Project Paint: Add symmetry support
[blender-staging.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 "BLF_translation.h"
53
54
55 #include "IMB_imbuf.h"
56 #include "IMB_imbuf_types.h"
57
58 #include "DNA_brush_types.h"
59 #include "DNA_material_types.h"
60 #include "DNA_mesh_types.h"
61 #include "DNA_node_types.h"
62 #include "DNA_object_types.h"
63
64 #include "BKE_camera.h"
65 #include "BKE_context.h"
66 #include "BKE_colortools.h"
67 #include "BKE_depsgraph.h"
68 #include "BKE_DerivedMesh.h"
69 #include "BKE_idprop.h"
70 #include "BKE_brush.h"
71 #include "BKE_image.h"
72 #include "BKE_library.h"
73 #include "BKE_main.h"
74 #include "BKE_material.h"
75 #include "BKE_mesh.h"
76 #include "BKE_mesh_mapping.h"
77 #include "BKE_node.h"
78 #include "BKE_paint.h"
79 #include "BKE_report.h"
80 #include "BKE_scene.h"
81 #include "BKE_texture.h"
82
83 #include "UI_interface.h"
84
85 #include "ED_mesh.h"
86 #include "ED_node.h"
87 #include "ED_paint.h"
88 #include "ED_screen.h"
89 #include "ED_uvedit.h"
90 #include "ED_view3d.h"
91
92 #include "GPU_extensions.h"
93
94 #include "WM_api.h"
95 #include "WM_types.h"
96
97 #include "RNA_access.h"
98 #include "RNA_define.h"
99 #include "RNA_enum_types.h"
100
101 #include "GPU_draw.h"
102
103 #include "IMB_colormanagement.h"
104
105 #include "bmesh.h"
106 //#include "bmesh_tools.h"
107
108 #include "paint_intern.h"
109
110 /* Defines and Structs */
111 /* FTOCHAR as inline function */
112 BLI_INLINE unsigned char f_to_char(const float val)
113 {
114         return FTOCHAR(val);
115 }
116
117 /* ProjectionPaint defines */
118
119 /* approx the number of buckets to have under the brush,
120  * used with the brush size to set the ps->buckets_x and ps->buckets_y value.
121  *
122  * When 3 - a brush should have ~9 buckets under it at once
123  * ...this helps for threading while painting as well as
124  * avoiding initializing pixels that wont touch the brush */
125 #define PROJ_BUCKET_BRUSH_DIV 4
126
127 #define PROJ_BUCKET_RECT_MIN 4
128 #define PROJ_BUCKET_RECT_MAX 256
129
130 #define PROJ_BOUNDBOX_DIV 8
131 #define PROJ_BOUNDBOX_SQUARED  (PROJ_BOUNDBOX_DIV * PROJ_BOUNDBOX_DIV)
132
133 //#define PROJ_DEBUG_PAINT 1
134 //#define PROJ_DEBUG_NOSEAMBLEED 1
135 //#define PROJ_DEBUG_PRINT_CLIP 1
136 #define PROJ_DEBUG_WINCLIP 1
137
138
139 #ifndef PROJ_DEBUG_NOSEAMBLEED
140 /* projectFaceSeamFlags options */
141 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
142 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
143 #define PROJ_FACE_SEAM1 (1 << 0)  /* If this face has a seam on any of its edges */
144 #define PROJ_FACE_SEAM2 (1 << 1)
145 #define PROJ_FACE_SEAM3 (1 << 2)
146 #define PROJ_FACE_SEAM4 (1 << 3)
147
148 #define PROJ_FACE_NOSEAM1   (1 << 4)
149 #define PROJ_FACE_NOSEAM2   (1 << 5)
150 #define PROJ_FACE_NOSEAM3   (1 << 6)
151 #define PROJ_FACE_NOSEAM4   (1 << 7)
152
153 /* face winding */
154 #define PROJ_FACE_WINDING_INIT 1
155 #define PROJ_FACE_WINDING_CW 2
156
157 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
158  * as this number approaches  1.0f the likelihood increases of float precision errors where
159  * it is occluded by an adjacent face */
160 #define PROJ_FACE_SCALE_SEAM    0.99f
161 #endif  /* PROJ_DEBUG_NOSEAMBLEED */
162
163
164 #define PROJ_SRC_VIEW       1
165 #define PROJ_SRC_IMAGE_CAM  2
166 #define PROJ_SRC_IMAGE_VIEW 3
167 #define PROJ_SRC_VIEW_FILL  4
168
169 #define PROJ_VIEW_DATA_ID "view_data"
170 #define PROJ_VIEW_DATA_SIZE (4 * 4 + 4 * 4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
171
172 #define PROJ_BUCKET_NULL        0
173 #define PROJ_BUCKET_INIT        (1 << 0)
174 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
175
176 /* used for testing doubles, if a point is on a line etc */
177 #define PROJ_GEOM_TOLERANCE 0.00075f
178 #define PROJ_PIXEL_TOLERANCE 0.01f
179
180 /* vert flags */
181 #define PROJ_VERT_CULL 1
182
183 /* to avoid locking in tile initialization */
184 #define TILE_PENDING SET_INT_IN_POINTER(-1)
185
186 /* This is mainly a convenience struct used so we can keep an array of images we use
187  * Thir imbufs, etc, in 1 array, When using threads this array is copied for each thread
188  * because 'partRedrawRect' and 'touch' values would not be thread safe */
189 typedef struct ProjPaintImage {
190         Image *ima;
191         ImBuf *ibuf;
192         ImagePaintPartialRedraw *partRedrawRect;
193         volatile void **undoRect; /* only used to build undo tiles during painting */
194         unsigned short **maskRect; /* the mask accumulation must happen on canvas, not on space screen bucket.
195                                     * Here we store the mask rectangle */
196         bool **valid; /* store flag to enforce validation of undo rectangle */
197         bool touch;
198 } ProjPaintImage;
199
200 /**
201  * Handle for stroke (operator customdata)
202  */
203 typedef struct ProjStrokeHandle {
204         /* Support for painting from multiple views at once,
205          * currently used to impliment summetry painting,
206          * we can assume at least the first is set while painting. */
207         struct ProjPaintState *ps_views[8];
208         int ps_views_tot;
209         int symmetry_flags;
210
211         int orig_brush_size;
212
213         bool need_redraw;
214
215         /* trick to bypass regular paint and allow clone picking */
216         bool is_clone_cursor_pick;
217
218         /* In ProjPaintState, only here for convenience */
219         Scene *scene;
220         Brush *brush;
221 } ProjStrokeHandle;
222
223 /* Main projection painting struct passed to all projection painting functions */
224 typedef struct ProjPaintState {
225         View3D *v3d;
226         RegionView3D *rv3d;
227         ARegion *ar;
228         Scene *scene;
229         int source; /* PROJ_SRC_**** */
230
231         /* the paint color. It can change depending of inverted mode or not */
232         float paint_color[3];
233         float paint_color_linear[3];
234         float dither;
235
236         Brush *brush;
237         short tool, blend, mode;
238
239         float brush_size;
240         Object *ob;
241         /* for symmetry, we need to store modified object matrix */
242         float obmat[4][4];
243         float obmat_imat[4][4];
244         /* end similarities with ImagePaintState */
245
246         Image *stencil_ima;
247         Image *canvas_ima;
248         Image *clone_ima;
249         float stencil_value;
250
251         /* projection painting only */
252         MemArena *arena_mt[BLENDER_MAX_THREADS]; /* for multithreading, the first item is sometimes used for non threaded cases too */
253         LinkNode **bucketRect;              /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
254         LinkNode **bucketFaces;             /* bucketRect aligned array linkList of faces overlapping each bucket */
255         unsigned char *bucketFlags;         /* store if the bucks have been initialized  */
256
257         char *vertFlags;                    /* store options per vert, now only store if the vert is pointing away from the view */
258         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 */
259         int buckets_y;
260
261         int pixel_sizeof;           /* result of project_paint_pixel_sizeof(), constant per stroke */
262
263         int image_tot;              /* size of projectImages array */
264
265         float (*screenCoords)[4];   /* verts projected into floating point screen space */
266         float screenMin[2];         /* 2D bounds for mesh verts on the screen's plane (screenspace) */
267         float screenMax[2];
268         float screen_width;         /* Calculated from screenMin & screenMax */
269         float screen_height;
270         int winx, winy;             /* from the carea or from the projection render */
271
272         /* options for projection painting */
273         bool  do_layer_clone;
274         bool  do_layer_stencil;
275         bool  do_layer_stencil_inv;
276         bool  do_stencil_brush;
277         bool  do_material_slots;
278
279         bool  do_occlude;               /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
280         bool  do_backfacecull;          /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
281         bool  do_mask_normal;           /* mask out pixels based on their normals */
282         bool  do_mask_cavity;           /* mask out pixels based on cavity */
283         bool  do_new_shading_nodes;     /* cache BKE_scene_use_new_shading_nodes value */
284         float normal_angle;             /* what angle to mask at */
285         float normal_angle__cos;         /* cos(normal_angle), faster to compare */
286         float normal_angle_inner;
287         float normal_angle_inner__cos;
288         float normal_angle_range;       /* difference between normal_angle and normal_angle_inner, for easy access */
289
290         bool do_face_sel;               /* quick access to (me->editflag & ME_EDIT_PAINT_FACE_SEL) */
291         bool is_ortho;
292         bool is_flip_object;            /* the object is negative scaled */
293         bool do_masking;              /* use masking during painting. Some operations such as airbrush may disable */
294         bool is_texbrush;              /* only to avoid running  */
295         bool is_maskbrush;            /* mask brush is applied before masking */
296 #ifndef PROJ_DEBUG_NOSEAMBLEED
297         float seam_bleed_px;
298 #endif
299         /* clone vars */
300         float cloneOffset[2];
301
302         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
303         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
304         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
305         float clipsta, clipend;
306
307         /* reproject vars */
308         Image *reproject_image;
309         ImBuf *reproject_ibuf;
310
311         /* threads */
312         int thread_tot;
313         int bucketMin[2];
314         int bucketMax[2];
315         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
316
317         struct CurveMapping *cavity_curve;
318         BlurKernel *blurkernel;
319
320
321
322         /* -------------------------------------------------------------------- */
323         /* Vars shared between multiple views (keep last) */
324         /**
325          * This data is owned by ``ProjStrokeHandle.ps_views[0]``,
326          * all other views re-use the data.
327          */
328
329 #define PROJ_PAINT_STATE_SHARED_MEMCPY(ps_dst, ps_src) \
330         MEMCPY_STRUCT_OFS(ps_dst, ps_src, is_shared_user)
331
332 #define PROJ_PAINT_STATE_SHARED_CLEAR(ps) \
333         MEMSET_STRUCT_OFS(ps, 0, is_shared_user)
334
335         bool is_shared_user;
336
337         ProjPaintImage *projImages;
338         float *cavities;            /* cavity amount for vertices */
339
340 #ifndef PROJ_DEBUG_NOSEAMBLEED
341         char *faceSeamFlags;                /* store info about faces, if they are initialized etc*/
342         char *faceWindingFlags;             /* save the winding of the face in uv space, helps as an extra validation step for seam detection */
343         float (*faceSeamUVs)[4][2];         /* expanded UVs for faces to use as seams */
344         LinkNode **vertFaces;               /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
345 #endif
346
347         SpinLock *tile_lock;
348
349         DerivedMesh    *dm;
350         int dm_totface;
351         int dm_totedge;
352         int dm_totvert;
353         int dm_release;
354
355         MVert          *dm_mvert;
356         MEdge          *dm_medge;
357         MFace          *dm_mface;
358         MTFace         *dm_mtface_stencil;
359
360         MTFace         **dm_mtface;
361         MTFace         **dm_mtface_clone;    /* other UV map, use for cloning between layers */
362 } ProjPaintState;
363
364 typedef union pixelPointer {
365         float *f_pt;            /* float buffer */
366         unsigned int *uint_pt; /* 2 ways to access a char buffer */
367         unsigned char *ch_pt;
368 } PixelPointer;
369
370 typedef union pixelStore {
371         unsigned char ch[4];
372         unsigned int uint;
373         float f[4];
374 } PixelStore;
375
376 typedef struct ProjPixel {
377         float projCoSS[2]; /* the floating point screen projection of this pixel */
378         float worldCoSS[3];
379
380         short x_px, y_px;
381
382         unsigned short image_index; /* if anyone wants to paint onto more than 65535 images they can bite me */
383         unsigned char bb_cell_index;
384
385         /* for various reasons we may want to mask out painting onto this pixel */
386         unsigned short mask;
387
388         /* Only used when the airbrush is disabled.
