = lt_uv_pxoffset[1]; // was lt_tri_uv[i2];
2579                 uv3co = lt_uv_pxoffset[2]; // was lt_tri_uv[i3];
2580
2581                 v1coSS = ps->screenCoords[lt_vtri[0]];
2582                 v2coSS = ps->screenCoords[lt_vtri[1]];
2583                 v3coSS = ps->screenCoords[lt_vtri[2]];
2584
2585                 /* This funtion gives is a concave polyline in UV space from the clipped tri*/
2586                 project_bucket_clip_face(
2587                         is_ortho, is_flip_object,
2588                         clip_rect, bucket_bounds,
2589                         v1coSS, v2coSS, v3coSS,
2590                         uv1co, uv2co, uv3co,
2591                         uv_clip, &uv_clip_tot,
2592                         do_backfacecull || ps->do_occlude);
2593
2594                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2595 #if 0
2596                 if (uv_clip_tot > 6) {
2597                         printf("this should never happen! %d\n", uv_clip_tot);
2598                 }
2599 #endif
2600
2601                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2602
2603                         if (clamp_u) {
2604                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2605                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2606                         }
2607
2608                         if (clamp_v) {
2609                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2610                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2611                         }
2612
2613 #if 0
2614                         project_paint_undo_tiles_init(&bounds_px, ps->projImages + image_index, tmpibuf,
2615                                                       tile_width, threaded, ps->do_masking);
2616 #endif
2617                         /* clip face and */
2618
2619                         has_isect = 0;
2620                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2621                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2622                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2623
2624                                 has_x_isect = 0;
2625                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2626                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2627                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2628
2629                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2630                                          * could check the poly direction but better to do this */
2631                                         if ((do_backfacecull == true  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2632                                             (do_backfacecull == false && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2633                                         {
2634
2635                                                 has_x_isect = has_isect = 1;
2636
2637                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2638                                                 else screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2639
2640                                                 /* a pity we need to get the worldspace pixel location here */
2641                                                 if (do_clip || do_3d_mapping) {
2642                                                         interp_v3_v3v3v3(
2643                                                                 wco,
2644                                                                 ps->dm_mvert[lt_vtri[0]].co,
2645                                                                 ps->dm_mvert[lt_vtri[1]].co,
2646                                                                 ps->dm_mvert[lt_vtri[2]].co,
2647                                                                 w);
2648                                                         if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2649                                                                 continue; /* Watch out that no code below this needs to run */
2650                                                         }
2651                                                 }
2652
2653                                                 /* Is this UV visible from the view? - raytrace */
2654                                                 /* project_paint_PickFace is less complex, use for testing */
2655                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == tri_index) {
2656                                                 if ((ps->do_occlude == false) ||
2657                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, tri_index, pixelScreenCo))
2658                                                 {
2659                                                         mask = project_paint_uvpixel_mask(ps, tri_index, w);
2660
2661                                                         if (mask > 0.0f) {
2662                                                                 BLI_linklist_prepend_arena(
2663                                                                         bucketPixelNodes,
2664                                                                         project_paint_uvpixel_init(ps, arena, &tinf, x, y, mask, tri_index,
2665                                                                                                    pixelScreenCo, wco, w),
2666                                                                         arena
2667                                                                         );
2668                                                         }
2669                                                 }
2670
2671                                         }
2672 //#if 0
2673                                         else if (has_x_isect) {
2674                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2675                                                 break;
2676                                         }
2677 //#endif
2678                                 }
2679
2680
2681 #if 0           /* TODO - investigate why this dosnt work sometimes! it should! */
2682                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2683                                 if (has_x_isect == 0 && has_isect) {
2684                                         break;
2685                                 }
2686 #endif
2687                         }
2688                 }
2689         }
2690
2691
2692 #ifndef PROJ_DEBUG_NOSEAMBLEED
2693         if (ps->seam_bleed_px > 0.0f) {
2694                 int face_seam_flag;
2695
2696                 if (threaded)
2697                         BLI_thread_lock(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2698
2699                 face_seam_flag = ps->faceSeamFlags[tri_index];
2700
2701                 /* are any of our edges un-initialized? */
2702                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_NOSEAM1)) == 0 ||
2703                     (face_seam_flag & (PROJ_FACE_SEAM2 | PROJ_FACE_NOSEAM2)) == 0 ||
2704                     (face_seam_flag & (PROJ_FACE_SEAM3 | PROJ_FACE_NOSEAM3)) == 0)
2705                 {
2706                         project_face_seams_init(ps, tri_index);
2707                         face_seam_flag = ps->faceSeamFlags[tri_index];
2708                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3);
2709                 }
2710
2711                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_SEAM2 | PROJ_FACE_SEAM3)) == 0) {
2712
2713                         if (threaded)
2714                                 BLI_thread_unlock(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2715
