Texture painting:
[blender.git] / source / blender / editors / sculpt_paint / paint_image_proj.c
1 /*
2  * ***** BEGIN GPL LICENSE BLOCK *****
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * along with this program; if not, write to the Free Software Foundation,
15  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
16  *
17  * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
18  * All rights reserved.
19  *
20  * The Original Code is: some of this file.
21  *
22  * Contributor(s): Jens Ole Wund (bjornmose), Campbell Barton (ideasman42)
23  *
24  * ***** END GPL LICENSE BLOCK *****
25  */
26
27 /** \file blender/editors/sculpt_paint/paint_image_proj.c
28  *  \ingroup edsculpt
29  *  \brief Functions to paint images in 2D and 3D.
30  */
31
32 #include <float.h>
33 #include <string.h>
34 #include <stdio.h>
35 #include <math.h>
36
37 #include "MEM_guardedalloc.h"
38
39 #ifdef WIN32
40 #  include "BLI_winstuff.h"
41 #endif
42
43 #include "BLI_blenlib.h"
44 #include "BLI_linklist.h"
45 #include "BLI_math.h"
46 #include "BLI_math_color_blend.h"
47 #include "BLI_memarena.h"
48 #include "BLI_threads.h"
49 #include "BLI_utildefines.h"
50
51 #include "BLF_translation.h"
52
53 #include "PIL_time.h"
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_colortools.h"
66 #include "BKE_context.h"
67 #include "BKE_depsgraph.h"
68 #include "BKE_DerivedMesh.h"
69 #include "BKE_idprop.h"
70 #include "BKE_brush.h"
71 #include "BKE_image.h"
72 #include "BKE_library.h"
73 #include "BKE_main.h"
74 #include "BKE_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_view2d.h"
84 #include "UI_interface.h"
85
86 #include "ED_image.h"
87 #include "ED_mesh.h"
88 #include "ED_node.h"
89 #include "ED_paint.h"
90 #include "ED_screen.h"
91 #include "ED_uvedit.h"
92 #include "ED_view3d.h"
93
94 #include "GPU_extensions.h"
95
96 #include "WM_api.h"
97 #include "WM_types.h"
98
99 #include "RNA_access.h"
100 #include "RNA_define.h"
101 #include "RNA_enum_types.h"
102
103 #include "GPU_draw.h"
104 #include "GPU_buffers.h"
105
106 #include "IMB_colormanagement.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 /* projectFaceSeamFlags options */
139 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
140 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
141 #define PROJ_FACE_SEAM1 (1 << 0)  /* If this face has a seam on any of its edges */
142 #define PROJ_FACE_SEAM2 (1 << 1)
143 #define PROJ_FACE_SEAM3 (1 << 2)
144 #define PROJ_FACE_SEAM4 (1 << 3)
145
146 #define PROJ_FACE_NOSEAM1   (1 << 4)
147 #define PROJ_FACE_NOSEAM2   (1 << 5)
148 #define PROJ_FACE_NOSEAM3   (1 << 6)
149 #define PROJ_FACE_NOSEAM4   (1 << 7)
150
151 /* face winding */
152 #define PROJ_FACE_WINDING_INIT 1
153 #define PROJ_FACE_WINDING_CW 2
154
155 #define PROJ_SRC_VIEW       1
156 #define PROJ_SRC_IMAGE_CAM  2
157 #define PROJ_SRC_IMAGE_VIEW 3
158 #define PROJ_SRC_VIEW_FILL  4
159
160 #define PROJ_VIEW_DATA_ID "view_data"
161 #define PROJ_VIEW_DATA_SIZE (4 * 4 + 4 * 4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
162
163
164 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
165  * as this number approaches  1.0f the likelihood increases of float precision errors where
166  * it is occluded by an adjacent face */
167 #define PROJ_FACE_SCALE_SEAM    0.99f
168
169 #define PROJ_BUCKET_NULL        0
170 #define PROJ_BUCKET_INIT        (1 << 0)
171 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
172
173 /* used for testing doubles, if a point is on a line etc */
174 #define PROJ_GEOM_TOLERANCE 0.00075f
175 #define PROJ_PIXEL_TOLERANCE 0.01f
176
177 /* vert flags */
178 #define PROJ_VERT_CULL 1
179
180 /* to avoid locking in tile initialization */
181 #define TILE_PENDING SET_INT_IN_POINTER(-1)
182
183 /* This is mainly a convenience struct used so we can keep an array of images we use
184  * Thir imbufs, etc, in 1 array, When using threads this array is copied for each thread
185  * because 'partRedrawRect' and 'touch' values would not be thread safe */
186 typedef struct ProjPaintImage {
187         Image *ima;
188         ImBuf *ibuf;
189         ImagePaintPartialRedraw *partRedrawRect;
190         volatile void **undoRect; /* only used to build undo tiles during painting */
191         unsigned short **maskRect; /* the mask accumulation must happen on canvas, not on space screen bucket.
192                           * Here we store the mask rectangle */
193         bool **valid; /* store flag to enforce validation of undo rectangle */
194         int touch;
195 } ProjPaintImage;
196
197 /* Main projection painting struct passed to all projection painting functions */
198 typedef struct ProjPaintState {
199         View3D *v3d;
200         RegionView3D *rv3d;
201         ARegion *ar;
202         Scene *scene;
203         int source; /* PROJ_SRC_**** */
204
205         /* the paint color. It can change depending of inverted mode or not */
206         float paint_color[3];
207         float paint_color_linear[3];
208
209         Brush *brush;
210         short tool, blend, mode;
211         int orig_brush_size;
212         float brush_size;
213         Object *ob;
214         /* end similarities with ImagePaintState */
215
216         DerivedMesh    *dm;
217         int dm_totface;
218         int dm_totvert;
219         int dm_release;
220
221         MVert          *dm_mvert;
222         MFace          *dm_mface;
223         MTFace         **dm_mtface;
224         MTFace         **dm_mtface_clone;    /* other UV map, use for cloning between layers */
225         MTFace         *dm_mtface_stencil;
226
227         Image *stencil_ima;
228         Image *canvas_ima;
229         Image *clone_ima;
230         float stencil_value;
231
232         /* projection painting only */
233         MemArena *arena_mt[BLENDER_MAX_THREADS]; /* for multithreading, the first item is sometimes used for non threaded cases too */
234         LinkNode **bucketRect;              /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
235         LinkNode **bucketFaces;             /* bucketRect aligned array linkList of faces overlapping each bucket */
236         unsigned char *bucketFlags;         /* store if the bucks have been initialized  */
237 #ifndef PROJ_DEBUG_NOSEAMBLEED
238         char *faceSeamFlags;                /* store info about faces, if they are initialized etc*/
239         char *faceWindingFlags;             /* save the winding of the face in uv space, helps as an extra validation step for seam detection */
240         float (*faceSeamUVs)[4][2];         /* expanded UVs for faces to use as seams */
241         LinkNode **vertFaces;               /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
242 #endif
243         char *vertFlags;                    /* store options per vert, now only store if the vert is pointing away from the view */
244         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 */
245         int buckets_y;
246
247         ProjPaintImage *projImages;
248
249         int pixel_sizeof;           /* result of project_paint_pixel_sizeof(), constant per stroke */
250
251         int image_tot;              /* size of projectImages array */
252
253         float (*screenCoords)[4];   /* verts projected into floating point screen space */
254
255         float screenMin[2];         /* 2D bounds for mesh verts on the screen's plane (screenspace) */
256         float screenMax[2];
257         float screen_width;         /* Calculated from screenMin & screenMax */
258         float screen_height;
259         int winx, winy;             /* from the carea or from the projection render */
260
261         /* options for projection painting */
262         bool  do_layer_clone;
263         bool  do_layer_stencil;
264         bool  do_layer_stencil_inv;
265         bool  do_stencil_brush;
266         bool  do_material_slots;
267
268         bool  do_occlude;               /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
269         bool  do_backfacecull;          /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
270         bool  do_mask_normal;           /* mask out pixels based on their normals */
271         bool  do_new_shading_nodes;     /* cache BKE_scene_use_new_shading_nodes value */
272         float normal_angle;             /* what angle to mask at*/
273         float normal_angle_inner;
274         float normal_angle_range;       /* difference between normal_angle and normal_angle_inner, for easy access */
275
276         bool do_face_sel;               /* quick access to (me->editflag & ME_EDIT_PAINT_FACE_SEL) */
277         bool is_ortho;
278         bool do_masking;              /* use masking during painting. Some operations such as airbrush may disable */
279         bool is_texbrush;              /* only to avoid running  */
280         bool is_maskbrush;            /* mask brush is applied before masking */
281 #ifndef PROJ_DEBUG_NOSEAMBLEED
282         float seam_bleed_px;
283 #endif
284         /* clone vars */
285         float cloneOffset[2];
286
287         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
288         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
289         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
290         float clipsta, clipend;
291
292         /* reproject vars */
293         Image *reproject_image;
294         ImBuf *reproject_ibuf;
295
296         /* threads */
297         int thread_tot;
298         int bucketMin[2];
299         int bucketMax[2];
300         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
301
302         /* redraw */
303         bool need_redraw;
304
305         BlurKernel *blurkernel;
306
307         SpinLock *tile_lock;
308 } ProjPaintState;
309
310 typedef union pixelPointer {
311         float *f_pt;            /* float buffer */
312         unsigned int *uint_pt; /* 2 ways to access a char buffer */
313         unsigned char *ch_pt;
314 } PixelPointer;
315
316 typedef union pixelStore {
317         unsigned char ch[4];
318         unsigned int uint;
319         float f[4];
320 } PixelStore;
321
322 typedef struct ProjPixel {
323         float projCoSS[2]; /* the floating point screen projection of this pixel */
324         float worldCoSS[3];
325         /* Only used when the airbrush is disabled.
326          * Store the max mask value to avoid painting over an area with a lower opacity
327          * with an advantage that we can avoid touching the pixel at all, if the
328          * new mask value is lower then mask_accum */
329         unsigned short *mask_accum;
330
331         /* for various reasons we may want to mask out painting onto this pixel */
332         unsigned short mask;
333
334         short x_px, y_px;
335         /* horrible hack, store tile valid flag pointer here to re-validate tiles used for anchored and drag-dot strokes */
336         bool *valid;
337
338         PixelPointer origColor;
339         PixelStore newColor;
340         PixelPointer pixel;
341
342         short image_index; /* if anyone wants to paint onto more than 32768 images they can bite me */
343         unsigned char bb_cell_index;
344 } ProjPixel;
345
346 typedef struct ProjPixelClone {
347         struct ProjPixel __pp;
348         PixelStore clonepx;
349 } ProjPixelClone;
350
351 /* undo tile pushing */
352 typedef struct {
353         SpinLock *lock;
354         bool masked;
355         unsigned short tile_width;
356         ImBuf **tmpibuf;
357         ProjPaintImage *pjima;
358 } TileInfo;
359
360
361 /* Finish projection painting structs */
362
363 static TexPaintSlot *project_paint_face_paint_slot(const ProjPaintState *ps, int face_index)
364 {
365         MFace *mf = ps->dm_mface + face_index;
366         Material *ma = ps->dm->mat[mf->mat_nr];
367         return ma ? ma->texpaintslot + ma->paint_active_slot : NULL;
368 }
369
370 static Image *project_paint_face_paint_image(const ProjPaintState *ps, int face_index)
371 {
372         if (ps->do_stencil_brush) {
373                 return ps->stencil_ima;
374         }
375         else {
376                 MFace *mf = ps->dm_mface + face_index;
377                 Material *ma = ps->dm->mat[mf->mat_nr];
378                 TexPaintSlot *slot = ma ? ma->texpaintslot + ma->paint_active_slot : NULL;
379                 return slot ? slot->ima : ps->canvas_ima;
380         }
381 }
382
383 static TexPaintSlot *project_paint_face_clone_slot(const ProjPaintState *ps, int face_index)
384 {
385         MFace *mf = ps->dm_mface + face_index;
386         Material *ma = ps->dm->mat[mf->mat_nr];
387         return ma ? ma->texpaintslot + ma->paint_clone_slot : NULL;
388 }
389
390 static Image *project_paint_face_clone_image(const ProjPaintState *ps, int face_index)
391 {
392         MFace *mf = ps->dm_mface + face_index;
393         Material *ma = ps->dm->mat[mf->mat_nr];
394         TexPaintSlot *slot = ma ? ma->texpaintslot + ma->paint_clone_slot : NULL;
395         return slot ? slot->ima : ps->clone_ima;
396 }
397
398 /* fast projection bucket array lookup, use the safe version for bound checking  */
399 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
400 {
401         /* If we were not dealing with screenspace 2D coords we could simple do...