389          * Store the max mask value to avoid painting over an area with a lower opacity
390          * with an advantage that we can avoid touching the pixel at all, if the
391          * new mask value is lower then mask_accum */
392         unsigned short *mask_accum;
393
394         /* horrible hack, store tile valid flag pointer here to re-validate tiles used for anchored and drag-dot strokes */
395         bool *valid;
396
397         PixelPointer origColor;
398         PixelStore newColor;
399         PixelPointer pixel;
400 } ProjPixel;
401
402 typedef struct ProjPixelClone {
403         struct ProjPixel __pp;
404         PixelStore clonepx;
405 } ProjPixelClone;
406
407 /* undo tile pushing */
408 typedef struct {
409         SpinLock *lock;
410         bool masked;
411         unsigned short tile_width;
412         ImBuf **tmpibuf;
413         ProjPaintImage *pjima;
414 } TileInfo;
415
416
417 /* Finish projection painting structs */
418
419 static TexPaintSlot *project_paint_face_paint_slot(const ProjPaintState *ps, int face_index)
420 {
421         MFace *mf = ps->dm_mface + face_index;
422         Material *ma = ps->dm->mat[mf->mat_nr];
423         return ma ? ma->texpaintslot + ma->paint_active_slot : NULL;
424 }
425
426 static Image *project_paint_face_paint_image(const ProjPaintState *ps, int face_index)
427 {
428         if (ps->do_stencil_brush) {
429                 return ps->stencil_ima;
430         }
431         else {
432                 MFace *mf = ps->dm_mface + face_index;
433                 Material *ma = ps->dm->mat[mf->mat_nr];
434                 TexPaintSlot *slot = ma ? ma->texpaintslot + ma->paint_active_slot : NULL;
435                 return slot ? slot->ima : ps->canvas_ima;
436         }
437 }
438
439 static TexPaintSlot *project_paint_face_clone_slot(const ProjPaintState *ps, int face_index)
440 {
441         MFace *mf = ps->dm_mface + face_index;
442         Material *ma = ps->dm->mat[mf->mat_nr];
443         return ma ? ma->texpaintslot + ma->paint_clone_slot : NULL;
444 }
445
446 static Image *project_paint_face_clone_image(const ProjPaintState *ps, int face_index)
447 {
448         MFace *mf = ps->dm_mface + face_index;
449         Material *ma = ps->dm->mat[mf->mat_nr];
450         TexPaintSlot *slot = ma ? ma->texpaintslot + ma->paint_clone_slot : NULL;
451         return slot ? slot->ima : ps->clone_ima;
452 }
453
454 /* fast projection bucket array lookup, use the safe version for bound checking  */
455 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
456 {
457         /* If we were not dealing with screenspace 2D coords we could simple do...
458          * ps->bucketRect[x + (y*ps->buckets_y)] */
459
460         /* please explain?
461          * projCoSS[0] - ps->screenMin[0]   : zero origin
462          * ... / ps->screen_width           : range from 0.0 to 1.0
463          * ... * ps->buckets_x              : use as a bucket index
464          *
465          * Second multiplication does similar but for vertical offset
466          */
467         return ( (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
468                (((int)(((projCoSS[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
469 }
470
471 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
472 {
473         int bucket_index = project_bucket_offset(ps, projCoSS);
474
475         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
476                 return -1;
477         }
478         else {
479                 return bucket_index;
480         }
481 }
482
483 static float VecZDepthOrtho(
484         const float pt[2],
485         const float v1[3], const float v2[3], const float v3[3],
486         float w[3])
487 {
488         barycentric_weights_v2(v1, v2, v3, pt, w);
489         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
490 }
491
492 static float VecZDepthPersp(
493         const float pt[2],
494         const float v1[4], const float v2[4], const float v3[4],
495         float w[3])
496 {
497         float wtot_inv, wtot;
498         float w_tmp[3];
499
500         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
501         /* for the depth we need the weights to match what
502          * barycentric_weights_v2 would return, in this case its easiest just to
503          * undo the 4th axis division and make it unit-sum
504          *
505          * don't call barycentric_weights_v2() because our callers expect 'w'
506          * to be weighted from the perspective */
507         w_tmp[0] = w[0] * v1[3];
508         w_tmp[1] = w[1] * v2[3];
509         w_tmp[2] = w[2] * v3[3];
510
511         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
512
513         if (wtot != 0.0f) {
514                 wtot_inv = 1.0f / wtot;
515
516                 w_tmp[0] = w_tmp[0] * wtot_inv;
517                 w_tmp[1] = w_tmp[1] * wtot_inv;
518                 w_tmp[2] = w_tmp[2] * wtot_inv;
519         }
520         else /* dummy values for zero area face */
521                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
522         /* done mimicing barycentric_weights_v2() */
523
524         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
525 }
526
527
528 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
529 static int project_paint_PickFace(
530         const ProjPaintState *ps, const float pt[2],
531         float w[3], int *r_side)
532 {
533         LinkNode *node;
534         float w_tmp[3];
535         const float *v1, *v2, *v3, *v4;
536         int bucket_index;
537         int face_index;
538         int best_side = -1;
539         int best_face_index = -1;
540         float z_depth_best = FLT_MAX, z_depth;
541         MFace *mf;
542
543         bucket_index = project_bucket_offset_safe(ps, pt);
544         if (bucket_index == -1)
545                 return -1;
546
547
548
549         /* we could return 0 for 1 face buckets, as long as this function assumes
550          * that the point its testing is only every originated from an existing face */
551
552         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
553                 face_index = GET_INT_FROM_POINTER(node->link);
554                 mf = ps->dm_mface + face_index;
555
556                 v1 = ps->screenCoords[mf->v1];
557                 v2 = ps->screenCoords[mf->v2];
558                 v3 = ps->screenCoords[mf->v3];
559
560                 if (isect_point_tri_v2(pt, v1, v2, v3)) {
561                         if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v2, v3, w_tmp);
562                         else z_depth = VecZDepthPersp(pt, v1, v2, v3, w_tmp);
563
564                         if (z_depth < z_depth_best) {
565                                 best_face_index = face_index;
566                                 best_side = 0;
567                                 z_depth_best = z_depth;
568                                 copy_v3_v3(w, w_tmp);
569                         }
570                 }
571                 else if (mf->v4) {
572                         v4 = ps->screenCoords[mf->v4];
573
574                         if (isect_point_tri_v2(pt, v1, v3, v4)) {
575                                 if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v3, v4, w_tmp);
576                                 else z_depth = VecZDepthPersp(pt, v1, v3, v4, w_tmp);
577
578                                 if (z_depth < z_depth_best) {
579                                         best_face_index = face_index;
580                                         best_side = 1;
581                                         z_depth_best = z_depth;
582                                         copy_v3_v3(w, w_tmp);
583                                 }
584                         }
585                 }
586         }
587
588         *r_side = best_side;
589         return best_face_index; /* will be -1 or a valid face */
590 }
591
592 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
593 static void uvco_to_wrapped_pxco(const float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
594 {
595         /* use */
596         *x = fmodf(uv[0], 1.0f);
597         *y = fmodf(uv[1], 1.0f);
598
599         if (*x < 0.0f) *x += 1.0f;
600         if (*y < 0.0f) *y += 1.0f;
601
602         *x = *x * ibuf_x - 0.5f;
603         *y = *y * ibuf_y - 0.5f;
604 }
605
606 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
607 static bool project_paint_PickColor(
608         const ProjPaintState *ps, const float pt[2],
609         float *rgba_fp, unsigned char *rgba, const bool interp)
610 {
611         float w[3], uv[2];
612         int side;
613         int face_index;
614         MTFace *tf;
615         Image *ima;
616         ImBuf *ibuf;
617         int xi, yi;
618
619
620         face_index = project_paint_PickFace(ps, pt, w, &side);
621
622         if (face_index == -1)
623                 return 0;
624
625         tf = *(ps->dm_mtface + face_index);
626
627         if (side == 0) {
628                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[1], tf->uv[2], w);
629         }
630         else { /* QUAD */
631                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[2], tf->uv[3], w);
632         }
633
634         ima = project_paint_face_paint_image(ps, face_index);
635         ibuf = BKE_image_get_first_ibuf(ima); /* we must have got the imbuf before getting here */
636         if (!ibuf) return 0;
637
638         if (interp) {
639                 float x, y;
640                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
641
642                 if (ibuf->rect_float) {
643                         if (rgba_fp) {
644                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
645                         }
646                         else {
647                                 float rgba_tmp_f[4];
648                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
649                                 premul_float_to_straight_uchar(rgba, rgba_tmp_f);
650                         }
651                 }
652                 else {
653                         if (rgba) {
654                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
655                         }
656                         else {
657                                 unsigned char rgba_tmp[4];
658                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
659                                 straight_uchar_to_premul_float(rgba_fp, rgba_tmp);
660                         }
661                 }
662         }
663         else {
664                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
665                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
666                 //if (xi < 0 || xi >= ibuf->x  ||  yi < 0 || yi >= ibuf->y) return 0;
667
668                 /* wrap */
669                 xi = mod_i((int)(uv[0] * ibuf->x), ibuf->x);
670                 yi = mod_i((int)(uv[1] * ibuf->y), ibuf->y);
671
672                 if (rgba) {
673                         if (ibuf->rect_float) {
674                                 const float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
675                                 premul_float_to_straight_uchar(rgba, rgba_tmp_fp);
676                         }
677                         else {
678                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
679                         }
680                 }
681
682                 if (rgba_fp) {
683                         if (ibuf->rect_float) {
684                                 copy_v4_v4(rgba_fp, (ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
685                         }
686                         else {
687                                 unsigned char *tmp_ch = ((unsigned char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
688                                 straight_uchar_to_premul_float(rgba_fp, tmp_ch);
689                         }
690                 }
691         }
692         BKE_image_release_ibuf(ima, ibuf, NULL);
693         return 1;
694 }
695
696 /* Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusuion test)
697  * return...
