Fix #35426, masking works wrong in projection painting. When we don't
[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 "PIL_time.h"
52
53 #include "IMB_imbuf.h"
54 #include "IMB_imbuf_types.h"
55
56 #include "DNA_brush_types.h"
57 #include "DNA_mesh_types.h"
58 #include "DNA_node_types.h"
59 #include "DNA_object_types.h"
60
61 #include "BKE_camera.h"
62 #include "BKE_context.h"
63 #include "BKE_depsgraph.h"
64 #include "BKE_DerivedMesh.h"
65 #include "BKE_idprop.h"
66 #include "BKE_brush.h"
67 #include "BKE_image.h"
68 #include "BKE_library.h"
69 #include "BKE_main.h"
70 #include "BKE_mesh.h"
71 #include "BKE_node.h"
72 #include "BKE_object.h"
73 #include "BKE_paint.h"
74 #include "BKE_report.h"
75 #include "BKE_scene.h"
76 #include "BKE_colortools.h"
77
78 #include "BKE_editmesh.h"
79
80 #include "BIF_gl.h"
81 #include "BIF_glutil.h"
82
83 #include "UI_view2d.h"
84
85 #include "ED_image.h"
86 #include "ED_screen.h"
87 #include "ED_sculpt.h"
88 #include "ED_uvedit.h"
89 #include "ED_view3d.h"
90 #include "ED_mesh.h"
91
92 #include "GPU_extensions.h"
93
94 #include "WM_api.h"
95 #include "WM_types.h"
96
97 #include "RNA_access.h"
98 #include "RNA_define.h"
99 #include "RNA_enum_types.h"
100
101 #include "GPU_draw.h"
102
103 #include "IMB_colormanagement.h"
104
105 #include "paint_intern.h"
106
107 /* Defines and Structs */
108 /* FTOCHAR as inline function */
109 BLI_INLINE unsigned char f_to_char(const float val)
110 {
111         return FTOCHAR(val);
112 }
113
114 /* ProjectionPaint defines */
115
116 /* approx the number of buckets to have under the brush,
117  * used with the brush size to set the ps->buckets_x and ps->buckets_y value.
118  *
119  * When 3 - a brush should have ~9 buckets under it at once
120  * ...this helps for threading while painting as well as
121  * avoiding initializing pixels that wont touch the brush */
122 #define PROJ_BUCKET_BRUSH_DIV 4
123
124 #define PROJ_BUCKET_RECT_MIN 4
125 #define PROJ_BUCKET_RECT_MAX 256
126
127 #define PROJ_BOUNDBOX_DIV 8
128 #define PROJ_BOUNDBOX_SQUARED  (PROJ_BOUNDBOX_DIV * PROJ_BOUNDBOX_DIV)
129
130 //#define PROJ_DEBUG_PAINT 1
131 //#define PROJ_DEBUG_NOSEAMBLEED 1
132 //#define PROJ_DEBUG_PRINT_CLIP 1
133 #define PROJ_DEBUG_WINCLIP 1
134
135 /* projectFaceSeamFlags options */
136 //#define PROJ_FACE_IGNORE      (1<<0)  /* When the face is hidden, backfacing or occluded */
137 //#define PROJ_FACE_INIT        (1<<1)  /* When we have initialized the faces data */
138 #define PROJ_FACE_SEAM1 (1 << 0)  /* If this face has a seam on any of its edges */
139 #define PROJ_FACE_SEAM2 (1 << 1)
140 #define PROJ_FACE_SEAM3 (1 << 2)
141 #define PROJ_FACE_SEAM4 (1 << 3)
142
143 #define PROJ_FACE_NOSEAM1   (1 << 4)
144 #define PROJ_FACE_NOSEAM2   (1 << 5)
145 #define PROJ_FACE_NOSEAM3   (1 << 6)
146 #define PROJ_FACE_NOSEAM4   (1 << 7)
147
148 #define PROJ_SRC_VIEW       1
149 #define PROJ_SRC_IMAGE_CAM  2
150 #define PROJ_SRC_IMAGE_VIEW 3
151
152 #define PROJ_VIEW_DATA_ID "view_data"
153 #define PROJ_VIEW_DATA_SIZE (4 * 4 + 4 * 4 + 3) /* viewmat + winmat + clipsta + clipend + is_ortho */
154
155
156 /* a slightly scaled down face is used to get fake 3D location for edge pixels in the seams
157  * as this number approaches  1.0f the likelihood increases of float precision errors where
158  * it is occluded by an adjacent face */
159 #define PROJ_FACE_SCALE_SEAM    0.99f
160
161 #define PROJ_BUCKET_NULL        0
162 #define PROJ_BUCKET_INIT        (1 << 0)
163 // #define PROJ_BUCKET_CLONE_INIT       (1<<1)
164
165 /* used for testing doubles, if a point is on a line etc */
166 #define PROJ_GEOM_TOLERANCE 0.00075f
167
168 /* vert flags */
169 #define PROJ_VERT_CULL 1
170
171 /* This is mainly a convenience struct used so we can keep an array of images we use
172  * Thir imbufs, etc, in 1 array, When using threads this array is copied for each thread
173  * because 'partRedrawRect' and 'touch' values would not be thread safe */
174 typedef struct ProjPaintImage {
175         Image *ima;
176         ImBuf *ibuf;
177         ImagePaintPartialRedraw *partRedrawRect;
178         void **undoRect; /* only used to build undo tiles after painting */
179         int touch;
180 } ProjPaintImage;
181
182 /* Main projection painting struct passed to all projection painting functions */
183 typedef struct ProjPaintState {
184         View3D *v3d;
185         RegionView3D *rv3d;
186         ARegion *ar;
187         Scene *scene;
188         int source; /* PROJ_SRC_**** */
189
190         Brush *brush;
191         short tool, blend, mode;
192         int orig_brush_size;
193         Object *ob;
194         /* end similarities with ImagePaintState */
195
196         DerivedMesh    *dm;
197         int dm_totface;
198         int dm_totvert;
199         int dm_release;
200
201         MVert          *dm_mvert;
202         MFace          *dm_mface;
203         MTFace         *dm_mtface;
204         MTFace         *dm_mtface_clone;    /* other UV map, use for cloning between layers */
205         MTFace         *dm_mtface_stencil;
206
207         /* projection painting only */
208         MemArena *arena_mt[BLENDER_MAX_THREADS]; /* for multithreading, the first item is sometimes used for non threaded cases too */
209         LinkNode **bucketRect;              /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
210         LinkNode **bucketFaces;             /* bucketRect aligned array linkList of faces overlapping each bucket */
211         unsigned char *bucketFlags;         /* store if the bucks have been initialized  */
212 #ifndef PROJ_DEBUG_NOSEAMBLEED
213         char *faceSeamFlags;                /* store info about faces, if they are initialized etc*/
214         float (*faceSeamUVs)[4][2];         /* expanded UVs for faces to use as seams */
215         LinkNode **vertFaces;               /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
216 #endif
217         char *vertFlags;                    /* store options per vert, now only store if the vert is pointing away from the view */
218         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 */
219         int buckets_y;
220
221         ProjPaintImage *projImages;
222
223         int pixel_sizeof;           /* result of project_paint_pixel_sizeof(), constant per stroke */
224
225         int image_tot;              /* size of projectImages array */
226
227         float (*screenCoords)[4];   /* verts projected into floating point screen space */
228
229         float screenMin[2];         /* 2D bounds for mesh verts on the screen's plane (screenspace) */
230         float screenMax[2];
231         float screen_width;         /* Calculated from screenMin & screenMax */
232         float screen_height;
233         int winx, winy;             /* from the carea or from the projection render */
234
235         /* options for projection painting */
236         int do_layer_clone;
237         int do_layer_stencil;
238         int do_layer_stencil_inv;
239
240         short do_occlude;               /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
241         short do_backfacecull;          /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
242         short do_mask_normal;           /* mask out pixels based on their normals */
243         short do_new_shading_nodes;     /* cache BKE_scene_use_new_shading_nodes value */
244         float normal_angle;             /* what angle to mask at*/
245         float normal_angle_inner;
246         float normal_angle_range;       /* difference between normal_angle and normal_angle_inner, for easy access */
247
248         short is_ortho;
249         bool do_masking;              /* use masking during painting. Some operations such as airbrush may disable */
250         bool is_texbrush;              /* only to avoid running  */
251         bool is_maskbrush;            /* mask brush is applied before masking */
252         bool is_maskbrush_tiled;      /* mask brush is applied after masking */
253 #ifndef PROJ_DEBUG_NOSEAMBLEED
254         float seam_bleed_px;
255 #endif
256         /* clone vars */
257         float cloneOffset[2];
258
259         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
260         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
261         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
262         float clipsta, clipend;
263
264         /* reproject vars */
265         Image *reproject_image;
266         ImBuf *reproject_ibuf;
267
268         /* threads */
269         int thread_tot;
270         int bucketMin[2];
271         int bucketMax[2];
272         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
273
274         /* redraw */
275         bool need_redraw;
276 } ProjPaintState;
277
278 typedef union pixelPointer {
279         float *f_pt;            /* float buffer */
280         unsigned int *uint_pt; /* 2 ways to access a char buffer */
281         unsigned char *ch_pt;
282 } PixelPointer;
283
284 typedef union pixelStore {
285         unsigned char ch[4];
286         unsigned int uint;
287         float f[4];
288 } PixelStore;
289
290 typedef struct ProjPixel {
291         float projCoSS[2]; /* the floating point screen projection of this pixel */
292         float worldCoSS[3];
293         /* Only used when the airbrush is disabled.
294          * Store the max mask value to avoid painting over an area with a lower opacity
295          * with an advantage that we can avoid touching the pixel at all, if the
296          * new mask value is lower then mask_accum */
297         unsigned short mask_accum;
298
299         /* for various reasons we may want to mask out painting onto this pixel */
300         unsigned short mask;
301
302         short x_px, y_px;
303
304         PixelStore origColor;
305         PixelStore newColor;
306         PixelPointer pixel;
307
308         short image_index; /* if anyone wants to paint onto more than 32768 images they can bite me */
309         unsigned char bb_cell_index;
310 } ProjPixel;
311
312 typedef struct ProjPixelClone {
313         struct ProjPixel __pp;
314         PixelStore clonepx;
315 } ProjPixelClone;
316
317 /* blur, store surrounding colors */
318 #define PROJ_PIXEL_SOFTEN_TOT 4
319 /* blur picking offset (in screenspace) */
320 #define PROJ_PIXEL_SOFTEN_OFS_PX 1.0f
321
322 static const float proj_pixel_soften_v2[PROJ_PIXEL_SOFTEN_TOT][2] = {
323         {-PROJ_PIXEL_SOFTEN_OFS_PX,                         0.0f},
324         { 0.0f,                        -PROJ_PIXEL_SOFTEN_OFS_PX},
325         { 0.0f,                         PROJ_PIXEL_SOFTEN_OFS_PX},
326         { PROJ_PIXEL_SOFTEN_OFS_PX,                         0.0f},
327 };
328
329 /* Finish projection painting structs */
330
331 static Image *project_paint_face_image(const ProjPaintState *ps, MTFace *dm_mtface, int face_index)
332 {
333         Image *ima;
334
335         if (ps->do_new_shading_nodes) { /* cached BKE_scene_use_new_shading_nodes result */
336                 MFace *mf = ps->dm_mface + face_index;
337                 ED_object_get_active_image(ps->ob, mf->mat_nr + 1, &ima, NULL, NULL);
338         }
339         else {
340                 ima = dm_mtface[face_index].tpage;
341         }
342
343         return ima;
344 }
345
346 /* fast projection bucket array lookup, use the safe version for bound checking  */
347 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
348 {
349         /* If we were not dealing with screenspace 2D coords we could simple do...
350          * ps->bucketRect[x + (y*ps->buckets_y)] */
351
352         /* please explain?