402          * ps->bucketRect[x + (y*ps->buckets_y)] */
403
404         /* please explain?
405          * projCoSS[0] - ps->screenMin[0]   : zero origin
406          * ... / ps->screen_width           : range from 0.0 to 1.0
407          * ... * ps->buckets_x              : use as a bucket index
408          *
409          * Second multiplication does similar but for vertical offset
410          */
411         return ( (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
412                (((int)(((projCoSS[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
413 }
414
415 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
416 {
417         int bucket_index = project_bucket_offset(ps, projCoSS);
418
419         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
420                 return -1;
421         }
422         else {
423                 return bucket_index;
424         }
425 }
426
427 static float VecZDepthOrtho(const float pt[2],
428                             const float v1[3], const float v2[3], const float v3[3],
429                             float w[3])
430 {
431         barycentric_weights_v2(v1, v2, v3, pt, w);
432         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
433 }
434
435 static float VecZDepthPersp(const float pt[2],
436                             const float v1[4], const float v2[4], const float v3[4],
437                             float w[3])
438 {
439         float wtot_inv, wtot;
440         float w_tmp[3];
441
442         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
443         /* for the depth we need the weights to match what
444          * barycentric_weights_v2 would return, in this case its easiest just to
445          * undo the 4th axis division and make it unit-sum
446          *
447          * don't call barycentric_weights_v2() because our callers expect 'w'
448          * to be weighted from the perspective */
449         w_tmp[0] = w[0] * v1[3];
450         w_tmp[1] = w[1] * v2[3];
451         w_tmp[2] = w[2] * v3[3];
452
453         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
454
455         if (wtot != 0.0f) {
456                 wtot_inv = 1.0f / wtot;
457
458                 w_tmp[0] = w_tmp[0] * wtot_inv;
459                 w_tmp[1] = w_tmp[1] * wtot_inv;
460                 w_tmp[2] = w_tmp[2] * wtot_inv;
461         }
462         else /* dummy values for zero area face */
463                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
464         /* done mimicing barycentric_weights_v2() */
465
466         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
467 }
468
469
470 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
471 static int project_paint_PickFace(const ProjPaintState *ps, const float pt[2], float w[3], int *side)
472 {
473         LinkNode *node;
474         float w_tmp[3];
475         const float *v1, *v2, *v3, *v4;
476         int bucket_index;
477         int face_index;
478         int best_side = -1;
479         int best_face_index = -1;
480         float z_depth_best = FLT_MAX, z_depth;
481         MFace *mf;
482
483         bucket_index = project_bucket_offset_safe(ps, pt);
484         if (bucket_index == -1)
485                 return -1;
486
487
488
489         /* we could return 0 for 1 face buckets, as long as this function assumes
490          * that the point its testing is only every originated from an existing face */
491
492         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
493                 face_index = GET_INT_FROM_POINTER(node->link);
494                 mf = ps->dm_mface + face_index;
495
496                 v1 = ps->screenCoords[mf->v1];
497                 v2 = ps->screenCoords[mf->v2];
498                 v3 = ps->screenCoords[mf->v3];
499
500                 if (isect_point_tri_v2(pt, v1, v2, v3)) {
501                         if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v2, v3, w_tmp);
502                         else z_depth = VecZDepthPersp(pt, v1, v2, v3, w_tmp);
503
504                         if (z_depth < z_depth_best) {
505                                 best_face_index = face_index;
506                                 best_side = 0;
507                                 z_depth_best = z_depth;
508                                 copy_v3_v3(w, w_tmp);
509                         }
510                 }
511                 else if (mf->v4) {
512                         v4 = ps->screenCoords[mf->v4];
513
514                         if (isect_point_tri_v2(pt, v1, v3, v4)) {
515                                 if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v3, v4, w_tmp);
516                                 else z_depth = VecZDepthPersp(pt, v1, v3, v4, w_tmp);
517
518                                 if (z_depth < z_depth_best) {
519                                         best_face_index = face_index;
520                                         best_side = 1;
521                                         z_depth_best = z_depth;
522                                         copy_v3_v3(w, w_tmp);
523                                 }
524                         }
525                 }
526         }
527
528         *side = best_side;
529         return best_face_index; /* will be -1 or a valid face */
530 }
531
532 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
533 static void uvco_to_wrapped_pxco(const float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
534 {
535         /* use */
536         *x = fmodf(uv[0], 1.0f);
537         *y = fmodf(uv[1], 1.0f);
538
539         if (*x < 0.0f) *x += 1.0f;
540         if (*y < 0.0f) *y += 1.0f;
541
542         *x = *x * ibuf_x - 0.5f;
543         *y = *y * ibuf_y - 0.5f;
544 }
545
546 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
547 static bool project_paint_PickColor(const ProjPaintState *ps, const float pt[2],
548                                     float *rgba_fp, unsigned char *rgba, const bool interp)
549 {
550         float w[3], uv[2];
551         int side;
552         int face_index;
553         MTFace *tf;
554         Image *ima;
555         ImBuf *ibuf;
556         int xi, yi;
557
558
559         face_index = project_paint_PickFace(ps, pt, w, &side);
560
561         if (face_index == -1)
562                 return 0;
563
564         tf = *(ps->dm_mtface + face_index);
565
566         if (side == 0) {
567                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[1], tf->uv[2], w);
568         }
569         else { /* QUAD */
570                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[2], tf->uv[3], w);
571         }
572
573         ima = project_paint_face_paint_image(ps, face_index);
574         ibuf = BKE_image_get_first_ibuf(ima); /* we must have got the imbuf before getting here */
575         if (!ibuf) return 0;
576
577         if (interp) {
578                 float x, y;
579                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
580
581                 if (ibuf->rect_float) {
582                         if (rgba_fp) {
583                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
584                         }
585                         else {
586                                 float rgba_tmp_f[4];
587                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
588                                 premul_float_to_straight_uchar(rgba, rgba_tmp_f);
589                         }
590                 }
591                 else {
592                         if (rgba) {
593                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
594                         }
595                         else {
596                                 unsigned char rgba_tmp[4];
597                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
598                                 straight_uchar_to_premul_float(rgba_fp, rgba_tmp);
599                         }
600                 }
601         }
602         else {
603                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
604                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
605                 //if (xi < 0 || xi >= ibuf->x  ||  yi < 0 || yi >= ibuf->y) return 0;
606
607                 /* wrap */
608                 xi = mod_i((int)(uv[0] * ibuf->x), ibuf->x);
609                 yi = mod_i((int)(uv[1] * ibuf->y), ibuf->y);
610
611                 if (rgba) {
612                         if (ibuf->rect_float) {
613                                 const float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
614                                 premul_float_to_straight_uchar(rgba, rgba_tmp_fp);
615                         }
616                         else {
617                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
618                         }
619                 }
620
621                 if (rgba_fp) {
622                         if (ibuf->rect_float) {
623                                 copy_v4_v4(rgba_fp, (ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
624                         }
625                         else {
626                                 unsigned char *tmp_ch = ((unsigned char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
627                                 straight_uchar_to_premul_float(rgba_fp, tmp_ch);
628                         }
629                 }
630         }
631         BKE_image_release_ibuf(ima, ibuf, NULL);
632         return 1;
633 }
634
635 /* Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusuion test)
636  * return...
637  *  0   : no occlusion
638  * -1   : no occlusion but 2D intersection is true (avoid testing the other half of a quad)
639  *  1   : occluded
640  *  2   : occluded with w[3] weights set (need to know in some cases) */
641
642 static int project_paint_occlude_ptv(const float pt[3],
643                                      const float v1[4], const float v2[4], const float v3[4],
644                                      float w[3], const bool is_ortho)
645 {
646         /* if all are behind us, return false */
647         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
648                 return 0;
649
650         /* do a 2D point in try intersection */
651         if (!isect_point_tri_v2(pt, v1, v2, v3))
652                 return 0;  /* we know there is  */
653
654
655         /* From here on we know there IS an intersection */
656         /* if ALL of the verts are infront of us then we know it intersects ? */
657         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
658                 return 1;
659         }
660         else {
661                 /* we intersect? - find the exact depth at the point of intersection */
662                 /* Is this point is occluded by another face? */
663                 if (is_ortho) {
664                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
665                 }
666                 else {
667                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
668                 }
669         }
670         return -1;
671 }
672
673
674 static int project_paint_occlude_ptv_clip(const ProjPaintState *ps, const MFace *mf,
675                                           const float pt[3], const float v1[4], const float v2[4], const float v3[4],
676                                           const int side)
677 {
678         float w[3], wco[3];
679         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, ps->is_ortho);
680
681         if (ret <= 0)
682                 return ret;
683
684         if (ret == 1) { /* weights not calculated */
685                 if (ps->is_ortho) barycentric_weights_v2(v1, v2, v3, pt, w);
686                 else barycentric_weights_v2_persp(v1, v2, v3, pt, w);
687         }
688
689         /* Test if we're in the clipped area, */
690         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);
691         else interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
692
693         if (!ED_view3d_clipping_test(ps->rv3d, wco, true)) {
694                 return 1;
695         }
696
697         return -1;
698 }
699
700
701 /* Check if a screenspace location is occluded by any other faces
702  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
703  * and doesn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
704 static bool project_bucket_point_occluded(const ProjPaintState *ps, LinkNode *bucketFace,
705                                           const int orig_face, const float pixelScreenCo[4])
706 {
707         MFace *mf;
708         int face_index;
709         int isect_ret;
710         float w[3]; /* not needed when clipping */
711         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
712
713         /* we could return 0 for 1 face buckets, as long as this function assumes
714          * that the point its testing is only every originated from an existing face */
715
716         for (; bucketFace; bucketFace = bucketFace->next) {
717                 face_index = GET_INT_FROM_POINTER(bucketFace->link);
718
719                 if (orig_face != face_index) {
720                         mf = ps->dm_mface + face_index;
721                         if (do_clip)
722                                 isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], 0);
723                         else
724                                 isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], w, ps->is_ortho);
725
726                         /* Note, if (isect_ret == -1) then we don't want to test the other side of the quad */
727                         if (isect_ret == 0 && mf->v4) {
728                                 if (do_clip)
729                                         isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], 1);
730                                 else
731                                         isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], w, ps->is_ortho);
732                         }
733                         if (isect_ret >= 1) {
734                                 /* TODO - we may want to cache the first hit,
735                                  * it is not possible to swap the face order in the list anymore */
736                                 return true;
737                         }
738                 }
739         }
740         return false;
741 }
742
743 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
744  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
745 #define ISECT_TRUE 1
746 #define ISECT_TRUE_P1 2
747 #define ISECT_TRUE_P2 3
748 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
749 {
750         float y_diff;
751
752         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
753                 *x_isect = p1[0];
754                 return ISECT_TRUE_P1;
755         }
756         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
757                 *x_isect = p2[0];
758                 return ISECT_TRUE_P2;
759         }
760
761         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
762
763         if (y_diff < 0.000001f) {
764                 *x_isect = (p1[0] + p2[0]) * 0.5f;
765                 return ISECT_TRUE;
766         }
767
768         if (p1[1] > y_level && p2[1] < y_level) {
769                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /*(p1[1]-p2[1]);*/
770                 return ISECT_TRUE;
771         }
772         else if (p1[1] < y_level && p2[1] > y_level) {
773                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /*(p2[1]-p1[1]);*/
774                 return ISECT_TRUE;
775         }
776         else {
777                 return 0;
778         }
779 }
780
781 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
782 {
783         float x_diff;
784
785         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
786                 *y_isect = p1[1];
787                 return ISECT_TRUE_P1;
788         }
789         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
790                 *y_isect = p2[1];
791                 return ISECT_TRUE_P2;
792         }
793
794         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
795
796         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
797                 *y_isect = (p1[0] + p2[0]) * 0.5f;
798                 return ISECT_TRUE;
799         }
800
801         if (p1[0] > x_level && p2[0] < x_level) {
802                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff; /*(p1[0]-p2[0]);*/
803                 return ISECT_TRUE;
804         }
805         else if (p1[0] < x_level && p2[0] > x_level) {
806                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff; /*(p2[0]-p1[0]);*/
807                 return ISECT_TRUE;
808         }
809         else {
810                 return 0;
811         }
812 }
813
814 /* simple func use for comparing UV locations to check if there are seams.