698  *  0   : no occlusion
699  * -1   : no occlusion but 2D intersection is true (avoid testing the other half of a quad)
700  *  1   : occluded
701  *  2   : occluded with w[3] weights set (need to know in some cases) */
702
703 static int project_paint_occlude_ptv(
704         const float pt[3],
705         const float v1[4], const float v2[4], const float v3[4],
706         float w[3], const bool is_ortho)
707 {
708         /* if all are behind us, return false */
709         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
710                 return 0;
711
712         /* do a 2D point in try intersection */
713         if (!isect_point_tri_v2(pt, v1, v2, v3))
714                 return 0;  /* we know there is  */
715
716
717         /* From here on we know there IS an intersection */
718         /* if ALL of the verts are infront of us then we know it intersects ? */
719         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
720                 return 1;
721         }
722         else {
723                 /* we intersect? - find the exact depth at the point of intersection */
724                 /* Is this point is occluded by another face? */
725                 if (is_ortho) {
726                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
727                 }
728                 else {
729                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
730                 }
731         }
732         return -1;
733 }
734
735
736 static int project_paint_occlude_ptv_clip(
737         const ProjPaintState *ps, const MFace *mf,
738         const float pt[3], const float v1[4], const float v2[4], const float v3[4],
739         const int side)
740 {
741         float w[3], wco[3];
742         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, ps->is_ortho);
743
744         if (ret <= 0)
745                 return ret;
746
747         if (ret == 1) { /* weights not calculated */
748                 if (ps->is_ortho) barycentric_weights_v2(v1, v2, v3, pt, w);
749                 else barycentric_weights_v2_persp(v1, v2, v3, pt, w);
750         }
751
752         /* Test if we're in the clipped area, */
753         if (side) interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v3].co, ps->dm_mvert[mf->v4].co, w);
754         else interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
755
756         if (!ED_view3d_clipping_test(ps->rv3d, wco, true)) {
757                 return 1;
758         }
759
760         return -1;
761 }
762
763
764 /* Check if a screenspace location is occluded by any other faces
765  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
766  * and doesn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
767 static bool project_bucket_point_occluded(
768         const ProjPaintState *ps, LinkNode *bucketFace,
769         const int orig_face, const float pixelScreenCo[4])
770 {
771         MFace *mf;
772         int face_index;
773         int isect_ret;
774         float w[3]; /* not needed when clipping */
775         const bool do_clip = ps->rv3d ? (ps->rv3d->rflag & RV3D_CLIPPING) != 0 : 0;
776
777         /* we could return 0 for 1 face buckets, as long as this function assumes
778          * that the point its testing is only every originated from an existing face */
779
780         for (; bucketFace; bucketFace = bucketFace->next) {
781                 face_index = GET_INT_FROM_POINTER(bucketFace->link);
782
783                 if (orig_face != face_index) {
784                         mf = ps->dm_mface + face_index;
785                         if (do_clip)
786                                 isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], 0);
787                         else
788                                 isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], w, ps->is_ortho);
789
790                         /* Note, if (isect_ret == -1) then we don't want to test the other side of the quad */
791                         if (isect_ret == 0 && mf->v4) {
792                                 if (do_clip)
793                                         isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], 1);
794                                 else
795                                         isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], w, ps->is_ortho);
796                         }
797                         if (isect_ret >= 1) {
798                                 /* TODO - we may want to cache the first hit,
799                                  * it is not possible to swap the face order in the list anymore */
800                                 return true;
801                         }
802                 }
803         }
804         return false;
805 }
806
807 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
808  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
809 #define ISECT_TRUE 1
810 #define ISECT_TRUE_P1 2
811 #define ISECT_TRUE_P2 3
812 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
813 {
814         float y_diff;
815
816         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
817                 *x_isect = p1[0];
818                 return ISECT_TRUE_P1;
819         }
820         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
821                 *x_isect = p2[0];
822                 return ISECT_TRUE_P2;
823         }
824
825         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
826
827         if (y_diff < 0.000001f) {
828                 *x_isect = (p1[0] + p2[0]) * 0.5f;
829                 return ISECT_TRUE;
830         }
831
832         if (p1[1] > y_level && p2[1] < y_level) {
833                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /*(p1[1]-p2[1]);*/
834                 return ISECT_TRUE;
835         }
836         else if (p1[1] < y_level && p2[1] > y_level) {
837                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /*(p2[1]-p1[1]);*/
838                 return ISECT_TRUE;
839         }
840         else {
841                 return 0;
842         }
843 }
844
845 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
846 {
847         float x_diff;
848
849         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
850                 *y_isect = p1[1];
851                 return ISECT_TRUE_P1;
852         }
853         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
854                 *y_isect = p2[1];
855                 return ISECT_TRUE_P2;
856         }
857
858         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
859
860         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
861                 *y_isect = (p1[0] + p2[0]) * 0.5f;
862                 return ISECT_TRUE;
863         }
864
865         if (p1[0] > x_level && p2[0] < x_level) {
866                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff; /*(p1[0]-p2[0]);*/
867                 return ISECT_TRUE;
868         }
869         else if (p1[0] < x_level && p2[0] > x_level) {
870                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff; /*(p2[0]-p1[0]);*/
871                 return ISECT_TRUE;
872         }
873         else {
874                 return 0;
875         }
876 }
877
878 /* simple func use for comparing UV locations to check if there are seams.
879  * Its possible this gives incorrect results, when the UVs for 1 face go into the next
880  * tile, but do not do this for the adjacent face, it could return a false positive.
881  * This is so unlikely that Id not worry about it. */
882 #ifndef PROJ_DEBUG_NOSEAMBLEED
883 static bool cmp_uv(const float vec2a[2], const float vec2b[2])
884 {
885         /* if the UV's are not between 0.0 and 1.0 */
886         float xa = fmodf(vec2a[0], 1.0f);
887         float ya = fmodf(vec2a[1], 1.0f);
888
889         float xb = fmodf(vec2b[0], 1.0f);
890         float yb = fmodf(vec2b[1], 1.0f);
891
892         if (xa < 0.0f) xa += 1.0f;
893         if (ya < 0.0f) ya += 1.0f;
894
895         if (xb < 0.0f) xb += 1.0f;
896         if (yb < 0.0f) yb += 1.0f;
897
898         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
899 }
900 #endif
901
902 /* set min_px and max_px to the image space bounds of the UV coords
903  * return zero if there is no area in the returned rectangle */
904 #ifndef PROJ_DEBUG_NOSEAMBLEED
905 static bool pixel_bounds_uv(
906         const float uv1[2], const float uv2[2], const float uv3[2], const float uv4[2],
907         rcti *bounds_px,
908         const int ibuf_x, const int ibuf_y,
909         const bool is_quad
910         )
911 {
912         float min_uv[2], max_uv[2]; /* UV bounds */
913
914         INIT_MINMAX2(min_uv, max_uv);
915
916         minmax_v2v2_v2(min_uv, max_uv, uv1);
917         minmax_v2v2_v2(min_uv, max_uv, uv2);
918         minmax_v2v2_v2(min_uv, max_uv, uv3);
919         if (is_quad)
920                 minmax_v2v2_v2(min_uv, max_uv, uv4);
921
922         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
923         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
924
925         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
926         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
927
928         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
929
930         /* face uses no UV area when quantized to pixels? */
931         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
932 }
933 #endif
934
935 static bool pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
936 {
937         float min_uv[2], max_uv[2]; /* UV bounds */
938
939         if (tot == 0) {
940                 return 0;
941         }
942
943         INIT_MINMAX2(min_uv, max_uv);
944
945         while (tot--) {
946                 minmax_v2v2_v2(min_uv, max_uv, (*uv));
947                 uv++;
948         }
949
950         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
951         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
952
953         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
954         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
955
956         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
957
958         /* face uses no UV area when quantized to pixels? */
959         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
960 }
961
962 #ifndef PROJ_DEBUG_NOSEAMBLEED
963
964 static void project_face_winding_init(const ProjPaintState *ps, const int face_index)
965 {
966         /* detect the winding of faces in uv space */
967         MTFace *tf = ps->dm_mtface[face_index];
968         float winding = cross_tri_v2(tf->uv[0], tf->uv[1], tf->uv[2]);
969
970         if (ps->dm_mface[face_index].v4)
971                 winding += cross_tri_v2(tf->uv[2], tf->uv[3], tf->uv[0]);
972
973         if (winding > 0)
974                 ps->faceWindingFlags[face_index] |= PROJ_FACE_WINDING_CW;
975
976         ps->faceWindingFlags[face_index] |= PROJ_FACE_WINDING_INIT;
977 }
978
979 /* This function returns 1 if this face has a seam along the 2 face-vert indices
980  * 'orig_i1_fidx' and 'orig_i2_fidx' */
981 static bool check_seam(
982         const ProjPaintState *ps,
983         const int orig_face, const int orig_i1_fidx, const int orig_i2_fidx,
984         int *other_face, int *orig_fidx)
985 {
986         LinkNode *node;
987         int face_index;
988         unsigned int i1, i2;
989         int i1_fidx = -1, i2_fidx = -1; /* index in face */
990         MFace *mf;
991         MTFace *tf;
992         const MFace *orig_mf = ps->dm_mface + orig_face;
993         const MTFace *orig_tf = ps->dm_mtface[orig_face];
994
995         /* vert indices from face vert order indices */
996         i1 = (*(&orig_mf->v1 + orig_i1_fidx));
997         i2 = (*(&orig_mf->v1 + orig_i2_fidx));
998
999         for (node = ps->vertFaces[i1]; node; node = node->next) {
1000                 face_index = GET_INT_FROM_POINTER(node->link);
1001
1002                 if (face_index != orig_face) {
1003                         mf = ps->dm_mface + face_index;
1004                         /* could check if the 2 faces images match here,
1005                          * but then there wouldn't be a way to return the opposite face's info */
1006
1007
1008                         /* We need to know the order of the verts in the adjacent face
1009                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
1010                         i1_fidx = BKE_MESH_TESSFACE_VINDEX_ORDER(mf, i1);
1011                         i2_fidx = BKE_MESH_TESSFACE_VINDEX_ORDER(mf, i2);
1012
1013                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
1014                         if (i2_fidx != -1) {
1015                                 Image *tpage = project_paint_face_paint_image(ps, face_index);
1016                                 Image *orig_tpage = project_paint_face_paint_image(ps, orig_face);
1017
1018                                 BLI_assert(i1_fidx != -1);
1019
1020                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
1021                                 tf = ps->dm_mtface[face_index];
1022
1023                                 /* set up the other face */
1024                                 *other_face = face_index;
1025                                 
1026                                 /* we check if difference is 1 here, else we might have a case of edge 2-0 or 3-0 for quads */
1027                                 *orig_fidx = (i1_fidx < i2_fidx && (i2_fidx - i1_fidx == 1)) ? i1_fidx : i2_fidx;
1028
1029                                 /* initialize face winding if needed */
1030                                 if ((ps->faceWindingFlags[face_index] & PROJ_FACE_WINDING_INIT) == 0)
1031                                         project_face_winding_init(ps, face_index);
1032
1033                                 /* first test if they have the same image */
1034                                 if ((orig_tpage == tpage) &&
1035                                     cmp_uv(orig_tf->uv[orig_i1_fidx], tf->uv[i1_fidx]) &&
1036                                     cmp_uv(orig_tf->uv[orig_i2_fidx], tf->uv[i2_fidx]))
1037                                 {
1038                                         /* if faces don't have the same winding in uv space,
1039                                          * they are on the same side so edge is boundary */
1040                                         if ((ps->faceWindingFlags[face_index] & PROJ_FACE_WINDING_CW) !=
1041                                             (ps->faceWindingFlags[orig_face] & PROJ_FACE_WINDING_CW))
1042                                         {
1043                                                 return 1;
1044                                         }
1045
1046                                         // printf("SEAM (NONE)\n");
1047                                         return 0;
1048
1049                                 }
1050                                 else {
1051                                         // printf("SEAM (UV GAP)\n");
1052                                         return 1;
1053                                 }
1054                         }
1055                 }
1056         }
1057         // printf("SEAM (NO FACE)\n");
1058         *other_face = -1;
1059         return 1;
1060 }
1061
1062 #define SMALL_NUMBER  1.e-6f