353          * projCoSS[0] - ps->screenMin[0]   : zero origin
354          * ... / ps->screen_width           : range from 0.0 to 1.0
355          * ... * ps->buckets_x              : use as a bucket index
356          *
357          * Second multiplication does similar but for vertical offset
358          */
359         return ( (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
360                (((int)(((projCoSS[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
361 }
362
363 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
364 {
365         int bucket_index = project_bucket_offset(ps, projCoSS);
366
367         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
368                 return -1;
369         }
370         else {
371                 return bucket_index;
372         }
373 }
374
375 /* still use 2D X,Y space but this works for verts transformed by a perspective matrix, using their 4th component as a weight */
376 static void barycentric_weights_v2_persp(const float v1[4], const float v2[4], const float v3[4], const float co[2], float w[3])
377 {
378         float wtot_inv, wtot;
379
380         w[0] = area_tri_signed_v2(v2, v3, co) / v1[3];
381         w[1] = area_tri_signed_v2(v3, v1, co) / v2[3];
382         w[2] = area_tri_signed_v2(v1, v2, co) / v3[3];
383         wtot = w[0] + w[1] + w[2];
384
385         if (wtot != 0.0f) {
386                 wtot_inv = 1.0f / wtot;
387
388                 w[0] = w[0] * wtot_inv;
389                 w[1] = w[1] * wtot_inv;
390                 w[2] = w[2] * wtot_inv;
391         }
392         else /* dummy values for zero area face */
393                 w[0] = w[1] = w[2] = 1.0f / 3.0f;
394 }
395
396 static float VecZDepthOrtho(const float pt[2],
397                             const float v1[3], const float v2[3], const float v3[3],
398                             float w[3])
399 {
400         barycentric_weights_v2(v1, v2, v3, pt, w);
401         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
402 }
403
404 static float VecZDepthPersp(const float pt[2],
405                             const float v1[4], const float v2[4], const float v3[4],
406                             float w[3])
407 {
408         float wtot_inv, wtot;
409         float w_tmp[3];
410
411         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
412         /* for the depth we need the weights to match what
413          * barycentric_weights_v2 would return, in this case its easiest just to
414          * undo the 4th axis division and make it unit-sum
415          *
416          * don't call barycentric_weights_v2() because our callers expect 'w'
417          * to be weighted from the perspective */
418         w_tmp[0] = w[0] * v1[3];
419         w_tmp[1] = w[1] * v2[3];
420         w_tmp[2] = w[2] * v3[3];
421
422         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
423
424         if (wtot != 0.0f) {
425                 wtot_inv = 1.0f / wtot;
426
427                 w_tmp[0] = w_tmp[0] * wtot_inv;
428                 w_tmp[1] = w_tmp[1] * wtot_inv;
429                 w_tmp[2] = w_tmp[2] * wtot_inv;
430         }
431         else /* dummy values for zero area face */
432                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
433         /* done mimicing barycentric_weights_v2() */
434
435         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
436 }
437
438
439 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
440 static int project_paint_PickFace(const ProjPaintState *ps, const float pt[2], float w[3], int *side)
441 {
442         LinkNode *node;
443         float w_tmp[3];
444         float *v1, *v2, *v3, *v4;
445         int bucket_index;
446         int face_index;
447         int best_side = -1;
448         int best_face_index = -1;
449         float z_depth_best = FLT_MAX, z_depth;
450         MFace *mf;
451
452         bucket_index = project_bucket_offset_safe(ps, pt);
453         if (bucket_index == -1)
454                 return -1;
455
456
457
458         /* we could return 0 for 1 face buckets, as long as this function assumes
459          * that the point its testing is only every originated from an existing face */
460
461         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
462                 face_index = GET_INT_FROM_POINTER(node->link);
463                 mf = ps->dm_mface + face_index;
464
465                 v1 = ps->screenCoords[mf->v1];
466                 v2 = ps->screenCoords[mf->v2];
467                 v3 = ps->screenCoords[mf->v3];
468
469                 if (isect_point_tri_v2(pt, v1, v2, v3)) {
470                         if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v2, v3, w_tmp);
471                         else z_depth = VecZDepthPersp(pt, v1, v2, v3, w_tmp);
472
473                         if (z_depth < z_depth_best) {
474                                 best_face_index = face_index;
475                                 best_side = 0;
476                                 z_depth_best = z_depth;
477                                 copy_v3_v3(w, w_tmp);
478                         }
479                 }
480                 else if (mf->v4) {
481                         v4 = ps->screenCoords[mf->v4];
482
483                         if (isect_point_tri_v2(pt, v1, v3, v4)) {
484                                 if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v3, v4, w_tmp);
485                                 else z_depth = VecZDepthPersp(pt, v1, v3, v4, w_tmp);
486
487                                 if (z_depth < z_depth_best) {
488                                         best_face_index = face_index;
489                                         best_side = 1;
490                                         z_depth_best = z_depth;
491                                         copy_v3_v3(w, w_tmp);
492                                 }
493                         }
494                 }
495         }
496
497         *side = best_side;
498         return best_face_index; /* will be -1 or a valid face */
499 }
500
501 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
502 static void uvco_to_wrapped_pxco(const float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
503 {
504         /* use */
505         *x = (float)fmodf(uv[0], 1.0f);
506         *y = (float)fmodf(uv[1], 1.0f);
507
508         if (*x < 0.0f) *x += 1.0f;
509         if (*y < 0.0f) *y += 1.0f;
510
511         *x = *x * ibuf_x - 0.5f;
512         *y = *y * ibuf_y - 0.5f;
513 }
514
515 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
516 static int project_paint_PickColor(const ProjPaintState *ps, const float pt[2],
517                                    float *rgba_fp, unsigned char *rgba, const int interp)
518 {
519         float w[3], uv[2];
520         int side;
521         int face_index;
522         MTFace *tf;
523         Image *ima;
524         ImBuf *ibuf;
525         int xi, yi;
526
527
528         face_index = project_paint_PickFace(ps, pt, w, &side);
529
530         if (face_index == -1)
531                 return 0;
532
533         tf = ps->dm_mtface + face_index;
534
535         if (side == 0) {
536                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[1], tf->uv[2], w);
537         }
538         else { /* QUAD */
539                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[2], tf->uv[3], w);
540         }
541
542         ima = project_paint_face_image(ps, ps->dm_mtface, face_index);
543         ibuf = ima->ibufs.first; /* we must have got the imbuf before getting here */
544         if (!ibuf) return 0;
545
546         if (interp) {
547                 float x, y;
548                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
549
550                 if (ibuf->rect_float) {
551                         if (rgba_fp) {
552                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
553                         }
554                         else {
555                                 float rgba_tmp_f[4];
556                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
557                                 premul_float_to_straight_uchar(rgba, rgba_tmp_f);
558                         }
559                 }
560                 else {
561                         if (rgba) {
562                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
563                         }
564                         else {
565                                 unsigned char rgba_tmp[4];
566                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
567                                 straight_uchar_to_premul_float(rgba_fp, rgba_tmp);
568                         }
569                 }
570         }
571         else {
572                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
573                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
574                 //if (xi < 0 || xi >= ibuf->x  ||  yi < 0 || yi >= ibuf->y) return 0;
575
576                 /* wrap */
577                 xi = ((int)(uv[0] * ibuf->x)) % ibuf->x;
578                 if (xi < 0) xi += ibuf->x;
579                 yi = ((int)(uv[1] * ibuf->y)) % ibuf->y;
580                 if (yi < 0) yi += ibuf->y;
581
582
583                 if (rgba) {
584                         if (ibuf->rect_float) {
585                                 float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
586                                 premul_float_to_straight_uchar(rgba, rgba_tmp_fp);
587                         }
588                         else {
589                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
590                         }
591                 }
592
593                 if (rgba_fp) {
594                         if (ibuf->rect_float) {
595                                 copy_v4_v4(rgba_fp, (ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
596                         }
597                         else {
598                                 unsigned char *tmp_ch = ((unsigned char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
599                                 straight_uchar_to_premul_float(rgba_fp, tmp_ch);
600                         }
601                 }
602         }
603         return 1;
604 }
605
606 /* Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusuion test)
607  * return...
608  *  0   : no occlusion
609  * -1   : no occlusion but 2D intersection is true (avoid testing the other half of a quad)
610  *  1   : occluded
611  *  2   : occluded with w[3] weights set (need to know in some cases) */
612
613 static int project_paint_occlude_ptv(float pt[3], float v1[4], float v2[4], float v3[4], float w[3], int is_ortho)
614 {
615         /* if all are behind us, return false */
616         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
617                 return 0;
618
619         /* do a 2D point in try intersection */
620         if (!isect_point_tri_v2(pt, v1, v2, v3))
621                 return 0;  /* we know there is  */
622
623
624         /* From here on we know there IS an intersection */
625         /* if ALL of the verts are infront of us then we know it intersects ? */
626         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
627                 return 1;
628         }
629         else {
630                 /* we intersect? - find the exact depth at the point of intersection */
631                 /* Is this point is occluded by another face? */
632                 if (is_ortho) {
633                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
634                 }
635                 else {
636                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
637                 }
638         }
639         return -1;
640 }
641
642
643 static int project_paint_occlude_ptv_clip(const ProjPaintState *ps, const MFace *mf,
644                                           float pt[3], float v1[4], float v2[4], float v3[4],
645                                           const int side)
646 {
647         float w[3], wco[3];
648         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, ps->is_ortho);
649
650         if (ret <= 0)
651                 return ret;
652
653         if (ret == 1) { /* weights not calculated */
654                 if (ps->is_ortho) barycentric_weights_v2(v1, v2, v3, pt, w);
655                 else barycentric_weights_v2_persp(v1, v2, v3, pt, w);
656         }
657
658         /* Test if we're in the clipped area, */
659         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);
660         else interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
661
662         if (!ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
663                 return 1;
664         }
665
666         return -1;
667 }
668
669
670 /* Check if a screenspace location is occluded by any other faces
671  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
672  * and doesn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
673 static int project_bucket_point_occluded(const ProjPaintState *ps, LinkNode *bucketFace, const int orig_face, float pixelScreenCo[4])
674 {
675         MFace *mf;
676         int face_index;
677         int isect_ret;
678         float w[3]; /* not needed when clipping */
679         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
680
681         /* we could return 0 for 1 face buckets, as long as this function assumes
682          * that the point its testing is only every originated from an existing face */
683
684         for (; bucketFace; bucketFace = bucketFace->next) {
685                 face_index = GET_INT_FROM_POINTER(bucketFace->link);
686
687                 if (orig_face != face_index) {
688                         mf = ps->dm_mface + face_index;
689                         if (do_clip)
690                                 isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], 0);
691                         else
692                                 isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], w, ps->is_ortho);
693
694                         /* Note, if (isect_ret == -1) then we don't want to test the other side of the quad */
695                         if (isect_ret == 0 && mf->v4) {
696                                 if (do_clip)
697                                         isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], 1);
698                                 else
699                                         isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], w, ps->is_ortho);
700                         }
701                         if (isect_ret >= 1) {
702                                 /* TODO - we may want to cache the first hit,
703                                  * it is not possible to swap the face order in the list anymore */
704                                 return 1;
705                         }
706                 }
707         }
708         return 0;
709 }
710
711 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
712  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
713 #define ISECT_TRUE 1
714 #define ISECT_TRUE_P1 2
715 #define ISECT_TRUE_P2 3
716 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
717 {
718         float y_diff;
719
720         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
721                 *x_isect = p1[0];
722                 return ISECT_TRUE_P1;
723         }
724         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
725                 *x_isect = p2[0];
726                 return ISECT_TRUE_P2;
727         }
728
729         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
730
731         if (y_diff < 0.000001f) {
732                 *x_isect = (p1[0] + p2[0]) * 0.5f;
733                 return ISECT_TRUE;
734         }
735
736         if (p1[1] > y_level && p2[1] < y_level) {
737                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /*(p1[1]-p2[1]);*/
738                 return ISECT_TRUE;
739         }
740         else if (p1[1] < y_level && p2[1] > y_level) {
741                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /*(p2[1]-p1[1]);*/
742                 return ISECT_TRUE;
743         }
744         else {
745                 return 0;
746         }
747 }
748
749 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
750 {
751         float x_diff;
752
753         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
754                 *y_isect = p1[1];
755                 return ISECT_TRUE_P1;
756         }
757         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
758                 *y_isect = p2[1];
759                 return ISECT_TRUE_P2;
760         }
761
762         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
763
764         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
765                 *y_isect = (p1[0] + p2[0]) * 0.5f;
766                 return ISECT_TRUE;
767         }
768
769         if (p1[0] > x_level && p2[0] < x_level) {
770                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff; /*(p1[0]-p2[0]);*/
771                 return ISECT_TRUE;
772         }
773         else if (p1[0] < x_level && p2[0] > x_level) {
774                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff; /*(p2[0]-p1[0]);*/
775                 return ISECT_TRUE;
776         }
777         else {
778                 return 0;
779         }
780 }
781
782 /* simple func use for comparing UV locations to check if there are seams.