815  * Its possible this gives incorrect results, when the UVs for 1 face go into the next
816  * tile, but do not do this for the adjacent face, it could return a false positive.
817  * This is so unlikely that Id not worry about it. */
818 #ifndef PROJ_DEBUG_NOSEAMBLEED
819 static bool cmp_uv(const float vec2a[2], const float vec2b[2])
820 {
821         /* if the UV's are not between 0.0 and 1.0 */
822         float xa = fmodf(vec2a[0], 1.0f);
823         float ya = fmodf(vec2a[1], 1.0f);
824
825         float xb = fmodf(vec2b[0], 1.0f);
826         float yb = fmodf(vec2b[1], 1.0f);
827
828         if (xa < 0.0f) xa += 1.0f;
829         if (ya < 0.0f) ya += 1.0f;
830
831         if (xb < 0.0f) xb += 1.0f;
832         if (yb < 0.0f) yb += 1.0f;
833
834         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
835 }
836 #endif
837
838 /* set min_px and max_px to the image space bounds of the UV coords
839  * return zero if there is no area in the returned rectangle */
840 #ifndef PROJ_DEBUG_NOSEAMBLEED
841 static bool pixel_bounds_uv(
842         const float uv1[2], const float uv2[2], const float uv3[2], const float uv4[2],
843         rcti *bounds_px,
844         const int ibuf_x, const int ibuf_y,
845         const bool is_quad
846         )
847 {
848         float min_uv[2], max_uv[2]; /* UV bounds */
849
850         INIT_MINMAX2(min_uv, max_uv);
851
852         minmax_v2v2_v2(min_uv, max_uv, uv1);
853         minmax_v2v2_v2(min_uv, max_uv, uv2);
854         minmax_v2v2_v2(min_uv, max_uv, uv3);
855         if (is_quad)
856                 minmax_v2v2_v2(min_uv, max_uv, uv4);
857
858         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
859         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
860
861         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
862         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
863
864         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
865
866         /* face uses no UV area when quantized to pixels? */
867         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
868 }
869 #endif
870
871 static bool pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
872 {
873         float min_uv[2], max_uv[2]; /* UV bounds */
874
875         if (tot == 0) {
876                 return 0;
877         }
878
879         INIT_MINMAX2(min_uv, max_uv);
880
881         while (tot--) {
882                 minmax_v2v2_v2(min_uv, max_uv, (*uv));
883                 uv++;
884         }
885
886         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
887         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
888
889         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
890         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
891
892         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
893
894         /* face uses no UV area when quantized to pixels? */
895         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
896 }
897
898 #ifndef PROJ_DEBUG_NOSEAMBLEED
899
900 static void project_face_winding_init(const ProjPaintState *ps, const int face_index)
901 {
902         /* detect the winding of faces in uv space */
903         MTFace *tf = ps->dm_mtface[face_index];
904         float winding = cross_tri_v2(tf->uv[0], tf->uv[1], tf->uv[2]);
905
906         if (ps->dm_mface[face_index].v4)
907                 winding += cross_tri_v2(tf->uv[2], tf->uv[3], tf->uv[0]);
908
909         if (winding > 0)
910                 ps->faceWindingFlags[face_index] |= PROJ_FACE_WINDING_CW;
911
912         ps->faceWindingFlags[face_index] |= PROJ_FACE_WINDING_INIT;
913 }
914
915 /* This function returns 1 if this face has a seam along the 2 face-vert indices
916  * 'orig_i1_fidx' and 'orig_i2_fidx' */
917 static bool check_seam(const ProjPaintState *ps,
918                        const int orig_face, const int orig_i1_fidx, const int orig_i2_fidx,
919                        int *other_face, int *orig_fidx)
920 {
921         LinkNode *node;
922         int face_index;
923         unsigned int i1, i2;
924         int i1_fidx = -1, i2_fidx = -1; /* index in face */
925         MFace *mf;
926         MTFace *tf;
927         const MFace *orig_mf = ps->dm_mface + orig_face;
928         const MTFace *orig_tf = ps->dm_mtface[orig_face];
929
930         /* vert indices from face vert order indices */
931         i1 = (*(&orig_mf->v1 + orig_i1_fidx));
932         i2 = (*(&orig_mf->v1 + orig_i2_fidx));
933
934         for (node = ps->vertFaces[i1]; node; node = node->next) {
935                 face_index = GET_INT_FROM_POINTER(node->link);
936
937                 if (face_index != orig_face) {
938                         mf = ps->dm_mface + face_index;
939                         /* could check if the 2 faces images match here,
940                          * but then there wouldn't be a way to return the opposite face's info */
941
942
943                         /* We need to know the order of the verts in the adjacent face
944                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
945                         i1_fidx = BKE_MESH_TESSFACE_VINDEX_ORDER(mf, i1);
946                         i2_fidx = BKE_MESH_TESSFACE_VINDEX_ORDER(mf, i2);
947
948                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
949                         if (i2_fidx != -1) {
950                                 Image *tpage = project_paint_face_paint_image(ps, face_index);
951                                 Image *orig_tpage = project_paint_face_paint_image(ps, orig_face);
952
953                                 BLI_assert(i1_fidx != -1);
954
955                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
956                                 tf = ps->dm_mtface[face_index];
957
958                                 /* set up the other face */
959                                 *other_face = face_index;
960                                 
961                                 /* we check if difference is 1 here, else we might have a case of edge 2-0 or 3-0 for quads */
962                                 *orig_fidx = (i1_fidx < i2_fidx && (i2_fidx - i1_fidx == 1)) ? i1_fidx : i2_fidx;
963
964                                 /* initialize face winding if needed */
965                                 if ((ps->faceWindingFlags[face_index] & PROJ_FACE_WINDING_INIT) == 0)
966                                         project_face_winding_init(ps, face_index);
967
968                                 /* first test if they have the same image */
969                                 if ((orig_tpage == tpage) &&
970                                     cmp_uv(orig_tf->uv[orig_i1_fidx], tf->uv[i1_fidx]) &&
971                                     cmp_uv(orig_tf->uv[orig_i2_fidx], tf->uv[i2_fidx]))
972                                 {
973                                         /* if faces don't have the same winding in uv space,
974                                          * they are on the same side so edge is boundary */
975                                         if ((ps->faceWindingFlags[face_index] & PROJ_FACE_WINDING_CW) !=
976                                             (ps->faceWindingFlags[orig_face] & PROJ_FACE_WINDING_CW))
977                                         {
978                                                 return 1;
979                                         }
980
981                                         // printf("SEAM (NONE)\n");
982                                         return 0;
983
984                                 }
985                                 else {
986                                         // printf("SEAM (UV GAP)\n");
987                                         return 1;
988                                 }
989                         }
990                 }
991         }
992         // printf("SEAM (NO FACE)\n");
993         *other_face = -1;
994         return 1;
995 }
996
997 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
998  * since the outset coords are a margin that keep an even distance from the original UV's,
999  * note that the image aspect is taken into account */
1000 static void uv_image_outset(float (*orig_uv)[2], float (*outset_uv)[2], const float scaler,
1001                             const int ibuf_x, const int ibuf_y, const bool is_quad)
1002 {
1003         float a1, a2, a3, a4 = 0.0f;
1004         float puv[4][2]; /* pixelspace uv's */
1005         float no1[2], no2[2], no3[2], no4[2]; /* normals */
1006         float dir1[2], dir2[2], dir3[2], dir4[2];
1007         float ibuf_inv[2];
1008
1009         ibuf_inv[0] = 1.0f / (float)ibuf_x;
1010         ibuf_inv[1] = 1.0f / (float)ibuf_y;
1011
1012         /* make UV's in pixel space so we can */
1013         puv[0][0] = orig_uv[0][0] * ibuf_x;
1014         puv[0][1] = orig_uv[0][1] * ibuf_y;
1015
1016         puv[1][0] = orig_uv[1][0] * ibuf_x;
1017         puv[1][1] = orig_uv[1][1] * ibuf_y;
1018
1019         puv[2][0] = orig_uv[2][0] * ibuf_x;
1020         puv[2][1] = orig_uv[2][1] * ibuf_y;
1021
1022         if (is_quad) {
1023                 puv[3][0] = orig_uv[3][0] * ibuf_x;
1024                 puv[3][1] = orig_uv[3][1] * ibuf_y;
1025         }
1026
1027         /* face edge directions */
1028         sub_v2_v2v2(dir1, puv[1], puv[0]);
1029         sub_v2_v2v2(dir2, puv[2], puv[1]);
1030         normalize_v2(dir1);
1031         normalize_v2(dir2);
1032
1033         if (is_quad) {
1034                 sub_v2_v2v2(dir3, puv[3], puv[2]);
1035                 sub_v2_v2v2(dir4, puv[0], puv[3]);
1036                 normalize_v2(dir3);
1037                 normalize_v2(dir4);
1038         }
1039         else {
1040                 sub_v2_v2v2(dir3, puv[0], puv[2]);
1041                 normalize_v2(dir3);
1042         }
1043
1044         if (is_quad) {
1045                 a1 = shell_v2v2_mid_normalized_to_dist(dir4, dir1);
1046                 a2 = shell_v2v2_mid_normalized_to_dist(dir1, dir2);
1047                 a3 = shell_v2v2_mid_normalized_to_dist(dir2, dir3);
1048                 a4 = shell_v2v2_mid_normalized_to_dist(dir3, dir4);
1049         }
1050         else {
1051                 a1 = shell_v2v2_mid_normalized_to_dist(dir3, dir1);
1052                 a2 = shell_v2v2_mid_normalized_to_dist(dir1, dir2);
1053                 a3 = shell_v2v2_mid_normalized_to_dist(dir2, dir3);
1054         }
1055
1056         if (is_quad) {
1057                 sub_v2_v2v2(no1, dir4, dir1);
1058                 sub_v2_v2v2(no2, dir1, dir2);
1059                 sub_v2_v2v2(no3, dir2, dir3);
1060                 sub_v2_v2v2(no4, dir3, dir4);
1061                 normalize_v2(no1);
1062                 normalize_v2(no2);
1063                 normalize_v2(no3);
1064                 normalize_v2(no4);
1065                 mul_v2_fl(no1, a1 * scaler);
1066                 mul_v2_fl(no2, a2 * scaler);
1067                 mul_v2_fl(no3, a3 * scaler);
1068                 mul_v2_fl(no4, a4 * scaler);
1069                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1070                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1071                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1072                 add_v2_v2v2(outset_uv[3], puv[3], no4);
1073                 mul_v2_v2(outset_uv[0], ibuf_inv);
1074                 mul_v2_v2(outset_uv[1], ibuf_inv);
1075                 mul_v2_v2(outset_uv[2], ibuf_inv);
1076                 mul_v2_v2(outset_uv[3], ibuf_inv);
1077         }
1078         else {
1079                 sub_v2_v2v2(no1, dir3, dir1);
1080                 sub_v2_v2v2(no2, dir1, dir2);
1081                 sub_v2_v2v2(no3, dir2, dir3);
1082                 normalize_v2(no1);
1083                 normalize_v2(no2);
1084                 normalize_v2(no3);
1085                 mul_v2_fl(no1, a1 * scaler);
1086                 mul_v2_fl(no2, a2 * scaler);
1087                 mul_v2_fl(no3, a3 * scaler);
1088                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1089                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1090                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1091
1092                 mul_v2_v2(outset_uv[0], ibuf_inv);
1093                 mul_v2_v2(outset_uv[1], ibuf_inv);
1094                 mul_v2_v2(outset_uv[2], ibuf_inv);
1095         }
1096 }
1097
1098 /*
1099  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1100  * 1<<i - where i is (0-3)
1101  *
1102  * If we're multithreadng, make sure threads are locked when this is called
1103  */
1104 static void project_face_seams_init(const ProjPaintState *ps, const int face_index, const int is_quad)
1105 {
1106         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1107         int fidx1 = is_quad ? 3 : 2;
1108         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 */
1109
1110         /* initialize face winding if needed */
1111         if ((ps->faceWindingFlags[face_index] & PROJ_FACE_WINDING_INIT) == 0)
1112                 project_face_winding_init(ps, face_index);
1113
1114         do {
1115                 if ((ps->faceSeamFlags[face_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1116                         if (check_seam(ps, face_index, fidx1, fidx2, &other_face, &other_fidx)) {
1117                                 ps->faceSeamFlags[face_index] |= 1 << fidx1;
1118                                 if (other_face != -1)
1119                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1120                         }
1121                         else {
1122                                 ps->faceSeamFlags[face_index] |= 16 << fidx1;
1123                                 if (other_face != -1)
1124                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1125                         }
1126                 }
1127
1128                 fidx2 = fidx1;
1129         } while (fidx1--);
1130 }
1131 #endif // PROJ_DEBUG_NOSEAMBLEED
1132
1133
1134 /* Converts a UV location to a 3D screenspace location
1135  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1136  *
1137  * This is used for finding a pixels location in screenspace for painting */
1138 static void screen_px_from_ortho(
1139         const float uv[2],
1140         const float v1co[3], const float v2co[3], const float v3co[3],  /* Screenspace coords */
1141         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1142         float pixelScreenCo[4],
1143         float w[3])
1144 {
1145         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1146         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1147 }
1148
1149 /* same as screen_px_from_ortho except we
1150  * do perspective correction on the pixel coordinate */
1151 static void screen_px_from_persp(
1152         const float uv[2],