1063 BLI_INLINE float shell_v2v2_normal_dir_to_dist(float n[2], float d[2])
1064 {
1065         const float angle_cos = (normalize_v2(n) < SMALL_NUMBER) ? fabsf(dot_v2v2(d, n)) : 0.0f;
1066         return (UNLIKELY(angle_cos < SMALL_NUMBER)) ? 1.0f : (1.0f / angle_cos);
1067 }
1068 #undef SMALL_NUMBER
1069
1070 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
1071  * since the outset coords are a margin that keep an even distance from the original UV's,
1072  * note that the image aspect is taken into account */
1073 static void uv_image_outset(
1074         float (*orig_uv)[2], float (*outset_uv)[2], const float scaler,
1075         const int ibuf_x, const int ibuf_y, const bool is_quad, const bool cw)
1076 {
1077         float a1, a2, a3, a4 = 0.0f;
1078         float puv[4][2]; /* pixelspace uv's */
1079         float no1[2], no2[2], no3[2], no4[2]; /* normals */
1080         float dir1[2], dir2[2], dir3[2], dir4[2];
1081         float ibuf_inv[2];
1082
1083         ibuf_inv[0] = 1.0f / (float)ibuf_x;
1084         ibuf_inv[1] = 1.0f / (float)ibuf_y;
1085
1086         /* make UV's in pixel space so we can */
1087         puv[0][0] = orig_uv[0][0] * ibuf_x;
1088         puv[0][1] = orig_uv[0][1] * ibuf_y;
1089
1090         puv[1][0] = orig_uv[1][0] * ibuf_x;
1091         puv[1][1] = orig_uv[1][1] * ibuf_y;
1092
1093         puv[2][0] = orig_uv[2][0] * ibuf_x;
1094         puv[2][1] = orig_uv[2][1] * ibuf_y;
1095
1096         if (is_quad) {
1097                 puv[3][0] = orig_uv[3][0] * ibuf_x;
1098                 puv[3][1] = orig_uv[3][1] * ibuf_y;
1099         }
1100
1101         /* face edge directions */
1102         sub_v2_v2v2(dir1, puv[1], puv[0]);
1103         sub_v2_v2v2(dir2, puv[2], puv[1]);
1104         normalize_v2(dir1);
1105         normalize_v2(dir2);
1106
1107         if (is_quad) {
1108                 sub_v2_v2v2(dir3, puv[3], puv[2]);
1109                 sub_v2_v2v2(dir4, puv[0], puv[3]);
1110                 normalize_v2(dir3);
1111                 normalize_v2(dir4);
1112         }
1113         else {
1114                 sub_v2_v2v2(dir3, puv[0], puv[2]);
1115                 normalize_v2(dir3);
1116         }
1117
1118         if (is_quad) {
1119                 /* here we just use the orthonormality property (a1, a2) dot (a2, -a1) = 0
1120                  * to get normals from the edge directions based on the winding */
1121                 if (cw) {
1122                         no1[0] = -dir4[1] - dir1[1];
1123                         no1[1] = dir4[0] + dir1[0];
1124                         no2[0] = -dir1[1] - dir2[1];
1125                         no2[1] = dir1[0] + dir2[0];
1126                         no3[0] = -dir2[1] - dir3[1];
1127                         no3[1] = dir2[0] + dir3[0];
1128                         no4[0] = -dir3[1] - dir4[1];
1129                         no4[1] = dir3[0] + dir4[0];
1130                 }
1131                 else {
1132                         no1[0] = dir4[1] + dir1[1];
1133                         no1[1] = -dir4[0] - dir1[0];
1134                         no2[0] = dir1[1] + dir2[1];
1135                         no2[1] = -dir1[0] - dir2[0];
1136                         no3[0] = dir2[1] + dir3[1];
1137                         no3[1] = -dir2[0] - dir3[0];
1138                         no4[0] = dir3[1] + dir4[1];
1139                         no4[1] = -dir3[0] - dir4[0];
1140                 }
1141
1142                 a1 = shell_v2v2_normal_dir_to_dist(no1, dir4);
1143                 a2 = shell_v2v2_normal_dir_to_dist(no2, dir1);
1144                 a3 = shell_v2v2_normal_dir_to_dist(no3, dir2);
1145                 a4 = shell_v2v2_normal_dir_to_dist(no4, dir3);
1146
1147                 mul_v2_fl(no1, a1 * scaler);
1148                 mul_v2_fl(no2, a2 * scaler);
1149                 mul_v2_fl(no3, a3 * scaler);
1150                 mul_v2_fl(no4, a4 * scaler);
1151                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1152                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1153                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1154                 add_v2_v2v2(outset_uv[3], puv[3], no4);
1155                 mul_v2_v2(outset_uv[0], ibuf_inv);
1156                 mul_v2_v2(outset_uv[1], ibuf_inv);
1157                 mul_v2_v2(outset_uv[2], ibuf_inv);
1158                 mul_v2_v2(outset_uv[3], ibuf_inv);
1159         }
1160         else {
1161                 if (cw) {
1162                         no1[0] = -dir3[1] - dir1[1];
1163                         no1[1] = dir3[0] + dir1[0];
1164                         no2[0] = -dir1[1] - dir2[1];
1165                         no2[1] = dir1[0] + dir2[0];
1166                         no3[0] = -dir2[1] - dir3[1];
1167                         no3[1] = dir2[0] + dir3[0];
1168                 }
1169                 else {
1170                         no1[0] = dir3[1] + dir1[1];
1171                         no1[1] = -dir3[0] - dir1[0];
1172                         no2[0] = dir1[1] + dir2[1];
1173                         no2[1] = -dir1[0] - dir2[0];
1174                         no3[0] = dir2[1] + dir3[1];
1175                         no3[1] = -dir2[0] - dir3[0];
1176                 }
1177
1178                 a1 = shell_v2v2_normal_dir_to_dist(no1, dir3);
1179                 a2 = shell_v2v2_normal_dir_to_dist(no2, dir1);
1180                 a3 = shell_v2v2_normal_dir_to_dist(no3, dir2);
1181
1182                 mul_v2_fl(no1, a1 * scaler);
1183                 mul_v2_fl(no2, a2 * scaler);
1184                 mul_v2_fl(no3, a3 * scaler);
1185                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1186                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1187                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1188
1189                 mul_v2_v2(outset_uv[0], ibuf_inv);
1190                 mul_v2_v2(outset_uv[1], ibuf_inv);
1191                 mul_v2_v2(outset_uv[2], ibuf_inv);
1192         }
1193 }
1194
1195 /*
1196  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1197  * 1<<i - where i is (0-3)
1198  *
1199  * If we're multithreadng, make sure threads are locked when this is called
1200  */
1201 static void project_face_seams_init(const ProjPaintState *ps, const int face_index, const int is_quad)
1202 {
1203         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1204         int fidx1 = is_quad ? 3 : 2;
1205         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 */
1206
1207         /* initialize face winding if needed */
1208         if ((ps->faceWindingFlags[face_index] & PROJ_FACE_WINDING_INIT) == 0)
1209                 project_face_winding_init(ps, face_index);
1210
1211         do {
1212                 if ((ps->faceSeamFlags[face_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1213                         if (check_seam(ps, face_index, fidx1, fidx2, &other_face, &other_fidx)) {
1214                                 ps->faceSeamFlags[face_index] |= 1 << fidx1;
1215                                 if (other_face != -1)
1216                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1217                         }
1218                         else {
1219                                 ps->faceSeamFlags[face_index] |= 16 << fidx1;
1220                                 if (other_face != -1)
1221                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1222                         }
1223                 }
1224
1225                 fidx2 = fidx1;
1226         } while (fidx1--);
1227 }
1228 #endif // PROJ_DEBUG_NOSEAMBLEED
1229
1230
1231 /* Converts a UV location to a 3D screenspace location
1232  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1233  *
1234  * This is used for finding a pixels location in screenspace for painting */
1235 static void screen_px_from_ortho(
1236         const float uv[2],
1237         const float v1co[3], const float v2co[3], const float v3co[3],  /* Screenspace coords */
1238         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1239         float pixelScreenCo[4],
1240         float w[3])
1241 {
1242         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1243         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1244 }
1245
1246 /* same as screen_px_from_ortho except we
1247  * do perspective correction on the pixel coordinate */
1248 static void screen_px_from_persp(
1249         const float uv[2],
1250         const float v1co[4], const float v2co[4], const float v3co[4],  /* screenspace coords */
1251         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1252         float pixelScreenCo[4],
1253         float w[3])
1254 {
1255         float w_int[3];
1256         float wtot_inv, wtot;
1257         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1258
1259         /* re-weight from the 4th coord of each screen vert */
1260         w_int[0] = w[0] * v1co[3];
1261         w_int[1] = w[1] * v2co[3];
1262         w_int[2] = w[2] * v3co[3];
1263
1264         wtot = w_int[0] + w_int[1] + w_int[2];
1265
1266         if (wtot > 0.0f) {
1267                 wtot_inv = 1.0f / wtot;
1268                 w_int[0] *= wtot_inv;
1269                 w_int[1] *= wtot_inv;
1270                 w_int[2] *= wtot_inv;
1271         }
1272         else {
1273                 w[0] = w[1] = w[2] =
1274                 w_int[0] = w_int[1] = w_int[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1275         }
1276         /* done re-weighting */
1277
1278         /* do interpolation based on projected weight */
1279         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w_int);
1280 }
1281
1282
1283 static void project_face_pixel(
1284         const MTFace *tf_other, ImBuf *ibuf_other, const float w[3],
1285         bool side, unsigned char rgba_ub[4], float rgba_f[4])
1286 {
1287         const float *uvCo1, *uvCo2, *uvCo3;
1288         float uv_other[2], x, y;
1289
1290         uvCo1 =  tf_other->uv[0];
1291         if (side == 1) {
1292                 uvCo2 = tf_other->uv[2];
1293                 uvCo3 = tf_other->uv[3];
1294         }
1295         else {
1296                 uvCo2 =  tf_other->uv[1];
1297                 uvCo3 =  tf_other->uv[2];
1298         }
1299
1300         interp_v2_v2v2v2(uv_other, uvCo1, uvCo2, uvCo3, w);
1301
1302         /* use */
1303         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1304
1305
1306         if (ibuf_other->rect_float) { /* from float to float */
1307                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1308         }
1309         else { /* from char to float */
1310                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1311         }
1312
1313 }
1314
1315 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1316 static float project_paint_uvpixel_mask(
1317         const ProjPaintState *ps,
1318         const int face_index,
1319         const bool side,
1320         const float w[3])
1321 {
1322         float mask;
1323
1324         /* Image Mask */
1325         if (ps->do_layer_stencil) {
1326                 /* another UV maps image is masking this one's */
1327                 ImBuf *ibuf_other;
1328                 Image *other_tpage = ps->stencil_ima;
1329                 const MTFace *tf_other = ps->dm_mtface_stencil + face_index;
1330
1331                 if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1332                         /* BKE_image_acquire_ibuf - TODO - this may be slow */
1333                         unsigned char rgba_ub[4];
1334                         float rgba_f[4];
1335
1336                         project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, rgba_f);
1337
1338                         if (ibuf_other->rect_float) { /* from float to float */
1339                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) * (1.0f / 3.0f)) * rgba_f[3];
1340                         }
1341                         else { /* from char to float */
1342                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) * (1.0f / (255.0f * 3.0f))) * (rgba_ub[3] * (1.0f / 255.0f));
1343                         }
1344
1345                         BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1346
1347                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1348                                 mask = (1.0f - mask);
1349
1350                         if (mask == 0.0f) {
1351                                 return 0.0f;
1352                         }
1353                 }
1354                 else {
1355                         return 0.0f;
1356                 }
1357         }
1358         else {
1359                 mask = 1.0f;
1360         }
1361
1362         if (ps->do_mask_cavity) {
1363                 MFace *mf = &ps->dm_mface[face_index];
1364                 float ca1, ca2, ca3, ca_mask;
1365                 ca1 = ps->cavities[mf->v1];
1366                 if (side == 1) {
1367                         ca2 = ps->cavities[mf->v3];
1368                         ca3 = ps->cavities[mf->v4];
1369                 }
1370                 else {
1371                         ca2 = ps->cavities[mf->v2];
1372                         ca3 = ps->cavities[mf->v3];
1373                 }
1374
1375                 ca_mask = w[0] * ca1 + w[1] * ca2 + w[2] * ca3;
1376                 ca_mask = curvemapping_evaluateF(ps->cavity_curve, 0, ca_mask);
1377                 CLAMP(ca_mask, 0.0f, 1.0f);
1378                 mask *= ca_mask;
1379         }
1380
1381         /* calculate mask */
1382         if (ps->do_mask_normal) {
1383                 MFace *mf = &ps->dm_mface[face_index];
1384                 float no[3], angle_cos;
1385                 if (mf->flag & ME_SMOOTH) {
1386                         const short *no1, *no2, *no3;
1387                         no1 = ps->dm_mvert[mf->v1].no;
1388                         if (side == 1) {
1389                                 no2 = ps->dm_mvert[mf->v3].no;
1390                                 no3 = ps->dm_mvert[mf->v4].no;
1391                         }
1392                         else {
1393                                 no2 = ps->dm_mvert[mf->v2].no;
1394                                 no3 = ps->dm_mvert[mf->v3].no;
1395                         }
1396
1397                         no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1398                         no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1399                         no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1400                         normalize_v3(no);
1401                 }
1402                 else {
1403                         /* incase the */
1404 #if 1
1405                         /* normalizing per pixel isn't optimal, we could cache or check ps->*/
1406                         if (mf->v4)
1407                                 normal_quad_v3(no,
1408                                                ps->dm_mvert[mf->v1].co,
1409                                                ps->dm_mvert[mf->v2].co,
1410                                                ps->dm_mvert[mf->v3].co,
1411                                                ps->dm_mvert[mf->v4].co);
1412                         else
1413                                 normal_tri_v3(no,