2716                 }
2717                 else {
2718                         /* we have a seam - deal with it! */
2719
2720                         /* Now create new UV's for the seam face */
2721                         float (*outset_uv)[2] = ps->faceSeamUVs[tri_index];
2722                         float insetCos[3][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2723
2724                         const float *vCoSS[3]; /* vertex screenspace coords */
2725
2726                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2727                         float edge_verts_inset_clip[2][3];
2728                         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 */
2729
2730                         float seam_subsection[4][2];
2731                         float fac1, fac2;
2732
2733                         if (outset_uv[0][0] == FLT_MAX) /* first time initialize */
2734                                 uv_image_outset(
2735                                         lt_uv_pxoffset, outset_uv, ps->seam_bleed_px,
2736                                         ibuf->x, ibuf->y, (ps->faceWindingFlags[tri_index] & PROJ_FACE_WINDING_CW) == 0);
2737
2738                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2739                         if (threaded)
2740                                 BLI_thread_unlock(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2741
2742                         vCoSS[0] = ps->screenCoords[lt_vtri[0]];
2743                         vCoSS[1] = ps->screenCoords[lt_vtri[1]];
2744                         vCoSS[2] = ps->screenCoords[lt_vtri[2]];
2745
2746                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2747                         if (is_ortho) {
2748                                 scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2749                         }
2750                         else {
2751                                 scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2752                         }
2753
2754                         for (fidx1 = 0; fidx1 < 3; fidx1++) {
2755                                 fidx2 = (fidx1 == 2) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2) -> (1,2,0) */
2756
2757                                 if ((face_seam_flag & (1 << fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2758                                     line_clip_rect2f(clip_rect, bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1]))
2759                                 {
2760                                         if (len_squared_v2v2(vCoSS[fidx1], vCoSS[fidx2]) > FLT_EPSILON) { /* avoid div by zero */
2761
2762                                                 if (is_ortho) {
2763                                                         fac1 = line_point_factor_v2(bucket_clip_edges[0], vCoSS[fidx1], vCoSS[fidx2]);
2764                                                         fac2 = line_point_factor_v2(bucket_clip_edges[1], vCoSS[fidx1], vCoSS[fidx2]);
2765                                                 }
2766                                                 else {
2767                                                         fac1 = screen_px_line_point_factor_v2_persp(ps, bucket_clip_edges[0], vCo[fidx1], vCo[fidx2]);
2768                                                         fac2 = screen_px_line_point_factor_v2_persp(ps, bucket_clip_edges[1], vCo[fidx1], vCo[fidx2]);
2769                                                 }
2770
2771                                                 interp_v2_v2v2(seam_subsection[0], lt_uv_pxoffset[fidx1], lt_uv_pxoffset[fidx2], fac1);
2772                                                 interp_v2_v2v2(seam_subsection[1], lt_uv_pxoffset[fidx1], lt_uv_pxoffset[fidx2], fac2);
2773
2774                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2775                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2776
2777                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2778                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2779                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2780                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2781
2782
2783                                                 if (pixel_bounds_uv(seam_subsection, &bounds_px, ibuf->x, ibuf->y)) {
2784                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2785
2786                                                         has_isect = 0;
2787                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2788                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2789                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2790
2791                                                                 has_x_isect = 0;
2792                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2793                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2794                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2795
2796                                                                         /* test we're inside uvspace bucket and triangle bounds */
2797                                                                         if (isect_point_quad_v2(uv, UNPACK4(seam_subsection))) {
2798                                                                                 float fac;
2799
2800                                                                                 /* We need to find the closest point along the face edge,
2801                                                                                  * getting the screen_px_from_*** wont work because our actual location
2802                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2803                                                                                  * our location on the side of the face's UV */
2804 #if 0
2805                                                                                 if (is_ortho) screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2806                                                                                 else          screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2807 #endif
2808
2809                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2810                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2811                                                                                 fac = resolve_quad_u_v2(uv, UNPACK4(seam_subsection));
2812                                                                                 interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac);
2813
2814                                                                                 if (!is_ortho) {
2815                                                                                         pixelScreenCo[3] = 1.0f;
2816                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2817                                                                                         pixelScreenCo[0] = (float)(ps->winx * 0.5f) + (ps->winx * 0.5f) * pixelScreenCo[0] / pixelScreenCo[3];
2818                                                                                         pixelScreenCo[1] = (float)(ps->winy * 0.5f) + (ps->winy * 0.5f) * pixelScreenCo[1] / pixelScreenCo[3];
2819                                                                                         pixelScreenCo[2] = pixelScreenCo[2] / pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2820                                                                                 }
2821