1153         const float v1co[4], const float v2co[4], const float v3co[4],  /* screenspace coords */
1154         const float uv1co[2], const float uv2co[2], const float uv3co[2],
1155         float pixelScreenCo[4],
1156         float w[3])
1157 {
1158         float w_int[3];
1159         float wtot_inv, wtot;
1160         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1161
1162         /* re-weight from the 4th coord of each screen vert */
1163         w_int[0] = w[0] * v1co[3];
1164         w_int[1] = w[1] * v2co[3];
1165         w_int[2] = w[2] * v3co[3];
1166
1167         wtot = w_int[0] + w_int[1] + w_int[2];
1168
1169         if (wtot > 0.0f) {
1170                 wtot_inv = 1.0f / wtot;
1171                 w_int[0] *= wtot_inv;
1172                 w_int[1] *= wtot_inv;
1173                 w_int[2] *= wtot_inv;
1174         }
1175         else {
1176                 w[0] = w[1] = w[2] =
1177                 w_int[0] = w_int[1] = w_int[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1178         }
1179         /* done re-weighting */
1180
1181         /* do interpolation based on projected weight */
1182         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w_int);
1183 }
1184
1185
1186 static void project_face_pixel(const MTFace *tf_other, ImBuf *ibuf_other, const float w[3],
1187                                int side, unsigned char rgba_ub[4], float rgba_f[4])
1188 {
1189         const float *uvCo1, *uvCo2, *uvCo3;
1190         float uv_other[2], x, y;
1191
1192         uvCo1 =  (float *)tf_other->uv[0];
1193         if (side == 1) {
1194                 uvCo2 =  (float *)tf_other->uv[2];
1195                 uvCo3 =  (float *)tf_other->uv[3];
1196         }
1197         else {
1198                 uvCo2 =  (float *)tf_other->uv[1];
1199                 uvCo3 =  (float *)tf_other->uv[2];
1200         }
1201
1202         interp_v2_v2v2v2(uv_other, uvCo1, uvCo2, uvCo3, (float *)w);
1203
1204         /* use */
1205         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1206
1207
1208         if (ibuf_other->rect_float) { /* from float to float */
1209                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1210         }
1211         else { /* from char to float */
1212                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1213         }
1214
1215 }
1216
1217 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1218 static float project_paint_uvpixel_mask(
1219         const ProjPaintState *ps,
1220         const int face_index,
1221         const int side,
1222         const float w[3])
1223 {
1224         float mask;
1225
1226         /* Image Mask */
1227         if (ps->do_layer_stencil) {
1228                 /* another UV maps image is masking this one's */
1229                 ImBuf *ibuf_other;
1230                 Image *other_tpage = ps->stencil_ima;
1231                 const MTFace *tf_other = ps->dm_mtface_stencil + face_index;
1232
1233                 if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1234                         /* BKE_image_acquire_ibuf - TODO - this may be slow */
1235                         unsigned char rgba_ub[4];
1236                         float rgba_f[4];
1237
1238                         project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, rgba_f);
1239
1240                         if (ibuf_other->rect_float) { /* from float to float */
1241                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) * (1.0f / 3.0f)) * rgba_f[3];
1242                         }
1243                         else { /* from char to float */
1244                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) * (1.0f / (255.0f * 3.0f))) * (rgba_ub[3] * (1.0f / 255.0f));
1245                         }
1246
1247                         BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1248
1249                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1250                                 mask = (1.0f - mask);
1251
1252                         if (mask == 0.0f) {
1253                                 return 0.0f;
1254                         }
1255                 }
1256                 else {
1257                         return 0.0f;
1258                 }
1259         }
1260         else {
1261                 mask = 1.0f;
1262         }
1263
1264         /* calculate mask */
1265         if (ps->do_mask_normal) {
1266                 MFace *mf = &ps->dm_mface[face_index];
1267                 float no[3], angle;
1268                 if (mf->flag & ME_SMOOTH) {
1269                         const short *no1, *no2, *no3;
1270                         no1 = ps->dm_mvert[mf->v1].no;
1271                         if (side == 1) {
1272                                 no2 = ps->dm_mvert[mf->v3].no;
1273                                 no3 = ps->dm_mvert[mf->v4].no;
1274                         }
1275                         else {
1276                                 no2 = ps->dm_mvert[mf->v2].no;
1277                                 no3 = ps->dm_mvert[mf->v3].no;
1278                         }
1279
1280                         no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1281                         no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1282                         no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1283                         normalize_v3(no);
1284                 }
1285                 else {
1286                         /* incase the */
1287 #if 1
1288                         /* normalizing per pixel isn't optimal, we could cache or check ps->*/
1289                         if (mf->v4)
1290                                 normal_quad_v3(no,
1291                                                ps->dm_mvert[mf->v1].co,
1292                                                ps->dm_mvert[mf->v2].co,
1293                                                ps->dm_mvert[mf->v3].co,
1294                                                ps->dm_mvert[mf->v4].co);
1295                         else
1296                                 normal_tri_v3(no,
1297                                               ps->dm_mvert[mf->v1].co,
1298                                               ps->dm_mvert[mf->v2].co,
1299                                               ps->dm_mvert[mf->v3].co);
1300 #else
1301                         /* don't use because some modifiers dont have normal data (subsurf for eg) */
1302                         copy_v3_v3(no, (float *)ps->dm->getTessFaceData(ps->dm, face_index, CD_NORMAL));
1303 #endif
1304                 }
1305
1306                 /* now we can use the normal as a mask */
1307                 if (ps->is_ortho) {
1308                         angle = angle_normalized_v3v3((float *)ps->viewDir, no);
1309                 }
1310                 else {
1311                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1312                         float viewDirPersp[3];
1313                         const float *co1, *co2, *co3;
1314                         co1 = ps->dm_mvert[mf->v1].co;
1315                         if (side == 1) {
1316                                 co2 = ps->dm_mvert[mf->v3].co;
1317                                 co3 = ps->dm_mvert[mf->v4].co;
1318                         }
1319                         else {
1320                                 co2 = ps->dm_mvert[mf->v2].co;
1321                                 co3 = ps->dm_mvert[mf->v3].co;
1322                         }
1323
1324                         /* Get the direction from the viewPoint to the pixel and normalize */
1325                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1326                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1327                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1328                         normalize_v3(viewDirPersp);
1329
1330                         angle = angle_normalized_v3v3(viewDirPersp, no);
1331                 }
1332
1333                 if (angle >= ps->normal_angle) {
1334                         return 0.0f; /* outsize the normal limit*/
1335                 }
1336                 else if (angle > ps->normal_angle_inner) {
1337                         mask *= (ps->normal_angle - angle) / ps->normal_angle_range;
1338                 } /* otherwise no mask normal is needed, were within the limit */
1339         }
1340
1341         /* This only works when the opacity dosnt change while painting, stylus pressure messes with this
1342          * so don't use it. */
1343         // if (ps->is_airbrush == 0) mask *= BKE_brush_alpha_get(ps->brush);
1344
1345         return mask;
1346 }
1347
1348 static int project_paint_pixel_sizeof(const short tool)
1349 {
1350         if ((tool == PAINT_TOOL_CLONE) || (tool == PAINT_TOOL_SMEAR)) {
1351                 return sizeof(ProjPixelClone);
1352         }
1353         else {
1354                 return sizeof(ProjPixel);
1355         }
1356 }
1357
1358 static int project_paint_undo_subtiles(const TileInfo *tinf, int tx, int ty)
1359 {
1360         ProjPaintImage *pjIma = tinf->pjima;
1361         int tile_index = tx + ty * tinf->tile_width;
1362         bool generate_tile = false;
1363
1364         /* double check lock to avoid locking */
1365         if (UNLIKELY(!pjIma->undoRect[tile_index])) {
1366                 if (tinf->lock)
1367                         BLI_spin_lock(tinf->lock);
1368                 if (LIKELY(!pjIma->undoRect[tile_index])) {
1369                         pjIma->undoRect[tile_index] = TILE_PENDING;
1370                         generate_tile = true;
1371                 }
1372                 if (tinf->lock)
1373                         BLI_spin_unlock(tinf->lock);
1374         }
1375
1376
1377         if (generate_tile) {
1378                 volatile void *undorect;
1379                 if (tinf->masked) {
1380                         undorect = image_undo_push_tile(pjIma->ima, pjIma->ibuf, tinf->tmpibuf, tx, ty, &pjIma->maskRect[tile_index], &pjIma->valid[tile_index], true);
1381                 }
1382                 else {
1383                         undorect = image_undo_push_tile(pjIma->ima, pjIma->ibuf, tinf->tmpibuf, tx, ty, NULL, &pjIma->valid[tile_index], true);
1384                 }
1385
1386                 pjIma->ibuf->userflags |= IB_BITMAPDIRTY;
1387                 /* tile ready, publish */
1388                 if (tinf->lock)
1389                         BLI_spin_lock(tinf->lock);
1390                 pjIma->undoRect[tile_index] = undorect;
1391                 if (tinf->lock)
1392                         BLI_spin_unlock(tinf->lock);
1393
1394         }
1395
1396         return tile_index;
1397 }
1398
1399 /* run this function when we know a bucket's, face's pixel can be initialized,
1400  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1401 static ProjPixel *project_paint_uvpixel_init(
1402         const ProjPaintState *ps,
1403         MemArena *arena,
1404         const TileInfo *tinf,
1405         int x_px, int y_px,
1406         const float mask,
1407         const int face_index,
1408         const float pixelScreenCo[4],
1409         const float world_spaceCo[3],
1410         const int side,
1411         const float w[3])
1412 {
1413         ProjPixel *projPixel;
1414         int x_tile, y_tile;
1415         int x_round, y_round;
1416         int tile_offset;
1417         /* volatile is important here to ensure pending check is not optimized away by compiler*/
1418         volatile int tile_index;
1419
1420         ProjPaintImage *projima = tinf->pjima;
1421         ImBuf *ibuf = projima->ibuf;
1422         /* wrap pixel location */
1423
1424         x_px = mod_i(x_px, ibuf->x);
1425         y_px = mod_i(y_px, ibuf->y);
1426
1427         BLI_assert(ps->pixel_sizeof == project_paint_pixel_sizeof(ps->tool));
1428         projPixel = (ProjPixel *)BLI_memarena_alloc(arena, ps->pixel_sizeof);
1429
1430         /* calculate the undo tile offset of the pixel, used to store the original
1431          * pixel color and accumulated mask if any */
1432         x_tile =  x_px >> IMAPAINT_TILE_BITS;
1433         y_tile =  y_px >> IMAPAINT_TILE_BITS;
1434
1435         x_round = x_tile * IMAPAINT_TILE_SIZE;
1436         y_round = y_tile * IMAPAINT_TILE_SIZE;
1437         //memset(projPixel, 0, size);
1438
1439         tile_offset = (x_px - x_round) + (y_px - y_round) * IMAPAINT_TILE_SIZE;
1440         tile_index = project_paint_undo_subtiles(tinf, x_tile, y_tile);
1441
1442         /* other thread may be initializing the tile so wait here */
1443         while (projima->undoRect[tile_index] == TILE_PENDING)
1444                 ;
1445
1446         BLI_assert(tile_index < (IMAPAINT_TILE_NUMBER(ibuf->x) * IMAPAINT_TILE_NUMBER(ibuf->y)));
1447         BLI_assert(tile_offset < (IMAPAINT_TILE_SIZE * IMAPAINT_TILE_SIZE));
1448
1449         projPixel->valid = projima->valid[tile_index];
1450
1451         if (ibuf->rect_float) {
1452                 projPixel->pixel.f_pt = ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1453                 projPixel->origColor.f_pt = (float *)projima->undoRect[tile_index] + 4 * tile_offset;
1454                 zero_v4(projPixel->newColor.f);
1455         }
1456         else {
1457                 projPixel->pixel.ch_pt = (unsigned char *)(ibuf->rect + (x_px + y_px * ibuf->x));
1458                 projPixel->origColor.uint_pt = (unsigned int *)projima->undoRect[tile_index] + tile_offset;
1459                 projPixel->newColor.uint = 0;
1460         }
1461
1462         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1463         if (ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D) {
1464                 copy_v3_v3(projPixel->worldCoSS, world_spaceCo);
1465         }
1466
1467         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1468
1469         projPixel->x_px = x_px;
1470         projPixel->y_px = y_px;
1471
1472         projPixel->mask = (unsigned short)(mask * 65535);
1473         if (ps->do_masking)
1474                 projPixel->mask_accum = projima->maskRect[tile_index] + tile_offset;
1475         else
1476                 projPixel->mask_accum = NULL;
1477
1478         /* which bounding box cell are we in?, needed for undo */
1479         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1480                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1481
1482         /* done with view3d_project_float inline */
1483         if (ps->tool == PAINT_TOOL_CLONE) {
1484                 if (ps->dm_mtface_clone) {
1485                         ImBuf *ibuf_other;
1486                         Image *other_tpage = project_paint_face_clone_image(ps, face_index);
1487                         const MTFace *tf_other = ps->dm_mtface_clone[face_index];