1414                                               ps->dm_mvert[mf->v1].co,
1415                                               ps->dm_mvert[mf->v2].co,
1416                                               ps->dm_mvert[mf->v3].co);
1417 #else
1418                         /* don't use because some modifiers dont have normal data (subsurf for eg) */
1419                         copy_v3_v3(no, (float *)ps->dm->getTessFaceData(ps->dm, face_index, CD_NORMAL));
1420 #endif
1421                 }
1422
1423                 if (UNLIKELY(ps->is_flip_object)) {
1424                         negate_v3(no);
1425                 }
1426
1427                 /* now we can use the normal as a mask */
1428                 if (ps->is_ortho) {
1429                         angle_cos = dot_v3v3(ps->viewDir, no);
1430                 }
1431                 else {
1432                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1433                         float viewDirPersp[3];
1434                         const float *co1, *co2, *co3;
1435                         co1 = ps->dm_mvert[mf->v1].co;
1436                         if (side == 1) {
1437                                 co2 = ps->dm_mvert[mf->v3].co;
1438                                 co3 = ps->dm_mvert[mf->v4].co;
1439                         }
1440                         else {
1441                                 co2 = ps->dm_mvert[mf->v2].co;
1442                                 co3 = ps->dm_mvert[mf->v3].co;
1443                         }
1444
1445                         /* Get the direction from the viewPoint to the pixel and normalize */
1446                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1447                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1448                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1449                         normalize_v3(viewDirPersp);
1450                         if (UNLIKELY(ps->is_flip_object)) {
1451                                 negate_v3(viewDirPersp);
1452                         }
1453
1454                         angle_cos = dot_v3v3(viewDirPersp, no);
1455                 }
1456
1457                 if (angle_cos <= ps->normal_angle__cos) {
1458                         return 0.0f; /* outsize the normal limit*/
1459                 }
1460                 else if (angle_cos < ps->normal_angle_inner__cos) {
1461                         mask *= (ps->normal_angle - acosf(angle_cos)) / ps->normal_angle_range;
1462                 } /* otherwise no mask normal is needed, were within the limit */
1463         }
1464
1465         /* This only works when the opacity dosnt change while painting, stylus pressure messes with this
1466          * so don't use it. */
1467         // if (ps->is_airbrush == 0) mask *= BKE_brush_alpha_get(ps->brush);
1468
1469         return mask;
1470 }
1471
1472 static int project_paint_pixel_sizeof(const short tool)
1473 {
1474         if ((tool == PAINT_TOOL_CLONE) || (tool == PAINT_TOOL_SMEAR)) {
1475                 return sizeof(ProjPixelClone);
1476         }
1477         else {
1478                 return sizeof(ProjPixel);
1479         }
1480 }
1481
1482 static int project_paint_undo_subtiles(const TileInfo *tinf, int tx, int ty)
1483 {
1484         ProjPaintImage *pjIma = tinf->pjima;
1485         int tile_index = tx + ty * tinf->tile_width;
1486         bool generate_tile = false;
1487
1488         /* double check lock to avoid locking */
1489         if (UNLIKELY(!pjIma->undoRect[tile_index])) {
1490                 if (tinf->lock)
1491                         BLI_spin_lock(tinf->lock);
1492                 if (LIKELY(!pjIma->undoRect[tile_index])) {
1493                         pjIma->undoRect[tile_index] = TILE_PENDING;
1494                         generate_tile = true;
1495                 }
1496                 if (tinf->lock)
1497                         BLI_spin_unlock(tinf->lock);
1498         }
1499
1500
1501         if (generate_tile) {
1502                 volatile void *undorect;
1503                 if (tinf->masked) {
1504                         undorect = image_undo_push_tile(pjIma->ima, pjIma->ibuf, tinf->tmpibuf, tx, ty, &pjIma->maskRect[tile_index], &pjIma->valid[tile_index], true);
1505                 }
1506                 else {
1507                         undorect = image_undo_push_tile(pjIma->ima, pjIma->ibuf, tinf->tmpibuf, tx, ty, NULL, &pjIma->valid[tile_index], true);
1508                 }
1509
1510                 pjIma->ibuf->userflags |= IB_BITMAPDIRTY;
1511                 /* tile ready, publish */
1512                 if (tinf->lock)
1513                         BLI_spin_lock(tinf->lock);
1514                 pjIma->undoRect[tile_index] = undorect;
1515                 if (tinf->lock)
1516                         BLI_spin_unlock(tinf->lock);
1517
1518         }
1519
1520         return tile_index;
1521 }
1522
1523 /* run this function when we know a bucket's, face's pixel can be initialized,
1524  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1525 static ProjPixel *project_paint_uvpixel_init(
1526         const ProjPaintState *ps,
1527         MemArena *arena,
1528         const TileInfo *tinf,
1529         int x_px, int y_px,
1530         const float mask,
1531         const int face_index,
1532         const float pixelScreenCo[4],
1533         const float world_spaceCo[3],
1534         const bool side,
1535         const float w[3])
1536 {
1537         ProjPixel *projPixel;
1538         int x_tile, y_tile;
1539         int x_round, y_round;
1540         int tile_offset;
1541         /* volatile is important here to ensure pending check is not optimized away by compiler*/
1542         volatile int tile_index;
1543
1544         ProjPaintImage *projima = tinf->pjima;
1545         ImBuf *ibuf = projima->ibuf;
1546         /* wrap pixel location */
1547
1548         x_px = mod_i(x_px, ibuf->x);
1549         y_px = mod_i(y_px, ibuf->y);
1550
1551         BLI_assert(ps->pixel_sizeof == project_paint_pixel_sizeof(ps->tool));
1552         projPixel = BLI_memarena_alloc(arena, ps->pixel_sizeof);
1553
1554         /* calculate the undo tile offset of the pixel, used to store the original
1555          * pixel color and accumulated mask if any */
1556         x_tile =  x_px >> IMAPAINT_TILE_BITS;
1557         y_tile =  y_px >> IMAPAINT_TILE_BITS;
1558
1559         x_round = x_tile * IMAPAINT_TILE_SIZE;
1560         y_round = y_tile * IMAPAINT_TILE_SIZE;
1561         //memset(projPixel, 0, size);
1562
1563         tile_offset = (x_px - x_round) + (y_px - y_round) * IMAPAINT_TILE_SIZE;
1564         tile_index = project_paint_undo_subtiles(tinf, x_tile, y_tile);
1565
1566         /* other thread may be initializing the tile so wait here */
1567         while (projima->undoRect[tile_index] == TILE_PENDING)
1568                 ;
1569
1570         BLI_assert(tile_index < (IMAPAINT_TILE_NUMBER(ibuf->x) * IMAPAINT_TILE_NUMBER(ibuf->y)));
1571         BLI_assert(tile_offset < (IMAPAINT_TILE_SIZE * IMAPAINT_TILE_SIZE));
1572
1573         projPixel->valid = projima->valid[tile_index];
1574
1575         if (ibuf->rect_float) {
1576                 projPixel->pixel.f_pt = ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1577                 projPixel->origColor.f_pt = (float *)projima->undoRect[tile_index] + 4 * tile_offset;
1578                 zero_v4(projPixel->newColor.f);
1579         }
1580         else {
1581                 projPixel->pixel.ch_pt = (unsigned char *)(ibuf->rect + (x_px + y_px * ibuf->x));
1582                 projPixel->origColor.uint_pt = (unsigned int *)projima->undoRect[tile_index] + tile_offset;
1583                 projPixel->newColor.uint = 0;
1584         }
1585
1586         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1587         if (ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D) {
1588                 copy_v3_v3(projPixel->worldCoSS, world_spaceCo);
1589         }
1590
1591         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1592
1593         projPixel->x_px = x_px;
1594         projPixel->y_px = y_px;
1595
1596         projPixel->mask = (unsigned short)(mask * 65535);
1597         if (ps->do_masking)
1598                 projPixel->mask_accum = projima->maskRect[tile_index] + tile_offset;
1599         else
1600                 projPixel->mask_accum = NULL;
1601
1602         /* which bounding box cell are we in?, needed for undo */
1603         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1604                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1605
1606         /* done with view3d_project_float inline */
1607         if (ps->tool == PAINT_TOOL_CLONE) {
1608                 if (ps->dm_mtface_clone) {
1609                         ImBuf *ibuf_other;
1610                         Image *other_tpage = project_paint_face_clone_image(ps, face_index);
1611                         const MTFace *tf_other = ps->dm_mtface_clone[face_index];
1612
1613                         if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1614                                 /* BKE_image_acquire_ibuf - TODO - this may be slow */
1615
1616                                 if (ibuf->rect_float) {
1617                                         if (ibuf_other->rect_float) { /* from float to float */
1618                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1619                                         }
1620                                         else { /* from char to float */
1621                                                 unsigned char rgba_ub[4];
1622                                                 float rgba[4];
1623                                                 project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, NULL);
1624                                                 srgb_to_linearrgb_uchar4(rgba, rgba_ub);
1625                                                 straight_to_premul_v4_v4(((ProjPixelClone *)projPixel)->clonepx.f, rgba);
1626                                         }
1627                                 }
1628                                 else {
1629                                         if (ibuf_other->rect_float) { /* float to char */
1630                                                 float rgba[4];
1631                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, rgba);
1632                                                 premul_to_straight_v4(rgba);
1633                                                 linearrgb_to_srgb_uchar3(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1634                                                 ((ProjPixelClone *)projPixel)->clonepx.ch[3] =  rgba[3] * 255;
1635                                         }
1636                                         else { /* char to char */
1637                                                 project_face_pixel(tf_other, ibuf_other, w, side, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1638                                         }
1639                                 }
1640
1641                                 BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1642                         }
1643                         else {
1644                                 if (ibuf->rect_float) {
1645                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1646                                 }
1647                                 else {
1648                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1649                                 }
1650                         }
1651
1652                 }
1653                 else {
1654                         float co[2];
1655                         sub_v2_v2v2(co, projPixel->projCoSS, ps->cloneOffset);
1656
1657                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1658                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1659                         if (ibuf->rect_float) {
1660                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1661                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1662                                 }
1663                         }
1664                         else {
1665                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1666                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1667                                 }
1668                         }
1669                 }
1670         }
1671
1672 #ifdef PROJ_DEBUG_PAINT
1673         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1674         else                  projPixel->pixel.ch_pt[0] = 0;
1675 #endif
1676         /* pointer arithmetics */
1677         projPixel->image_index = projima - ps->projImages;
1678
1679         return projPixel;
1680 }
1681
1682 static bool line_clip_rect2f(
1683         const rctf *rect,
1684         const float l1[2], const float l2[2],
1685         float l1_clip[2], float l2_clip[2])
1686 {
1687         /* first account for horizontal, then vertical lines */
1688         /* horiz */
1689         if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) {
1690                 /* is the line out of range on its Y axis? */
1691                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1692                         return 0;
1693                 }
1694                 /* line is out of range on its X axis */
1695                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1696                         return 0;
1697                 }
1698
1699
1700                 if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1701                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1702                                 copy_v2_v2(l1_clip, l1);
1703                                 copy_v2_v2(l2_clip, l2);
1704                                 return 1;
1705                         }
1706                         else {
1707                                 return 0;
1708                         }
1709                 }
1710
1711                 copy_v2_v2(l1_clip, l1);
1712                 copy_v2_v2(l2_clip, l2);
1713                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1714                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1715                 return 1;
1716         }
1717         else if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) {
1718                 /* is the line out of range on its X axis? */
1719                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1720                         return 0;
1721                 }
1722
1723                 /* line is out of range on its Y axis */
1724                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1725                         return 0;
1726                 }
1727
1728                 if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1729                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1730                                 copy_v2_v2(l1_clip, l1);
1731                                 copy_v2_v2(l2_clip, l2);
1732                                 return 1;
1733                         }
1734                         else {
1735                                 return 0;
1736                         }
1737                 }
1738
1739                 copy_v2_v2(l1_clip, l1);