783  * Its possible this gives incorrect results, when the UVs for 1 face go into the next
784  * tile, but do not do this for the adjacent face, it could return a false positive.
785  * This is so unlikely that Id not worry about it. */
786 #ifndef PROJ_DEBUG_NOSEAMBLEED
787 static int cmp_uv(const float vec2a[2], const float vec2b[2])
788 {
789         /* if the UV's are not between 0.0 and 1.0 */
790         float xa = (float)fmodf(vec2a[0], 1.0f);
791         float ya = (float)fmodf(vec2a[1], 1.0f);
792
793         float xb = (float)fmodf(vec2b[0], 1.0f);
794         float yb = (float)fmodf(vec2b[1], 1.0f);
795
796         if (xa < 0.0f) xa += 1.0f;
797         if (ya < 0.0f) ya += 1.0f;
798
799         if (xb < 0.0f) xb += 1.0f;
800         if (yb < 0.0f) yb += 1.0f;
801
802         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
803 }
804 #endif
805
806 /* set min_px and max_px to the image space bounds of the UV coords
807  * return zero if there is no area in the returned rectangle */
808 #ifndef PROJ_DEBUG_NOSEAMBLEED
809 static int pixel_bounds_uv(
810         const float uv1[2], const float uv2[2], const float uv3[2], const float uv4[2],
811         rcti *bounds_px,
812         const int ibuf_x, const int ibuf_y,
813         int is_quad
814         )
815 {
816         float min_uv[2], max_uv[2]; /* UV bounds */
817
818         INIT_MINMAX2(min_uv, max_uv);
819
820         minmax_v2v2_v2(min_uv, max_uv, uv1);
821         minmax_v2v2_v2(min_uv, max_uv, uv2);
822         minmax_v2v2_v2(min_uv, max_uv, uv3);
823         if (is_quad)
824                 minmax_v2v2_v2(min_uv, max_uv, uv4);
825
826         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
827         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
828
829         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
830         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
831
832         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
833
834         /* face uses no UV area when quantized to pixels? */
835         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
836 }
837 #endif
838
839 static int pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
840 {
841         float min_uv[2], max_uv[2]; /* UV bounds */
842
843         if (tot == 0) {
844                 return 0;
845         }
846
847         INIT_MINMAX2(min_uv, max_uv);
848
849         while (tot--) {
850                 minmax_v2v2_v2(min_uv, max_uv, (*uv));
851                 uv++;
852         }
853
854         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
855         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
856
857         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
858         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
859
860         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
861
862         /* face uses no UV area when quantized to pixels? */
863         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
864 }
865
866 #ifndef PROJ_DEBUG_NOSEAMBLEED
867
868 /* This function returns 1 if this face has a seam along the 2 face-vert indices
869  * 'orig_i1_fidx' and 'orig_i2_fidx' */
870 static int check_seam(const ProjPaintState *ps, const int orig_face, const int orig_i1_fidx, const int orig_i2_fidx, int *other_face, int *orig_fidx)
871 {
872         LinkNode *node;
873         int face_index;
874         unsigned int i1, i2;
875         int i1_fidx = -1, i2_fidx = -1; /* index in face */
876         MFace *mf;
877         MTFace *tf;
878         const MFace *orig_mf = ps->dm_mface + orig_face;
879         const MTFace *orig_tf = ps->dm_mtface + orig_face;
880
881         /* vert indices from face vert order indices */
882         i1 = (*(&orig_mf->v1 + orig_i1_fidx));
883         i2 = (*(&orig_mf->v1 + orig_i2_fidx));
884
885         for (node = ps->vertFaces[i1]; node; node = node->next) {
886                 face_index = GET_INT_FROM_POINTER(node->link);
887
888                 if (face_index != orig_face) {
889                         mf = ps->dm_mface + face_index;
890                         /* could check if the 2 faces images match here,
891                          * but then there wouldn't be a way to return the opposite face's info */
892
893
894                         /* We need to know the order of the verts in the adjacent face
895                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
896                         if      (mf->v1 == i1) i1_fidx = 0;
897                         else if (mf->v2 == i1) i1_fidx = 1;
898                         else if (mf->v3 == i1) i1_fidx = 2;
899                         else if (mf->v4 && mf->v4 == i1) i1_fidx = 3;
900
901                         if      (mf->v1 == i2) i2_fidx = 0;
902                         else if (mf->v2 == i2) i2_fidx = 1;
903                         else if (mf->v3 == i2) i2_fidx = 2;
904                         else if (mf->v4 && mf->v4 == i2) i2_fidx = 3;
905
906                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
907                         if (i2_fidx != -1) {
908                                 Image *tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
909                                 Image *orig_tpage = project_paint_face_image(ps, ps->dm_mtface, orig_face);
910
911                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
912                                 tf = ps->dm_mtface + face_index;
913
914                                 /* set up the other face */
915                                 *other_face = face_index;
916                                 *orig_fidx = (i1_fidx < i2_fidx) ? i1_fidx : i2_fidx;
917
918                                 /* first test if they have the same image */
919                                 if ((orig_tpage == tpage) &&
920                                     cmp_uv(orig_tf->uv[orig_i1_fidx], tf->uv[i1_fidx]) &&
921                                     cmp_uv(orig_tf->uv[orig_i2_fidx], tf->uv[i2_fidx]) )
922                                 {
923                                         // printf("SEAM (NONE)\n");
924                                         return 0;
925
926                                 }
927                                 else {
928                                         // printf("SEAM (UV GAP)\n");
929                                         return 1;
930                                 }
931                         }
932                 }
933         }
934         // printf("SEAM (NO FACE)\n");
935         *other_face = -1;
936         return 1;
937 }
938
939 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
940  * since the outset coords are a margin that keep an even distance from the original UV's,
941  * note that the image aspect is taken into account */
942 static void uv_image_outset(float (*orig_uv)[2], float (*outset_uv)[2], const float scaler,
943                             const int ibuf_x, const int ibuf_y, const int is_quad)
944 {
945         float a1, a2, a3, a4 = 0.0f;
946         float puv[4][2]; /* pixelspace uv's */
947         float no1[2], no2[2], no3[2], no4[2]; /* normals */
948         float dir1[2], dir2[2], dir3[2], dir4[2];
949         float ibuf_inv[2];
950
951         ibuf_inv[0] = 1.0f / (float)ibuf_x;
952         ibuf_inv[1] = 1.0f / (float)ibuf_y;
953
954         /* make UV's in pixel space so we can */
955         puv[0][0] = orig_uv[0][0] * ibuf_x;
956         puv[0][1] = orig_uv[0][1] * ibuf_y;
957
958         puv[1][0] = orig_uv[1][0] * ibuf_x;
959         puv[1][1] = orig_uv[1][1] * ibuf_y;
960
961         puv[2][0] = orig_uv[2][0] * ibuf_x;
962         puv[2][1] = orig_uv[2][1] * ibuf_y;
963
964         if (is_quad) {
965                 puv[3][0] = orig_uv[3][0] * ibuf_x;
966                 puv[3][1] = orig_uv[3][1] * ibuf_y;
967         }
968
969         /* face edge directions */
970         sub_v2_v2v2(dir1, puv[1], puv[0]);
971         sub_v2_v2v2(dir2, puv[2], puv[1]);
972         normalize_v2(dir1);
973         normalize_v2(dir2);
974
975         if (is_quad) {
976                 sub_v2_v2v2(dir3, puv[3], puv[2]);
977                 sub_v2_v2v2(dir4, puv[0], puv[3]);
978                 normalize_v2(dir3);
979                 normalize_v2(dir4);
980         }
981         else {
982                 sub_v2_v2v2(dir3, puv[0], puv[2]);
983                 normalize_v2(dir3);
984         }
985
986         /* TODO - angle_normalized_v2v2(...) * (M_PI/180.0f)
987          * This is incorrect. Its already given radians but without it wont work.
988          * need to look into a fix - campbell */
989         if (is_quad) {
990                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir4, dir1) * ((float)M_PI / 180.0f));
991                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI / 180.0f));
992                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI / 180.0f));
993                 a4 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir4) * ((float)M_PI / 180.0f));
994         }
995         else {
996                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir1) * ((float)M_PI / 180.0f));
997                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI / 180.0f));
998                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI / 180.0f));
999         }
1000
1001         if (is_quad) {
1002                 sub_v2_v2v2(no1, dir4, dir1);
1003                 sub_v2_v2v2(no2, dir1, dir2);
1004                 sub_v2_v2v2(no3, dir2, dir3);
1005                 sub_v2_v2v2(no4, dir3, dir4);
1006                 normalize_v2(no1);
1007                 normalize_v2(no2);
1008                 normalize_v2(no3);
1009                 normalize_v2(no4);
1010                 mul_v2_fl(no1, a1 * scaler);
1011                 mul_v2_fl(no2, a2 * scaler);
1012                 mul_v2_fl(no3, a3 * scaler);
1013                 mul_v2_fl(no4, a4 * scaler);
1014                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1015                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1016                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1017                 add_v2_v2v2(outset_uv[3], puv[3], no4);
1018                 mul_v2_v2(outset_uv[0], ibuf_inv);
1019                 mul_v2_v2(outset_uv[1], ibuf_inv);
1020                 mul_v2_v2(outset_uv[2], ibuf_inv);
1021                 mul_v2_v2(outset_uv[3], ibuf_inv);
1022         }
1023         else {
1024                 sub_v2_v2v2(no1, dir3, dir1);
1025                 sub_v2_v2v2(no2, dir1, dir2);
1026                 sub_v2_v2v2(no3, dir2, dir3);
1027                 normalize_v2(no1);
1028                 normalize_v2(no2);
1029                 normalize_v2(no3);
1030                 mul_v2_fl(no1, a1 * scaler);
1031                 mul_v2_fl(no2, a2 * scaler);
1032                 mul_v2_fl(no3, a3 * scaler);
1033                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1034                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1035                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1036
1037                 mul_v2_v2(outset_uv[0], ibuf_inv);
1038                 mul_v2_v2(outset_uv[1], ibuf_inv);
1039                 mul_v2_v2(outset_uv[2], ibuf_inv);
1040         }
1041 }
1042
1043 /*
1044  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1045  * 1<<i - where i is (0-3)
1046  *
1047  * If we're multithreadng, make sure threads are locked when this is called
1048  */
1049 static void project_face_seams_init(const ProjPaintState *ps, const int face_index, const int is_quad)
1050 {
1051         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1052         int fidx1 = is_quad ? 3 : 2;
1053         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 */
1054
1055         do {
1056                 if ((ps->faceSeamFlags[face_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1057                         if (check_seam(ps, face_index, fidx1, fidx2, &other_face, &other_fidx)) {
1058                                 ps->faceSeamFlags[face_index] |= 1 << fidx1;
1059                                 if (other_face != -1)
1060                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1061                         }
1062                         else {
1063                                 ps->faceSeamFlags[face_index] |= 16 << fidx1;
1064                                 if (other_face != -1)
1065                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1066                         }
1067                 }
1068
1069                 fidx2 = fidx1;
1070         } while (fidx1--);
1071 }
1072 #endif // PROJ_DEBUG_NOSEAMBLEED
1073
1074
1075 /* Converts a UV location to a 3D screenspace location
1076  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1077  *
1078  * This is used for finding a pixels location in screenspace for painting */
1079 static void screen_px_from_ortho(
1080         float uv[2],
1081         float v1co[3], float v2co[3], float v3co[3],  /* Screenspace coords */
1082         float uv1co[2], float uv2co[2], float uv3co[2],
1083         float pixelScreenCo[4],
1084         float w[3])
1085 {
1086         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1087         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1088 }
1089
1090 /* same as screen_px_from_ortho except we need to take into account
1091  * the perspective W coord for each vert */
1092 static void screen_px_from_persp(
1093         float uv[2],
1094         float v1co[4], float v2co[4], float v3co[4],  /* screenspace coords */
1095         float uv1co[2], float uv2co[2], float uv3co[2],
1096         float pixelScreenCo[4],
1097         float w[3])
1098 {
1099
1100         float wtot_inv, wtot;
1101         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1102
1103         /* re-weight from the 4th coord of each screen vert */
1104         w[0] *= v1co[3];
1105         w[1] *= v2co[3];
1106         w[2] *= v3co[3];
1107
1108         wtot = w[0] + w[1] + w[2];
1109
1110         if (wtot > 0.0f) {
1111                 wtot_inv = 1.0f / wtot;
1112                 w[0] *= wtot_inv;
1113                 w[1] *= wtot_inv;
1114                 w[2] *= wtot_inv;
1115         }
1116         else {
1117                 w[0] = w[1] = w[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1118         }
1119         /* done re-weighting */
1120
1121         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1122 }
1123
1124 static void project_face_pixel(const MTFace *tf_other, ImBuf *ibuf_other, const float w[3],
1125                                int side, unsigned char rgba_ub[4], float rgba_f[4])
1126 {
1127         float *uvCo1, *uvCo2, *uvCo3;
1128         float uv_other[2], x, y;
1129
1130         uvCo1 =  (float *)tf_other->uv[0];
1131         if (side == 1) {
1132                 uvCo2 =  (float *)tf_other->uv[2];
1133                 uvCo3 =  (float *)tf_other->uv[3];
1134         }
1135         else {
1136                 uvCo2 =  (float *)tf_other->uv[1];
1137                 uvCo3 =  (float *)tf_other->uv[2];
1138         }
1139
1140         interp_v2_v2v2v2(uv_other, uvCo1, uvCo2, uvCo3, (float *)w);
1141
1142         /* use */
1143         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1144
1145
1146         if (ibuf_other->rect_float) { /* from float to float */
1147                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1148         }
1149         else { /* from char to float */
1150                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1151         }
1152
1153 }
1154
1155 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1156 static float project_paint_uvpixel_mask(
1157         const ProjPaintState *ps,
1158         const int face_index,