1488
1489                         if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1490                                 /* BKE_image_acquire_ibuf - TODO - this may be slow */
1491
1492                                 if (ibuf->rect_float) {
1493                                         if (ibuf_other->rect_float) { /* from float to float */
1494                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1495                                         }
1496                                         else { /* from char to float */
1497                                                 unsigned char rgba_ub[4];
1498                                                 float rgba[4];
1499                                                 project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, NULL);
1500                                                 srgb_to_linearrgb_uchar4(rgba, rgba_ub);
1501                                                 straight_to_premul_v4_v4(((ProjPixelClone *)projPixel)->clonepx.f, rgba);
1502                                         }
1503                                 }
1504                                 else {
1505                                         if (ibuf_other->rect_float) { /* float to char */
1506                                                 float rgba[4];
1507                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, rgba);
1508                                                 premul_to_straight_v4(rgba);
1509                                                 linearrgb_to_srgb_uchar3(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1510                                         }
1511                                         else { /* char to char */
1512                                                 project_face_pixel(tf_other, ibuf_other, w, side, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1513                                         }
1514                                 }
1515
1516                                 BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1517                         }
1518                         else {
1519                                 if (ibuf->rect_float) {
1520                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1521                                 }
1522                                 else {
1523                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1524                                 }
1525                         }
1526
1527                 }
1528                 else {
1529                         float co[2];
1530                         sub_v2_v2v2(co, projPixel->projCoSS, (float *)ps->cloneOffset);
1531
1532                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1533                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1534                         if (ibuf->rect_float) {
1535                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1536                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1537                                 }
1538                         }
1539                         else {
1540                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1541                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1542                                 }
1543                         }
1544                 }
1545         }
1546
1547 #ifdef PROJ_DEBUG_PAINT
1548         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1549         else                  projPixel->pixel.ch_pt[0] = 0;
1550 #endif
1551         /* pointer arithmetics */
1552         projPixel->image_index = projima - ps->projImages;
1553
1554         return projPixel;
1555 }
1556
1557 static bool line_clip_rect2f(
1558         rctf *rect,
1559         const float l1[2], const float l2[2],
1560         float l1_clip[2], float l2_clip[2])
1561 {
1562         /* first account for horizontal, then vertical lines */
1563         /* horiz */
1564         if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) {
1565                 /* is the line out of range on its Y axis? */
1566                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1567                         return 0;
1568                 }
1569                 /* line is out of range on its X axis */
1570                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1571                         return 0;
1572                 }
1573
1574
1575                 if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1576                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1577                                 copy_v2_v2(l1_clip, l1);
1578                                 copy_v2_v2(l2_clip, l2);
1579                                 return 1;
1580                         }
1581                         else {
1582                                 return 0;
1583                         }
1584                 }
1585
1586                 copy_v2_v2(l1_clip, l1);
1587                 copy_v2_v2(l2_clip, l2);
1588                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1589                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1590                 return 1;
1591         }
1592         else if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) {
1593                 /* is the line out of range on its X axis? */
1594                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1595                         return 0;
1596                 }
1597
1598                 /* line is out of range on its Y axis */
1599                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1600                         return 0;
1601                 }
1602
1603                 if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1604                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1605                                 copy_v2_v2(l1_clip, l1);
1606                                 copy_v2_v2(l2_clip, l2);
1607                                 return 1;
1608                         }
1609                         else {
1610                                 return 0;
1611                         }
1612                 }
1613
1614                 copy_v2_v2(l1_clip, l1);
1615                 copy_v2_v2(l2_clip, l2);
1616                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1617                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1618                 return 1;
1619         }
1620         else {
1621                 float isect;
1622                 short ok1 = 0;
1623                 short ok2 = 0;
1624
1625                 /* Done with vertical lines */
1626
1627                 /* are either of the points inside the rectangle ? */
1628                 if (BLI_rctf_isect_pt_v(rect, l1)) {
1629                         copy_v2_v2(l1_clip, l1);
1630                         ok1 = 1;
1631                 }
1632
1633                 if (BLI_rctf_isect_pt_v(rect, l2)) {
1634                         copy_v2_v2(l2_clip, l2);
1635                         ok2 = 1;
1636                 }
1637
1638                 /* line inside rect */
1639                 if (ok1 && ok2) return 1;
1640
1641                 /* top/bottom */
1642                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1643                         if (l1[1] < l2[1]) { /* line 1 is outside */
1644                                 l1_clip[0] = isect;
1645                                 l1_clip[1] = rect->ymin;
1646                                 ok1 = 1;
1647                         }
1648                         else {
1649                                 l2_clip[0] = isect;
1650                                 l2_clip[1] = rect->ymin;
1651                                 ok2 = 2;
1652                         }
1653                 }
1654
1655                 if (ok1 && ok2) return 1;
1656
1657                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1658                         if (l1[1] > l2[1]) { /* line 1 is outside */
1659                                 l1_clip[0] = isect;
1660                                 l1_clip[1] = rect->ymax;
1661                                 ok1 = 1;
1662                         }
1663                         else {
1664                                 l2_clip[0] = isect;
1665                                 l2_clip[1] = rect->ymax;
1666                                 ok2 = 2;
1667                         }
1668                 }
1669
1670                 if (ok1 && ok2) return 1;
1671
1672                 /* left/right */
1673                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1674                         if (l1[0] < l2[0]) { /* line 1 is outside */
1675                                 l1_clip[0] = rect->xmin;
1676                                 l1_clip[1] = isect;
1677                                 ok1 = 1;
1678                         }
1679                         else {
1680                                 l2_clip[0] = rect->xmin;
1681                                 l2_clip[1] = isect;
1682                                 ok2 = 2;
1683                         }
1684                 }
1685
1686                 if (ok1 && ok2) return 1;
1687
1688                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1689                         if (l1[0] > l2[0]) { /* line 1 is outside */
1690                                 l1_clip[0] = rect->xmax;
1691                                 l1_clip[1] = isect;
1692                                 ok1 = 1;
1693                         }
1694                         else {
1695                                 l2_clip[0] = rect->xmax;
1696                                 l2_clip[1] = isect;
1697                                 ok2 = 2;
1698                         }
1699                 }
1700
1701                 if (ok1 && ok2) {
1702                         return 1;
1703                 }
1704                 else {
1705                         return 0;
1706                 }
1707         }
1708 }
1709
1710
1711
1712 /* scale the quad & tri about its center
1713  * scaling by PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1714  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces */
1715 #ifndef PROJ_DEBUG_NOSEAMBLEED
1716 static void scale_quad(float insetCos[4][3], float *origCos[4], const float inset)
1717 {
1718         float cent[3];
1719         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0] + origCos[3][0]) * (1.0f / 4.0f);
1720         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1] + origCos[3][1]) * (1.0f / 4.0f);
1721         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2] + origCos[3][2]) * (1.0f / 4.0f);
1722
1723         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1724         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1725         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1726         sub_v3_v3v3(insetCos[3], origCos[3], cent);
1727
1728         mul_v3_fl(insetCos[0], inset);
1729         mul_v3_fl(insetCos[1], inset);
1730         mul_v3_fl(insetCos[2], inset);
1731         mul_v3_fl(insetCos[3], inset);
1732
1733         add_v3_v3(insetCos[0], cent);
1734         add_v3_v3(insetCos[1], cent);
1735         add_v3_v3(insetCos[2], cent);
1736         add_v3_v3(insetCos[3], cent);
1737 }
1738
1739
1740 static void scale_tri(float insetCos[4][3], float *origCos[4], const float inset)
1741 {
1742         float cent[3];
1743         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) * (1.0f / 3.0f);
1744         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) * (1.0f / 3.0f);
1745         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) * (1.0f / 3.0f);
1746
1747         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1748         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1749         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1750
1751         mul_v3_fl(insetCos[0], inset);
1752         mul_v3_fl(insetCos[1], inset);
1753         mul_v3_fl(insetCos[2], inset);
1754
1755         add_v3_v3(insetCos[0], cent);
1756         add_v3_v3(insetCos[1], cent);
1757         add_v3_v3(insetCos[2], cent);
1758 }
1759 #endif //PROJ_DEBUG_NOSEAMBLEED
1760
1761 static float len_squared_v2v2_alt(const float v1[2], const float v2_1, const float v2_2)
1762 {
1763         float x, y;
1764
1765         x = v1[0] - v2_1;
1766         y = v1[1] - v2_2;
1767         return x * x + y * y;
1768 }
1769
1770 /* note, use a squared value so we can use len_squared_v2v2
1771  * be sure that you have done a bounds check first or this may fail */
1772 /* only give bucket_bounds as an arg because we need it elsewhere */
1773 static bool project_bucket_isect_circle(const float cent[2], const float radius_squared, rctf *bucket_bounds)
1774 {
1775
1776         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect
1777          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1778          * this is even less work then an intersection test
1779          */
1780 #if 0
1781         if (BLI_rctf_isect_pt_v(bucket_bounds, cent))
1782                 return 1;
1783 #endif
1784
1785         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1786             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1787         {
1788                 return 1;
1789         }
1790
1791         /* out of bounds left */
1792         if (cent[0] < bucket_bounds->xmin) {
1793                 /* lower left out of radius test */
1794                 if (cent[1] < bucket_bounds->ymin) {
1795                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1796                 }
1797                 /* top left test */
1798                 else if (cent[1] > bucket_bounds->ymax) {
1799                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1800                 }
1801         }
1802         else if (cent[0] > bucket_bounds->xmax) {
1803                 /* lower right out of radius test */
1804                 if (cent[1] < bucket_bounds->ymin) {
1805                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1806                 }
1807                 /* top right test */
1808                 else if (cent[1] > bucket_bounds->ymax) {
1809                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1810                 }
1811         }
1812
1813         return 0;
1814 }
1815
1816
1817
1818 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1819  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1820  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1821  * (viewed from the side)
1822  *
1823  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1824  * funcs that only account for points inside the triangle.