1740                 copy_v2_v2(l2_clip, l2);
1741                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1742                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1743                 return 1;
1744         }
1745         else {
1746                 float isect;
1747                 short ok1 = 0;
1748                 short ok2 = 0;
1749
1750                 /* Done with vertical lines */
1751
1752                 /* are either of the points inside the rectangle ? */
1753                 if (BLI_rctf_isect_pt_v(rect, l1)) {
1754                         copy_v2_v2(l1_clip, l1);
1755                         ok1 = 1;
1756                 }
1757
1758                 if (BLI_rctf_isect_pt_v(rect, l2)) {
1759                         copy_v2_v2(l2_clip, l2);
1760                         ok2 = 1;
1761                 }
1762
1763                 /* line inside rect */
1764                 if (ok1 && ok2) return 1;
1765
1766                 /* top/bottom */
1767                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1768                         if (l1[1] < l2[1]) { /* line 1 is outside */
1769                                 l1_clip[0] = isect;
1770                                 l1_clip[1] = rect->ymin;
1771                                 ok1 = 1;
1772                         }
1773                         else {
1774                                 l2_clip[0] = isect;
1775                                 l2_clip[1] = rect->ymin;
1776                                 ok2 = 2;
1777                         }
1778                 }
1779
1780                 if (ok1 && ok2) return 1;
1781
1782                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1783                         if (l1[1] > l2[1]) { /* line 1 is outside */
1784                                 l1_clip[0] = isect;
1785                                 l1_clip[1] = rect->ymax;
1786                                 ok1 = 1;
1787                         }
1788                         else {
1789                                 l2_clip[0] = isect;
1790                                 l2_clip[1] = rect->ymax;
1791                                 ok2 = 2;
1792                         }
1793                 }
1794
1795                 if (ok1 && ok2) return 1;
1796
1797                 /* left/right */
1798                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1799                         if (l1[0] < l2[0]) { /* line 1 is outside */
1800                                 l1_clip[0] = rect->xmin;
1801                                 l1_clip[1] = isect;
1802                                 ok1 = 1;
1803                         }
1804                         else {
1805                                 l2_clip[0] = rect->xmin;
1806                                 l2_clip[1] = isect;
1807                                 ok2 = 2;
1808                         }
1809                 }
1810
1811                 if (ok1 && ok2) return 1;
1812
1813                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1814                         if (l1[0] > l2[0]) { /* line 1 is outside */
1815                                 l1_clip[0] = rect->xmax;
1816                                 l1_clip[1] = isect;
1817                                 ok1 = 1;
1818                         }
1819                         else {
1820                                 l2_clip[0] = rect->xmax;
1821                                 l2_clip[1] = isect;
1822                                 ok2 = 2;
1823                         }
1824                 }
1825
1826                 if (ok1 && ok2) {
1827                         return 1;
1828                 }
1829                 else {
1830                         return 0;
1831                 }
1832         }
1833 }
1834
1835
1836
1837 /* scale the quad & tri about its center
1838  * scaling by PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1839  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces */
1840 #ifndef PROJ_DEBUG_NOSEAMBLEED
1841 static void scale_quad(float insetCos[4][3], float *origCos[4], const float inset)
1842 {
1843         float cent[3];
1844         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0] + origCos[3][0]) * (1.0f / 4.0f);
1845         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1] + origCos[3][1]) * (1.0f / 4.0f);
1846         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2] + origCos[3][2]) * (1.0f / 4.0f);
1847
1848         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1849         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1850         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1851         sub_v3_v3v3(insetCos[3], origCos[3], cent);
1852
1853         mul_v3_fl(insetCos[0], inset);
1854         mul_v3_fl(insetCos[1], inset);
1855         mul_v3_fl(insetCos[2], inset);
1856         mul_v3_fl(insetCos[3], inset);
1857
1858         add_v3_v3(insetCos[0], cent);
1859         add_v3_v3(insetCos[1], cent);
1860         add_v3_v3(insetCos[2], cent);
1861         add_v3_v3(insetCos[3], cent);
1862 }
1863
1864
1865 static void scale_tri(float insetCos[4][3], float *origCos[4], const float inset)
1866 {
1867         float cent[3];
1868         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) * (1.0f / 3.0f);
1869         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) * (1.0f / 3.0f);
1870         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) * (1.0f / 3.0f);
1871
1872         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1873         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1874         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1875
1876         mul_v3_fl(insetCos[0], inset);
1877         mul_v3_fl(insetCos[1], inset);
1878         mul_v3_fl(insetCos[2], inset);
1879
1880         add_v3_v3(insetCos[0], cent);
1881         add_v3_v3(insetCos[1], cent);
1882         add_v3_v3(insetCos[2], cent);
1883 }
1884 #endif //PROJ_DEBUG_NOSEAMBLEED
1885
1886 static float len_squared_v2v2_alt(const float v1[2], const float v2_1, const float v2_2)
1887 {
1888         float x, y;
1889
1890         x = v1[0] - v2_1;
1891         y = v1[1] - v2_2;
1892         return x * x + y * y;
1893 }
1894
1895 /* note, use a squared value so we can use len_squared_v2v2
1896  * be sure that you have done a bounds check first or this may fail */
1897 /* only give bucket_bounds as an arg because we need it elsewhere */
1898 static bool project_bucket_isect_circle(const float cent[2], const float radius_squared, const rctf *bucket_bounds)
1899 {
1900
1901         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect
1902          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1903          * this is even less work then an intersection test
1904          */
1905 #if 0
1906         if (BLI_rctf_isect_pt_v(bucket_bounds, cent))
1907                 return 1;
1908 #endif
1909
1910         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1911             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1912         {
1913                 return 1;
1914         }
1915
1916         /* out of bounds left */
1917         if (cent[0] < bucket_bounds->xmin) {
1918                 /* lower left out of radius test */
1919                 if (cent[1] < bucket_bounds->ymin) {
1920                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1921                 }
1922                 /* top left test */
1923                 else if (cent[1] > bucket_bounds->ymax) {
1924                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1925                 }
1926         }
1927         else if (cent[0] > bucket_bounds->xmax) {
1928                 /* lower right out of radius test */
1929                 if (cent[1] < bucket_bounds->ymin) {
1930                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1931                 }
1932                 /* top right test */
1933                 else if (cent[1] > bucket_bounds->ymax) {
1934                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1935                 }
1936         }
1937
1938         return 0;
1939 }
1940
1941
1942
1943 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1944  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1945  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1946  * (viewed from the side)
1947  *
1948  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1949  * funcs that only account for points inside the triangle.
1950  * however switching back to this for ortho is always an option */
1951
1952 static void rect_to_uvspace_ortho(
1953         const rctf *bucket_bounds,
1954         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1955         const float *uv1co, const float *uv2co, const float *uv3co,
1956         float bucket_bounds_uv[4][2],
1957         const int flip)
1958 {
1959         float uv[2];
1960         float w[3];
1961
1962         /* get the UV space bounding box */
1963         uv[0] = bucket_bounds->xmax;
1964         uv[1] = bucket_bounds->ymin;
1965         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1966         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1967
1968         //uv[0] = bucket_bounds->xmax; // set above
1969         uv[1] = bucket_bounds->ymax;
1970         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1971         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1972
1973         uv[0] = bucket_bounds->xmin;
1974         //uv[1] = bucket_bounds->ymax; // set above
1975         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1976         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1977
1978         //uv[0] = bucket_bounds->xmin; // set above
1979         uv[1] = bucket_bounds->ymin;
1980         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1981         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1982 }
1983
1984 /* same as above but use barycentric_weights_v2_persp */
1985 static void rect_to_uvspace_persp(
1986         const rctf *bucket_bounds,
1987         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1988         const float *uv1co, const float *uv2co, const float *uv3co,
1989         float bucket_bounds_uv[4][2],
1990         const int flip
1991         )
1992 {
1993         float uv[2];
1994         float w[3];
1995
1996         /* get the UV space bounding box */
1997         uv[0] = bucket_bounds->xmax;
1998         uv[1] = bucket_bounds->ymin;
1999         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2000         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
2001
2002         //uv[0] = bucket_bounds->xmax; // set above
2003         uv[1] = bucket_bounds->ymax;
2004         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2005         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
2006
2007         uv[0] = bucket_bounds->xmin;
2008         //uv[1] = bucket_bounds->ymax; // set above
2009         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2010         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
2011
2012         //uv[0] = bucket_bounds->xmin; // set above
2013         uv[1] = bucket_bounds->ymin;
2014         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
2015         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
2016 }
2017
2018 /* This works as we need it to but we can save a few steps and not use it */
2019
2020 #if 0
2021 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
2022 {
2023         float v1[2], v2[2];
2024
2025         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
2026         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
2027
2028         return -atan2f(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
2029 }
2030 #endif
2031
2032 #define ISECT_1 (1)
2033 #define ISECT_2 (1 << 1)
2034 #define ISECT_3 (1 << 2)
2035 #define ISECT_4 (1 << 3)
2036 #define ISECT_ALL3 ((1 << 3) - 1)
2037 #define ISECT_ALL4 ((1 << 4) - 1)
2038
2039 /* limit must be a fraction over 1.0f */
2040 static bool IsectPT2Df_limit(
2041         const float pt[2],
2042         const float v1[2], const float v2[2], const float v3[2],
2043         const float limit)
2044 {
2045         return ((area_tri_v2(pt, v1, v2) +
2046                  area_tri_v2(pt, v2, v3) +
2047                  area_tri_v2(pt, v3, v1)) / (area_tri_v2(v1, v2, v3))) < limit;
2048 }
2049
2050 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
2051  * so we have the clipped UV's to do pixel intersection tests with
2052  * */
2053 static int float_z_sort_flip(const void *p1, const void *p2)
2054 {
2055         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
2056 }
2057
2058 static int float_z_sort(const void *p1, const void *p2)
2059 {
2060         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
2061 }
2062
2063 /* assumes one point is within the rectangle */
2064 static bool line_rect_clip(
2065         const rctf *rect,
2066         const float l1[4], const float l2[4],
2067         const float uv1[2], const float uv2[2],
2068         float uv[2], bool is_ortho)
2069 {
2070         float min = FLT_MAX, tmp;
2071         float xlen = l2[0] - l1[0];
2072         float ylen = l2[1] - l1[1];
2073
2074         /* 0.1 might seem too much, but remember, this is pixels! */
2075         if (xlen > 0.1f) {
2076                 if ((l1[0] - rect->xmin) * (l2[0] - rect->xmin) <= 0) {
2077                         tmp = rect->xmin;
2078                         min = min_ff((tmp - l1[0]) / xlen, min);
2079                 }
2080                 else if ((l1[0] - rect->xmax) * (l2[0] - rect->xmax) < 0) {
2081                         tmp = rect->xmax;
2082                         min = min_ff((tmp - l1[0]) / xlen, min);
2083                 }
2084         }
2085
2086         if (ylen > 0.1f) {
2087                 if ((l1[1] - rect->ymin) * (l2[1] - rect->ymin) <= 0) {
2088                         tmp = rect->ymin;
2089                         min = min_ff((tmp - l1[1]) / ylen, min);
2090                 }
2091                 else if ((l1[1] - rect->ymax) * (l2[1] - rect->ymax) < 0) {
2092                         tmp = rect->ymax;
2093                         min = min_ff((tmp - l1[1]) / ylen, min);
2094                 }
2095         }
2096
2097         if (min == FLT_MAX)
2098                 return false;
2099
2100         tmp = (is_ortho) ? 1.0f : (l1[3] + min * (l2[3] - l1[3]));
2101
2102         uv[0] = (uv1[0] + min / tmp * (uv2[0] - uv1[0]));
2103         uv[1] = (uv1[1] + min / tmp * (uv2[1] - uv1[1]));
2104
2105         return true;
2106 }
2107
2108
2109 static void project_bucket_clip_face(
2110         const bool is_ortho, const bool is_flip_object,
2111         const rctf *bucket_bounds,
2112         const float *v1coSS, const float *v2coSS, const float *v3coSS,
2113         const float *uv1co, const float *uv2co, const float *uv3co,
2114         float bucket_bounds_uv[8][2],
2115         int *tot, bool cull)
2116 {
2117         int inside_bucket_flag = 0;
2118         int inside_face_flag = 0;
2119         int flip;
2120         bool colinear = false;
2121         
2122         float bucket_bounds_ss[4][2];
2123
2124         /* detect pathological case where face the three vertices are almost colinear in screen space.