2822                                                                                 if ((ps->do_occlude == false) ||
2823                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, tri_index, pixelScreenCo))
2824                                                                                 {
2825                                                                                         /* Only bother calculating the weights if we intersect */
2826                                                                                         if (ps->do_mask_normal || ps->dm_mloopuv_clone) {
2827                                                                                                 const float uv_fac = fac1 + (fac * (fac2 - fac1));
2828 #if 0
2829                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2830                                                                                                 float uv_close[2];
2831                                                                                                 interp_v2_v2v2(uv_close, lt_uv_pxoffset[fidx1], lt_uv_pxoffset[fidx2], uv_fac);
2832                                                                                                 barycentric_weights_v2(lt_uv_pxoffset[0], lt_uv_pxoffset[1], lt_uv_pxoffset[2], uv_close, w);
2833 #else
2834
2835                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2836                                                                                                 w[0] = w[1] = w[2] = 0.0;
2837                                                                                                 w[fidx1] = 1.0f - uv_fac;
2838                                                                                                 w[fidx2] = uv_fac;
2839 #endif
2840                                                                                         }
2841
2842                                                                                         /* a pity we need to get the worldspace pixel location here */
2843                                                                                         if (do_clip || do_3d_mapping) {
2844                                                                                                 interp_v3_v3v3v3(wco, vCo[0], vCo[1], vCo[2], w);
2845
2846                                                                                                 if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2847                                                                                                         continue; /* Watch out that no code below this needs to run */
2848                                                                                                 }
2849                                                                                         }
2850
2851                                                                                         mask = project_paint_uvpixel_mask(ps, tri_index, w);
2852
2853                                                                                         if (mask > 0.0f) {
2854                                                                                                 BLI_linklist_prepend_arena(
2855                                                                                                         bucketPixelNodes,
2856                                                                                                         project_paint_uvpixel_init(ps, arena, &tinf, x, y, mask, tri_index,
2857                                                                                                         pixelScreenCo, wco, w),
2858                                                                                                         arena
2859                                                                                                         );
2860                                                                                         }
2861
2862                                                                                 }
2863                                                                         }
2864                                                                         else if (has_x_isect) {
2865                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2866                                                                                 break;
2867                                                                         }
2868                                                                 }
2869
2870 #if 0                           /* TODO - investigate why this dosnt work sometimes! it should! */
2871                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2872                                                                 if (has_x_isect == 0 && has_isect) {
2873                                                                         break;
2874                                                                 }
2875 #endif
2876                                                         }
2877                                                 }
2878                                         }
2879                                 }
2880                         }
2881                 }
2882         }
2883 #else
2884         UNUSED_VARS(vCo, threaded);
2885 #endif // PROJ_DEBUG_NOSEAMBLEED
2886 }
2887
2888
2889 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2890 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2891 {
2892         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2893         /* 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 */
2894         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 */
2895         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2896
2897         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2898         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2899
2900         /* in case the rect is outside the mesh 2d bounds */
2901         CLAMP(bucketMin[0], 0, ps->buckets_x);
2902         CLAMP(bucketMin[1], 0, ps->buckets_y);
2903
2904         CLAMP(bucketMax[0], 0, ps->buckets_x);
2905         CLAMP(bucketMax[1], 0, ps->buckets_y);
2906 }
2907
2908 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2909 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2910 {
2911         bucket_bounds->xmin = ps->screenMin[0] + ((bucket_x) * (ps->screen_width / ps->buckets_x));     /* left */
2912         bucket_bounds->xmax = ps->screenMin[0] + ((bucket_x + 1) * (ps->screen_width / ps->buckets_x)); /* right */
2913
2914         bucket_bounds->ymin = ps->screenMin[1] + ((bucket_y) * (ps->screen_height / ps->buckets_y));      /* bottom */
2915         bucket_bounds->ymax = ps->screenMin[1] + ((bucket_y + 1) * (ps->screen_height  / ps->buckets_y)); /* top */
2916 }
2917
2918 /* Fill this bucket with pixels from the faces that intersect it.
2919  *
2920  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2921 static void project_bucket_init(
2922         const ProjPaintState *ps, const int thread_index, const int bucket_index,
2923         const rctf *clip_rect, const rctf *bucket_bounds)
2924 {
2925         LinkNode *node;
2926         int tri_index, image_index = 0;
2927         ImBuf *ibuf = NULL;
2928         Image *tpage_last = NULL, *tpage;
2929         Image *ima = NULL;
2930         ImBuf *tmpibuf = NULL;
2931
2932         if (ps->image_tot == 1) {
2933                 /* Simple loop, no context switching */
2934                 ibuf = ps->projImages[0].ibuf;
2935                 ima = ps->projImages[0].ima;
2936
2937                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2938                   &