1825  * however switching back to this for ortho is always an option */
1826
1827 static void rect_to_uvspace_ortho(
1828         rctf *bucket_bounds,
1829         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1830         const float *uv1co, const float *uv2co, const float *uv3co,
1831         float bucket_bounds_uv[4][2],
1832         const int flip)
1833 {
1834         float uv[2];
1835         float w[3];
1836
1837         /* get the UV space bounding box */
1838         uv[0] = bucket_bounds->xmax;
1839         uv[1] = bucket_bounds->ymin;
1840         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1841         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1842
1843         //uv[0] = bucket_bounds->xmax; // set above
1844         uv[1] = bucket_bounds->ymax;
1845         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1846         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1847
1848         uv[0] = bucket_bounds->xmin;
1849         //uv[1] = bucket_bounds->ymax; // set above
1850         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1851         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1852
1853         //uv[0] = bucket_bounds->xmin; // set above
1854         uv[1] = bucket_bounds->ymin;
1855         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1856         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1857 }
1858
1859 /* same as above but use barycentric_weights_v2_persp */
1860 static void rect_to_uvspace_persp(
1861         rctf *bucket_bounds,
1862         const float *v1coSS, const float *v2coSS, const float *v3coSS,
1863         const float *uv1co, const float *uv2co, const float *uv3co,
1864         float bucket_bounds_uv[4][2],
1865         const int flip
1866         )
1867 {
1868         float uv[2];
1869         float w[3];
1870
1871         /* get the UV space bounding box */
1872         uv[0] = bucket_bounds->xmax;
1873         uv[1] = bucket_bounds->ymin;
1874         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1875         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1876
1877         //uv[0] = bucket_bounds->xmax; // set above
1878         uv[1] = bucket_bounds->ymax;
1879         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1880         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1881
1882         uv[0] = bucket_bounds->xmin;
1883         //uv[1] = bucket_bounds->ymax; // set above
1884         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1885         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1886
1887         //uv[0] = bucket_bounds->xmin; // set above
1888         uv[1] = bucket_bounds->ymin;
1889         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1890         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1891 }
1892
1893 /* This works as we need it to but we can save a few steps and not use it */
1894
1895 #if 0
1896 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
1897 {
1898         float v1[2], v2[2];
1899
1900         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
1901         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
1902
1903         return -atan2(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
1904 }
1905 #endif
1906
1907 #define ISECT_1 (1)
1908 #define ISECT_2 (1 << 1)
1909 #define ISECT_3 (1 << 2)
1910 #define ISECT_4 (1 << 3)
1911 #define ISECT_ALL3 ((1 << 3) - 1)
1912 #define ISECT_ALL4 ((1 << 4) - 1)
1913
1914 /* limit must be a fraction over 1.0f */
1915 static bool IsectPT2Df_limit(float pt[2], float v1[2], float v2[2], float v3[2], float limit)
1916 {
1917         return ((area_tri_v2(pt, v1, v2) +
1918                  area_tri_v2(pt, v2, v3) +
1919                  area_tri_v2(pt, v3, v1)) / (area_tri_v2(v1, v2, v3))) < limit;
1920 }
1921
1922 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
1923  * so we have the clipped UV's to do pixel intersection tests with
1924  * */
1925 static int float_z_sort_flip(const void *p1, const void *p2)
1926 {
1927         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
1928 }
1929
1930 static int float_z_sort(const void *p1, const void *p2)
1931 {
1932         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
1933 }
1934
1935 static void project_bucket_clip_face(
1936         const bool is_ortho,
1937         rctf *bucket_bounds,
1938         float *v1coSS, float *v2coSS, float *v3coSS,
1939         const float *uv1co, const float *uv2co, const float *uv3co,
1940         float bucket_bounds_uv[8][2],
1941         int *tot)
1942 {
1943         int inside_bucket_flag = 0;
1944         int inside_face_flag = 0;
1945         const int flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
1946
1947         float bucket_bounds_ss[4][2];
1948
1949         /* get the UV space bounding box */
1950         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v1coSS);
1951         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v2coSS) << 1;
1952         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v3coSS) << 2;
1953
1954         if (inside_bucket_flag == ISECT_ALL3) {
1955                 /* all screenspace points are inside the bucket bounding box, this means we don't need to clip and can simply return the UVs */
1956                 if (flip) { /* facing the back? */
1957                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
1958                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1959                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
1960                 }
1961                 else {
1962                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
1963                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1964                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
1965                 }
1966
1967                 *tot = 3;
1968                 return;
1969         }
1970
1971         /* get the UV space bounding box */
1972         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
1973         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
1974         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
1975         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
1976
1977         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
1978         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
1979         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
1980
1981         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
1982         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
1983         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
1984
1985         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
1986         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
1987         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
1988
1989         if (inside_face_flag == ISECT_ALL4) {
1990                 /* bucket is totally inside the screenspace face, we can safely use weights */
1991
1992                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
1993                 else rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
1994
1995                 *tot = 4;
1996                 return;
1997         }
1998         else {
1999                 /* The Complicated Case!
2000                  *
2001                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
2002                  *
2003                  * we need to make a convex polyline from the intersection between the screenspace face
2004                  * and the bucket bounds.
2005                  *
2006                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
2007                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
2008                  * do a correct clipping on both shapes. */
2009
2010
2011                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
2012
2013
2014
2015                 /* Maximum possible 6 intersections when using a rectangle and triangle */
2016                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
2017                 float v1_clipSS[2], v2_clipSS[2];
2018                 float w[3];
2019
2020                 /* calc center */
2021                 float cent[2] = {0.0f, 0.0f};
2022                 /*float up[2] = {0.0f, 1.0f};*/
2023                 int i;
2024                 short doubles;
2025
2026                 (*tot) = 0;
2027
2028                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
2029                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
2030                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
2031                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
2032
2033                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
2034                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
2035                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
2036
2037                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
2038                         if (line_clip_rect2f(bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
2039                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2040                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2041                         }
2042                 }
2043
2044                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
2045                         if (line_clip_rect2f(bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
2046                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2047                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2048                         }
2049                 }
2050
2051                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
2052                         if (line_clip_rect2f(bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
2053                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
2054                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
2055                         }
2056                 }
2057
2058
2059                 if ((*tot) < 3) { /* no intersections to speak of */
2060                         *tot = 0;
2061                         return;
2062                 }
2063
2064                 /* now we have all points we need, collect their angles and sort them clockwise */
2065
2066                 for (i = 0; i < (*tot); i++) {
2067                         cent[0] += isectVCosSS[i][0];
2068                         cent[1] += isectVCosSS[i][1];
2069                 }
2070                 cent[0] = cent[0] / (float)(*tot);
2071                 cent[1] = cent[1] / (float)(*tot);
2072
2073
2074
2075                 /* Collect angles for every point around the center point */
2076
2077
2078 #if 0   /* uses a few more cycles then the above loop */
2079                 for (i = 0; i < (*tot); i++) {
2080                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
2081                 }
2082 #endif
2083
2084                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
2085                 v1_clipSS[1] = cent[1] + 1.0f;
2086
2087                 for (i = 0; i < (*tot); i++) {
2088                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2089                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2090                         isectVCosSS[i][2] = atan2f(v1_clipSS[0] * v2_clipSS[1] - v1_clipSS[1] * v2_clipSS[0], v1_clipSS[0] * v2_clipSS[0] + v1_clipSS[1] * v2_clipSS[1]);
2091                 }
2092
2093                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
2094                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
2095
2096                 /* remove doubles */
2097                 /* first/last check */
2098                 if (fabsf(isectVCosSS[0][0] - isectVCosSS[(*tot) - 1][0]) < PROJ_PIXEL_TOLERANCE &&
2099                     fabsf(isectVCosSS[0][1] - isectVCosSS[(*tot) - 1][1]) < PROJ_PIXEL_TOLERANCE)
2100                 {
2101                         (*tot)--;
2102                 }
2103
2104                 /* its possible there is only a few left after remove doubles */
2105                 if ((*tot) < 3) {
2106                         // printf("removed too many doubles A\n");
2107                         *tot = 0;
2108                         return;
2109                 }
2110
2111                 doubles = true;
2112                 while (doubles == true) {
2113                         doubles = false;
2114                         for (i = 1; i < (*tot); i++) {
2115                                 if (fabsf(isectVCosSS[i - 1][0] - isectVCosSS[i][0]) < PROJ_PIXEL_TOLERANCE &&
2116                                     fabsf(isectVCosSS[i - 1][1] - isectVCosSS[i][1]) < PROJ_PIXEL_TOLERANCE)
2117                                 {
2118                                         int j;
2119                                         for (j = i + 1; j < (*tot); j++) {
2120                                                 isectVCosSS[j - 1][0] = isectVCosSS[j][0];
2121                                                 isectVCosSS[j - 1][1] = isectVCosSS[j][1];
2122                                         }
2123                                         doubles = true; /* keep looking for more doubles */
2124                                         (*tot)--;
2125                                 }
2126                         }
2127                 }
2128
2129                 /* its possible there is only a few left after remove doubles */
2130                 if ((*tot) < 3) {
2131                         // printf("removed too many doubles B\n");
2132                         *tot = 0;
2133                         return;
2134                 }
2135
2136
2137                 if (is_ortho) {
2138                         for (i = 0; i < (*tot); i++) {
2139                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2140                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2141                         }
2142                 }
2143                 else {
2144                         for (i = 0; i < (*tot); i++) {
2145                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2146                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2147                         }
2148                 }
2149         }
2150
2151 #ifdef PROJ_DEBUG_PRINT_CLIP
2152         /* include this at the bottom of the above function to debug the output */
2153
2154         {
2155                 /* If there are ever any problems, */
2156                 float test_uv[4][2];
2157                 int i;
2158                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2159                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2160                 printf("(  [(%f,%f), (%f,%f), (%f,%f), (%f,%f)], ", test_uv[0][0], test_uv[0][1],   test_uv[1][0], test_uv[1][1],    test_uv[2][0], test_uv[2][1],    test_uv[3][0], test_uv[3][1]);
2161
2162                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2163
2164                 printf("[");
2165                 for (i = 0; i < (*tot); i++) {
2166                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2167                 }
2168                 printf("]),\\\n");
2169         }
2170 #endif
2171 }
2172
2173 /*
2174  * # This script creates faces in a blender scene from printed data above.
2175  *
2176  * project_ls = [
2177  * ...(output from above block)...
2178  * ]
2179  *
2180  * from Blender import Scene, Mesh, Window, sys, Mathutils
2181  *
2182  * import bpy
2183  *
2184  * V = Mathutils.Vector
2185  *
2186  * def main():
2187  *     sce = bpy.data.scenes.active
2188  *
2189  *     for item in project_ls:
2190  *         bb = item[0]
2191  *         uv = item[1]
2192  *         poly = item[2]
2193  *
2194  *         me = bpy.data.meshes.new()
2195  *         ob = sce.objects.new(me)
2196  *
2197  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2198  *         me.faces.extend([(0,1,2,3),])
2199  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2200  *         me.faces.extend([(4,5,6),])
2201  *
2202  *         vs = [V(p).xyz for p in poly]
2203  *         print len(vs)
2204  *         l = len(me.verts)
2205  *         me.verts.extend(vs)
2206  *
2207  *         i = l
2208  *         while i < len(me.verts):
2209  *             ii = i + 1
2210  *             if ii == len(me.verts):
2211  *                 ii = l
2212  *             me.edges.extend([i, ii])
2213  *             i += 1
2214  *
2215  * if __name__ == '__main__':
2216  *     main()
2217  */
2218
2219
2220 #undef ISECT_1
2221 #undef ISECT_2
2222 #undef ISECT_3
2223 #undef ISECT_4
2224 #undef ISECT_ALL3
2225 #undef ISECT_ALL4
2226
2227
2228 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2229  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2230 static bool IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2231 {
2232         int i;
2233         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2234                 return 0;
2235
2236         for (i = 1; i < tot; i++) {
2237                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2238                         return 0;
2239
2240         }
2241
2242         return 1;
2243 }
2244 static bool IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2245 {
2246         int i;
2247         int side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2248
2249         for (i = 1; i < tot; i++) {
2250                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2251                         return 0;
2252
2253         }
2254
2255         return 1;
2256 }
2257
2258 /* One of the most important function for projection painting, since it selects the pixels to be added into each bucket.