2125          * mostly those will be culled but when flood filling or with smooth shading it's a possibility */
2126         if (dist_squared_to_line_v2(v1coSS, v2coSS, v3coSS) < 0.5f ||
2127             dist_squared_to_line_v2(v2coSS, v3coSS, v1coSS) < 0.5f)
2128         {
2129                 colinear = true;
2130         }
2131         
2132         /* get the UV space bounding box */
2133         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v1coSS);
2134         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v2coSS) << 1;
2135         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v3coSS) << 2;
2136         
2137         if (inside_bucket_flag == ISECT_ALL3) {
2138                 /* is_flip_object is used here because we use the face winding */
2139                 flip = (((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != is_flip_object) !=
2140                         (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
2141
2142                 /* all screenspace points are inside the bucket bounding box,
2143                  * this means we don't need to clip and can simply return the UVs */
2144                 if (flip) { /* facing the back? */
2145                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
2146                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2147                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
2148                 }
2149                 else {
2150                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
2151                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
2152                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
2153                 }               
2154                 
2155                 *tot = 3;
2156                 return;
2157         }
2158         /* handle pathological case here, no need for further intersections below since tringle area is almost zero */
2159         if (colinear) {
2160                 int flag;
2161                 
2162                 (*tot) = 0;
2163
2164                 if (cull)
2165                         return;
2166                 
2167                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(bucket_bounds_uv[*tot], uv1co); (*tot)++; }
2168
2169                 flag = inside_bucket_flag & (ISECT_1 | ISECT_2);
2170                 if (flag && flag != (ISECT_1 | ISECT_2)) {
2171                         if (line_rect_clip(bucket_bounds, v1coSS, v2coSS, uv1co, uv2co, bucket_bounds_uv[*tot], is_ortho))
2172                                 (*tot)++;
2173                 }
2174                 
2175                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(bucket_bounds_uv[*tot], uv2co); (*tot)++; }
2176                 
2177                 flag = inside_bucket_flag & (ISECT_2 | ISECT_3);
2178                 if (flag && flag != (ISECT_2 | ISECT_3)) {
2179                         if (line_rect_clip(bucket_bounds, v2coSS, v3coSS, uv2co, uv3co, bucket_bounds_uv[*tot], is_ortho))
2180                                 (*tot)++;
2181                 }
2182
2183                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(bucket_bounds_uv[*tot], uv3co); (*tot)++; }
2184
2185                 flag = inside_bucket_flag & (ISECT_3 | ISECT_1);
2186                 if (flag && flag != (ISECT_3 | ISECT_1)) {
2187                         if (line_rect_clip(bucket_bounds, v3coSS, v1coSS, uv3co, uv1co, bucket_bounds_uv[*tot], is_ortho))
2188                                 (*tot)++;
2189                 }
2190                 
2191                 if ((*tot) < 3) {
2192                         /* no intersections to speak of, but more probable is that all face is just outside the
2193                          * rectangle and culled due to float precision issues. Since above teste have failed,
2194                          * just dump triangle as is for painting */
2195                         *tot = 0;
2196                         copy_v2_v2(bucket_bounds_uv[*tot], uv1co); (*tot)++;
2197                         copy_v2_v2(bucket_bounds_uv[*tot], uv2co); (*tot)++;
2198                         copy_v2_v2(bucket_bounds_uv[*tot], uv3co); (*tot)++;
2199                         return;
2200                 }
2201
2202                 return;
2203         }
2204
2205         /* get the UV space bounding box */
2206         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
2207         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
2208         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
2209         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
2210
2211         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
2212         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
2213         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
2214
2215         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
2216         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
2217         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
2218
2219         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
2220         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
2221         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
2222
2223         flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) !=
2224                 (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
2225
2226         if (inside_face_flag == ISECT_ALL4) {
2227                 /* bucket is totally inside the screenspace face, we can safely use weights */
2228
2229                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2230                 else rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
2231
2232                 *tot = 4;
2233                 return;
2234         }
2235         else {
2236                 /* The Complicated Case!
2237                  *
2238                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
2239                  *
2240                  * we need to make a convex polyline from the intersection between the screenspace face
2241                  * and the bucket bounds.
2242                  *
2243                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
2244                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
2245                  * do a correct clipping on both shapes. */
2246
2247
2248                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
2249
2250
2251
2252                 /* Maximum possible 6 intersections when using a rectangle and triangle */
2253                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
2254                 float v1_clipSS[2], v2_clipSS[2];
2255                 float w[3];
2256
2257                 /* calc center */
2258                 float cent[2] = {0.0f, 0.0f};
2259                 /*float up[2] = {0.0f, 1.0f};*/
2260                 int i;
2261                 bool doubles;
2262
2263                 (*tot) = 0;
2264
2265                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
2266                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
2267                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
2268                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
2269
2270                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
2271                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
2272                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
2273
2274                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
2275                         if (line_clip_rect2f(bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
2276                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2277                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2278                         }
2279                 }
2280
2281                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
2282                         if (line_clip_rect2f(bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
2283                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2284                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2285                         }
2286                 }
2287
2288                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
2289                         if (line_clip_rect2f(bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
2290                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2291                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2292                         }
2293                 }
2294
2295
2296                 if ((*tot) < 3) { /* no intersections to speak of */
2297                         *tot = 0;
2298                         return;
2299                 }
2300
2301                 /* now we have all points we need, collect their angles and sort them clockwise */
2302
2303                 for (i = 0; i < (*tot); i++) {
2304                         cent[0] += isectVCosSS[i][0];
2305                         cent[1] += isectVCosSS[i][1];
2306                 }
2307                 cent[0] = cent[0] / (float)(*tot);
2308                 cent[1] = cent[1] / (float)(*tot);
2309
2310
2311
2312                 /* Collect angles for every point around the center point */
2313
2314
2315 #if 0   /* uses a few more cycles then the above loop */
2316                 for (i = 0; i < (*tot); i++) {
2317                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
2318                 }
2319 #endif
2320
2321                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
2322                 v1_clipSS[1] = cent[1] + 1.0f;
2323
2324                 for (i = 0; i < (*tot); i++) {
2325                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2326                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2327                         isectVCosSS[i][2] = atan2f(v1_clipSS[0] * v2_clipSS[1] - v1_clipSS[1] * v2_clipSS[0],
2328                                                    v1_clipSS[0] * v2_clipSS[0] + v1_clipSS[1] * v2_clipSS[1]);
2329                 }
2330
2331                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
2332                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
2333
2334                 doubles = true;
2335                 while (doubles == true) {
2336                         doubles = false;
2337
2338                         for (i = 0; i < (*tot); i++) {
2339                                 if (fabsf(isectVCosSS[(i + 1) % *tot][0] - isectVCosSS[i][0]) < PROJ_PIXEL_TOLERANCE &&
2340                                     fabsf(isectVCosSS[(i + 1) % *tot][1] - isectVCosSS[i][1]) < PROJ_PIXEL_TOLERANCE)
2341                                 {
2342                                         int j;
2343                                         for (j = i; j < (*tot) - 1; j++) {
2344                                                 isectVCosSS[j][0] = isectVCosSS[j + 1][0];
2345                                                 isectVCosSS[j][1] = isectVCosSS[j + 1][1];
2346                                         }
2347                                         doubles = true; /* keep looking for more doubles */
2348                                         (*tot)--;
2349                                 }
2350                         }
2351                         
2352                         /* its possible there is only a few left after remove doubles */
2353                         if ((*tot) < 3) {
2354                                 // printf("removed too many doubles B\n");
2355                                 *tot = 0;
2356                                 return;
2357                         }
2358                 }
2359
2360                 if (is_ortho) {
2361                         for (i = 0; i < (*tot); i++) {
2362                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2363                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2364                         }
2365                 }
2366                 else {
2367                         for (i = 0; i < (*tot); i++) {
2368                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2369                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2370                         }
2371                 }
2372         }
2373
2374 #ifdef PROJ_DEBUG_PRINT_CLIP
2375         /* include this at the bottom of the above function to debug the output */
2376
2377         {
2378                 /* If there are ever any problems, */
2379                 float test_uv[4][2];
2380                 int i;
2381                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2382                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2383                 printf("(  [(%f,%f), (%f,%f), (%f,%f), (%f,%f)], ",
2384                        test_uv[0][0], test_uv[0][1],   test_uv[1][0], test_uv[1][1],
2385                        test_uv[2][0], test_uv[2][1],    test_uv[3][0], test_uv[3][1]);
2386
2387                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2388
2389                 printf("[");
2390                 for (i = 0; i < (*tot); i++) {
2391                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2392                 }
2393                 printf("]),\\\n");
2394         }
2395 #endif
2396 }
2397
2398 /*
2399  * # This script creates faces in a blender scene from printed data above.
2400  *
2401  * project_ls = [
2402  * ...(output from above block)...
2403  * ]
2404  *
2405  * from Blender import Scene, Mesh, Window, sys, Mathutils
2406  *
2407  * import bpy
2408  *
2409  * V = Mathutils.Vector
2410  *
2411  * def main():
2412  *     sce = bpy.data.scenes.active
2413  *
2414  *     for item in project_ls:
2415  *         bb = item[0]
2416  *         uv = item[1]
2417  *         poly = item[2]
2418  *
2419  *         me = bpy.data.meshes.new()
2420  *         ob = sce.objects.new(me)
2421  *
2422  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2423  *         me.faces.extend([(0,1,2,3),])
2424  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2425  *         me.faces.extend([(4,5,6),])
2426  *
2427  *         vs = [V(p).xyz for p in poly]
2428  *         print len(vs)
2429  *         l = len(me.verts)
2430  *         me.verts.extend(vs)
2431  *
2432  *         i = l
2433  *         while i < len(me.verts):
2434  *             ii = i + 1
2435  *             if ii == len(me.verts):
2436  *                 ii = l
2437  *             me.edges.extend([i, ii])
2438  *             i += 1
2439  *
2440  * if __name__ == '__main__':
2441  *     main()
2442  */
2443
2444
2445 #undef ISECT_1
2446 #undef ISECT_2
2447 #undef ISECT_3
2448 #undef ISECT_4
2449 #undef ISECT_ALL3
2450 #undef ISECT_ALL4
2451
2452
2453 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2454  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2455 static bool IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2456 {
2457         int i;
2458         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2459                 return 0;
2460
2461         for (i = 1; i < tot; i++) {
2462                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2463                         return 0;
2464
2465         }
2466
2467         return 1;
2468 }
2469 static bool IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2470 {
2471         int i;
2472         bool side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2473
2474         for (i = 1; i < tot; i++) {
2475                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2476                         return 0;
2477
2478         }
2479
2480         return 1;
2481 }
2482
2483 /* One of the most important function for projection painting,
2484  * since it selects the pixels to be added into each bucket.
2485  *
2486  * initialize pixels from this face where it intersects with the bucket_index,
2487  * optionally initialize pixels for removing seams */
2488 static void project_paint_face_init(
2489         const ProjPaintState *ps,
2490         const int thread_index, const int bucket_index, const int face_index, const int image_index,
2491         const rctf *bucket_bounds, ImBuf *ibuf, ImBuf **tmpibuf,
2492         const bool clamp_u, const bool clamp_v)
2493 {
2494         /* Projection vars, to get the 3D locations into screen space  */
2495         MemArena *arena = ps->arena_mt[thread_index];
2496         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2497         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2498         bool threaded = (ps->thread_tot > 1);
2499
2500         TileInfo tinf = {
2501                 ps->tile_lock,
2502                 ps->do_masking,
2503                 IMAPAINT_TILE_NUMBER(ibuf->x),
2504                 tmpibuf,
2505                 ps->projImages + image_index
2506         };
2507
2508         const MFace *mf = ps->dm_mface + face_index;
2509         const MTFace *tf = ps->dm_mtface[face_index];
2510
2511         /* UV/pixel seeking data */
2512         int x; /* Image X-Pixel */
2513         int y; /* Image Y-Pixel */
2514         float mask;
2515         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2516
2517         bool side;
2518         const float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to mf->v1,2,3 or mf->v1,3,4 */
2519
2520         float *vCo[4]; /* vertex screenspace coords */
2521
2522         float w[3], wco[3];
2523
2524         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to tf->uv[0],1,2 or tf->uv[0],2,3 */
2525         float pixelScreenCo[4];
2526         bool do_3d_mapping = ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D;
2527
2528         rcti bounds_px; /* ispace bounds */
2529         /* vars for getting uvspace bounds */
2530
2531         float tf_uv_pxoffset[4][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2532         float xhalfpx, yhalfpx;
2533         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2534
2535         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2536
2537         int i1, i2, i3;
2538
2539         float uv_clip[8][2];
2540         int uv_clip_tot;
2541         const bool is_ortho = ps->is_ortho;
2542         const bool is_flip_object = ps->is_flip_object;
2543         const bool do_backfacecull = ps->do_backfacecull;
2544         const bool do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2545
2546         vCo[0] = ps->dm_mvert[mf->v1].co;
2547         vCo[1] = ps->dm_mvert[mf->v2].co;
2548         vCo[2] = ps->dm_mvert[mf->v3].co;
2549
2550
2551         /* Use tf_uv_pxoffset instead of tf->uv so we can offset the UV half a pixel
2552          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2553          * problems when wrapping negative coords */
2554         xhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 3.0f))) / ibuf_xf;
2555         yhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 4.0f))) / ibuf_yf;
2556
2557         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2558          * Needed to add this offset since UV coords are often quads aligned to pixels.