1159         const int side,
1160         const float w[3])
1161 {
1162         float mask;
1163
1164         /* Image Mask */
1165         if (ps->do_layer_stencil) {
1166                 /* another UV maps image is masking this one's */
1167                 ImBuf *ibuf_other;
1168                 Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_stencil, face_index);
1169                 const MTFace *tf_other = ps->dm_mtface_stencil + face_index;
1170
1171                 if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1172                         /* BKE_image_acquire_ibuf - TODO - this may be slow */
1173                         unsigned char rgba_ub[4];
1174                         float rgba_f[4];
1175
1176                         project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, rgba_f);
1177
1178                         if (ibuf_other->rect_float) { /* from float to float */
1179                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) * (1.0f / 3.0f)) * rgba_f[3];
1180                         }
1181                         else { /* from char to float */
1182                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) * (1.0f / (255.0f * 3.0f))) * (rgba_ub[3] * (1.0f / 255.0f));
1183                         }
1184
1185                         BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1186
1187                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1188                                 mask = (1.0f - mask);
1189
1190                         if (mask == 0.0f) {
1191                                 return 0.0f;
1192                         }
1193                 }
1194                 else {
1195                         return 0.0f;
1196                 }
1197         }
1198         else {
1199                 mask = 1.0f;
1200         }
1201
1202         /* calculate mask */
1203         if (ps->do_mask_normal) {
1204                 MFace *mf = &ps->dm_mface[face_index];
1205                 float no[3], angle;
1206                 if (mf->flag & ME_SMOOTH) {
1207                         short *no1, *no2, *no3;
1208                         no1 = ps->dm_mvert[mf->v1].no;
1209                         if (side == 1) {
1210                                 no2 = ps->dm_mvert[mf->v3].no;
1211                                 no3 = ps->dm_mvert[mf->v4].no;
1212                         }
1213                         else {
1214                                 no2 = ps->dm_mvert[mf->v2].no;
1215                                 no3 = ps->dm_mvert[mf->v3].no;
1216                         }
1217
1218                         no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1219                         no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1220                         no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1221                         normalize_v3(no);
1222                 }
1223                 else {
1224                         /* incase the */
1225 #if 1
1226                         /* normalizing per pixel isn't optimal, we could cache or check ps->*/
1227                         if (mf->v4)
1228                                 normal_quad_v3(no,
1229                                                ps->dm_mvert[mf->v1].co,
1230                                                ps->dm_mvert[mf->v2].co,
1231                                                ps->dm_mvert[mf->v3].co,
1232                                                ps->dm_mvert[mf->v4].co);
1233                         else
1234                                 normal_tri_v3(no,
1235                                               ps->dm_mvert[mf->v1].co,
1236                                               ps->dm_mvert[mf->v2].co,
1237                                               ps->dm_mvert[mf->v3].co);
1238 #else
1239                         /* don't use because some modifiers dont have normal data (subsurf for eg) */
1240                         copy_v3_v3(no, (float *)ps->dm->getTessFaceData(ps->dm, face_index, CD_NORMAL));
1241 #endif
1242                 }
1243
1244                 /* now we can use the normal as a mask */
1245                 if (ps->is_ortho) {
1246                         angle = angle_normalized_v3v3((float *)ps->viewDir, no);
1247                 }
1248                 else {
1249                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1250                         float viewDirPersp[3];
1251                         float *co1, *co2, *co3;
1252                         co1 = ps->dm_mvert[mf->v1].co;
1253                         if (side == 1) {
1254                                 co2 = ps->dm_mvert[mf->v3].co;
1255                                 co3 = ps->dm_mvert[mf->v4].co;
1256                         }
1257                         else {
1258                                 co2 = ps->dm_mvert[mf->v2].co;
1259                                 co3 = ps->dm_mvert[mf->v3].co;
1260                         }
1261
1262                         /* Get the direction from the viewPoint to the pixel and normalize */
1263                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1264                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1265                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1266                         normalize_v3(viewDirPersp);
1267
1268                         angle = angle_normalized_v3v3(viewDirPersp, no);
1269                 }
1270
1271                 if (angle >= ps->normal_angle) {
1272                         return 0.0f; /* outsize the normal limit*/
1273                 }
1274                 else if (angle > ps->normal_angle_inner) {
1275                         mask *= (ps->normal_angle - angle) / ps->normal_angle_range;
1276                 } /* otherwise no mask normal is needed, were within the limit */
1277         }
1278
1279         /* This only works when the opacity dosnt change while painting, stylus pressure messes with this
1280          * so don't use it. */
1281         // if (ps->is_airbrush == 0) mask *= BKE_brush_alpha_get(ps->brush);
1282
1283         return mask;
1284 }
1285
1286 static int project_paint_pixel_sizeof(const short tool)
1287 {
1288         if ((tool == PAINT_TOOL_CLONE) || (tool == PAINT_TOOL_SMEAR)) {
1289                 return sizeof(ProjPixelClone);
1290         }
1291         else {
1292                 return sizeof(ProjPixel);
1293         }
1294 }
1295
1296
1297 /* run this function when we know a bucket's, face's pixel can be initialized,
1298  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1299 static ProjPixel *project_paint_uvpixel_init(
1300         const ProjPaintState *ps,
1301         MemArena *arena,
1302         const ImBuf *ibuf,
1303         short x_px, short y_px,
1304         const float mask,
1305         const int face_index,
1306         const int image_index,
1307         const float pixelScreenCo[4],
1308         const float world_spaceCo[3],
1309         const int side,
1310         const float w[3])
1311 {
1312         ProjPixel *projPixel;
1313
1314         /* wrap pixel location */
1315         x_px = x_px % ibuf->x;
1316         if (x_px < 0) x_px += ibuf->x;
1317         y_px = y_px % ibuf->y;
1318         if (y_px < 0) y_px += ibuf->y;
1319
1320         BLI_assert(ps->pixel_sizeof == project_paint_pixel_sizeof(ps->tool));
1321         projPixel = (ProjPixel *)BLI_memarena_alloc(arena, ps->pixel_sizeof);
1322         //memset(projPixel, 0, size);
1323
1324         if (ibuf->rect_float) {
1325                 projPixel->pixel.f_pt = ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1326                 projPixel->origColor.f[0] = projPixel->pixel.f_pt[0];
1327                 projPixel->origColor.f[1] = projPixel->pixel.f_pt[1];
1328                 projPixel->origColor.f[2] = projPixel->pixel.f_pt[2];
1329                 projPixel->origColor.f[3] = projPixel->pixel.f_pt[3];
1330                 zero_v4(projPixel->newColor.f);
1331         }
1332         else {
1333                 projPixel->pixel.ch_pt = ((unsigned char *)ibuf->rect + ((x_px + y_px * ibuf->x) * 4));
1334                 projPixel->origColor.uint = *projPixel->pixel.uint_pt;
1335                 projPixel->newColor.uint = 0;
1336         }
1337
1338         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1339         if (ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D) {
1340                 copy_v3_v3(projPixel->worldCoSS, world_spaceCo);
1341         }
1342
1343         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1344
1345         projPixel->x_px = x_px;
1346         projPixel->y_px = y_px;
1347
1348         projPixel->mask = (unsigned short)(mask * 65535);
1349         projPixel->mask_accum = 0;
1350
1351         /* which bounding box cell are we in?, needed for undo */
1352         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1353                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1354
1355         /* done with view3d_project_float inline */
1356         if (ps->tool == PAINT_TOOL_CLONE) {
1357                 if (ps->dm_mtface_clone) {
1358                         ImBuf *ibuf_other;
1359                         Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_clone, face_index);
1360                         const MTFace *tf_other = ps->dm_mtface_clone + face_index;
1361
1362                         if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1363                                 /* BKE_image_acquire_ibuf - TODO - this may be slow */
1364
1365                                 if (ibuf->rect_float) {
1366                                         if (ibuf_other->rect_float) { /* from float to float */
1367                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1368                                         }
1369                                         else { /* from char to float */
1370                                                 unsigned char rgba_ub[4];
1371                                                 float rgba[4];
1372                                                 project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, NULL);
1373                                                 srgb_to_linearrgb_uchar4(rgba, rgba_ub);
1374                                                 straight_to_premul_v4_v4(((ProjPixelClone *)projPixel)->clonepx.f, rgba);
1375                                         }
1376                                 }
1377                                 else {
1378                                         if (ibuf_other->rect_float) { /* float to char */
1379                                                 float rgba[4];
1380                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, rgba);
1381                                                 premul_to_straight_v4(rgba);
1382                                                 linearrgb_to_srgb_uchar3(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1383                                         }
1384                                         else { /* char to char */
1385                                                 project_face_pixel(tf_other, ibuf_other, w, side, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1386                                         }
1387                                 }
1388
1389                                 BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1390                         }
1391                         else {
1392                                 if (ibuf->rect_float) {
1393                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1394                                 }
1395                                 else {
1396                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1397                                 }
1398                         }
1399
1400                 }
1401                 else {
1402                         float co[2];
1403                         sub_v2_v2v2(co, projPixel->projCoSS, (float *)ps->cloneOffset);
1404
1405                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1406                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1407                         if (ibuf->rect_float) {
1408                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1409                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1410                                 }
1411                         }
1412                         else {
1413                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1414                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1415                                 }
1416                         }
1417                 }
1418         }
1419
1420 #ifdef PROJ_DEBUG_PAINT
1421         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1422         else                  projPixel->pixel.ch_pt[0] = 0;
1423 #endif
1424         projPixel->image_index = image_index;
1425
1426         return projPixel;
1427 }
1428
1429 static int line_clip_rect2f(
1430         rctf *rect,
1431         const float l1[2], const float l2[2],
1432         float l1_clip[2], float l2_clip[2])
1433 {
1434         /* first account for horizontal, then vertical lines */
1435         /* horiz */
1436         if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) {
1437                 /* is the line out of range on its Y axis? */
1438                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1439                         return 0;
1440                 }
1441                 /* line is out of range on its X axis */
1442                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1443                         return 0;
1444                 }
1445
1446
1447                 if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1448                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1449                                 copy_v2_v2(l1_clip, l1);
1450                                 copy_v2_v2(l2_clip, l2);
1451                                 return 1;
1452                         }
1453                         else {
1454                                 return 0;
1455                         }
1456                 }
1457
1458                 copy_v2_v2(l1_clip, l1);
1459                 copy_v2_v2(l2_clip, l2);
1460                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1461                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1462                 return 1;
1463         }
1464         else if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) {
1465                 /* is the line out of range on its X axis? */
1466                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1467                         return 0;
1468                 }
1469
1470                 /* line is out of range on its Y axis */
1471                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1472                         return 0;
1473                 }
1474
1475                 if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1476                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1477                                 copy_v2_v2(l1_clip, l1);
1478                                 copy_v2_v2(l2_clip, l2);
1479                                 return 1;
1480                         }
1481                         else {
1482                                 return 0;
1483                         }
1484                 }
1485
1486                 copy_v2_v2(l1_clip, l1);
1487                 copy_v2_v2(l2_clip, l2);
1488                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1489                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1490                 return 1;