2259  * initialize pixels from this face where it intersects with the bucket_index, optionally initialize pixels for removing seams */
2260 static void project_paint_face_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, const int face_index, const int image_index, rctf *bucket_bounds, ImBuf *ibuf, ImBuf **tmpibuf, const short clamp_u, const short clamp_v)
2261 {
2262         /* Projection vars, to get the 3D locations into screen space  */
2263         MemArena *arena = ps->arena_mt[thread_index];
2264         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2265         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2266         bool threaded = (ps->thread_tot > 1);
2267
2268         TileInfo tinf = {
2269                 ps->tile_lock,
2270                 ps->do_masking,
2271                 IMAPAINT_TILE_NUMBER(ibuf->x),
2272                 tmpibuf,
2273                 ps->projImages + image_index
2274         };
2275
2276         const MFace *mf = ps->dm_mface + face_index;
2277         const MTFace *tf = ps->dm_mtface[face_index];
2278
2279         /* UV/pixel seeking data */
2280         int x; /* Image X-Pixel */
2281         int y; /* Image Y-Pixel */
2282         float mask;
2283         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2284
2285         int side;
2286         float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to mf->v1,2,3 or mf->v1,3,4 */
2287
2288         float *vCo[4]; /* vertex screenspace coords */
2289
2290         float w[3], wco[3];
2291
2292         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to tf->uv[0],1,2 or tf->uv[0],2,3 */
2293         float pixelScreenCo[4];
2294         bool do_3d_mapping = ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D;
2295
2296         rcti bounds_px; /* ispace bounds */
2297         /* vars for getting uvspace bounds */
2298
2299         float tf_uv_pxoffset[4][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2300         float xhalfpx, yhalfpx;
2301         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2302
2303         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2304
2305         int i1, i2, i3;
2306
2307         float uv_clip[8][2];
2308         int uv_clip_tot;
2309         const bool is_ortho = ps->is_ortho;
2310         const bool do_backfacecull = ps->do_backfacecull;
2311         const bool do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2312
2313         vCo[0] = ps->dm_mvert[mf->v1].co;
2314         vCo[1] = ps->dm_mvert[mf->v2].co;
2315         vCo[2] = ps->dm_mvert[mf->v3].co;
2316
2317
2318         /* Use tf_uv_pxoffset instead of tf->uv so we can offset the UV half a pixel
2319          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2320          * problems when wrapping negative coords */
2321         xhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 3.0f))) / ibuf_xf;
2322         yhalfpx = (0.5f + (PROJ_PIXEL_TOLERANCE * (1.0f / 4.0f))) / ibuf_yf;
2323
2324         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2325          * Needed to add this offset since UV coords are often quads aligned to pixels.
2326          * In this case pixels can be exactly between 2 triangles causing nasty
2327          * artifacts.
2328          *
2329          * This workaround can be removed and painting will still work on most cases
2330          * but since the first thing most people try is painting onto a quad- better make it work.
2331          */
2332
2333         tf_uv_pxoffset[0][0] = tf->uv[0][0] - xhalfpx;
2334         tf_uv_pxoffset[0][1] = tf->uv[0][1] - yhalfpx;
2335
2336         tf_uv_pxoffset[1][0] = tf->uv[1][0] - xhalfpx;
2337         tf_uv_pxoffset[1][1] = tf->uv[1][1] - yhalfpx;
2338
2339         tf_uv_pxoffset[2][0] = tf->uv[2][0] - xhalfpx;
2340         tf_uv_pxoffset[2][1] = tf->uv[2][1] - yhalfpx;
2341
2342         if (mf->v4) {
2343                 vCo[3] = ps->dm_mvert[mf->v4].co;
2344
2345                 tf_uv_pxoffset[3][0] = tf->uv[3][0] - xhalfpx;
2346                 tf_uv_pxoffset[3][1] = tf->uv[3][1] - yhalfpx;
2347                 side = 1;
2348         }
2349         else {
2350                 side = 0;
2351         }
2352
2353         do {
2354                 if (side == 1) {
2355                         i1 = 0; i2 = 2; i3 = 3;
2356                 }
2357                 else {
2358                         i1 = 0; i2 = 1; i3 = 2;
2359                 }
2360
2361                 uv1co = tf_uv_pxoffset[i1]; // was tf->uv[i1];
2362                 uv2co = tf_uv_pxoffset[i2]; // was tf->uv[i2];
2363                 uv3co = tf_uv_pxoffset[i3]; // was tf->uv[i3];
2364
2365                 v1coSS = ps->screenCoords[(*(&mf->v1 + i1))];
2366                 v2coSS = ps->screenCoords[(*(&mf->v1 + i2))];
2367                 v3coSS = ps->screenCoords[(*(&mf->v1 + i3))];
2368
2369                 /* This funtion gives is a concave polyline in UV space from the clipped quad and tri*/
2370                 project_bucket_clip_face(
2371                         is_ortho, bucket_bounds,
2372                         v1coSS, v2coSS, v3coSS,
2373                         uv1co, uv2co, uv3co,
2374                         uv_clip, &uv_clip_tot
2375                         );
2376
2377                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2378 #if 0
2379                 if (uv_clip_tot > 6) {
2380                         printf("this should never happen! %d\n", uv_clip_tot);
2381                 }
2382 #endif
2383
2384                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2385
2386                         if (clamp_u) {
2387                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2388                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2389                         }
2390
2391                         if (clamp_v) {
2392                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2393                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2394                         }
2395
2396                         /*
2397                         project_paint_undo_tiles_init(&bounds_px, ps->projImages + image_index, tmpibuf,
2398                                                       tile_width, threaded, ps->do_masking);
2399                         */
2400                         /* clip face and */
2401
2402                         has_isect = 0;
2403                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2404                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2405                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2406
2407                                 has_x_isect = 0;
2408                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2409                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2410                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2411
2412                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2413                                          * could check the poly direction but better to do this */
2414                                         if ((do_backfacecull == true  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2415                                             (do_backfacecull == false && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2416                                         {
2417
2418                                                 has_x_isect = has_isect = 1;
2419
2420                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2421                                                 else screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2422
2423                                                 /* a pity we need to get the worldspace pixel location here */
2424                                                 if (do_clip || do_3d_mapping) {
2425                                                         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);
2426                                                         if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2427                                                                 continue; /* Watch out that no code below this needs to run */
2428                                                         }
2429                                                 }
2430
2431                                                 /* Is this UV visible from the view? - raytrace */
2432                                                 /* project_paint_PickFace is less complex, use for testing */
2433                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == face_index) {
2434                                                 if ((ps->do_occlude == false) ||
2435                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2436                                                 {
2437                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2438
2439                                                         if (mask > 0.0f) {
2440                                                                 BLI_linklist_prepend_arena(
2441                                                                         bucketPixelNodes,
2442                                                                         project_paint_uvpixel_init(ps, arena, &tinf, x, y, mask, face_index,
2443                                                                                                    pixelScreenCo, wco, side, w),
2444                                                                         arena
2445                                                                         );
2446                                                         }
2447                                                 }
2448
2449                                         }
2450 //#if 0
2451                                         else if (has_x_isect) {
2452                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2453                                                 break;
2454                                         }
2455 //#endif
2456                                 }
2457
2458
2459 #if 0           /* TODO - investigate why this dosnt work sometimes! it should! */
2460                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2461                                 if (has_x_isect == 0 && has_isect) {
2462                                         break;
2463                                 }
2464 #endif
2465                         }
2466                 }
2467         } while (side--);
2468
2469
2470
2471 #ifndef PROJ_DEBUG_NOSEAMBLEED
2472         if (ps->seam_bleed_px > 0.0f) {
2473                 int face_seam_flag;
2474
2475                 if (threaded)
2476                         BLI_lock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2477
2478                 face_seam_flag = ps->faceSeamFlags[face_index];
2479
2480                 /* are any of our edges un-initialized? */
2481                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_NOSEAM1)) == 0 ||
2482                     (face_seam_flag & (PROJ_FACE_SEAM2 | PROJ_FACE_NOSEAM2)) == 0 ||
2483                     (face_seam_flag & (PROJ_FACE_SEAM3 | PROJ_FACE_NOSEAM3)) == 0 ||
2484                     (face_seam_flag & (PROJ_FACE_SEAM4 | PROJ_FACE_NOSEAM4)) == 0)
2485                 {
2486                         project_face_seams_init(ps, face_index, mf->v4);
2487                         face_seam_flag = ps->faceSeamFlags[face_index];
2488                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3, flag&PROJ_FACE_SEAM4);
2489                 }
2490
2491                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_SEAM2 | PROJ_FACE_SEAM3 | PROJ_FACE_SEAM4)) == 0) {
2492
2493                         if (threaded)
2494                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2495
2496                 }
2497                 else {
2498                         /* we have a seam - deal with it! */
2499
2500                         /* Now create new UV's for the seam face */
2501                         float (*outset_uv)[2] = ps->faceSeamUVs[face_index];
2502                         float insetCos[4][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2503
2504                         float *vCoSS[4]; /* vertex screenspace coords */
2505
2506                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2507                         float edge_verts_inset_clip[2][3];
2508                         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 */
2509
2510                         float seam_subsection[4][2];
2511                         float fac1, fac2, ftot;
2512
2513
2514                         if (outset_uv[0][0] == FLT_MAX) /* first time initialize */
2515                                 uv_image_outset(tf_uv_pxoffset, outset_uv, ps->seam_bleed_px, ibuf->x, ibuf->y, mf->v4 != 0);
2516
2517                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2518                         if (threaded)
2519                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2520
2521                         vCoSS[0] = ps->screenCoords[mf->v1];
2522                         vCoSS[1] = ps->screenCoords[mf->v2];
2523                         vCoSS[2] = ps->screenCoords[mf->v3];
2524                         if (mf->v4)
2525                                 vCoSS[3] = ps->screenCoords[mf->v4];
2526
2527                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2528                         if (is_ortho) {
2529                                 if (mf->v4) scale_quad(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2530                                 else        scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2531                         }
2532                         else {
2533                                 if (mf->v4) scale_quad(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2534                                 else        scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2535                         }
2536
2537                         side = 0; /* for triangles this wont need to change */
2538
2539                         for (fidx1 = 0; fidx1 < (mf->v4 ? 4 : 3); fidx1++) {
2540                                 if (mf->v4) fidx2 = (fidx1 == 3) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2,3) -> (1,2,3,0) */
2541                                 else        fidx2 = (fidx1 == 2) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2) -> (1,2,0) */
2542
2543                                 if ((face_seam_flag & (1 << fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2544                                     line_clip_rect2f(bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1]))
2545                                 {
2546
2547                                         ftot = len_v2v2(vCoSS[fidx1], vCoSS[fidx2]); /* screenspace edge length */
2548
2549                                         if (ftot > 0.0f) { /* avoid div by zero */
2550                                                 if (mf->v4) {
2551                                                         if (fidx1 == 2 || fidx2 == 2) side = 1;
2552                                                         else side = 0;
2553                                                 }
2554
2555                                                 fac1 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[0]) / ftot;
2556                                                 fac2 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[1]) / ftot;
2557
2558                                                 interp_v2_v2v2(seam_subsection[0], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac1);
2559                                                 interp_v2_v2v2(seam_subsection[1], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac2);
2560
2561                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2562                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2563
2564                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2565                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2566                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2567                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2568
2569
2570                                                 if (pixel_bounds_uv(seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3], &bounds_px, ibuf->x, ibuf->y, true)) {
2571                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2572
2573                                                         has_isect = 0;
2574                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2575                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2576                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2577
2578                                                                 has_x_isect = 0;
2579                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2580                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2581                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2582
2583                                                                         /* test we're inside uvspace bucket and triangle bounds */
2584                                                                         if (isect_point_quad_v2(uv, seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3])) {
2585                                                                                 float fac;
2586
2587                                                                                 /* We need to find the closest point along the face edge,
2588                                                                                  * getting the screen_px_from_*** wont work because our actual location
2589                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2590                                                                                  * our location on the side of the face's UV */
2591 #if 0
2592                                                                                 if (is_ortho) screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2593                                                                                 else          screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2594 #endif
2595
2596                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2597                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2598