2559          * In this case pixels can be exactly between 2 triangles causing nasty
2560          * artifacts.
2561          *
2562          * This workaround can be removed and painting will still work on most cases
2563          * but since the first thing most people try is painting onto a quad- better make it work.
2564          */
2565
2566         tf_uv_pxoffset[0][0] = tf->uv[0][0] - xhalfpx;
2567         tf_uv_pxoffset[0][1] = tf->uv[0][1] - yhalfpx;
2568
2569         tf_uv_pxoffset[1][0] = tf->uv[1][0] - xhalfpx;
2570         tf_uv_pxoffset[1][1] = tf->uv[1][1] - yhalfpx;
2571
2572         tf_uv_pxoffset[2][0] = tf->uv[2][0] - xhalfpx;
2573         tf_uv_pxoffset[2][1] = tf->uv[2][1] - yhalfpx;
2574
2575         if (mf->v4) {
2576                 vCo[3] = ps->dm_mvert[mf->v4].co;
2577
2578                 tf_uv_pxoffset[3][0] = tf->uv[3][0] - xhalfpx;
2579                 tf_uv_pxoffset[3][1] = tf->uv[3][1] - yhalfpx;
2580                 side = 1;
2581         }
2582         else {
2583                 side = 0;
2584         }
2585
2586         do {
2587                 if (side == 1) {
2588                         i1 = 0; i2 = 2; i3 = 3;
2589                 }
2590                 else {
2591                         i1 = 0; i2 = 1; i3 = 2;
2592                 }
2593
2594                 uv1co = tf_uv_pxoffset[i1]; // was tf->uv[i1];
2595                 uv2co = tf_uv_pxoffset[i2]; // was tf->uv[i2];
2596                 uv3co = tf_uv_pxoffset[i3]; // was tf->uv[i3];
2597
2598                 v1coSS = ps->screenCoords[(*(&mf->v1 + i1))];
2599                 v2coSS = ps->screenCoords[(*(&mf->v1 + i2))];
2600                 v3coSS = ps->screenCoords[(*(&mf->v1 + i3))];
2601
2602                 /* This funtion gives is a concave polyline in UV space from the clipped quad and tri*/
2603                 project_bucket_clip_face(
2604                         is_ortho, is_flip_object,
2605                         bucket_bounds,
2606                         v1coSS, v2coSS, v3coSS,
2607                         uv1co, uv2co, uv3co,
2608                         uv_clip, &uv_clip_tot,
2609                         do_backfacecull || ps->do_occlude);
2610
2611                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2612 #if 0
2613                 if (uv_clip_tot > 6) {
2614                         printf("this should never happen! %d\n", uv_clip_tot);
2615                 }
2616 #endif
2617
2618                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2619
2620                         if (clamp_u) {
2621                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2622                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2623                         }
2624
2625                         if (clamp_v) {
2626                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2627                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2628                         }
2629
2630 #if 0
2631                         project_paint_undo_tiles_init(&bounds_px, ps->projImages + image_index, tmpibuf,
2632                                                       tile_width, threaded, ps->do_masking);
2633 #endif
2634                         /* clip face and */
2635
2636                         has_isect = 0;
2637                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2638                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2639                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2640
2641                                 has_x_isect = 0;
2642                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2643                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2644                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2645
2646                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2647                                          * could check the poly direction but better to do this */
2648                                         if ((do_backfacecull == true  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2649                                             (do_backfacecull == false && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2650                                         {
2651
2652                                                 has_x_isect = has_isect = 1;
2653
2654                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2655                                                 else screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2656
2657                                                 /* a pity we need to get the worldspace pixel location here */
2658                                                 if (do_clip || do_3d_mapping) {
2659                                                         interp_v3_v3v3v3(wco, ps->dm_mvert[(*(&mf->v1 + i1))].co, ps->dm_mvert[(*(&mf->v1 + i2))].co, ps->dm_mvert[(*(&mf->v1 + i3))].co, w);
2660                                                         if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2661                                                                 continue; /* Watch out that no code below this needs to run */
2662                                                         }
2663                                                 }
2664
2665                                                 /* Is this UV visible from the view? - raytrace */
2666                                                 /* project_paint_PickFace is less complex, use for testing */
2667                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == face_index) {
2668                                                 if ((ps->do_occlude == false) ||
2669                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2670                                                 {
2671                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2672
2673                                                         if (mask > 0.0f) {
2674                                                                 BLI_linklist_prepend_arena(
2675                                                                         bucketPixelNodes,
2676                                                                         project_paint_uvpixel_init(ps, arena, &tinf, x, y, mask, face_index,
2677                                                                                                    pixelScreenCo, wco, side, w),
2678                                                                         arena
2679                                                                         );
2680                                                         }
2681                                                 }
2682
2683                                         }
2684 //#if 0
2685                                         else if (has_x_isect) {
2686                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2687                                                 break;
2688                                         }
2689 //#endif
2690                                 }
2691
2692
2693 #if 0           /* TODO - investigate why this dosnt work sometimes! it should! */
2694                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2695                                 if (has_x_isect == 0 && has_isect) {
2696                                         break;
2697                                 }
2698 #endif
2699                         }
2700                 }
2701         } while (side--);
2702
2703
2704
2705 #ifndef PROJ_DEBUG_NOSEAMBLEED
2706         if (ps->seam_bleed_px > 0.0f) {
2707                 int face_seam_flag;
2708
2709                 if (threaded)
2710                         BLI_lock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2711
2712                 face_seam_flag = ps->faceSeamFlags[face_index];
2713
2714                 /* are any of our edges un-initialized? */
2715                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_NOSEAM1)) == 0 ||
2716                     (face_seam_flag & (PROJ_FACE_SEAM2 | PROJ_FACE_NOSEAM2)) == 0 ||
2717                     (face_seam_flag & (PROJ_FACE_SEAM3 | PROJ_FACE_NOSEAM3)) == 0 ||
2718                     (face_seam_flag & (PROJ_FACE_SEAM4 | PROJ_FACE_NOSEAM4)) == 0)
2719                 {
2720                         project_face_seams_init(ps, face_index, mf->v4);
2721                         face_seam_flag = ps->faceSeamFlags[face_index];
2722                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3, flag&PROJ_FACE_SEAM4);
2723                 }
2724
2725                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_SEAM2 | PROJ_FACE_SEAM3 | PROJ_FACE_SEAM4)) == 0) {
2726
2727                         if (threaded)
2728                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2729
2730                 }
2731                 else {
2732                         /* we have a seam - deal with it! */
2733
2734                         /* Now create new UV's for the seam face */
2735                         float (*outset_uv)[2] = ps->faceSeamUVs[face_index];
2736                         float insetCos[4][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2737
2738                         float *vCoSS[4]; /* vertex screenspace coords */
2739
2740                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2741                         float edge_verts_inset_clip[2][3];
2742                         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 */
2743
2744                         float seam_subsection[4][2];
2745                         float fac1, fac2, ftot;
2746
2747                         if (outset_uv[0][0] == FLT_MAX) /* first time initialize */
2748                                 uv_image_outset(tf_uv_pxoffset, outset_uv, ps->seam_bleed_px, ibuf->x, ibuf->y, mf->v4 != 0, (ps->faceWindingFlags[face_index] & PROJ_FACE_WINDING_CW) == 0);
2749
2750                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2751                         if (threaded)
2752                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2753
2754                         vCoSS[0] = ps->screenCoords[mf->v1];
2755                         vCoSS[1] = ps->screenCoords[mf->v2];
2756                         vCoSS[2] = ps->screenCoords[mf->v3];
2757                         if (mf->v4)
2758                                 vCoSS[3] = ps->screenCoords[mf->v4];
2759
2760                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2761                         if (is_ortho) {
2762                                 if (mf->v4) scale_quad(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2763                                 else        scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2764                         }
2765                         else {
2766                                 if (mf->v4) scale_quad(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2767                                 else        scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2768                         }
2769
2770                         side = 0; /* for triangles this wont need to change */
2771
2772                         for (fidx1 = 0; fidx1 < (mf->v4 ? 4 : 3); fidx1++) {
2773                                 if (mf->v4) fidx2 = (fidx1 == 3) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2,3) -> (1,2,3,0) */
2774                                 else        fidx2 = (fidx1 == 2) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2) -> (1,2,0) */
2775
2776                                 if ((face_seam_flag & (1 << fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2777                                     line_clip_rect2f(bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1]))
2778                                 {
2779
2780                                         ftot = len_v2v2(vCoSS[fidx1], vCoSS[fidx2]); /* screenspace edge length */
2781
2782                                         if (ftot > 0.0f) { /* avoid div by zero */
2783                                                 if (mf->v4) {
2784                                                         if (fidx1 == 2 || fidx2 == 2) side = 1;
2785                                                         else side = 0;
2786                                                 }
2787
2788                                                 fac1 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[0]) / ftot;
2789                                                 fac2 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[1]) / ftot;
2790
2791                                                 interp_v2_v2v2(seam_subsection[0], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac1);
2792                                                 interp_v2_v2v2(seam_subsection[1], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac2);
2793
2794                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2795                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2796
2797                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2798                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2799                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2800                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2801
2802
2803                                                 if (pixel_bounds_uv(seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3], &bounds_px, ibuf->x, ibuf->y, true)) {
2804                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2805
2806                                                         has_isect = 0;
2807                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2808                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2809                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2810
2811                                                                 has_x_isect = 0;
2812                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2813                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2814                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2815
2816                                                                         /* test we're inside uvspace bucket and triangle bounds */
2817                                                                         if (isect_point_quad_v2(uv, seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3])) {
2818                                                                                 float fac;
2819
2820                                                                                 /* We need to find the closest point along the face edge,
2821                                                                                  * getting the screen_px_from_*** wont work because our actual location
2822                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2823                                                                                  * our location on the side of the face's UV */
2824 #if 0
2825                                                                                 if (is_ortho) screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2826                                                                                 else          screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2827 #endif
2828
2829                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2830                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2831
2832                                                                                 fac = line_point_factor_v2(uv, seam_subsection[0], seam_subsection[1]);
2833                                                                                 if      (fac < 0.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[0]); }
2834                                                                                 else if (fac > 1.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[1]); }
2835                                                                                 else                 { interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac); }
2836
2837                                                                                 if (!is_ortho) {
2838                                                                                         pixelScreenCo[3] = 1.0f;
2839                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2840                                                                                         pixelScreenCo[0] = (float)(ps->winx * 0.5f) + (ps->winx * 0.5f) * pixelScreenCo[0] / pixelScreenCo[3];
2841                                                                                         pixelScreenCo[1] = (float)(ps->winy * 0.5f) + (ps->winy * 0.5f) * pixelScreenCo[1] / pixelScreenCo[3];
2842                                                                                         pixelScreenCo[2] = pixelScreenCo[2] / pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2843                                                                                 }
2844
2845                                                                                 if ((ps->do_occlude == false) ||
2846                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2847                                                                                 {
2848                                                                                         /* Only bother calculating the weights if we intersect */
2849                                                                                         if (ps->do_mask_normal || ps->dm_mtface_clone) {
2850 #if 1
2851                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2852                                                                                                 float uv_close[2];
2853                                                                                                 float uv_fac = closest_to_line_v2(uv_close, uv, tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2]);
2854                                                                                                 if      (uv_fac < 0.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx1]);
2855                                                                                                 else if (uv_fac > 1.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx2]);
2856
2857                                                                                                 if (side) {
2858                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[2], tf_uv_pxoffset[3], uv_close, w);
2859                                                                                                 }
2860                                                                                                 else {
2861                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[1], tf_uv_pxoffset[2], uv_close, w);
2862                                                                                                 }
2863 #else                                                                                   /* this is buggy with quads, don't use for now */
2864
2865                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2866                                                                                                 uv_fac = fac1 + (uv_fac * (fac2 - fac1));
2867
2868                                                                                                 w[0] = w[1] = w[2] = 0.0;
2869                                                                                                 if (side) {
2870                                                                                                         w[fidx1 ? fidx1 - 1 : 0] = 1.0f - uv_fac;
2871                                                                                                         w[fidx2 ? fidx2 - 1 : 0] = uv_fac;
2872