1491         }
1492         else {
1493                 float isect;
1494                 short ok1 = 0;
1495                 short ok2 = 0;
1496
1497                 /* Done with vertical lines */
1498
1499                 /* are either of the points inside the rectangle ? */
1500                 if (BLI_rctf_isect_pt_v(rect, l1)) {
1501                         copy_v2_v2(l1_clip, l1);
1502                         ok1 = 1;
1503                 }
1504
1505                 if (BLI_rctf_isect_pt_v(rect, l2)) {
1506                         copy_v2_v2(l2_clip, l2);
1507                         ok2 = 1;
1508                 }
1509
1510                 /* line inside rect */
1511                 if (ok1 && ok2) return 1;
1512
1513                 /* top/bottom */
1514                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1515                         if (l1[1] < l2[1]) { /* line 1 is outside */
1516                                 l1_clip[0] = isect;
1517                                 l1_clip[1] = rect->ymin;
1518                                 ok1 = 1;
1519                         }
1520                         else {
1521                                 l2_clip[0] = isect;
1522                                 l2_clip[1] = rect->ymin;
1523                                 ok2 = 2;
1524                         }
1525                 }
1526
1527                 if (ok1 && ok2) return 1;
1528
1529                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1530                         if (l1[1] > l2[1]) { /* line 1 is outside */
1531                                 l1_clip[0] = isect;
1532                                 l1_clip[1] = rect->ymax;
1533                                 ok1 = 1;
1534                         }
1535                         else {
1536                                 l2_clip[0] = isect;
1537                                 l2_clip[1] = rect->ymax;
1538                                 ok2 = 2;
1539                         }
1540                 }
1541
1542                 if (ok1 && ok2) return 1;
1543
1544                 /* left/right */
1545                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1546                         if (l1[0] < l2[0]) { /* line 1 is outside */
1547                                 l1_clip[0] = rect->xmin;
1548                                 l1_clip[1] = isect;
1549                                 ok1 = 1;
1550                         }
1551                         else {
1552                                 l2_clip[0] = rect->xmin;
1553                                 l2_clip[1] = isect;
1554                                 ok2 = 2;
1555                         }
1556                 }
1557
1558                 if (ok1 && ok2) return 1;
1559
1560                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1561                         if (l1[0] > l2[0]) { /* line 1 is outside */
1562                                 l1_clip[0] = rect->xmax;
1563                                 l1_clip[1] = isect;
1564                                 ok1 = 1;
1565                         }
1566                         else {
1567                                 l2_clip[0] = rect->xmax;
1568                                 l2_clip[1] = isect;
1569                                 ok2 = 2;
1570                         }
1571                 }
1572
1573                 if (ok1 && ok2) {
1574                         return 1;
1575                 }
1576                 else {
1577                         return 0;
1578                 }
1579         }
1580 }
1581
1582
1583
1584 /* scale the quad & tri about its center
1585  * scaling by PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1586  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces */
1587 #ifndef PROJ_DEBUG_NOSEAMBLEED
1588 static void scale_quad(float insetCos[4][3], float *origCos[4], const float inset)
1589 {
1590         float cent[3];
1591         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0] + origCos[3][0]) * (1.0f / 4.0f);
1592         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1] + origCos[3][1]) * (1.0f / 4.0f);
1593         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2] + origCos[3][2]) * (1.0f / 4.0f);
1594
1595         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1596         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1597         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1598         sub_v3_v3v3(insetCos[3], origCos[3], cent);
1599
1600         mul_v3_fl(insetCos[0], inset);
1601         mul_v3_fl(insetCos[1], inset);
1602         mul_v3_fl(insetCos[2], inset);
1603         mul_v3_fl(insetCos[3], inset);
1604
1605         add_v3_v3(insetCos[0], cent);
1606         add_v3_v3(insetCos[1], cent);
1607         add_v3_v3(insetCos[2], cent);
1608         add_v3_v3(insetCos[3], cent);
1609 }
1610
1611
1612 static void scale_tri(float insetCos[4][3], float *origCos[4], const float inset)
1613 {
1614         float cent[3];
1615         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) * (1.0f / 3.0f);
1616         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) * (1.0f / 3.0f);
1617         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) * (1.0f / 3.0f);
1618
1619         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1620         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1621         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1622
1623         mul_v3_fl(insetCos[0], inset);
1624         mul_v3_fl(insetCos[1], inset);
1625         mul_v3_fl(insetCos[2], inset);
1626
1627         add_v3_v3(insetCos[0], cent);
1628         add_v3_v3(insetCos[1], cent);
1629         add_v3_v3(insetCos[2], cent);
1630 }
1631 #endif //PROJ_DEBUG_NOSEAMBLEED
1632
1633 static float len_squared_v2v2_alt(const float *v1, const float v2_1, const float v2_2)
1634 {
1635         float x, y;
1636
1637         x = v1[0] - v2_1;
1638         y = v1[1] - v2_2;
1639         return x * x + y * y;
1640 }
1641
1642 /* note, use a squared value so we can use len_squared_v2v2
1643  * be sure that you have done a bounds check first or this may fail */
1644 /* only give bucket_bounds as an arg because we need it elsewhere */
1645 static int project_bucket_isect_circle(const float cent[2], const float radius_squared, rctf *bucket_bounds)
1646 {
1647
1648         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect
1649          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1650          * this is even less work then an intersection test
1651          */
1652 #if 0
1653         if (BLI_rctf_isect_pt_v(bucket_bounds, cent))
1654                 return 1;
1655 #endif
1656
1657         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1658             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1659         {
1660                 return 1;
1661         }
1662
1663         /* out of bounds left */
1664         if (cent[0] < bucket_bounds->xmin) {
1665                 /* lower left out of radius test */
1666                 if (cent[1] < bucket_bounds->ymin) {
1667                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1668                 }
1669                 /* top left test */
1670                 else if (cent[1] > bucket_bounds->ymax) {
1671                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1672                 }
1673         }
1674         else if (cent[0] > bucket_bounds->xmax) {
1675                 /* lower right out of radius test */
1676                 if (cent[1] < bucket_bounds->ymin) {
1677                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1678                 }
1679                 /* top right test */
1680                 else if (cent[1] > bucket_bounds->ymax) {
1681                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1682                 }
1683         }
1684
1685         return 0;
1686 }
1687
1688
1689
1690 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1691  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1692  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1693  * (viewed from the side)
1694  *
1695  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1696  * funcs that only account for points inside the triangle.
1697  * however switching back to this for ortho is always an option */
1698
1699 static void rect_to_uvspace_ortho(
1700         rctf *bucket_bounds,
1701         float *v1coSS, float *v2coSS, float *v3coSS,
1702         float *uv1co, float *uv2co, float *uv3co,
1703         float bucket_bounds_uv[4][2],
1704         const int flip)
1705 {
1706         float uv[2];
1707         float w[3];
1708
1709         /* get the UV space bounding box */
1710         uv[0] = bucket_bounds->xmax;
1711         uv[1] = bucket_bounds->ymin;
1712         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1713         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1714
1715         //uv[0] = bucket_bounds->xmax; // set above
1716         uv[1] = bucket_bounds->ymax;
1717         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1718         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1719
1720         uv[0] = bucket_bounds->xmin;
1721         //uv[1] = bucket_bounds->ymax; // set above
1722         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1723         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1724
1725         //uv[0] = bucket_bounds->xmin; // set above
1726         uv[1] = bucket_bounds->ymin;
1727         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1728         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1729 }
1730
1731 /* same as above but use barycentric_weights_v2_persp */
1732 static void rect_to_uvspace_persp(
1733         rctf *bucket_bounds,
1734         float *v1coSS, float *v2coSS, float *v3coSS,
1735         float *uv1co, float *uv2co, float *uv3co,
1736         float bucket_bounds_uv[4][2],
1737         const int flip
1738         )
1739 {
1740         float uv[2];
1741         float w[3];
1742
1743         /* get the UV space bounding box */
1744         uv[0] = bucket_bounds->xmax;
1745         uv[1] = bucket_bounds->ymin;
1746         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1747         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1748
1749         //uv[0] = bucket_bounds->xmax; // set above
1750         uv[1] = bucket_bounds->ymax;
1751         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1752         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1753
1754         uv[0] = bucket_bounds->xmin;
1755         //uv[1] = bucket_bounds->ymax; // set above
1756         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1757         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1758
1759         //uv[0] = bucket_bounds->xmin; // set above
1760         uv[1] = bucket_bounds->ymin;
1761         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1762         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1763 }
1764
1765 /* This works as we need it to but we can save a few steps and not use it */
1766
1767 #if 0
1768 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
1769 {
1770         float v1[2], v2[2];
1771
1772         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
1773         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
1774
1775         return -atan2(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
1776 }
1777 #endif
1778
1779 #define ISECT_1 (1)
1780 #define ISECT_2 (1 << 1)
1781 #define ISECT_3 (1 << 2)
1782 #define ISECT_4 (1 << 3)
1783 #define ISECT_ALL3 ((1 << 3) - 1)
1784 #define ISECT_ALL4 ((1 << 4) - 1)
1785
1786 /* limit must be a fraction over 1.0f */
1787 static int IsectPT2Df_limit(float pt[2], float v1[2], float v2[2], float v3[2], float limit)
1788 {
1789         return ((area_tri_v2(pt, v1, v2) + area_tri_v2(pt, v2, v3) + area_tri_v2(pt, v3, v1)) / (area_tri_v2(v1, v2, v3))) < limit;
1790 }
1791
1792 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
1793  * so we have the clipped UV's to do pixel intersection tests with
1794  * */
1795 static int float_z_sort_flip(const void *p1, const void *p2)
1796 {
1797         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
1798 }
1799
1800 static int float_z_sort(const void *p1, const void *p2)
1801 {
1802         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
1803 }
1804
1805 static void project_bucket_clip_face(
1806         const int is_ortho,
1807         rctf *bucket_bounds,
1808         float *v1coSS, float *v2coSS, float *v3coSS,
1809         float *uv1co, float *uv2co, float *uv3co,
1810         float bucket_bounds_uv[8][2],
1811         int *tot)
1812 {
1813         int inside_bucket_flag = 0;
1814         int inside_face_flag = 0;
1815         const int flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
1816
1817         float bucket_bounds_ss[4][2];
1818
1819         /* get the UV space bounding box */
1820         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v1coSS);
1821         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v2coSS) << 1;
1822         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v3coSS) << 2;
1823
1824         if (inside_bucket_flag == ISECT_ALL3) {
1825                 /* all screenspace points are inside the bucket bounding box, this means we don't need to clip and can simply return the UVs */
1826                 if (flip) { /* facing the back? */
1827                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
1828                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1829                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
1830                 }
1831                 else {
1832                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
1833                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1834                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
1835                 }
1836
1837                 *tot = 3;
1838                 return;
1839         }
1840
1841         /* get the UV space bounding box */
1842         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
1843         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
1844         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
1845         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
1846
1847         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
1848         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
1849         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
1850
1851         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
1852         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
1853         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
1854
1855         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
1856         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
1857         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
1858
1859         if (inside_face_flag == ISECT_ALL4) {
1860                 /* bucket is totally inside the screenspace face, we can safely use weights */
1861
1862                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
1863                 else rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
1864
1865                 *tot = 4;
1866                 return;
1867         }
1868         else {
1869                 /* The Complicated Case!
1870                  *
1871                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
1872                  *
1873                  * we need to make a convex polyline from the intersection between the screenspace face
1874                  * and the bucket bounds.
1875                  *
1876                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
1877                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
1878                  * do a correct clipping on both shapes. */
1879
1880
1881                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
1882
1883
1884
1885                 /* Maximum possible 6 intersections when using a rectangle and triangle */
1886                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
1887                 float v1_clipSS[2], v2_clipSS[2];
1888                 float w[3];
1889
1890                 /* calc center */
1891                 float cent[2] = {0.0f, 0.0f};
1892                 /*float up[2] = {0.0f, 1.0f};*/
1893                 int i;
1894                 short doubles;
1895
1896                 (*tot) = 0;
1897
1898                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
1899                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
1900                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
1901                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
1902
1903                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
1904                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
1905                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
1906
1907                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
1908                         if (line_clip_rect2f(bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
1909                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
1910                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
1911                         }
1912                 }
1913
1914                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
1915                         if (line_clip_rect2f(bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
1916                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
1917                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
1918                         }
1919                 }
1920
1921                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
1922                         if (line_clip_rect2f(bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
1923                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
1924                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
1925                         }
1926                 }
1927
1928
1929                 if ((*tot) < 3) { /* no intersections to speak of */
1930                         *tot = 0;
1931                         return;
1932                 }
1933
1934                 /* now we have all points we need, collect their angles and sort them clockwise */
1935
1936                 for (i = 0; i < (*tot); i++) {
1937                         cent[0] += isectVCosSS[i][0];
1938                         cent[1] += isectVCosSS[i][1];
1939                 }
1940                 cent[0] = cent[0] / (float)(*tot);
1941                 cent[1] = cent[1] / (float)(*tot);
1942
1943
1944
1945                 /* Collect angles for every point around the center point */
1946
1947
1948 #if 0   /* uses a few more cycles then the above loop */
1949                 for (i = 0; i < (*tot); i++) {
1950                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
1951                 }
1952 #endif
1953
1954                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
1955                 v1_clipSS[1] = cent[1] + 1.0f;
1956
1957                 for (i = 0; i < (*tot); i++) {
1958                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
1959                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
1960                         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]);
1961                 }
1962
1963                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
1964                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
1965
1966                 /* remove doubles */
1967                 /* first/last check */
1968                 if (fabsf(isectVCosSS[0][0] - isectVCosSS[(*tot) - 1][0]) < PROJ_GEOM_TOLERANCE &&
1969                     fabsf(isectVCosSS[0][1] - isectVCosSS[(*tot) - 1][1]) < PROJ_GEOM_TOLERANCE)
1970                 {
1971                         (*tot)--;
1972                 }
1973
1974                 /* its possible there is only a few left after remove doubles */
1975                 if ((*tot) < 3) {
1976                         // printf("removed too many doubles A\n");
1977                         *tot = 0;
1978                         return;
1979                 }
1980
1981                 doubles = TRUE;
1982                 while (doubles == TRUE) {
1983                         doubles = FALSE;
1984                         for (i = 1; i < (*tot); i++) {
1985                                 if (fabsf(isectVCosSS[i - 1][0] - isectVCosSS[i][0]) < PROJ_GEOM_TOLERANCE &&
1986                                     fabsf(isectVCosSS[i - 1][1] - isectVCosSS[i][1]) < PROJ_GEOM_TOLERANCE)
1987                                 {
1988                                         int j;
1989                                         for (j = i + 1; j < (*tot); j++) {
1990                                                 isectVCosSS[j - 1][0] = isectVCosSS[j][0];
1991                                                 isectVCosSS[j - 1][1] = isectVCosSS[j][1];
1992                                         }
1993                                         doubles = TRUE; /* keep looking for more doubles */
1994                                         (*tot)--;
1995                                 }
1996                         }
1997                 }
1998
1999                 /* its possible there is only a few left after remove doubles */
2000                 if ((*tot) < 3) {
2001                         // printf("removed too many doubles B\n");
2002                         *tot = 0;
2003                         return;
2004                 }
2005
2006
2007                 if (is_ortho) {
2008                         for (i = 0; i < (*tot); i++) {
2009                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2010                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2011                         }
2012                 }
2013                 else {
2014                         for (i = 0; i < (*tot); i++) {
2015                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2016                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2017                         }
2018                 }
2019         }
2020
2021 #ifdef PROJ_DEBUG_PRINT_CLIP
2022         /* include this at the bottom of the above function to debug the output */
2023
2024         {
2025                 /* If there are ever any problems, */
2026                 float test_uv[4][2];
2027                 int i;
2028                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2029                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2030                 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]);
2031
2032                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2033
2034                 printf("[");
2035                 for (i = 0; i < (*tot); i++) {
2036                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2037                 }
2038                 printf("]),\\\n");
2039         }
2040 #endif
2041 }
2042
2043 /*
2044  * # This script creates faces in a blender scene from printed data above.
2045  *
2046  * project_ls = [
2047  * ...(output from above block)...
2048  * ]
2049  *
2050  * from Blender import Scene, Mesh, Window, sys, Mathutils
2051  *
2052  * import bpy
2053  *
2054  * V = Mathutils.Vector
2055  *
2056  * def main():
2057  *     sce = bpy.data.scenes.active
2058  *
2059  *     for item in project_ls:
2060  *         bb = item[0]
2061  *         uv = item[1]
2062  *         poly = item[2]
2063  *
2064  *         me = bpy.data.meshes.new()
2065  *         ob = sce.objects.new(me)
2066  *
2067  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2068  *         me.faces.extend([(0,1,2,3),])
2069  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2070  *         me.faces.extend([(4,5,6),])
2071  *
2072  *         vs = [V(p).xyz for p in poly]
2073  *         print len(vs)
2074  *         l = len(me.verts)
2075  *         me.verts.extend(vs)
2076  *
2077  *         i = l
2078  *         while i < len(me.verts):
2079  *             ii = i + 1
2080  *             if ii == len(me.verts):
2081  *                 ii = l
2082  *             me.edges.extend([i, ii])
2083  *             i += 1
2084  *
2085  * if __name__ == '__main__':
2086  *     main()
2087  */
2088
2089
2090 #undef ISECT_1
2091 #undef ISECT_2
2092 #undef ISECT_3
2093 #undef ISECT_4
2094 #undef ISECT_ALL3
2095 #undef ISECT_ALL4
2096
2097
2098 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2099  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2100 static int IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2101 {
2102         int i;
2103         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2104                 return 0;
2105
2106         for (i = 1; i < tot; i++) {
2107                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2108                         return 0;
2109
2110         }
2111
2112         return 1;
2113 }
2114 static int IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2115 {
2116         int i;
2117         int side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2118
2119         for (i = 1; i < tot; i++) {
2120                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2121                         return 0;
2122
2123         }
2124
2125         return 1;
2126 }
2127
2128 /* One of the most important function for projection painting, since it selects the pixels to be added into each bucket.
2129  * initialize pixels from this face where it intersects with the bucket_index, optionally initialize pixels for removing seams */
2130 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, const ImBuf *ibuf, const short clamp_u, const short clamp_v)
2131 {
2132         /* Projection vars, to get the 3D locations into screen space  */
2133         MemArena *arena = ps->arena_mt[thread_index];
2134         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2135         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2136
2137         const MFace *mf = ps->dm_mface + face_index;
2138         const MTFace *tf = ps->dm_mtface + face_index;
2139
2140         /* UV/pixel seeking data */
2141         int x; /* Image X-Pixel */
2142         int y; /* Image Y-Pixel */
2143         float mask;
2144         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2145
2146         int side;
2147         float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to mf->v1,2,3 or mf->v1,3,4 */
2148
2149         float *vCo[4]; /* vertex screenspace coords */
2150
2151         float w[3], wco[3];
2152
2153         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to tf->uv[0],1,2 or tf->uv[0],2,3 */
2154         float pixelScreenCo[4];
2155         bool do_3d_mapping = ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D;
2156
2157         rcti bounds_px; /* ispace bounds */
2158         /* vars for getting uvspace bounds */
2159
2160         float tf_uv_pxoffset[4][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2161         float xhalfpx, yhalfpx;
2162         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2163
2164         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2165
2166         int i1, i2, i3;
2167
2168         float uv_clip[8][2];
2169         int uv_clip_tot;
2170         const short is_ortho = ps->is_ortho;
2171         const short do_backfacecull = ps->do_backfacecull;
2172         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2173
2174         vCo[0] = ps->dm_mvert[mf->v1].co;
2175         vCo[1] = ps->dm_mvert[mf->v2].co;
2176         vCo[2] = ps->dm_mvert[mf->v3].co;
2177
2178
2179         /* Use tf_uv_pxoffset instead of tf->uv so we can offset the UV half a pixel
2180          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2181          * problems when wrapping negative coords */
2182         xhalfpx = (0.5f + (PROJ_GEOM_TOLERANCE * (1.0f / 3.0f))) / ibuf_xf;
2183         yhalfpx = (0.5f + (PROJ_GEOM_TOLERANCE * (1.0f / 4.0f))) / ibuf_yf;
2184
2185         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2186          * Needed to add this offset since UV coords are often quads aligned to pixels.
2187          * In this case pixels can be exactly between 2 triangles causing nasty
2188          * artifacts.
2189          *
2190          * This workaround can be removed and painting will still work on most cases
2191          * but since the first thing most people try is painting onto a quad- better make it work.
2192          */
2193
2194
2195
2196         tf_uv_pxoffset[0][0] = tf->uv[0][0] - xhalfpx;
2197         tf_uv_pxoffset[0][1] = tf->uv[0][1] - yhalfpx;
2198
2199         tf_uv_pxoffset[1][0] = tf->uv[1][0] - xhalfpx;
2200         tf_uv_pxoffset[1][1] = tf->uv[1][1] - yhalfpx;
2201
2202         tf_uv_pxoffset[2][0] = tf->uv[2][0] - xhalfpx;
2203         tf_uv_pxoffset[2][1] = tf->uv[2][1] - yhalfpx;
2204
2205         if (mf->v4) {
2206                 vCo[3] = ps->dm_mvert[mf->v4].co;
2207
2208                 tf_uv_pxoffset[3][0] = tf->uv[3][0] - xhalfpx;
2209                 tf_uv_pxoffset[3][1] = tf->uv[3][1] - yhalfpx;
2210                 side = 1;
2211         }
2212         else {
2213                 side = 0;
2214         }
2215
2216         do {
2217                 if (side == 1) {
2218                         i1 = 0; i2 = 2; i3 = 3;
2219                 }
2220                 else {
2221                         i1 = 0; i2 = 1; i3 = 2;
2222                 }
2223
2224                 uv1co = tf_uv_pxoffset[i1]; // was tf->uv[i1];
2225                 uv2co = tf_uv_pxoffset[i2]; // was tf->uv[i2];
2226                 uv3co = tf_uv_pxoffset[i3]; // was tf->uv[i3];
2227
2228                 v1coSS = ps->screenCoords[(*(&mf->v1 + i1))];
2229                 v2coSS = ps->screenCoords[(*(&mf->v1 + i2))];
2230                 v3coSS = ps->screenCoords[(*(&mf->v1 + i3))];
2231
2232                 /* This funtion gives is a concave polyline in UV space from the clipped quad and tri*/
2233                 project_bucket_clip_face(
2234                         is_ortho, bucket_bounds,
2235                         v1coSS, v2coSS, v3coSS,
2236                         uv1co, uv2co, uv3co,
2237                         uv_clip, &uv_clip_tot
2238                         );
2239
2240                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2241 #if 0
2242                 if (uv_clip_tot > 6) {
2243                         printf("this should never happen! %d\n", uv_clip_tot);
2244                 }
2245 #endif
2246
2247                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2248
2249                         if (clamp_u) {
2250                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2251                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2252                         }
2253
2254                         if (clamp_v) {
2255                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2256                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2257                         }
2258
2259                         /* clip face and */
2260
2261                         has_isect = 0;
2262                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2263                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2264                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2265
2266                                 has_x_isect = 0;
2267                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2268                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2269                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2270
2271                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2272                                          * could check the poly direction but better to do this */
2273                                         if ((do_backfacecull == TRUE  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2274                                             (do_backfacecull == FALSE && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2275                                         {
2276
2277                                                 has_x_isect = has_isect = 1;
2278
2279                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2280                                                 else          screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2281
2282                                                 /* a pity we need to get the worldspace pixel location here */
2283                                                 if (do_clip || do_3d_mapping) {
2284                                                         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);
2285                                                         if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2286                                                                 continue; /* Watch out that no code below this needs to run */
2287                                                         }
2288                                                 }
2289
2290                                                 /* Is this UV visible from the view? - raytrace */
2291                                                 /* project_paint_PickFace is less complex, use for testing */
2292                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == face_index) {
2293                                                 if ((ps->do_occlude == FALSE) ||
2294                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2295                                                 {
2296                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2297
2298                                                         if (mask > 0.0f) {
2299                                                                 BLI_linklist_prepend_arena(
2300                                                                         bucketPixelNodes,
2301                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index,
2302                                                                                                    image_index, pixelScreenCo, wco, side, w),
2303                                                                         arena
2304                                                                         );
2305                                                         }
2306                                                 }
2307
2308                                         }
2309 //#if 0
2310                                         else if (has_x_isect) {
2311                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2312                                                 break;
2313                                         }
2314 //#endif
2315                                 }
2316
2317
2318 #if 0           /* TODO - investigate why this dosnt work sometimes! it should! */
2319                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2320                                 if (has_x_isect == 0 && has_isect) {
2321                                         break;
2322                                 }
2323 #endif
2324                         }
2325                 }
2326         } while (side--);
2327
2328
2329
2330 #ifndef PROJ_DEBUG_NOSEAMBLEED
2331         if (ps->seam_bleed_px > 0.0f) {
2332                 int face_seam_flag;
2333
2334                 if (ps->thread_tot > 1)
2335                         BLI_lock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2336
2337                 face_seam_flag = ps->faceSeamFlags[face_index];
2338
2339                 /* are any of our edges un-initialized? */
2340                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_NOSEAM1)) == 0 ||
2341                     (face_seam_flag & (PROJ_FACE_SEAM2 | PROJ_FACE_NOSEAM2)) == 0 ||
2342                     (face_seam_flag & (PROJ_FACE_SEAM3 | PROJ_FACE_NOSEAM3)) == 0 ||
2343                     (face_seam_flag & (PROJ_FACE_SEAM4 | PROJ_FACE_NOSEAM4)) == 0)
2344                 {
2345                         project_face_seams_init(ps, face_index, mf->v4);
2346                         face_seam_flag = ps->faceSeamFlags[face_index];
2347                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3, flag&PROJ_FACE_SEAM4);
2348                 }
2349
2350                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_SEAM2 | PROJ_FACE_SEAM3 | PROJ_FACE_SEAM4)) == 0) {
2351
2352                         if (ps->thread_tot > 1)
2353                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2354
2355                 }
2356                 else {
2357                         /* we have a seam - deal with it! */
2358
2359                         /* Now create new UV's for the seam face */
2360                         float (*outset_uv)[2] = ps->faceSeamUVs[face_index];
2361                         float insetCos[4][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2362
2363                         float *vCoSS[4]; /* vertex screenspace coords */
2364
2365                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2366                         float edge_verts_inset_clip[2][3];
2367                         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 */
2368
2369                         float seam_subsection[4][2];
2370                         float fac1, fac2, ftot;
2371
2372
2373                         if (outset_uv[0][0] == FLT_MAX) /* first time initialize */
2374                                 uv_image_outset(tf_uv_pxoffset, outset_uv, ps->seam_bleed_px, ibuf->x, ibuf->y, mf->v4);
2375
2376                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2377                         if (ps->thread_tot > 1)
2378                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2379
2380                         vCoSS[0] = ps->screenCoords[mf->v1];
2381                         vCoSS[1] = ps->screenCoords[mf->v2];
2382                         vCoSS[2] = ps->screenCoords[mf->v3];
2383                         if (mf->v4)
2384                                 vCoSS[3] = ps->screenCoords[mf->v4];
2385
2386                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2387                         if (is_ortho) {
2388                                 if (mf->v4) scale_quad(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2389                                 else        scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2390                         }
2391                         else {
2392                                 if (mf->v4) scale_quad(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2393                                 else        scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2394                         }
2395
2396                         side = 0; /* for triangles this wont need to change */
2397
2398                         for (fidx1 = 0; fidx1 < (mf->v4 ? 4 : 3); fidx1++) {
2399                                 if (mf->v4) fidx2 = (fidx1 == 3) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2,3) -> (1,2,3,0) */
2400                                 else        fidx2 = (fidx1 == 2) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2) -> (1,2,0) */
2401
2402                                 if ((face_seam_flag & (1 << fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2403                                     line_clip_rect2f(bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1]))
2404                                 {
2405
2406                                         ftot = len_v2v2(vCoSS[fidx1], vCoSS[fidx2]); /* screenspace edge length */
2407
2408                                         if (ftot > 0.0f) { /* avoid div by zero */
2409                                                 if (mf->v4) {
2410                                                         if (fidx1 == 2 || fidx2 == 2) side = 1;
2411                                                         else side = 0;
2412                                                 }
2413
2414                                                 fac1 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[0]) / ftot;
2415                                                 fac2 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[1]) / ftot;
2416
2417                                                 interp_v2_v2v2(seam_subsection[0], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac1);
2418                                                 interp_v2_v2v2(seam_subsection[1], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac2);
2419
2420                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2421                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2422
2423                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2424                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2425                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2426                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2427
2428
2429                                                 if (pixel_bounds_uv(seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3], &bounds_px, ibuf->x, ibuf->y, 1)) {
2430                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2431
2432                                                         has_isect = 0;
2433                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2434                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2435                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2436
2437                                                                 has_x_isect = 0;
2438                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2439                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2440                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2441
2442                                                                         /* test we're inside uvspace bucket and triangle bounds */
2443                                                                         if (isect_point_quad_v2(uv, seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3])) {
2444                                                                                 float fac;
2445
2446                                                                                 /* We need to find the closest point along the face edge,
2447                                                                                  * getting the screen_px_from_*** wont work because our actual location
2448                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2449                                                                                  * our location on the side of the face's UV */
2450 #if 0
2451                                                                                 if (is_ortho) screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2452                                                                                 else          screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2453 #endif
2454
2455                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2456                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2457
2458                                                                                 fac = line_point_factor_v2(uv, seam_subsection[0], seam_subsection[1]);
2459                                                                                 if      (fac < 0.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[0]); }
2460                                                                                 else if (fac > 1.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[1]); }
2461                                                                                 else                 { interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac); }
2462
2463                                                                                 if (!is_ortho) {
2464                                                                                         pixelScreenCo[3] = 1.0f;
2465                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2466                                                                                         pixelScreenCo[0] = (float)(ps->winx * 0.5f) + (ps->winx * 0.5f) * pixelScreenCo[0] / pixelScreenCo[3];
2467                                                                                         pixelScreenCo[1] = (float)(ps->winy * 0.5f) + (ps->winy * 0.5f) * pixelScreenCo[1] / pixelScreenCo[3];
2468                                                                                         pixelScreenCo[2] = pixelScreenCo[2] / pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2469                                                                                 }
2470
2471                                                                                 if ((ps->do_occlude == FALSE) ||
2472                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2473                                                                                 {
2474                                                                                         /* Only bother calculating the weights if we intersect */
2475                                                                                         if (ps->do_mask_normal || ps->dm_mtface_clone) {
2476 #if 1
2477                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2478                                                                                                 float uv_close[2];
2479                                                                                                 float uv_fac = closest_to_line_v2(uv_close, uv, tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2]);
2480                                                                                                 if      (uv_fac < 0.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx1]);
2481                                                                                                 else if (uv_fac > 1.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx2]);
2482
2483                                                                                                 if (side) {
2484                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[2], tf_uv_pxoffset[3], uv_close, w);
2485                                                                                                 }
2486                                                                                                 else {
2487                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[1], tf_uv_pxoffset[2], uv_close, w);
2488                                                                                                 }
2489 #else                                                                                   /* this is buggy with quads, don't use for now */
2490
2491                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2492                                                                                                 uv_fac = fac1 + (uv_fac * (fac2 - fac1));
2493
2494                                                                                                 w[0] = w[1] = w[2] = 0.0;
2495                                                                                                 if (side) {
2496                                                                                                         w[fidx1 ? fidx1 - 1 : 0] = 1.0f - uv_fac;
2497                                                                                                         w[fidx2 ? fidx2 - 1 : 0] = uv_fac;
2498                                                                                                 }
2499                                                                                                 else {
2500                                                                                                         w[fidx1] = 1.0f - uv_fac;
2501                                                                                                         w[fidx2] = uv_fac;
2502                                                                                                 }
2503 #endif
2504                                                                                         }
2505
2506                                                                                         /* a pity we need to get the worldspace pixel location here */
2507                                                                                         if (do_clip || do_3d_mapping) {
2508                                                                                                 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);
2509                                                                                                 else      interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
2510
2511                                                                                                 if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2512                                                                                                         continue; /* Watch out that no code below this needs to run */
2513                                                                                                 }
2514                                                                                         }
2515
2516                                                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2517
2518                                                                                         if (mask > 0.0f) {
2519                                                                                                 BLI_linklist_prepend_arena(
2520                                                                                                         bucketPixelNodes,
2521                                                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index, image_index, pixelScreenCo, wco, side, w),
2522                                                                                                         arena
2523                                                                                                         );
2524                                                                                         }
2525
2526                                                                                 }
2527                                                                         }
2528                                                                         else if (has_x_isect) {
2529                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2530                                                                                 break;
2531                                                                         }
2532                                                                 }
2533
2534 #if 0                           /* TODO - investigate why this dosnt work sometimes! it should! */
2535                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2536                                                                 if (has_x_isect == 0 && has_isect) {
2537                                                                         break;
2538                                                                 }
2539 #endif
2540                                                         }
2541                                                 }
2542                                         }
2543                                 }
2544                         }
2545                 }
2546         }
2547 #endif // PROJ_DEBUG_NOSEAMBLEED
2548 }
2549
2550
2551 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2552 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2553 {
2554         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2555         /* 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 */
2556         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 */
2557         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2558
2559         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2560         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2561
2562         /* in case the rect is outside the mesh 2d bounds */
2563         CLAMP(bucketMin[0], 0, ps->buckets_x);
2564         CLAMP(bucketMin[1], 0, ps->buckets_y);
2565
2566         CLAMP(bucketMax[0], 0, ps->buckets_x);
2567         CLAMP(bucketMax[1], 0, ps->buckets_y);
2568 }
2569
2570 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2571 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2572 {
2573         bucket_bounds->xmin = ps->screenMin[0] + ((bucket_x) * (ps->screen_width / ps->buckets_x));     /* left */
2574         bucket_bounds->xmax = ps->screenMin[0] + ((bucket_x + 1) * (ps->screen_width / ps->buckets_x)); /* right */
2575
2576         bucket_bounds->ymin = ps->screenMin[1] + ((bucket_y) * (ps->screen_height / ps->buckets_y));      /* bottom */
2577         bucket_bounds->ymax = ps->screenMin[1] + ((bucket_y + 1) * (ps->screen_height  / ps->buckets_y)); /* top */
2578 }
2579
2580 /* Fill this bucket with pixels from the faces that intersect it.
2581  *
2582  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2583 static void project_bucket_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, rctf *bucket_bounds)
2584 {
2585         LinkNode *node;
2586         int face_index, image_index = 0;
2587         ImBuf *ibuf = NULL;
2588         Image *tpage_last = NULL, *tpage;
2589         Image *ima = NULL;
2590
2591         if (ps->image_tot == 1) {
2592                 /* Simple loop, no context switching */
2593                 ibuf = ps->projImages[0].ibuf;
2594                 ima = ps->projImages[0].ima;
2595
2596                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2597                         project_paint_face_init(ps, thread_index, bucket_index, GET_INT_FROM_POINTER(node->link), 0, bucket_bounds, ibuf, ima->tpageflag & IMA_CLAMP_U, ima->tpageflag & IMA_CLAMP_V);
2598                 }
2599         }
2600         else {
2601
2602                 /* More complicated loop, switch between images */
2603                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2604                         face_index = GET_INT_FROM_POINTER(node->link);
2605
2606                         /* Image context switching */
2607                         tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
2608                         if (tpage_last != tpage) {
2609                                 tpage_last = tpage;
2610
2611                                 for (image_index = 0; image_index < ps->image_tot; image_index++) {
2612                                         if (ps->projImages[image_index].ima == tpage_last) {
2613                                                 ibuf = ps->projImages[image_index].ibuf;
2614                                                 ima = ps->projImages[image_index].ima;
2615                                                 break;
2616                                         }
2617                                 }
2618                         }
2619                         /* context switching done */
2620
2621                         project_paint_face_init(ps, thread_index, bucket_index, face_index, image_index, bucket_bounds, ibuf, ima->tpageflag & IMA_CLAMP_U, ima->tpageflag & IMA_CLAMP_V);
2622                 }
2623         }
2624
2625         ps->bucketFlags[bucket_index] |= PROJ_BUCKET_INIT;
2626 }
2627
2628
2629 /* We want to know if a bucket and a face overlap in screen-space
2630  *
2631  * Note, if this ever returns false positives its not that bad, since a face in the bounding area will have its pixels
2632  * calculated when it might not be needed later, (at the moment at least)
2633  * obviously it shouldn't have bugs though */
2634
2635 static int project_bucket_face_isect(ProjPaintState *ps, int bucket_x, int bucket_y, const MFace *mf)
2636 {
2637         /* TODO - replace this with a tricker method that uses sideofline for all screenCoords's edges against the closest bucket corner */
2638         rctf bucket_bounds;
2639         float p1[2], p2[2], p3[2], p4[2];
2640         float *v, *v1, *v2, *v3, *v4 = NULL;
2641         int fidx;
2642
2643         project_bucket_bounds(ps, bucket_x, bucket_y, &bucket_bounds);
2644
2645         /* Is one of the faces verts in the bucket bounds? */
2646
2647         fidx = mf->v4 ? 3 : 2;
2648         do {
2649                 v = ps->screenCoords[(*(&mf->v1 + fidx))];
2650                 if (BLI_rctf_isect_pt_v(&bucket_bounds, v)) {
2651                         return 1;
2652                 }
2653         } while (fidx--);
2654
2655         v1 = ps->screenCoords[mf->v1];
2656         v2 = ps->screenCoords[mf->v2];
2657         v3 = ps->screenCoords[mf->v3];
2658         if (mf->v4) {
2659                 v4 = ps->screenCoords[mf->v4];
2660         }
2661
2662         p1[0] = bucket_bounds.xmin; p1[1] = bucket_bounds.ymin;
2663         p2[0] = bucket_bounds.xmin; p2[1] = bucket_bounds.ymax;
2664         p3[0] = bucket_bounds.xmax; p3[1] = bucket_bounds.ymax;
2665         p4[0] = bucket_bounds.xmax; p4[1] = bucket_bounds.ymin;
2666
2667         if (mf->v4) {
2668                 if (isect_point_quad_v2(p1, v1, v2, v3, v4) ||
2669                     isect_point_quad_v2(p2, v1, v2, v3, v4) ||
2670                     isect_point_quad_v2(p3, v1, v2, v3, v4) ||
2671                     isect_point_quad_v2(p4, v1, v2, v3, v4) ||
2672
2673                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2674                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3) || isect_line_line_v2(p1, p2, v3, v4)) ||
2675                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3) || isect_line_line_v2(p2, p3, v3, v4)) ||
2676                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3) || isect_line_line_v2(p3, p4, v3, v4)) ||
2677                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3) || isect_line_line_v2(p4, p1, v3, v4)))
2678                 {
2679                         return 1;
2680                 }
2681         }
2682         else {
2683                 if (isect_point_tri_v2(p1, v1, v2, v3) ||
2684                     isect_point_tri_v2(p2, v1, v2, v3) ||
2685                     isect_point_tri_v2(p3, v1, v2, v3) ||
2686                     isect_point_tri_v2(p4, v1, v2, v3) ||
2687                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2688                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3)) ||
2689                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3)) ||
2690                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3)) ||
2691                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3)))
2692                 {
2693                         return 1;
2694                 }
2695         }
2696
2697         return 0;
2698 }
2699
2700 /* Add faces to the bucket but don't initialize its pixels
2701  * TODO - when painting occluded, sort the faces on their min-Z and only add faces that faces that are not occluded */
2702 static void project_paint_delayed_face_init(ProjPaintState *ps, const MFace *mf, const int face_index)
2703 {
2704         float min[2], max[2], *vCoSS;
2705         int bucketMin[2], bucketMax[2]; /* for  ps->bucketRect indexing */
2706         int fidx, bucket_x, bucket_y;
2707         int has_x_isect = -1, has_isect = 0; /* for early loop exit */
2708         MemArena *arena = ps->arena_mt[0]; /* just use the first thread arena since threading has not started yet */
2709
2710         INIT_MINMAX2(min, max);
2711
2712         fidx = mf->v4 ? 3 : 2;
2713         do {
2714                 vCoSS = ps->screenCoords[*(&mf->v1 + fidx)];
2715                 minmax_v2v2_v2(min, max, vCoSS);
2716         } while (fidx--);
2717
2718         project_paint_bucket_bounds(ps, min, max, bucketMin, bucketMax);
2719
2720         for (bucket_y = bucketMin[1]; bucket_y < bucketMax[1]; bucket_y++) {
2721                 has_x_isect = 0;
2722                 for (bucket_x = bucketMin[0]; bucket_x < bucketMax[0]; bucket_x++) {
2723                         if (project_bucket_face_isect(ps, bucket_x, bucket_y, mf)) {
2724                                 int bucket_index = bucket_x + (bucket_y * ps->buckets_x);
2725                                 BLI_linklist_prepend_arena(
2726                                         &ps->bucketFaces[bucket_index],
2727                                         SET_INT_IN_POINTER(face_index), /* cast to a pointer to shut up the compiler */
2728                                         arena
2729                                         );
2730
2731                                 has_x_isect = has_isect = 1;
2732                         }
2733                         else if (has_x_isect) {
2734                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2735                                 break;
2736                         }
2737                 }
2738
2739                 /* no intersection for this entire row, after some intersection above means we can quit now */
2740                 if (has_x_isect == 0 && has_isect) {
2741                         break;
2742                 }
2743         }
2744
2745 #ifndef PROJ_DEBUG_NOSEAMBLEED
2746         if (ps->seam_bleed_px > 0.0f) {
2747                 if (!mf->v4) {
2748                         ps->faceSeamFlags[face_index] |= PROJ_FACE_NOSEAM4; /* so this wont show up as an untagged edge */
2749                 }
2750                 **ps->faceSeamUVs[face_index] = FLT_MAX; /* set as uninitialized */
2751         }
2752 #endif
2753 }
2754
2755 /* run once per stroke before projection painting */
2756 static void project_paint_begin(ProjPaintState *ps)
2757 {
2758         /* Viewport vars */
2759         float mat[3][3];
2760
2761         float no[3];
2762
2763         float *projScreenCo; /* Note, we could have 4D vectors are only needed for */
2764         float projMargin;
2765
2766         /* Image Vars - keep track of images we have used */
2767         LinkNode *image_LinkList = NULL;
2768         LinkNode *node;
2769
2770         ProjPaintImage *projIma;
2771         Image *tpage_last = NULL, *tpage;
2772
2773         /* Face vars */
2774         MFace *mf;
2775         MTFace *tf;
2776
2777         int a, i; /* generic looping vars */
2778         int image_index = -1, face_index;
2779         MVert *mv;
2780
2781         MemArena *arena; /* at the moment this is just ps->arena_mt[0], but use this to show were not multithreading */
2782
2783         const int diameter = 2 * BKE_brush_size_get(ps->scene, ps->brush);
2784
2785         /* ---- end defines ---- */
2786
2787         if (ps->source == PROJ_SRC_VIEW)
2788                 ED_view3d_clipping_local(ps->rv3d, ps->ob->obmat);  /* faster clipping lookups */
2789
2790         /* paint onto the derived mesh */
2791
2792         /* Workaround for subsurf selection, try the display mesh first */
2793         if (ps->source == PROJ_SRC_IMAGE_CAM) {
2794                 /* using render mesh, assume only camera was rendered from */
2795                 ps->dm = mesh_create_derived_render(ps->scene, ps->ob, ps->scene->customdata_mask | CD_MASK_MTFACE);
2796                 ps->dm_release = TRUE;
2797         }
2798         else if (ps->ob->derivedFinal && CustomData_has_layer(&ps->ob->derivedFinal->faceData, CD_MTFACE)) {
2799                 ps->dm = ps->ob->derivedFinal;
2800                 ps->dm_release = FALSE;
2801         }
2802         else {
2803                 ps->dm = mesh_get_derived_final(ps->scene, ps->ob, ps->scene->customdata_mask | CD_MASK_MTFACE);
2804                 ps->dm_release = TRUE;
2805         }
2806
2807         if (!CustomData_has_layer(&ps->dm->faceData, CD_MTFACE) ) {
2808
2809                 if (ps->dm_release)
2810                         ps->dm->release(ps->dm);
2811
2812                 ps->dm = NULL;
2813                 return;
2814         }
2815
2816         ps->dm_mvert = ps->dm->getVertArray(ps->dm);
2817         ps->dm_mface = ps->dm->getTessFaceArray(ps->dm);
2818         ps->dm_mtface = ps->dm->getTessFaceDataArray(ps->dm, CD_MTFACE);
2819
2820         ps->dm_totvert = ps->dm->getNumVerts(ps->dm);
2821         ps->dm_totface = ps->dm->getNumTessFaces(ps->dm);
2822
2823         /* use clone mtface? */
2824
2825
2826         /* Note, use the original mesh for getting the clone and mask layer index
2827          * this avoids re-generating the derived mesh just to get the new index */
2828         if (ps->do_layer_clone) {
2829                 //int layer_num = CustomData_get_clone_layer(&ps->dm->faceData, CD_MTFACE);
2830                 int layer_num = CustomData_get_clone_layer(&((Mesh *)ps->ob->data)->fdata, CD_MTFACE);
2831                 if (layer_num != -1)
2832                         ps->dm_mtface_clone = CustomData_get_layer_n(&ps->dm->faceData, CD_MTFACE, layer_num);
2833
2834                 if (ps->dm_mtface_clone == NULL || ps->dm_mtface_clone == ps->dm_mtface) {
2835                         ps->do_layer_clone = FALSE;
2836                         ps->dm_mtface_clone = NULL;
2837                         printf("ACK!\n");
2838                 }
2839         }
2840
2841         if (ps->do_layer_stencil) {
2842                 //int layer_num = CustomData_get_stencil_layer(&ps->dm->faceData, CD_MTFACE);
2843                 int layer_num = CustomData_get_stencil_layer(&((Mesh *)ps->ob->data)->fdata, CD_MTFACE);
2844                 if (layer_num != -1)
2845                         ps->dm_mtface_stencil = CustomData_get_layer_n(&ps->dm->faceData, CD_MTFACE, layer_num);
2846
2847                 if (ps->dm_mtface_stencil == NULL || ps->dm_mtface_stencil == ps->dm_mtface) {
2848                         ps->do_layer_stencil = FALSE;
2849                         ps->dm_mtface_stencil = NULL;
2850                 }
2851         }
2852
2853         /* when using subsurf or multires, mface arrays are thrown away, we need to keep a copy */
2854         if (ps->dm->type != DM_TYPE_CDDM) {
2855                 ps->dm_mvert = MEM_dupallocN(ps->dm_mvert);
2856                 ps->dm_mface = MEM_dupallocN(ps->dm_mface);
2857                 /* looks like these are ok for now.*/
2858 #if 0
2859                 ps->dm_mtface = MEM_dupallocN(ps->dm_mtface);
2860                 ps->dm_mtface_clone = MEM_dupallocN(ps->dm_mtface_clone);
2861                 ps->dm_mtface_stencil = MEM_dupallocN(ps->dm_mtface_stencil);
2862 #endif
2863         }
2864
2865         ps->viewDir[0] = 0.0f;
2866         ps->viewDir[1] = 0.0f;
2867         ps->viewDir[2] = 1.0f;
2868
2869         {
2870                 float viewmat[4][4];
2871                 float viewinv[4][4];
2872
2873                 invert_m4_m4(ps->ob->imat, ps->ob->obmat);
2874
2875                 if (ps->source == PROJ_SRC_VIEW) {
2876                         /* normal drawing */
2877                         ps->winx = ps->ar->winx;
2878                         ps->winy = ps->ar->winy;
2879
2880                         copy_m4_m4(viewmat, ps->rv3d->viewmat);
2881                         copy_m4_m4(viewinv, ps->rv3d->viewinv);
2882
2883                         ED_view3d_ob_project_mat_get(ps->rv3d, ps->ob, ps->projectMat);
2884