2599                                                                                 fac = line_point_factor_v2(uv, seam_subsection[0], seam_subsection[1]);
2600                                                                                 if      (fac < 0.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[0]); }
2601                                                                                 else if (fac > 1.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[1]); }
2602                                                                                 else                 { interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac); }
2603
2604                                                                                 if (!is_ortho) {
2605                                                                                         pixelScreenCo[3] = 1.0f;
2606                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2607                                                                                         pixelScreenCo[0] = (float)(ps->winx * 0.5f) + (ps->winx * 0.5f) * pixelScreenCo[0] / pixelScreenCo[3];
2608                                                                                         pixelScreenCo[1] = (float)(ps->winy * 0.5f) + (ps->winy * 0.5f) * pixelScreenCo[1] / pixelScreenCo[3];
2609                                                                                         pixelScreenCo[2] = pixelScreenCo[2] / pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2610                                                                                 }
2611
2612                                                                                 if ((ps->do_occlude == false) ||
2613                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2614                                                                                 {
2615                                                                                         /* Only bother calculating the weights if we intersect */
2616                                                                                         if (ps->do_mask_normal || ps->dm_mtface_clone) {
2617 #if 1
2618                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2619                                                                                                 float uv_close[2];
2620                                                                                                 float uv_fac = closest_to_line_v2(uv_close, uv, tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2]);
2621                                                                                                 if      (uv_fac < 0.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx1]);
2622                                                                                                 else if (uv_fac > 1.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx2]);
2623
2624                                                                                                 if (side) {
2625                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[2], tf_uv_pxoffset[3], uv_close, w);
2626                                                                                                 }
2627                                                                                                 else {
2628                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[1], tf_uv_pxoffset[2], uv_close, w);
2629                                                                                                 }
2630 #else                                                                                   /* this is buggy with quads, don't use for now */
2631
2632                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2633                                                                                                 uv_fac = fac1 + (uv_fac * (fac2 - fac1));
2634
2635                                                                                                 w[0] = w[1] = w[2] = 0.0;
2636                                                                                                 if (side) {
2637                                                                                                         w[fidx1 ? fidx1 - 1 : 0] = 1.0f - uv_fac;
2638                                                                                                         w[fidx2 ? fidx2 - 1 : 0] = uv_fac;
2639                                                                                                 }
2640                                                                                                 else {
2641                                                                                                         w[fidx1] = 1.0f - uv_fac;
2642                                                                                                         w[fidx2] = uv_fac;
2643                                                                                                 }
2644 #endif
2645                                                                                         }
2646
2647                                                                                         /* a pity we need to get the worldspace pixel location here */
2648                                                                                         if (do_clip || do_3d_mapping) {
2649                                                                                                 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);
2650                                                                                                 else      interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
2651
2652                                                                                                 if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, true)) {
2653                                                                                                         continue; /* Watch out that no code below this needs to run */
2654                                                                                                 }
2655                                                                                         }
2656
2657                                                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2658
2659                                                                                         if (mask > 0.0f) {
2660                                                                                                 BLI_linklist_prepend_arena(
2661                                                                                                         bucketPixelNodes,
2662                                                                                                         project_paint_uvpixel_init(ps, arena, &tinf, x, y, mask, face_index,
2663                                                                                                         pixelScreenCo, wco, side, w),
2664                                                                                                         arena
2665                                                                                                         );
2666                                                                                         }
2667
2668                                                                                 }
2669                                                                         }
2670                                                                         else if (has_x_isect) {
2671                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2672                                                                                 break;
2673                                                                         }
2674                                                                 }
2675
2676 #if 0                           /* TODO - investigate why this dosnt work sometimes! it should! */
2677                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2678                                                                 if (has_x_isect == 0 && has_isect) {
2679                                                                         break;
2680                                                                 }
2681 #endif
2682                                                         }
2683                                                 }
2684                                         }
2685                                 }
2686                         }
2687                 }
2688         }
2689 #endif // PROJ_DEBUG_NOSEAMBLEED
2690 }
2691
2692
2693 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2694 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2695 {
2696         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2697         /* XXX: the offset of 0.5 is always truncated to zero and the offset of 1.5f is always truncated to 1, is this really correct?? - jwilkins */
2698         bucketMin[0] = (int)((int)(((float)(min[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 0.5f); /* these offsets of 0.5 and 1.5 seem odd but they are correct */
2699         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2700
2701         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2702         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2703
2704         /* in case the rect is outside the mesh 2d bounds */
2705         CLAMP(bucketMin[0], 0, ps->buckets_x);
2706         CLAMP(bucketMin[1], 0, ps->buckets_y);
2707
2708         CLAMP(bucketMax[0], 0, ps->buckets_x);
2709         CLAMP(bucketMax[1], 0, ps->buckets_y);
2710 }
2711
2712 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2713 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2714 {
2715         bucket_bounds->xmin = ps->screenMin[0] + ((bucket_x) * (ps->screen_width / ps->buckets_x));     /* left */
2716         bucket_bounds->xmax = ps->screenMin[0] + ((bucket_x + 1) * (ps->screen_width / ps->buckets_x)); /* right */
2717
2718         bucket_bounds->ymin = ps->screenMin[1] + ((bucket_y) * (ps->screen_height / ps->buckets_y));      /* bottom */
2719         bucket_bounds->ymax = ps->screenMin[1] + ((bucket_y + 1) * (ps->screen_height  / ps->buckets_y)); /* top */
2720 }
2721
2722 /* Fill this bucket with pixels from the faces that intersect it.
2723  *
2724  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2725 static void project_bucket_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, rctf *bucket_bounds)
2726 {
2727         LinkNode *node;
2728         int face_index, image_index = 0;
2729         ImBuf *ibuf = NULL;
2730         Image *tpage_last = NULL, *tpage;
2731         Image *ima = NULL;
2732         ImBuf *tmpibuf = NULL;
2733
2734         if (ps->image_tot == 1) {
2735                 /* Simple loop, no context switching */
2736                 ibuf = ps->projImages[0].ibuf;
2737                 ima = ps->projImages[0].ima;
2738
2739                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2740                         project_paint_face_init(ps, thread_index, bucket_index, GET_INT_FROM_POINTER(node->link), 0, bucket_bounds, ibuf, &tmpibuf, ima->tpageflag & IMA_CLAMP_U, ima->tpageflag & IMA_CLAMP_V);
2741                 }
2742         }
2743         else {
2744
2745                 /* More complicated loop, switch between images */
2746                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2747                         face_index = GET_INT_FROM_POINTER(node->link);
2748
2749                         /* Image context switching */
2750                         tpage = project_paint_face_paint_image(ps, face_index);
2751                         if (tpage_last != tpage) {
2752                                 tpage_last = tpage;
2753
2754                                 for (image_index = 0; image_index < ps->image_tot; image_index++) {
2755                                         if (ps->projImages[image_index].ima == tpage_last) {
2756                                                 ibuf = ps->projImages[image_index].ibuf;
2757                                                 ima = ps->projImages[image_index].ima;
2758                                                 break;
2759                                         }
2760                                 }
2761                         }
2762                         /* context switching done */
2763
2764                         project_paint_face_init(ps, thread_index, bucket_index, face_index, image_index, bucket_bounds, ibuf, &tmpibuf, ima->tpageflag & IMA_CLAMP_U, ima->tpageflag & IMA_CLAMP_V);
2765                 }
2766         }
2767
2768         if (tmpibuf)
2769                 IMB_freeImBuf(tmpibuf);
2770
2771         ps->bucketFlags[bucket_index] |= PROJ_BUCKET_INIT;
2772 }
2773
2774
2775 /* We want to know if a bucket and a face overlap in screen-space
2776  *
2777  * Note, if this ever returns false positives its not that bad, since a face in the bounding area will have its pixels
2778  * calculated when it might not be needed later, (at the moment at least)
2779  * obviously it shouldn't have bugs though */
2780
2781 static bool project_bucket_face_isect(ProjPaintState *ps, int bucket_x, int bucket_y, const MFace *mf)
2782 {
2783         /* TODO - replace this with a tricker method that uses sideofline for all screenCoords's edges against the closest bucket corner */
2784         rctf bucket_bounds;
2785         float p1[2], p2[2], p3[2], p4[2];
2786         const float *v, *v1, *v2, *v3, *v4 = NULL;
2787         int fidx;
2788
2789         project_bucket_bounds(ps, bucket_x, bucket_y, &bucket_bounds);
2790
2791         /* Is one of the faces verts in the bucket bounds? */
2792
2793         fidx = mf->v4 ? 3 : 2;
2794         do {
2795                 v = ps->screenCoords[(*(&mf->v1 + fidx))];
2796                 if (BLI_rctf_isect_pt_v(&bucket_bounds, v)) {
2797                         return 1;
2798                 }
2799         } while (fidx--);
2800
2801         v1 = ps->screenCoords[mf->v1];
2802         v2 = ps->screenCoords[mf->v2];
2803         v3 = ps->screenCoords[mf->v3];
2804         if (mf->v4) {
2805                 v4 = ps->screenCoords[mf->v4];
2806         }
2807
2808         p1[0] = bucket_bounds.xmin; p1[1] = bucket_bounds.ymin;
2809         p2[0] = bucket_bounds.xmin; p2[1] = bucket_bounds.ymax;
2810         p3[0] = bucket_bounds.xmax; p3[1] = bucket_bounds.ymax;
2811         p4[0] = bucket_bounds.xmax; p4[1] = bucket_bounds.ymin;
2812
2813         if (mf->v4) {
2814                 if (isect_point_quad_v2(p1, v1, v2, v3, v4) ||
2815                     isect_point_quad_v2(p2, v1, v2, v3, v4) ||
2816                     isect_point_quad_v2(p3, v1, v2, v3, v4) ||
2817                     isect_point_quad_v2(p4, v1, v2, v3, v4) ||
2818
2819                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2820                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3) || isect_line_line_v2(p1, p2, v3, v4)) ||
2821                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3) || isect_line_line_v2(p2, p3, v3, v4)) ||
2822                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3) || isect_line_line_v2(p3, p4, v3, v4)) ||
2823                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3) || isect_line_line_v2(p4, p1, v3, v4)))
2824                 {
2825                         return 1;
2826                 }
2827         }
2828         else {
2829                 if (isect_point_tri_v2(p1, v1, v2, v3) ||
2830                     isect_point_tri_v2(p2, v1, v2, v3) ||
2831                     isect_point_tri_v2(p3, v1, v2, v3) ||
2832                     isect_point_tri_v2(p4, v1, v2, v3) ||
2833                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2834                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3)) ||
2835                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3)) ||
2836                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3)) ||
2837                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3)))
2838                 {
2839                         return 1;
2840                 }
2841         }
2842
2843         return 0;
2844 }
2845
2846 /* Add faces to the bucket but don't initialize its pixels
2847  * TODO - when painting occluded, sort the faces on their min-Z and only add faces that faces that are not occluded */
2848 static void project_paint_delayed_face_init(ProjPaintState *ps, const MFace *mf, const int face_index)
2849 {
2850         float min[2], max[2], *vCoSS;
2851         int bucketMin[2], bucketMax[2]; /* for  ps->bucketRect indexing */
2852         int fidx, bucket_x, bucket_y;
2853         int has_x_isect = -1, has_isect = 0; /* for early loop exit */
2854         MemArena *arena = ps->arena_mt[0]; /* just use the first thread arena since threading has not started yet */
2855
2856         INIT_MINMAX2(min, max);
2857
2858         fidx = mf->v4 ? 3 : 2;
2859         do {
2860                 vCoSS = ps->screenCoords[*(&mf->v1 + fidx)];
2861                 minmax_v2v2_v2(min, max, vCoSS);
2862         } while (fidx--);
2863
2864         project_paint_bucket_bounds(ps, min, max, bucketMin, bucketMax);
2865
2866         for (bucket_y = bucketMin[1]; bucket_y < bucketMax[1]; bucket_y++) {
2867                 has_x_isect = 0;
2868                 for (bucket_x = bucketMin[0]; bucket_x < bucketMax[0]; bucket_x++) {
2869                         if (project_bucket_face_isect(ps, bucket_x, bucket_y, mf)) {
2870                                 int bucket_index = bucket_x + (bucket_y * ps->buckets_x);
2871                                 BLI_linklist_prepend_arena(
2872                                         &ps->bucketFaces[bucket_index],
2873                                         SET_INT_IN_POINTER(face_index), /* cast to a pointer to shut up the compiler */
2874                                         arena
2875                                         );
2876
2877                                 has_x_isect = has_isect = 1;
2878                         }
2879                         else if (has_x_isect) {
2880                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */