Image paint: 2D painting now supports texture masks and does masking more
[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;
252 #ifndef PROJ_DEBUG_NOSEAMBLEED
253         float seam_bleed_px;
254 #endif
255         /* clone vars */
256         float cloneOffset[2];
257
258         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
259         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
260         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
261         float clipsta, clipend;
262
263         /* reproject vars */
264         Image *reproject_image;
265         ImBuf *reproject_ibuf;
266
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 } ProjPaintState;
274
275 typedef union pixelPointer {
276         float *f_pt;            /* float buffer */
277         unsigned int *uint_pt; /* 2 ways to access a char buffer */
278         unsigned char *ch_pt;
279 } PixelPointer;
280
281 typedef union pixelStore {
282         unsigned char ch[4];
283         unsigned int uint;
284         float f[4];
285 } PixelStore;
286
287 typedef struct ProjPixel {
288         float projCoSS[2]; /* the floating point screen projection of this pixel */
289         float worldCoSS[3];
290         /* Only used when the airbrush is disabled.
291          * Store the max mask value to avoid painting over an area with a lower opacity
292          * with an advantage that we can avoid touching the pixel at all, if the
293          * new mask value is lower then mask_accum */
294         unsigned short mask_accum;
295
296         /* for various reasons we may want to mask out painting onto this pixel */
297         unsigned short mask;
298
299         short x_px, y_px;
300
301         PixelStore origColor;
302         PixelStore newColor;
303         PixelPointer pixel;
304
305         short image_index; /* if anyone wants to paint onto more than 32768 images they can bite me */
306         unsigned char bb_cell_index;
307 } ProjPixel;
308
309 typedef struct ProjPixelClone {
310         struct ProjPixel __pp;
311         PixelStore clonepx;
312 } ProjPixelClone;
313
314 /* blur, store surrounding colors */
315 #define PROJ_PIXEL_SOFTEN_TOT 4
316 /* blur picking offset (in screenspace) */
317 #define PROJ_PIXEL_SOFTEN_OFS_PX 1.0f
318
319 static const float proj_pixel_soften_v2[PROJ_PIXEL_SOFTEN_TOT][2] = {
320         {-PROJ_PIXEL_SOFTEN_OFS_PX,                         0.0f},
321         { 0.0f,                        -PROJ_PIXEL_SOFTEN_OFS_PX},
322         { 0.0f,                         PROJ_PIXEL_SOFTEN_OFS_PX},
323         { PROJ_PIXEL_SOFTEN_OFS_PX,                         0.0f},
324 };
325
326 /* Finish projection painting structs */
327
328 static Image *project_paint_face_image(const ProjPaintState *ps, MTFace *dm_mtface, int face_index)
329 {
330         Image *ima;
331
332         if (ps->do_new_shading_nodes) { /* cached BKE_scene_use_new_shading_nodes result */
333                 MFace *mf = ps->dm_mface + face_index;
334                 ED_object_get_active_image(ps->ob, mf->mat_nr + 1, &ima, NULL, NULL);
335         }
336         else {
337                 ima = dm_mtface[face_index].tpage;
338         }
339
340         return ima;
341 }
342
343 /* fast projection bucket array lookup, use the safe version for bound checking  */
344 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
345 {
346         /* If we were not dealing with screenspace 2D coords we could simple do...
347          * ps->bucketRect[x + (y*ps->buckets_y)] */
348
349         /* please explain?
350          * projCoSS[0] - ps->screenMin[0]   : zero origin
351          * ... / ps->screen_width           : range from 0.0 to 1.0
352          * ... * ps->buckets_x              : use as a bucket index
353          *
354          * Second multiplication does similar but for vertical offset
355          */
356         return ( (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
357                (((int)(((projCoSS[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
358 }
359
360 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
361 {
362         int bucket_index = project_bucket_offset(ps, projCoSS);
363
364         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
365                 return -1;
366         }
367         else {
368                 return bucket_index;
369         }
370 }
371
372 /* still use 2D X,Y space but this works for verts transformed by a perspective matrix, using their 4th component as a weight */
373 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])
374 {
375         float wtot_inv, wtot;
376
377         w[0] = area_tri_signed_v2(v2, v3, co) / v1[3];
378         w[1] = area_tri_signed_v2(v3, v1, co) / v2[3];
379         w[2] = area_tri_signed_v2(v1, v2, co) / v3[3];
380         wtot = w[0] + w[1] + w[2];
381
382         if (wtot != 0.0f) {
383                 wtot_inv = 1.0f / wtot;
384
385                 w[0] = w[0] * wtot_inv;
386                 w[1] = w[1] * wtot_inv;
387                 w[2] = w[2] * wtot_inv;
388         }
389         else /* dummy values for zero area face */
390                 w[0] = w[1] = w[2] = 1.0f / 3.0f;
391 }
392
393 static float VecZDepthOrtho(const float pt[2],
394                             const float v1[3], const float v2[3], const float v3[3],
395                             float w[3])
396 {
397         barycentric_weights_v2(v1, v2, v3, pt, w);
398         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
399 }
400
401 static float VecZDepthPersp(const float pt[2],
402                             const float v1[4], const float v2[4], const float v3[4],
403                             float w[3])
404 {
405         float wtot_inv, wtot;
406         float w_tmp[3];
407
408         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
409         /* for the depth we need the weights to match what
410          * barycentric_weights_v2 would return, in this case its easiest just to
411          * undo the 4th axis division and make it unit-sum
412          *
413          * don't call barycentric_weights_v2() because our callers expect 'w'
414          * to be weighted from the perspective */
415         w_tmp[0] = w[0] * v1[3];
416         w_tmp[1] = w[1] * v2[3];
417         w_tmp[2] = w[2] * v3[3];
418
419         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
420
421         if (wtot != 0.0f) {
422                 wtot_inv = 1.0f / wtot;
423
424                 w_tmp[0] = w_tmp[0] * wtot_inv;
425                 w_tmp[1] = w_tmp[1] * wtot_inv;
426                 w_tmp[2] = w_tmp[2] * wtot_inv;
427         }
428         else /* dummy values for zero area face */
429                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
430         /* done mimicing barycentric_weights_v2() */
431
432         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
433 }
434
435
436 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
437 static int project_paint_PickFace(const ProjPaintState *ps, const float pt[2], float w[3], int *side)
438 {
439         LinkNode *node;
440         float w_tmp[3];
441         float *v1, *v2, *v3, *v4;
442         int bucket_index;
443         int face_index;
444         int best_side = -1;
445         int best_face_index = -1;
446         float z_depth_best = FLT_MAX, z_depth;
447         MFace *mf;
448
449         bucket_index = project_bucket_offset_safe(ps, pt);
450         if (bucket_index == -1)
451                 return -1;
452
453
454
455         /* we could return 0 for 1 face buckets, as long as this function assumes
456          * that the point its testing is only every originated from an existing face */
457
458         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
459                 face_index = GET_INT_FROM_POINTER(node->link);
460                 mf = ps->dm_mface + face_index;
461
462                 v1 = ps->screenCoords[mf->v1];
463                 v2 = ps->screenCoords[mf->v2];
464                 v3 = ps->screenCoords[mf->v3];
465
466                 if (isect_point_tri_v2(pt, v1, v2, v3)) {
467                         if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v2, v3, w_tmp);
468                         else z_depth = VecZDepthPersp(pt, v1, v2, v3, w_tmp);
469
470                         if (z_depth < z_depth_best) {
471                                 best_face_index = face_index;
472                                 best_side = 0;
473                                 z_depth_best = z_depth;
474                                 copy_v3_v3(w, w_tmp);
475                         }
476                 }
477                 else if (mf->v4) {
478                         v4 = ps->screenCoords[mf->v4];
479
480                         if (isect_point_tri_v2(pt, v1, v3, v4)) {
481                                 if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v3, v4, w_tmp);
482                                 else z_depth = VecZDepthPersp(pt, v1, v3, v4, w_tmp);
483
484                                 if (z_depth < z_depth_best) {
485                                         best_face_index = face_index;
486                                         best_side = 1;
487                                         z_depth_best = z_depth;
488                                         copy_v3_v3(w, w_tmp);
489                                 }
490                         }
491                 }
492         }
493
494         *side = best_side;
495         return best_face_index; /* will be -1 or a valid face */
496 }
497
498 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
499 static void uvco_to_wrapped_pxco(const float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
500 {
501         /* use */
502         *x = (float)fmodf(uv[0], 1.0f);
503         *y = (float)fmodf(uv[1], 1.0f);
504
505         if (*x < 0.0f) *x += 1.0f;
506         if (*y < 0.0f) *y += 1.0f;
507
508         *x = *x * ibuf_x - 0.5f;
509         *y = *y * ibuf_y - 0.5f;
510 }
511
512 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
513 static int project_paint_PickColor(const ProjPaintState *ps, const float pt[2],
514                                    float *rgba_fp, unsigned char *rgba, const int interp)
515 {
516         float w[3], uv[2];
517         int side;
518         int face_index;
519         MTFace *tf;
520         Image *ima;
521         ImBuf *ibuf;
522         int xi, yi;
523
524
525         face_index = project_paint_PickFace(ps, pt, w, &side);
526
527         if (face_index == -1)
528                 return 0;
529
530         tf = ps->dm_mtface + face_index;
531
532         if (side == 0) {
533                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[1], tf->uv[2], w);
534         }
535         else { /* QUAD */
536                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[2], tf->uv[3], w);
537         }
538
539         ima = project_paint_face_image(ps, ps->dm_mtface, face_index);
540         ibuf = ima->ibufs.first; /* we must have got the imbuf before getting here */
541         if (!ibuf) return 0;
542
543         if (interp) {
544                 float x, y;
545                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
546
547                 if (ibuf->rect_float) {
548                         if (rgba_fp) {
549                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
550                         }
551                         else {
552                                 float rgba_tmp_f[4];
553                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
554                                 premul_float_to_straight_uchar(rgba, rgba_tmp_f);
555                         }
556                 }
557                 else {
558                         if (rgba) {
559                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
560                         }
561                         else {
562                                 unsigned char rgba_tmp[4];
563                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
564                                 straight_uchar_to_premul_float(rgba_fp, rgba_tmp);
565                         }
566                 }
567         }
568         else {
569                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
570                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
571                 //if (xi < 0 || xi >= ibuf->x  ||  yi < 0 || yi >= ibuf->y) return 0;
572
573                 /* wrap */
574                 xi = ((int)(uv[0] * ibuf->x)) % ibuf->x;
575                 if (xi < 0) xi += ibuf->x;
576                 yi = ((int)(uv[1] * ibuf->y)) % ibuf->y;
577                 if (yi < 0) yi += ibuf->y;
578
579
580                 if (rgba) {
581                         if (ibuf->rect_float) {
582                                 float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
583                                 premul_float_to_straight_uchar(rgba, rgba_tmp_fp);
584                         }
585                         else {
586                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
587                         }
588                 }
589
590                 if (rgba_fp) {
591                         if (ibuf->rect_float) {
592                                 copy_v4_v4(rgba_fp, (ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
593                         }
594                         else {
595                                 unsigned char *tmp_ch = ((unsigned char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
596                                 straight_uchar_to_premul_float(rgba_fp, tmp_ch);
597                         }
598                 }
599         }
600         return 1;
601 }
602
603 /* Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusuion test)
604  * return...
605  *  0   : no occlusion
606  * -1   : no occlusion but 2D intersection is true (avoid testing the other half of a quad)
607  *  1   : occluded
608  *  2   : occluded with w[3] weights set (need to know in some cases) */
609
610 static int project_paint_occlude_ptv(float pt[3], float v1[4], float v2[4], float v3[4], float w[3], int is_ortho)
611 {
612         /* if all are behind us, return false */
613         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
614                 return 0;
615
616         /* do a 2D point in try intersection */
617         if (!isect_point_tri_v2(pt, v1, v2, v3))
618                 return 0;  /* we know there is  */
619
620
621         /* From here on we know there IS an intersection */
622         /* if ALL of the verts are infront of us then we know it intersects ? */
623         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
624                 return 1;
625         }
626         else {
627                 /* we intersect? - find the exact depth at the point of intersection */
628                 /* Is this point is occluded by another face? */
629                 if (is_ortho) {
630                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
631                 }
632                 else {
633                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
634                 }
635         }
636         return -1;
637 }
638
639
640 static int project_paint_occlude_ptv_clip(const ProjPaintState *ps, const MFace *mf,
641                                           float pt[3], float v1[4], float v2[4], float v3[4],
642                                           const int side)
643 {
644         float w[3], wco[3];
645         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, ps->is_ortho);
646
647         if (ret <= 0)
648                 return ret;
649
650         if (ret == 1) { /* weights not calculated */
651                 if (ps->is_ortho) barycentric_weights_v2(v1, v2, v3, pt, w);
652                 else barycentric_weights_v2_persp(v1, v2, v3, pt, w);
653         }
654
655         /* Test if we're in the clipped area, */
656         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);
657         else interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
658
659         if (!ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
660                 return 1;
661         }
662
663         return -1;
664 }
665
666
667 /* Check if a screenspace location is occluded by any other faces
668  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
669  * and doesn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
670 static int project_bucket_point_occluded(const ProjPaintState *ps, LinkNode *bucketFace, const int orig_face, float pixelScreenCo[4])
671 {
672         MFace *mf;
673         int face_index;
674         int isect_ret;
675         float w[3]; /* not needed when clipping */
676         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
677
678         /* we could return 0 for 1 face buckets, as long as this function assumes
679          * that the point its testing is only every originated from an existing face */
680
681         for (; bucketFace; bucketFace = bucketFace->next) {
682                 face_index = GET_INT_FROM_POINTER(bucketFace->link);
683
684                 if (orig_face != face_index) {
685                         mf = ps->dm_mface + face_index;
686                         if (do_clip)
687                                 isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], 0);
688                         else
689                                 isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], w, ps->is_ortho);
690
691                         /* Note, if (isect_ret == -1) then we don't want to test the other side of the quad */
692                         if (isect_ret == 0 && mf->v4) {
693                                 if (do_clip)
694                                         isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], 1);
695                                 else
696                                         isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], w, ps->is_ortho);
697                         }
698                         if (isect_ret >= 1) {
699                                 /* TODO - we may want to cache the first hit,
700                                  * it is not possible to swap the face order in the list anymore */
701                                 return 1;
702                         }
703                 }
704         }
705         return 0;
706 }
707
708 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
709  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
710 #define ISECT_TRUE 1
711 #define ISECT_TRUE_P1 2
712 #define ISECT_TRUE_P2 3
713 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
714 {
715         float y_diff;
716
717         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
718                 *x_isect = p1[0];
719                 return ISECT_TRUE_P1;
720         }
721         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
722                 *x_isect = p2[0];
723                 return ISECT_TRUE_P2;
724         }
725
726         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
727
728         if (y_diff < 0.000001f) {
729                 *x_isect = (p1[0] + p2[0]) * 0.5f;
730                 return ISECT_TRUE;
731         }
732
733         if (p1[1] > y_level && p2[1] < y_level) {
734                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /*(p1[1]-p2[1]);*/
735                 return ISECT_TRUE;
736         }
737         else if (p1[1] < y_level && p2[1] > y_level) {
738                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /*(p2[1]-p1[1]);*/
739                 return ISECT_TRUE;
740         }
741         else {
742                 return 0;
743         }
744 }
745
746 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
747 {
748         float x_diff;
749
750         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
751                 *y_isect = p1[1];
752                 return ISECT_TRUE_P1;
753         }
754         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
755                 *y_isect = p2[1];
756                 return ISECT_TRUE_P2;
757         }
758
759         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
760
761         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
762                 *y_isect = (p1[0] + p2[0]) * 0.5f;
763                 return ISECT_TRUE;
764         }
765
766         if (p1[0] > x_level && p2[0] < x_level) {
767                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff; /*(p1[0]-p2[0]);*/
768                 return ISECT_TRUE;
769         }
770         else if (p1[0] < x_level && p2[0] > x_level) {
771                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff; /*(p2[0]-p1[0]);*/
772                 return ISECT_TRUE;
773         }
774         else {
775                 return 0;
776         }
777 }
778
779 /* simple func use for comparing UV locations to check if there are seams.
780  * Its possible this gives incorrect results, when the UVs for 1 face go into the next
781  * tile, but do not do this for the adjacent face, it could return a false positive.
782  * This is so unlikely that Id not worry about it. */
783 #ifndef PROJ_DEBUG_NOSEAMBLEED
784 static int cmp_uv(const float vec2a[2], const float vec2b[2])
785 {
786         /* if the UV's are not between 0.0 and 1.0 */
787         float xa = (float)fmodf(vec2a[0], 1.0f);
788         float ya = (float)fmodf(vec2a[1], 1.0f);
789
790         float xb = (float)fmodf(vec2b[0], 1.0f);
791         float yb = (float)fmodf(vec2b[1], 1.0f);
792
793         if (xa < 0.0f) xa += 1.0f;
794         if (ya < 0.0f) ya += 1.0f;
795
796         if (xb < 0.0f) xb += 1.0f;
797         if (yb < 0.0f) yb += 1.0f;
798
799         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
800 }
801 #endif
802
803 /* set min_px and max_px to the image space bounds of the UV coords
804  * return zero if there is no area in the returned rectangle */
805 #ifndef PROJ_DEBUG_NOSEAMBLEED
806 static int pixel_bounds_uv(
807         const float uv1[2], const float uv2[2], const float uv3[2], const float uv4[2],
808         rcti *bounds_px,
809         const int ibuf_x, const int ibuf_y,
810         int is_quad
811         )
812 {
813         float min_uv[2], max_uv[2]; /* UV bounds */
814
815         INIT_MINMAX2(min_uv, max_uv);
816
817         minmax_v2v2_v2(min_uv, max_uv, uv1);
818         minmax_v2v2_v2(min_uv, max_uv, uv2);
819         minmax_v2v2_v2(min_uv, max_uv, uv3);
820         if (is_quad)
821                 minmax_v2v2_v2(min_uv, max_uv, uv4);
822
823         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
824         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
825
826         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
827         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
828
829         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
830
831         /* face uses no UV area when quantized to pixels? */
832         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
833 }
834 #endif
835
836 static int pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
837 {
838         float min_uv[2], max_uv[2]; /* UV bounds */
839
840         if (tot == 0) {
841                 return 0;
842         }
843
844         INIT_MINMAX2(min_uv, max_uv);
845
846         while (tot--) {
847                 minmax_v2v2_v2(min_uv, max_uv, (*uv));
848                 uv++;
849         }
850
851         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
852         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
853
854         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
855         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
856
857         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
858
859         /* face uses no UV area when quantized to pixels? */
860         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
861 }
862
863 #ifndef PROJ_DEBUG_NOSEAMBLEED
864
865 /* This function returns 1 if this face has a seam along the 2 face-vert indices
866  * 'orig_i1_fidx' and 'orig_i2_fidx' */
867 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)
868 {
869         LinkNode *node;
870         int face_index;
871         unsigned int i1, i2;
872         int i1_fidx = -1, i2_fidx = -1; /* index in face */
873         MFace *mf;
874         MTFace *tf;
875         const MFace *orig_mf = ps->dm_mface + orig_face;
876         const MTFace *orig_tf = ps->dm_mtface + orig_face;
877
878         /* vert indices from face vert order indices */
879         i1 = (*(&orig_mf->v1 + orig_i1_fidx));
880         i2 = (*(&orig_mf->v1 + orig_i2_fidx));
881
882         for (node = ps->vertFaces[i1]; node; node = node->next) {
883                 face_index = GET_INT_FROM_POINTER(node->link);
884
885                 if (face_index != orig_face) {
886                         mf = ps->dm_mface + face_index;
887                         /* could check if the 2 faces images match here,
888                          * but then there wouldn't be a way to return the opposite face's info */
889
890
891                         /* We need to know the order of the verts in the adjacent face
892                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
893                         if      (mf->v1 == i1) i1_fidx = 0;
894                         else if (mf->v2 == i1) i1_fidx = 1;
895                         else if (mf->v3 == i1) i1_fidx = 2;
896                         else if (mf->v4 && mf->v4 == i1) i1_fidx = 3;
897
898                         if      (mf->v1 == i2) i2_fidx = 0;
899                         else if (mf->v2 == i2) i2_fidx = 1;
900                         else if (mf->v3 == i2) i2_fidx = 2;
901                         else if (mf->v4 && mf->v4 == i2) i2_fidx = 3;
902
903                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
904                         if (i2_fidx != -1) {
905                                 Image *tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
906                                 Image *orig_tpage = project_paint_face_image(ps, ps->dm_mtface, orig_face);
907
908                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
909                                 tf = ps->dm_mtface + face_index;
910
911                                 /* set up the other face */
912                                 *other_face = face_index;
913                                 *orig_fidx = (i1_fidx < i2_fidx) ? i1_fidx : i2_fidx;
914
915                                 /* first test if they have the same image */
916                                 if ((orig_tpage == tpage) &&
917                                     cmp_uv(orig_tf->uv[orig_i1_fidx], tf->uv[i1_fidx]) &&
918                                     cmp_uv(orig_tf->uv[orig_i2_fidx], tf->uv[i2_fidx]) )
919                                 {
920                                         // printf("SEAM (NONE)\n");
921                                         return 0;
922
923                                 }
924                                 else {
925                                         // printf("SEAM (UV GAP)\n");
926                                         return 1;
927                                 }
928                         }
929                 }
930         }
931         // printf("SEAM (NO FACE)\n");
932         *other_face = -1;
933         return 1;
934 }
935
936 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
937  * since the outset coords are a margin that keep an even distance from the original UV's,
938  * note that the image aspect is taken into account */
939 static void uv_image_outset(float (*orig_uv)[2], float (*outset_uv)[2], const float scaler,
940                             const int ibuf_x, const int ibuf_y, const int is_quad)
941 {
942         float a1, a2, a3, a4 = 0.0f;
943         float puv[4][2]; /* pixelspace uv's */
944         float no1[2], no2[2], no3[2], no4[2]; /* normals */
945         float dir1[2], dir2[2], dir3[2], dir4[2];
946         float ibuf_inv[2];
947
948         ibuf_inv[0] = 1.0f / (float)ibuf_x;
949         ibuf_inv[1] = 1.0f / (float)ibuf_y;
950
951         /* make UV's in pixel space so we can */
952         puv[0][0] = orig_uv[0][0] * ibuf_x;
953         puv[0][1] = orig_uv[0][1] * ibuf_y;
954
955         puv[1][0] = orig_uv[1][0] * ibuf_x;
956         puv[1][1] = orig_uv[1][1] * ibuf_y;
957
958         puv[2][0] = orig_uv[2][0] * ibuf_x;
959         puv[2][1] = orig_uv[2][1] * ibuf_y;
960
961         if (is_quad) {
962                 puv[3][0] = orig_uv[3][0] * ibuf_x;
963                 puv[3][1] = orig_uv[3][1] * ibuf_y;
964         }
965
966         /* face edge directions */
967         sub_v2_v2v2(dir1, puv[1], puv[0]);
968         sub_v2_v2v2(dir2, puv[2], puv[1]);
969         normalize_v2(dir1);
970         normalize_v2(dir2);
971
972         if (is_quad) {
973                 sub_v2_v2v2(dir3, puv[3], puv[2]);
974                 sub_v2_v2v2(dir4, puv[0], puv[3]);
975                 normalize_v2(dir3);
976                 normalize_v2(dir4);
977         }
978         else {
979                 sub_v2_v2v2(dir3, puv[0], puv[2]);
980                 normalize_v2(dir3);
981         }
982
983         /* TODO - angle_normalized_v2v2(...) * (M_PI/180.0f)
984          * This is incorrect. Its already given radians but without it wont work.
985          * need to look into a fix - campbell */
986         if (is_quad) {
987                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir4, dir1) * ((float)M_PI / 180.0f));
988                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI / 180.0f));
989                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI / 180.0f));
990                 a4 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir4) * ((float)M_PI / 180.0f));
991         }
992         else {
993                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir1) * ((float)M_PI / 180.0f));
994                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI / 180.0f));
995                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI / 180.0f));
996         }
997
998         if (is_quad) {
999                 sub_v2_v2v2(no1, dir4, dir1);
1000                 sub_v2_v2v2(no2, dir1, dir2);
1001                 sub_v2_v2v2(no3, dir2, dir3);
1002                 sub_v2_v2v2(no4, dir3, dir4);
1003                 normalize_v2(no1);
1004                 normalize_v2(no2);
1005                 normalize_v2(no3);
1006                 normalize_v2(no4);
1007                 mul_v2_fl(no1, a1 * scaler);
1008                 mul_v2_fl(no2, a2 * scaler);
1009                 mul_v2_fl(no3, a3 * scaler);
1010                 mul_v2_fl(no4, a4 * scaler);
1011                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1012                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1013                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1014                 add_v2_v2v2(outset_uv[3], puv[3], no4);
1015                 mul_v2_v2(outset_uv[0], ibuf_inv);
1016                 mul_v2_v2(outset_uv[1], ibuf_inv);
1017                 mul_v2_v2(outset_uv[2], ibuf_inv);
1018                 mul_v2_v2(outset_uv[3], ibuf_inv);
1019         }
1020         else {
1021                 sub_v2_v2v2(no1, dir3, dir1);
1022                 sub_v2_v2v2(no2, dir1, dir2);
1023                 sub_v2_v2v2(no3, dir2, dir3);
1024                 normalize_v2(no1);
1025                 normalize_v2(no2);
1026                 normalize_v2(no3);
1027                 mul_v2_fl(no1, a1 * scaler);
1028                 mul_v2_fl(no2, a2 * scaler);
1029                 mul_v2_fl(no3, a3 * scaler);
1030                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1031                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1032                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1033
1034                 mul_v2_v2(outset_uv[0], ibuf_inv);
1035                 mul_v2_v2(outset_uv[1], ibuf_inv);
1036                 mul_v2_v2(outset_uv[2], ibuf_inv);
1037         }
1038 }
1039
1040 /*
1041  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1042  * 1<<i - where i is (0-3)
1043  *
1044  * If we're multithreadng, make sure threads are locked when this is called
1045  */
1046 static void project_face_seams_init(const ProjPaintState *ps, const int face_index, const int is_quad)
1047 {
1048         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1049         int fidx1 = is_quad ? 3 : 2;
1050         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 */
1051
1052         do {
1053                 if ((ps->faceSeamFlags[face_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1054                         if (check_seam(ps, face_index, fidx1, fidx2, &other_face, &other_fidx)) {
1055                                 ps->faceSeamFlags[face_index] |= 1 << fidx1;
1056                                 if (other_face != -1)
1057                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1058                         }
1059                         else {
1060                                 ps->faceSeamFlags[face_index] |= 16 << fidx1;
1061                                 if (other_face != -1)
1062                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1063                         }
1064                 }
1065
1066                 fidx2 = fidx1;
1067         } while (fidx1--);
1068 }
1069 #endif // PROJ_DEBUG_NOSEAMBLEED
1070
1071
1072 /* Converts a UV location to a 3D screenspace location
1073  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1074  *
1075  * This is used for finding a pixels location in screenspace for painting */
1076 static void screen_px_from_ortho(
1077         float uv[2],
1078         float v1co[3], float v2co[3], float v3co[3],  /* Screenspace coords */
1079         float uv1co[2], float uv2co[2], float uv3co[2],
1080         float pixelScreenCo[4],
1081         float w[3])
1082 {
1083         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1084         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1085 }
1086
1087 /* same as screen_px_from_ortho except we need to take into account
1088  * the perspective W coord for each vert */
1089 static void screen_px_from_persp(
1090         float uv[2],
1091         float v1co[4], float v2co[4], float v3co[4],  /* screenspace coords */
1092         float uv1co[2], float uv2co[2], float uv3co[2],
1093         float pixelScreenCo[4],
1094         float w[3])
1095 {
1096
1097         float wtot_inv, wtot;
1098         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1099
1100         /* re-weight from the 4th coord of each screen vert */
1101         w[0] *= v1co[3];
1102         w[1] *= v2co[3];
1103         w[2] *= v3co[3];
1104
1105         wtot = w[0] + w[1] + w[2];
1106
1107         if (wtot > 0.0f) {
1108                 wtot_inv = 1.0f / wtot;
1109                 w[0] *= wtot_inv;
1110                 w[1] *= wtot_inv;
1111                 w[2] *= wtot_inv;
1112         }
1113         else {
1114                 w[0] = w[1] = w[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1115         }
1116         /* done re-weighting */
1117
1118         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1119 }
1120
1121 static void project_face_pixel(const MTFace *tf_other, ImBuf *ibuf_other, const float w[3],
1122                                int side, unsigned char rgba_ub[4], float rgba_f[4])
1123 {
1124         float *uvCo1, *uvCo2, *uvCo3;
1125         float uv_other[2], x, y;
1126
1127         uvCo1 =  (float *)tf_other->uv[0];
1128         if (side == 1) {
1129                 uvCo2 =  (float *)tf_other->uv[2];
1130                 uvCo3 =  (float *)tf_other->uv[3];
1131         }
1132         else {
1133                 uvCo2 =  (float *)tf_other->uv[1];
1134                 uvCo3 =  (float *)tf_other->uv[2];
1135         }
1136
1137         interp_v2_v2v2v2(uv_other, uvCo1, uvCo2, uvCo3, (float *)w);
1138
1139         /* use */
1140         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1141
1142
1143         if (ibuf_other->rect_float) { /* from float to float */
1144                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1145         }
1146         else { /* from char to float */
1147                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1148         }
1149
1150 }
1151
1152 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1153 static float project_paint_uvpixel_mask(
1154         const ProjPaintState *ps,
1155         const int face_index,
1156         const int side,
1157         const float w[3])
1158 {
1159         float mask;
1160
1161         /* Image Mask */
1162         if (ps->do_layer_stencil) {
1163                 /* another UV maps image is masking this one's */
1164                 ImBuf *ibuf_other;
1165                 Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_stencil, face_index);
1166                 const MTFace *tf_other = ps->dm_mtface_stencil + face_index;
1167
1168                 if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1169                         /* BKE_image_acquire_ibuf - TODO - this may be slow */
1170                         unsigned char rgba_ub[4];
1171                         float rgba_f[4];
1172
1173                         project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, rgba_f);
1174
1175                         if (ibuf_other->rect_float) { /* from float to float */
1176                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) * (1.0f / 3.0f)) * rgba_f[3];
1177                         }
1178                         else { /* from char to float */
1179                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) * (1.0f / (255.0f * 3.0f))) * (rgba_ub[3] * (1.0f / 255.0f));
1180                         }
1181
1182                         BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1183
1184                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1185                                 mask = (1.0f - mask);
1186
1187                         if (mask == 0.0f) {
1188                                 return 0.0f;
1189                         }
1190                 }
1191                 else {
1192                         return 0.0f;
1193                 }
1194         }
1195         else {
1196                 mask = 1.0f;
1197         }
1198
1199         /* calculate mask */
1200         if (ps->do_mask_normal) {
1201                 MFace *mf = &ps->dm_mface[face_index];
1202                 float no[3], angle;
1203                 if (mf->flag & ME_SMOOTH) {
1204                         short *no1, *no2, *no3;
1205                         no1 = ps->dm_mvert[mf->v1].no;
1206                         if (side == 1) {
1207                                 no2 = ps->dm_mvert[mf->v3].no;
1208                                 no3 = ps->dm_mvert[mf->v4].no;
1209                         }
1210                         else {
1211                                 no2 = ps->dm_mvert[mf->v2].no;
1212                                 no3 = ps->dm_mvert[mf->v3].no;
1213                         }
1214
1215                         no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1216                         no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1217                         no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1218                         normalize_v3(no);
1219                 }
1220                 else {
1221                         /* incase the */
1222 #if 1
1223                         /* normalizing per pixel isn't optimal, we could cache or check ps->*/
1224                         if (mf->v4)
1225                                 normal_quad_v3(no,
1226                                                ps->dm_mvert[mf->v1].co,
1227                                                ps->dm_mvert[mf->v2].co,
1228                                                ps->dm_mvert[mf->v3].co,
1229                                                ps->dm_mvert[mf->v4].co);
1230                         else
1231                                 normal_tri_v3(no,
1232                                               ps->dm_mvert[mf->v1].co,
1233                                               ps->dm_mvert[mf->v2].co,
1234                                               ps->dm_mvert[mf->v3].co);
1235 #else
1236                         /* don't use because some modifiers dont have normal data (subsurf for eg) */
1237                         copy_v3_v3(no, (float *)ps->dm->getTessFaceData(ps->dm, face_index, CD_NORMAL));
1238 #endif
1239                 }
1240
1241                 /* now we can use the normal as a mask */
1242                 if (ps->is_ortho) {
1243                         angle = angle_normalized_v3v3((float *)ps->viewDir, no);
1244                 }
1245                 else {
1246                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1247                         float viewDirPersp[3];
1248                         float *co1, *co2, *co3;
1249                         co1 = ps->dm_mvert[mf->v1].co;
1250                         if (side == 1) {
1251                                 co2 = ps->dm_mvert[mf->v3].co;
1252                                 co3 = ps->dm_mvert[mf->v4].co;
1253                         }
1254                         else {
1255                                 co2 = ps->dm_mvert[mf->v2].co;
1256                                 co3 = ps->dm_mvert[mf->v3].co;
1257                         }
1258
1259                         /* Get the direction from the viewPoint to the pixel and normalize */
1260                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1261                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1262                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1263                         normalize_v3(viewDirPersp);
1264
1265                         angle = angle_normalized_v3v3(viewDirPersp, no);
1266                 }
1267
1268                 if (angle >= ps->normal_angle) {
1269                         return 0.0f; /* outsize the normal limit*/
1270                 }
1271                 else if (angle > ps->normal_angle_inner) {
1272                         mask *= (ps->normal_angle - angle) / ps->normal_angle_range;
1273                 } /* otherwise no mask normal is needed, were within the limit */
1274         }
1275
1276         /* This only works when the opacity dosnt change while painting, stylus pressure messes with this
1277          * so don't use it. */
1278         // if (ps->is_airbrush == 0) mask *= BKE_brush_alpha_get(ps->brush);
1279
1280         return mask;
1281 }
1282
1283 static int project_paint_pixel_sizeof(const short tool)
1284 {
1285         if ((tool == PAINT_TOOL_CLONE) || (tool == PAINT_TOOL_SMEAR)) {
1286                 return sizeof(ProjPixelClone);
1287         }
1288         else {
1289                 return sizeof(ProjPixel);
1290         }
1291 }
1292
1293
1294 /* run this function when we know a bucket's, face's pixel can be initialized,
1295  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1296 static ProjPixel *project_paint_uvpixel_init(
1297         const ProjPaintState *ps,
1298         MemArena *arena,
1299         const ImBuf *ibuf,
1300         short x_px, short y_px,
1301         const float mask,
1302         const int face_index,
1303         const int image_index,
1304         const float pixelScreenCo[4],
1305         const float world_spaceCo[3],
1306         const int side,
1307         const float w[3])
1308 {
1309         ProjPixel *projPixel;
1310
1311         /* wrap pixel location */
1312         x_px = x_px % ibuf->x;
1313         if (x_px < 0) x_px += ibuf->x;
1314         y_px = y_px % ibuf->y;
1315         if (y_px < 0) y_px += ibuf->y;
1316
1317         BLI_assert(ps->pixel_sizeof == project_paint_pixel_sizeof(ps->tool));
1318         projPixel = (ProjPixel *)BLI_memarena_alloc(arena, ps->pixel_sizeof);
1319         //memset(projPixel, 0, size);
1320
1321         if (ibuf->rect_float) {
1322                 projPixel->pixel.f_pt = ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1323                 projPixel->origColor.f[0] = projPixel->pixel.f_pt[0];
1324                 projPixel->origColor.f[1] = projPixel->pixel.f_pt[1];
1325                 projPixel->origColor.f[2] = projPixel->pixel.f_pt[2];
1326                 projPixel->origColor.f[3] = projPixel->pixel.f_pt[3];
1327                 zero_v4(projPixel->newColor.f);
1328         }
1329         else {
1330                 projPixel->pixel.ch_pt = ((unsigned char *)ibuf->rect + ((x_px + y_px * ibuf->x) * 4));
1331                 projPixel->origColor.uint = *projPixel->pixel.uint_pt;
1332                 projPixel->newColor.uint = 0;
1333         }
1334
1335         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1336         if (ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D) {
1337                 copy_v3_v3(projPixel->worldCoSS, world_spaceCo);
1338         }
1339
1340         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1341
1342         projPixel->x_px = x_px;
1343         projPixel->y_px = y_px;
1344
1345         projPixel->mask = (unsigned short)(mask * 65535);
1346         projPixel->mask_accum = 0;
1347
1348         /* which bounding box cell are we in?, needed for undo */
1349         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1350                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1351
1352         /* done with view3d_project_float inline */
1353         if (ps->tool == PAINT_TOOL_CLONE) {
1354                 if (ps->dm_mtface_clone) {
1355                         ImBuf *ibuf_other;
1356                         Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_clone, face_index);
1357                         const MTFace *tf_other = ps->dm_mtface_clone + face_index;
1358
1359                         if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1360                                 /* BKE_image_acquire_ibuf - TODO - this may be slow */
1361
1362                                 if (ibuf->rect_float) {
1363                                         if (ibuf_other->rect_float) { /* from float to float */
1364                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1365                                         }
1366                                         else { /* from char to float */
1367                                                 unsigned char rgba_ub[4];
1368                                                 float rgba[4];
1369                                                 project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, NULL);
1370                                                 srgb_to_linearrgb_uchar4(rgba, rgba_ub);
1371                                                 straight_to_premul_v4_v4(((ProjPixelClone *)projPixel)->clonepx.f, rgba);
1372                                         }
1373                                 }
1374                                 else {
1375                                         if (ibuf_other->rect_float) { /* float to char */
1376                                                 float rgba[4];
1377                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, rgba);
1378                                                 premul_to_straight_v4(rgba);
1379                                                 linearrgb_to_srgb_uchar3(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1380                                         }
1381                                         else { /* char to char */
1382                                                 project_face_pixel(tf_other, ibuf_other, w, side, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1383                                         }
1384                                 }
1385
1386                                 BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1387                         }
1388                         else {
1389                                 if (ibuf->rect_float) {
1390                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1391                                 }
1392                                 else {
1393                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1394                                 }
1395                         }
1396
1397                 }
1398                 else {
1399                         float co[2];
1400                         sub_v2_v2v2(co, projPixel->projCoSS, (float *)ps->cloneOffset);
1401
1402                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1403                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1404                         if (ibuf->rect_float) {
1405                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1406                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1407                                 }
1408                         }
1409                         else {
1410                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1411                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1412                                 }
1413                         }
1414                 }
1415         }
1416
1417 #ifdef PROJ_DEBUG_PAINT
1418         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1419         else                  projPixel->pixel.ch_pt[0] = 0;
1420 #endif
1421         projPixel->image_index = image_index;
1422
1423         return projPixel;
1424 }
1425
1426 static int line_clip_rect2f(
1427         rctf *rect,
1428         const float l1[2], const float l2[2],
1429         float l1_clip[2], float l2_clip[2])
1430 {
1431         /* first account for horizontal, then vertical lines */
1432         /* horiz */
1433         if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) {
1434                 /* is the line out of range on its Y axis? */
1435                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1436                         return 0;
1437                 }
1438                 /* line is out of range on its X axis */
1439                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1440                         return 0;
1441                 }
1442
1443
1444                 if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1445                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1446                                 copy_v2_v2(l1_clip, l1);
1447                                 copy_v2_v2(l2_clip, l2);
1448                                 return 1;
1449                         }
1450                         else {
1451                                 return 0;
1452                         }
1453                 }
1454
1455                 copy_v2_v2(l1_clip, l1);
1456                 copy_v2_v2(l2_clip, l2);
1457                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1458                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1459                 return 1;
1460         }
1461         else if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) {
1462                 /* is the line out of range on its X axis? */
1463                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1464                         return 0;
1465                 }
1466
1467                 /* line is out of range on its Y axis */
1468                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1469                         return 0;
1470                 }
1471
1472                 if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1473                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1474                                 copy_v2_v2(l1_clip, l1);
1475                                 copy_v2_v2(l2_clip, l2);
1476                                 return 1;
1477                         }
1478                         else {
1479                                 return 0;
1480                         }
1481                 }
1482
1483                 copy_v2_v2(l1_clip, l1);
1484                 copy_v2_v2(l2_clip, l2);
1485                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1486                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1487                 return 1;
1488         }
1489         else {
1490                 float isect;
1491                 short ok1 = 0;
1492                 short ok2 = 0;
1493
1494                 /* Done with vertical lines */
1495
1496                 /* are either of the points inside the rectangle ? */
1497                 if (BLI_rctf_isect_pt_v(rect, l1)) {
1498                         copy_v2_v2(l1_clip, l1);
1499                         ok1 = 1;
1500                 }
1501
1502                 if (BLI_rctf_isect_pt_v(rect, l2)) {
1503                         copy_v2_v2(l2_clip, l2);
1504                         ok2 = 1;
1505                 }
1506
1507                 /* line inside rect */
1508                 if (ok1 && ok2) return 1;
1509
1510                 /* top/bottom */
1511                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1512                         if (l1[1] < l2[1]) { /* line 1 is outside */
1513                                 l1_clip[0] = isect;
1514                                 l1_clip[1] = rect->ymin;
1515                                 ok1 = 1;
1516                         }
1517                         else {
1518                                 l2_clip[0] = isect;
1519                                 l2_clip[1] = rect->ymin;
1520                                 ok2 = 2;
1521                         }
1522                 }
1523
1524                 if (ok1 && ok2) return 1;
1525
1526                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1527                         if (l1[1] > l2[1]) { /* line 1 is outside */
1528                                 l1_clip[0] = isect;
1529                                 l1_clip[1] = rect->ymax;
1530                                 ok1 = 1;
1531                         }
1532                         else {
1533                                 l2_clip[0] = isect;
1534                                 l2_clip[1] = rect->ymax;
1535                                 ok2 = 2;
1536                         }
1537                 }
1538
1539                 if (ok1 && ok2) return 1;
1540
1541                 /* left/right */
1542                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1543                         if (l1[0] < l2[0]) { /* line 1 is outside */
1544                                 l1_clip[0] = rect->xmin;
1545                                 l1_clip[1] = isect;
1546                                 ok1 = 1;
1547                         }
1548                         else {
1549                                 l2_clip[0] = rect->xmin;
1550                                 l2_clip[1] = isect;
1551                                 ok2 = 2;
1552                         }
1553                 }
1554
1555                 if (ok1 && ok2) return 1;
1556
1557                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1558                         if (l1[0] > l2[0]) { /* line 1 is outside */
1559                                 l1_clip[0] = rect->xmax;
1560                                 l1_clip[1] = isect;
1561                                 ok1 = 1;
1562                         }
1563                         else {
1564                                 l2_clip[0] = rect->xmax;
1565                                 l2_clip[1] = isect;
1566                                 ok2 = 2;
1567                         }
1568                 }
1569
1570                 if (ok1 && ok2) {
1571                         return 1;
1572                 }
1573                 else {
1574                         return 0;
1575                 }
1576         }
1577 }
1578
1579
1580
1581 /* scale the quad & tri about its center
1582  * scaling by PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1583  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces */
1584 #ifndef PROJ_DEBUG_NOSEAMBLEED
1585 static void scale_quad(float insetCos[4][3], float *origCos[4], const float inset)
1586 {
1587         float cent[3];
1588         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0] + origCos[3][0]) * (1.0f / 4.0f);
1589         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1] + origCos[3][1]) * (1.0f / 4.0f);
1590         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2] + origCos[3][2]) * (1.0f / 4.0f);
1591
1592         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1593         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1594         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1595         sub_v3_v3v3(insetCos[3], origCos[3], cent);
1596
1597         mul_v3_fl(insetCos[0], inset);
1598         mul_v3_fl(insetCos[1], inset);
1599         mul_v3_fl(insetCos[2], inset);
1600         mul_v3_fl(insetCos[3], inset);
1601
1602         add_v3_v3(insetCos[0], cent);
1603         add_v3_v3(insetCos[1], cent);
1604         add_v3_v3(insetCos[2], cent);
1605         add_v3_v3(insetCos[3], cent);
1606 }
1607
1608
1609 static void scale_tri(float insetCos[4][3], float *origCos[4], const float inset)
1610 {
1611         float cent[3];
1612         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) * (1.0f / 3.0f);
1613         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) * (1.0f / 3.0f);
1614         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) * (1.0f / 3.0f);
1615
1616         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1617         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1618         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1619
1620         mul_v3_fl(insetCos[0], inset);
1621         mul_v3_fl(insetCos[1], inset);
1622         mul_v3_fl(insetCos[2], inset);
1623
1624         add_v3_v3(insetCos[0], cent);
1625         add_v3_v3(insetCos[1], cent);
1626         add_v3_v3(insetCos[2], cent);
1627 }
1628 #endif //PROJ_DEBUG_NOSEAMBLEED
1629
1630 static float len_squared_v2v2_alt(const float *v1, const float v2_1, const float v2_2)
1631 {
1632         float x, y;
1633
1634         x = v1[0] - v2_1;
1635         y = v1[1] - v2_2;
1636         return x * x + y * y;
1637 }
1638
1639 /* note, use a squared value so we can use len_squared_v2v2
1640  * be sure that you have done a bounds check first or this may fail */
1641 /* only give bucket_bounds as an arg because we need it elsewhere */
1642 static int project_bucket_isect_circle(const float cent[2], const float radius_squared, rctf *bucket_bounds)
1643 {
1644
1645         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect
1646          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1647          * this is even less work then an intersection test
1648          */
1649 #if 0
1650         if (BLI_rctf_isect_pt_v(bucket_bounds, cent))
1651                 return 1;
1652 #endif
1653
1654         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1655             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1656         {
1657                 return 1;
1658         }
1659
1660         /* out of bounds left */
1661         if (cent[0] < bucket_bounds->xmin) {
1662                 /* lower left out of radius test */
1663                 if (cent[1] < bucket_bounds->ymin) {
1664                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1665                 }
1666                 /* top left test */
1667                 else if (cent[1] > bucket_bounds->ymax) {
1668                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1669                 }
1670         }
1671         else if (cent[0] > bucket_bounds->xmax) {
1672                 /* lower right out of radius test */
1673                 if (cent[1] < bucket_bounds->ymin) {
1674                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1675                 }
1676                 /* top right test */
1677                 else if (cent[1] > bucket_bounds->ymax) {
1678                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1679                 }
1680         }
1681
1682         return 0;
1683 }
1684
1685
1686
1687 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1688  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1689  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1690  * (viewed from the side)
1691  *
1692  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1693  * funcs that only account for points inside the triangle.
1694  * however switching back to this for ortho is always an option */
1695
1696 static void rect_to_uvspace_ortho(
1697         rctf *bucket_bounds,
1698         float *v1coSS, float *v2coSS, float *v3coSS,
1699         float *uv1co, float *uv2co, float *uv3co,
1700         float bucket_bounds_uv[4][2],
1701         const int flip)
1702 {
1703         float uv[2];
1704         float w[3];
1705
1706         /* get the UV space bounding box */
1707         uv[0] = bucket_bounds->xmax;
1708         uv[1] = bucket_bounds->ymin;
1709         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1710         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1711
1712         //uv[0] = bucket_bounds->xmax; // set above
1713         uv[1] = bucket_bounds->ymax;
1714         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1715         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1716
1717         uv[0] = bucket_bounds->xmin;
1718         //uv[1] = bucket_bounds->ymax; // set above
1719         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1720         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1721
1722         //uv[0] = bucket_bounds->xmin; // set above
1723         uv[1] = bucket_bounds->ymin;
1724         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1725         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1726 }
1727
1728 /* same as above but use barycentric_weights_v2_persp */
1729 static void rect_to_uvspace_persp(
1730         rctf *bucket_bounds,
1731         float *v1coSS, float *v2coSS, float *v3coSS,
1732         float *uv1co, float *uv2co, float *uv3co,
1733         float bucket_bounds_uv[4][2],
1734         const int flip
1735         )
1736 {
1737         float uv[2];
1738         float w[3];
1739
1740         /* get the UV space bounding box */
1741         uv[0] = bucket_bounds->xmax;
1742         uv[1] = bucket_bounds->ymin;
1743         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1744         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1745
1746         //uv[0] = bucket_bounds->xmax; // set above
1747         uv[1] = bucket_bounds->ymax;
1748         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1749         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1750
1751         uv[0] = bucket_bounds->xmin;
1752         //uv[1] = bucket_bounds->ymax; // set above
1753         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1754         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1755
1756         //uv[0] = bucket_bounds->xmin; // set above
1757         uv[1] = bucket_bounds->ymin;
1758         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1759         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1760 }
1761
1762 /* This works as we need it to but we can save a few steps and not use it */
1763
1764 #if 0
1765 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
1766 {
1767         float v1[2], v2[2];
1768
1769         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
1770         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
1771
1772         return -atan2(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
1773 }
1774 #endif
1775
1776 #define ISECT_1 (1)
1777 #define ISECT_2 (1 << 1)
1778 #define ISECT_3 (1 << 2)
1779 #define ISECT_4 (1 << 3)
1780 #define ISECT_ALL3 ((1 << 3) - 1)
1781 #define ISECT_ALL4 ((1 << 4) - 1)
1782
1783 /* limit must be a fraction over 1.0f */
1784 static int IsectPT2Df_limit(float pt[2], float v1[2], float v2[2], float v3[2], float limit)
1785 {
1786         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;
1787 }
1788
1789 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
1790  * so we have the clipped UV's to do pixel intersection tests with
1791  * */
1792 static int float_z_sort_flip(const void *p1, const void *p2)
1793 {
1794         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
1795 }
1796
1797 static int float_z_sort(const void *p1, const void *p2)
1798 {
1799         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
1800 }
1801
1802 static void project_bucket_clip_face(
1803         const int is_ortho,
1804         rctf *bucket_bounds,
1805         float *v1coSS, float *v2coSS, float *v3coSS,
1806         float *uv1co, float *uv2co, float *uv3co,
1807         float bucket_bounds_uv[8][2],
1808         int *tot)
1809 {
1810         int inside_bucket_flag = 0;
1811         int inside_face_flag = 0;
1812         const int flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
1813
1814         float bucket_bounds_ss[4][2];
1815
1816         /* get the UV space bounding box */
1817         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v1coSS);
1818         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v2coSS) << 1;
1819         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v3coSS) << 2;
1820
1821         if (inside_bucket_flag == ISECT_ALL3) {
1822                 /* all screenspace points are inside the bucket bounding box, this means we don't need to clip and can simply return the UVs */
1823                 if (flip) { /* facing the back? */
1824                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
1825                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1826                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
1827                 }
1828                 else {
1829                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
1830                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1831                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
1832                 }
1833
1834                 *tot = 3;
1835                 return;
1836         }
1837
1838         /* get the UV space bounding box */
1839         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
1840         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
1841         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
1842         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
1843
1844         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
1845         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
1846         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
1847
1848         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
1849         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
1850         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
1851
1852         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
1853         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
1854         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
1855
1856         if (inside_face_flag == ISECT_ALL4) {
1857                 /* bucket is totally inside the screenspace face, we can safely use weights */
1858
1859                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
1860                 else rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
1861
1862                 *tot = 4;
1863                 return;
1864         }
1865         else {
1866                 /* The Complicated Case!
1867                  *
1868                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
1869                  *
1870                  * we need to make a convex polyline from the intersection between the screenspace face
1871                  * and the bucket bounds.
1872                  *
1873                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
1874                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
1875                  * do a correct clipping on both shapes. */
1876
1877
1878                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
1879
1880
1881
1882                 /* Maximum possible 6 intersections when using a rectangle and triangle */
1883                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
1884                 float v1_clipSS[2], v2_clipSS[2];
1885                 float w[3];
1886
1887                 /* calc center */
1888                 float cent[2] = {0.0f, 0.0f};
1889                 /*float up[2] = {0.0f, 1.0f};*/
1890                 int i;
1891                 short doubles;
1892
1893                 (*tot) = 0;
1894
1895                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
1896                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
1897                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
1898                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
1899
1900                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
1901                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
1902                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
1903
1904                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
1905                         if (line_clip_rect2f(bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
1906                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
1907                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
1908                         }
1909                 }
1910
1911                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
1912                         if (line_clip_rect2f(bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
1913                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
1914                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
1915                         }
1916                 }
1917
1918                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
1919                         if (line_clip_rect2f(bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
1920                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
1921                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
1922                         }
1923                 }
1924
1925
1926                 if ((*tot) < 3) { /* no intersections to speak of */
1927                         *tot = 0;
1928                         return;
1929                 }
1930
1931                 /* now we have all points we need, collect their angles and sort them clockwise */
1932
1933                 for (i = 0; i < (*tot); i++) {
1934                         cent[0] += isectVCosSS[i][0];
1935                         cent[1] += isectVCosSS[i][1];
1936                 }
1937                 cent[0] = cent[0] / (float)(*tot);
1938                 cent[1] = cent[1] / (float)(*tot);
1939
1940
1941
1942                 /* Collect angles for every point around the center point */
1943
1944
1945 #if 0   /* uses a few more cycles then the above loop */
1946                 for (i = 0; i < (*tot); i++) {
1947                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
1948                 }
1949 #endif
1950
1951                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
1952                 v1_clipSS[1] = cent[1] + 1.0f;
1953
1954                 for (i = 0; i < (*tot); i++) {
1955                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
1956                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
1957                         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]);
1958                 }
1959
1960                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
1961                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
1962
1963                 /* remove doubles */
1964                 /* first/last check */
1965                 if (fabsf(isectVCosSS[0][0] - isectVCosSS[(*tot) - 1][0]) < PROJ_GEOM_TOLERANCE &&
1966                     fabsf(isectVCosSS[0][1] - isectVCosSS[(*tot) - 1][1]) < PROJ_GEOM_TOLERANCE)
1967                 {
1968                         (*tot)--;
1969                 }
1970
1971                 /* its possible there is only a few left after remove doubles */
1972                 if ((*tot) < 3) {
1973                         // printf("removed too many doubles A\n");
1974                         *tot = 0;
1975                         return;
1976                 }
1977
1978                 doubles = TRUE;
1979                 while (doubles == TRUE) {
1980                         doubles = FALSE;
1981                         for (i = 1; i < (*tot); i++) {
1982                                 if (fabsf(isectVCosSS[i - 1][0] - isectVCosSS[i][0]) < PROJ_GEOM_TOLERANCE &&
1983                                     fabsf(isectVCosSS[i - 1][1] - isectVCosSS[i][1]) < PROJ_GEOM_TOLERANCE)
1984                                 {
1985                                         int j;
1986                                         for (j = i + 1; j < (*tot); j++) {
1987                                                 isectVCosSS[j - 1][0] = isectVCosSS[j][0];
1988                                                 isectVCosSS[j - 1][1] = isectVCosSS[j][1];
1989                                         }
1990                                         doubles = TRUE; /* keep looking for more doubles */
1991                                         (*tot)--;
1992                                 }
1993                         }
1994                 }
1995
1996                 /* its possible there is only a few left after remove doubles */
1997                 if ((*tot) < 3) {
1998                         // printf("removed too many doubles B\n");
1999                         *tot = 0;
2000                         return;
2001                 }
2002
2003
2004                 if (is_ortho) {
2005                         for (i = 0; i < (*tot); i++) {
2006                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2007                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2008                         }
2009                 }
2010                 else {
2011                         for (i = 0; i < (*tot); i++) {
2012                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2013                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2014                         }
2015                 }
2016         }
2017
2018 #ifdef PROJ_DEBUG_PRINT_CLIP
2019         /* include this at the bottom of the above function to debug the output */
2020
2021         {
2022                 /* If there are ever any problems, */
2023                 float test_uv[4][2];
2024                 int i;
2025                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2026                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2027                 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]);
2028
2029                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2030
2031                 printf("[");
2032                 for (i = 0; i < (*tot); i++) {
2033                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2034                 }
2035                 printf("]),\\\n");
2036         }
2037 #endif
2038 }
2039
2040 /*
2041  * # This script creates faces in a blender scene from printed data above.
2042  *
2043  * project_ls = [
2044  * ...(output from above block)...
2045  * ]
2046  *
2047  * from Blender import Scene, Mesh, Window, sys, Mathutils
2048  *
2049  * import bpy
2050  *
2051  * V = Mathutils.Vector
2052  *
2053  * def main():
2054  *     sce = bpy.data.scenes.active
2055  *
2056  *     for item in project_ls:
2057  *         bb = item[0]
2058  *         uv = item[1]
2059  *         poly = item[2]
2060  *
2061  *         me = bpy.data.meshes.new()
2062  *         ob = sce.objects.new(me)
2063  *
2064  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2065  *         me.faces.extend([(0,1,2,3),])
2066  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2067  *         me.faces.extend([(4,5,6),])
2068  *
2069  *         vs = [V(p).xyz for p in poly]
2070  *         print len(vs)
2071  *         l = len(me.verts)
2072  *         me.verts.extend(vs)
2073  *
2074  *         i = l
2075  *         while i < len(me.verts):
2076  *             ii = i + 1
2077  *             if ii == len(me.verts):
2078  *                 ii = l
2079  *             me.edges.extend([i, ii])
2080  *             i += 1
2081  *
2082  * if __name__ == '__main__':
2083  *     main()
2084  */
2085
2086
2087 #undef ISECT_1
2088 #undef ISECT_2
2089 #undef ISECT_3
2090 #undef ISECT_4
2091 #undef ISECT_ALL3
2092 #undef ISECT_ALL4
2093
2094
2095 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2096  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2097 static int IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2098 {
2099         int i;
2100         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2101                 return 0;
2102
2103         for (i = 1; i < tot; i++) {
2104                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2105                         return 0;
2106
2107         }
2108
2109         return 1;
2110 }
2111 static int IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2112 {
2113         int i;
2114         int side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2115
2116         for (i = 1; i < tot; i++) {
2117                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2118                         return 0;
2119
2120         }
2121
2122         return 1;
2123 }
2124
2125 /* One of the most important function for projection painting, since it selects the pixels to be added into each bucket.
2126  * initialize pixels from this face where it intersects with the bucket_index, optionally initialize pixels for removing seams */
2127 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)
2128 {
2129         /* Projection vars, to get the 3D locations into screen space  */
2130         MemArena *arena = ps->arena_mt[thread_index];
2131         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2132         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2133
2134         const MFace *mf = ps->dm_mface + face_index;
2135         const MTFace *tf = ps->dm_mtface + face_index;
2136
2137         /* UV/pixel seeking data */
2138         int x; /* Image X-Pixel */
2139         int y; /* Image Y-Pixel */
2140         float mask;
2141         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2142
2143         int side;
2144         float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to mf->v1,2,3 or mf->v1,3,4 */
2145
2146         float *vCo[4]; /* vertex screenspace coords */
2147
2148         float w[3], wco[3];
2149
2150         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to tf->uv[0],1,2 or tf->uv[0],2,3 */
2151         float pixelScreenCo[4];
2152         bool do_3d_mapping = ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D;
2153
2154         rcti bounds_px; /* ispace bounds */
2155         /* vars for getting uvspace bounds */
2156
2157         float tf_uv_pxoffset[4][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2158         float xhalfpx, yhalfpx;
2159         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2160
2161         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2162
2163         int i1, i2, i3;
2164
2165         float uv_clip[8][2];
2166         int uv_clip_tot;
2167         const short is_ortho = ps->is_ortho;
2168         const short do_backfacecull = ps->do_backfacecull;
2169         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2170
2171         vCo[0] = ps->dm_mvert[mf->v1].co;
2172         vCo[1] = ps->dm_mvert[mf->v2].co;
2173         vCo[2] = ps->dm_mvert[mf->v3].co;
2174
2175
2176         /* Use tf_uv_pxoffset instead of tf->uv so we can offset the UV half a pixel
2177          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2178          * problems when wrapping negative coords */
2179         xhalfpx = (0.5f + (PROJ_GEOM_TOLERANCE * (1.0f / 3.0f))) / ibuf_xf;
2180         yhalfpx = (0.5f + (PROJ_GEOM_TOLERANCE * (1.0f / 4.0f))) / ibuf_yf;
2181
2182         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2183          * Needed to add this offset since UV coords are often quads aligned to pixels.
2184          * In this case pixels can be exactly between 2 triangles causing nasty
2185          * artifacts.
2186          *
2187          * This workaround can be removed and painting will still work on most cases
2188          * but since the first thing most people try is painting onto a quad- better make it work.
2189          */
2190
2191
2192
2193         tf_uv_pxoffset[0][0] = tf->uv[0][0] - xhalfpx;
2194         tf_uv_pxoffset[0][1] = tf->uv[0][1] - yhalfpx;
2195
2196         tf_uv_pxoffset[1][0] = tf->uv[1][0] - xhalfpx;
2197         tf_uv_pxoffset[1][1] = tf->uv[1][1] - yhalfpx;
2198
2199         tf_uv_pxoffset[2][0] = tf->uv[2][0] - xhalfpx;
2200         tf_uv_pxoffset[2][1] = tf->uv[2][1] - yhalfpx;
2201
2202         if (mf->v4) {
2203                 vCo[3] = ps->dm_mvert[mf->v4].co;
2204
2205                 tf_uv_pxoffset[3][0] = tf->uv[3][0] - xhalfpx;
2206                 tf_uv_pxoffset[3][1] = tf->uv[3][1] - yhalfpx;
2207                 side = 1;
2208         }
2209         else {
2210                 side = 0;
2211         }
2212
2213         do {
2214                 if (side == 1) {
2215                         i1 = 0; i2 = 2; i3 = 3;
2216                 }
2217                 else {
2218                         i1 = 0; i2 = 1; i3 = 2;
2219                 }
2220
2221                 uv1co = tf_uv_pxoffset[i1]; // was tf->uv[i1];
2222                 uv2co = tf_uv_pxoffset[i2]; // was tf->uv[i2];
2223                 uv3co = tf_uv_pxoffset[i3]; // was tf->uv[i3];
2224
2225                 v1coSS = ps->screenCoords[(*(&mf->v1 + i1))];
2226                 v2coSS = ps->screenCoords[(*(&mf->v1 + i2))];
2227                 v3coSS = ps->screenCoords[(*(&mf->v1 + i3))];
2228
2229                 /* This funtion gives is a concave polyline in UV space from the clipped quad and tri*/
2230                 project_bucket_clip_face(
2231                         is_ortho, bucket_bounds,
2232                         v1coSS, v2coSS, v3coSS,
2233                         uv1co, uv2co, uv3co,
2234                         uv_clip, &uv_clip_tot
2235                         );
2236
2237                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2238 #if 0
2239                 if (uv_clip_tot > 6) {
2240                         printf("this should never happen! %d\n", uv_clip_tot);
2241                 }
2242 #endif
2243
2244                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2245
2246                         if (clamp_u) {
2247                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2248                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2249                         }
2250
2251                         if (clamp_v) {
2252                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2253                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2254                         }
2255
2256                         /* clip face and */
2257
2258                         has_isect = 0;
2259                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2260                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2261                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2262
2263                                 has_x_isect = 0;
2264                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2265                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2266                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2267
2268                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2269                                          * could check the poly direction but better to do this */
2270                                         if ((do_backfacecull == TRUE  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2271                                             (do_backfacecull == FALSE && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2272                                         {
2273
2274                                                 has_x_isect = has_isect = 1;
2275
2276                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2277                                                 else          screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2278
2279                                                 /* a pity we need to get the worldspace pixel location here */
2280                                                 if (do_clip || do_3d_mapping) {
2281                                                         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);
2282                                                         if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2283                                                                 continue; /* Watch out that no code below this needs to run */
2284                                                         }
2285                                                 }
2286
2287                                                 /* Is this UV visible from the view? - raytrace */
2288                                                 /* project_paint_PickFace is less complex, use for testing */
2289                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == face_index) {
2290                                                 if ((ps->do_occlude == FALSE) ||
2291                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2292                                                 {
2293                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2294
2295                                                         if (mask > 0.0f) {
2296                                                                 BLI_linklist_prepend_arena(
2297                                                                         bucketPixelNodes,
2298                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index,
2299                                                                                                    image_index, pixelScreenCo, wco, side, w),
2300                                                                         arena
2301                                                                         );
2302                                                         }
2303                                                 }
2304
2305                                         }
2306 //#if 0
2307                                         else if (has_x_isect) {
2308                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2309                                                 break;
2310                                         }
2311 //#endif
2312                                 }
2313
2314
2315 #if 0           /* TODO - investigate why this dosnt work sometimes! it should! */
2316                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2317                                 if (has_x_isect == 0 && has_isect) {
2318                                         break;
2319                                 }
2320 #endif
2321                         }
2322                 }
2323         } while (side--);
2324
2325
2326
2327 #ifndef PROJ_DEBUG_NOSEAMBLEED
2328         if (ps->seam_bleed_px > 0.0f) {
2329                 int face_seam_flag;
2330
2331                 if (ps->thread_tot > 1)
2332                         BLI_lock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2333
2334                 face_seam_flag = ps->faceSeamFlags[face_index];
2335
2336                 /* are any of our edges un-initialized? */
2337                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_NOSEAM1)) == 0 ||
2338                     (face_seam_flag & (PROJ_FACE_SEAM2 | PROJ_FACE_NOSEAM2)) == 0 ||
2339                     (face_seam_flag & (PROJ_FACE_SEAM3 | PROJ_FACE_NOSEAM3)) == 0 ||
2340                     (face_seam_flag & (PROJ_FACE_SEAM4 | PROJ_FACE_NOSEAM4)) == 0)
2341                 {
2342                         project_face_seams_init(ps, face_index, mf->v4);
2343                         face_seam_flag = ps->faceSeamFlags[face_index];
2344                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3, flag&PROJ_FACE_SEAM4);
2345                 }
2346
2347                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_SEAM2 | PROJ_FACE_SEAM3 | PROJ_FACE_SEAM4)) == 0) {
2348
2349                         if (ps->thread_tot > 1)
2350                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2351
2352                 }
2353                 else {
2354                         /* we have a seam - deal with it! */
2355
2356                         /* Now create new UV's for the seam face */
2357                         float (*outset_uv)[2] = ps->faceSeamUVs[face_index];
2358                         float insetCos[4][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2359
2360                         float *vCoSS[4]; /* vertex screenspace coords */
2361
2362                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2363                         float edge_verts_inset_clip[2][3];
2364                         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 */
2365
2366                         float seam_subsection[4][2];
2367                         float fac1, fac2, ftot;
2368
2369
2370                         if (outset_uv[0][0] == FLT_MAX) /* first time initialize */
2371                                 uv_image_outset(tf_uv_pxoffset, outset_uv, ps->seam_bleed_px, ibuf->x, ibuf->y, mf->v4);
2372
2373                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2374                         if (ps->thread_tot > 1)
2375                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2376
2377                         vCoSS[0] = ps->screenCoords[mf->v1];
2378                         vCoSS[1] = ps->screenCoords[mf->v2];
2379                         vCoSS[2] = ps->screenCoords[mf->v3];
2380                         if (mf->v4)
2381                                 vCoSS[3] = ps->screenCoords[mf->v4];
2382
2383                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2384                         if (is_ortho) {
2385                                 if (mf->v4) scale_quad(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2386                                 else        scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2387                         }
2388                         else {
2389                                 if (mf->v4) scale_quad(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2390                                 else        scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2391                         }
2392
2393                         side = 0; /* for triangles this wont need to change */
2394
2395                         for (fidx1 = 0; fidx1 < (mf->v4 ? 4 : 3); fidx1++) {
2396                                 if (mf->v4) fidx2 = (fidx1 == 3) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2,3) -> (1,2,3,0) */
2397                                 else        fidx2 = (fidx1 == 2) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2) -> (1,2,0) */
2398
2399                                 if ((face_seam_flag & (1 << fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2400                                     line_clip_rect2f(bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1]))
2401                                 {
2402
2403                                         ftot = len_v2v2(vCoSS[fidx1], vCoSS[fidx2]); /* screenspace edge length */
2404
2405                                         if (ftot > 0.0f) { /* avoid div by zero */
2406                                                 if (mf->v4) {
2407                                                         if (fidx1 == 2 || fidx2 == 2) side = 1;
2408                                                         else side = 0;
2409                                                 }
2410
2411                                                 fac1 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[0]) / ftot;
2412                                                 fac2 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[1]) / ftot;
2413
2414                                                 interp_v2_v2v2(seam_subsection[0], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac1);
2415                                                 interp_v2_v2v2(seam_subsection[1], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac2);
2416
2417                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2418                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2419
2420                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2421                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2422                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2423                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2424
2425
2426                                                 if (pixel_bounds_uv(seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3], &bounds_px, ibuf->x, ibuf->y, 1)) {
2427                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2428
2429                                                         has_isect = 0;
2430                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2431                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2432                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2433
2434                                                                 has_x_isect = 0;
2435                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2436                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2437                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2438
2439                                                                         /* test we're inside uvspace bucket and triangle bounds */
2440                                                                         if (isect_point_quad_v2(uv, seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3])) {
2441                                                                                 float fac;
2442
2443                                                                                 /* We need to find the closest point along the face edge,
2444                                                                                  * getting the screen_px_from_*** wont work because our actual location
2445                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2446                                                                                  * our location on the side of the face's UV */
2447 #if 0
2448                                                                                 if (is_ortho) screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2449                                                                                 else          screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2450 #endif
2451
2452                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2453                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2454
2455                                                                                 fac = line_point_factor_v2(uv, seam_subsection[0], seam_subsection[1]);
2456                                                                                 if      (fac < 0.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[0]); }
2457                                                                                 else if (fac > 1.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[1]); }
2458                                                                                 else                 { interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac); }
2459
2460                                                                                 if (!is_ortho) {
2461                                                                                         pixelScreenCo[3] = 1.0f;
2462                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2463                                                                                         pixelScreenCo[0] = (float)(ps->winx * 0.5f) + (ps->winx * 0.5f) * pixelScreenCo[0] / pixelScreenCo[3];
2464                                                                                         pixelScreenCo[1] = (float)(ps->winy * 0.5f) + (ps->winy * 0.5f) * pixelScreenCo[1] / pixelScreenCo[3];
2465                                                                                         pixelScreenCo[2] = pixelScreenCo[2] / pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2466                                                                                 }
2467
2468                                                                                 if ((ps->do_occlude == FALSE) ||
2469                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2470                                                                                 {
2471                                                                                         /* Only bother calculating the weights if we intersect */
2472                                                                                         if (ps->do_mask_normal || ps->dm_mtface_clone) {
2473 #if 1
2474                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2475                                                                                                 float uv_close[2];
2476                                                                                                 float uv_fac = closest_to_line_v2(uv_close, uv, tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2]);
2477                                                                                                 if      (uv_fac < 0.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx1]);
2478                                                                                                 else if (uv_fac > 1.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx2]);
2479
2480                                                                                                 if (side) {
2481                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[2], tf_uv_pxoffset[3], uv_close, w);
2482                                                                                                 }
2483                                                                                                 else {
2484                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[1], tf_uv_pxoffset[2], uv_close, w);
2485                                                                                                 }
2486 #else                                                                                   /* this is buggy with quads, don't use for now */
2487
2488                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2489                                                                                                 uv_fac = fac1 + (uv_fac * (fac2 - fac1));
2490
2491                                                                                                 w[0] = w[1] = w[2] = 0.0;
2492                                                                                                 if (side) {
2493                                                                                                         w[fidx1 ? fidx1 - 1 : 0] = 1.0f - uv_fac;
2494                                                                                                         w[fidx2 ? fidx2 - 1 : 0] = uv_fac;
2495                                                                                                 }
2496                                                                                                 else {
2497                                                                                                         w[fidx1] = 1.0f - uv_fac;
2498                                                                                                         w[fidx2] = uv_fac;
2499                                                                                                 }
2500 #endif
2501                                                                                         }
2502
2503                                                                                         /* a pity we need to get the worldspace pixel location here */
2504                                                                                         if (do_clip || do_3d_mapping) {
2505                                                                                                 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);
2506                                                                                                 else      interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
2507
2508                                                                                                 if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2509                                                                                                         continue; /* Watch out that no code below this needs to run */
2510                                                                                                 }
2511                                                                                         }
2512
2513                                                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2514
2515                                                                                         if (mask > 0.0f) {
2516                                                                                                 BLI_linklist_prepend_arena(
2517                                                                                                         bucketPixelNodes,
2518                                                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index, image_index, pixelScreenCo, wco, side, w),
2519                                                                                                         arena
2520                                                                                                         );
2521                                                                                         }
2522
2523                                                                                 }
2524                                                                         }
2525                                                                         else if (has_x_isect) {
2526                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2527                                                                                 break;
2528                                                                         }
2529                                                                 }
2530
2531 #if 0                           /* TODO - investigate why this dosnt work sometimes! it should! */
2532                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2533                                                                 if (has_x_isect == 0 && has_isect) {
2534                                                                         break;
2535                                                                 }
2536 #endif
2537                                                         }
2538                                                 }
2539                                         }
2540                                 }
2541                         }
2542                 }
2543         }
2544 #endif // PROJ_DEBUG_NOSEAMBLEED
2545 }
2546
2547
2548 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2549 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2550 {
2551         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2552         /* 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 */
2553         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 */
2554         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2555
2556         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2557         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2558
2559         /* in case the rect is outside the mesh 2d bounds */
2560         CLAMP(bucketMin[0], 0, ps->buckets_x);
2561         CLAMP(bucketMin[1], 0, ps->buckets_y);
2562
2563         CLAMP(bucketMax[0], 0, ps->buckets_x);
2564         CLAMP(bucketMax[1], 0, ps->buckets_y);
2565 }
2566
2567 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2568 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2569 {
2570         bucket_bounds->xmin = ps->screenMin[0] + ((bucket_x) * (ps->screen_width / ps->buckets_x));     /* left */
2571         bucket_bounds->xmax = ps->screenMin[0] + ((bucket_x + 1) * (ps->screen_width / ps->buckets_x)); /* right */
2572
2573         bucket_bounds->ymin = ps->screenMin[1] + ((bucket_y) * (ps->screen_height / ps->buckets_y));      /* bottom */
2574         bucket_bounds->ymax = ps->screenMin[1] + ((bucket_y + 1) * (ps->screen_height  / ps->buckets_y)); /* top */
2575 }
2576
2577 /* Fill this bucket with pixels from the faces that intersect it.
2578  *
2579  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2580 static void project_bucket_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, rctf *bucket_bounds)
2581 {
2582         LinkNode *node;
2583         int face_index, image_index = 0;
2584         ImBuf *ibuf = NULL;
2585         Image *tpage_last = NULL, *tpage;
2586         Image *ima = NULL;
2587
2588         if (ps->image_tot == 1) {
2589                 /* Simple loop, no context switching */
2590                 ibuf = ps->projImages[0].ibuf;
2591                 ima = ps->projImages[0].ima;
2592
2593                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2594                         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);
2595                 }
2596         }
2597         else {
2598
2599                 /* More complicated loop, switch between images */
2600                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2601                         face_index = GET_INT_FROM_POINTER(node->link);
2602
2603                         /* Image context switching */
2604                         tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
2605                         if (tpage_last != tpage) {
2606                                 tpage_last = tpage;
2607
2608                                 for (image_index = 0; image_index < ps->image_tot; image_index++) {
2609                                         if (ps->projImages[image_index].ima == tpage_last) {
2610                                                 ibuf = ps->projImages[image_index].ibuf;
2611                                                 ima = ps->projImages[image_index].ima;
2612                                                 break;
2613                                         }
2614                                 }
2615                         }
2616                         /* context switching done */
2617
2618                         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);
2619                 }
2620         }
2621
2622         ps->bucketFlags[bucket_index] |= PROJ_BUCKET_INIT;
2623 }
2624
2625
2626 /* We want to know if a bucket and a face overlap in screen-space
2627  *
2628  * Note, if this ever returns false positives its not that bad, since a face in the bounding area will have its pixels
2629  * calculated when it might not be needed later, (at the moment at least)
2630  * obviously it shouldn't have bugs though */
2631
2632 static int project_bucket_face_isect(ProjPaintState *ps, int bucket_x, int bucket_y, const MFace *mf)
2633 {
2634         /* TODO - replace this with a tricker method that uses sideofline for all screenCoords's edges against the closest bucket corner */
2635         rctf bucket_bounds;
2636         float p1[2], p2[2], p3[2], p4[2];
2637         float *v, *v1, *v2, *v3, *v4 = NULL;
2638         int fidx;
2639
2640         project_bucket_bounds(ps, bucket_x, bucket_y, &bucket_bounds);
2641
2642         /* Is one of the faces verts in the bucket bounds? */
2643
2644         fidx = mf->v4 ? 3 : 2;
2645         do {
2646                 v = ps->screenCoords[(*(&mf->v1 + fidx))];
2647                 if (BLI_rctf_isect_pt_v(&bucket_bounds, v)) {
2648                         return 1;
2649                 }
2650         } while (fidx--);
2651
2652         v1 = ps->screenCoords[mf->v1];
2653         v2 = ps->screenCoords[mf->v2];
2654         v3 = ps->screenCoords[mf->v3];
2655         if (mf->v4) {
2656                 v4 = ps->screenCoords[mf->v4];
2657         }
2658
2659         p1[0] = bucket_bounds.xmin; p1[1] = bucket_bounds.ymin;
2660         p2[0] = bucket_bounds.xmin; p2[1] = bucket_bounds.ymax;
2661         p3[0] = bucket_bounds.xmax; p3[1] = bucket_bounds.ymax;
2662         p4[0] = bucket_bounds.xmax; p4[1] = bucket_bounds.ymin;
2663
2664         if (mf->v4) {
2665                 if (isect_point_quad_v2(p1, v1, v2, v3, v4) ||
2666                     isect_point_quad_v2(p2, v1, v2, v3, v4) ||
2667                     isect_point_quad_v2(p3, v1, v2, v3, v4) ||
2668                     isect_point_quad_v2(p4, v1, v2, v3, v4) ||
2669
2670                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2671                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3) || isect_line_line_v2(p1, p2, v3, v4)) ||
2672                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3) || isect_line_line_v2(p2, p3, v3, v4)) ||
2673                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3) || isect_line_line_v2(p3, p4, v3, v4)) ||
2674                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3) || isect_line_line_v2(p4, p1, v3, v4)))
2675                 {
2676                         return 1;
2677                 }
2678         }
2679         else {
2680                 if (isect_point_tri_v2(p1, v1, v2, v3) ||
2681                     isect_point_tri_v2(p2, v1, v2, v3) ||
2682                     isect_point_tri_v2(p3, v1, v2, v3) ||
2683                     isect_point_tri_v2(p4, v1, v2, v3) ||
2684                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2685                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3)) ||
2686                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3)) ||
2687                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3)) ||
2688                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3)))
2689                 {
2690                         return 1;
2691                 }
2692         }
2693
2694         return 0;
2695 }
2696
2697 /* Add faces to the bucket but don't initialize its pixels
2698  * TODO - when painting occluded, sort the faces on their min-Z and only add faces that faces that are not occluded */
2699 static void project_paint_delayed_face_init(ProjPaintState *ps, const MFace *mf, const int face_index)
2700 {
2701         float min[2], max[2], *vCoSS;
2702         int bucketMin[2], bucketMax[2]; /* for  ps->bucketRect indexing */
2703         int fidx, bucket_x, bucket_y;
2704         int has_x_isect = -1, has_isect = 0; /* for early loop exit */
2705         MemArena *arena = ps->arena_mt[0]; /* just use the first thread arena since threading has not started yet */
2706
2707         INIT_MINMAX2(min, max);
2708
2709         fidx = mf->v4 ? 3 : 2;
2710         do {
2711                 vCoSS = ps->screenCoords[*(&mf->v1 + fidx)];
2712                 minmax_v2v2_v2(min, max, vCoSS);
2713         } while (fidx--);
2714
2715         project_paint_bucket_bounds(ps, min, max, bucketMin, bucketMax);
2716
2717         for (bucket_y = bucketMin[1]; bucket_y < bucketMax[1]; bucket_y++) {
2718                 has_x_isect = 0;
2719                 for (bucket_x = bucketMin[0]; bucket_x < bucketMax[0]; bucket_x++) {
2720                         if (project_bucket_face_isect(ps, bucket_x, bucket_y, mf)) {
2721                                 int bucket_index = bucket_x + (bucket_y * ps->buckets_x);
2722                                 BLI_linklist_prepend_arena(
2723                                         &ps->bucketFaces[bucket_index],
2724                                         SET_INT_IN_POINTER(face_index), /* cast to a pointer to shut up the compiler */
2725                                         arena
2726                                         );
2727
2728                                 has_x_isect = has_isect = 1;
2729                         }
2730                         else if (has_x_isect) {
2731                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2732                                 break;
2733                         }
2734                 }
2735
2736                 /* no intersection for this entire row, after some intersection above means we can quit now */
2737                 if (has_x_isect == 0 && has_isect) {
2738                         break;
2739                 }
2740         }
2741
2742 #ifndef PROJ_DEBUG_NOSEAMBLEED
2743         if (ps->seam_bleed_px > 0.0f) {
2744                 if (!mf->v4) {
2745                         ps->faceSeamFlags[face_index] |= PROJ_FACE_NOSEAM4; /* so this wont show up as an untagged edge */
2746                 }
2747                 **ps->faceSeamUVs[face_index] = FLT_MAX; /* set as uninitialized */
2748         }
2749 #endif
2750 }
2751
2752 /* run once per stroke before projection painting */
2753 static void project_paint_begin(ProjPaintState *ps)
2754 {
2755         /* Viewport vars */
2756         float mat[3][3];
2757
2758         float no[3];
2759
2760         float *projScreenCo; /* Note, we could have 4D vectors are only needed for */
2761         float projMargin;
2762
2763         /* Image Vars - keep track of images we have used */
2764         LinkNode *image_LinkList = NULL;
2765         LinkNode *node;
2766
2767         ProjPaintImage *projIma;
2768         Image *tpage_last = NULL, *tpage;
2769
2770         /* Face vars */
2771         MFace *mf;
2772         MTFace *tf;
2773
2774         int a, i; /* generic looping vars */
2775         int image_index = -1, face_index;
2776         MVert *mv;
2777
2778         MemArena *arena; /* at the moment this is just ps->arena_mt[0], but use this to show were not multithreading */
2779
2780         const int diameter = 2 * BKE_brush_size_get(ps->scene, ps->brush);
2781
2782         /* ---- end defines ---- */
2783
2784         if (ps->source == PROJ_SRC_VIEW)
2785                 ED_view3d_clipping_local(ps->rv3d, ps->ob->obmat);  /* faster clipping lookups */
2786
2787         /* paint onto the derived mesh */
2788
2789         /* Workaround for subsurf selection, try the display mesh first */
2790         if (ps->source == PROJ_SRC_IMAGE_CAM) {
2791                 /* using render mesh, assume only camera was rendered from */
2792                 ps->dm = mesh_create_derived_render(ps->scene, ps->ob, ps->scene->customdata_mask | CD_MASK_MTFACE);
2793                 ps->dm_release = TRUE;
2794         }
2795         else if (ps->ob->derivedFinal && CustomData_has_layer(&ps->ob->derivedFinal->faceData, CD_MTFACE)) {
2796                 ps->dm = ps->ob->derivedFinal;
2797                 ps->dm_release = FALSE;
2798         }
2799         else {
2800                 ps->dm = mesh_get_derived_final(ps->scene, ps->ob, ps->scene->customdata_mask | CD_MASK_MTFACE);
2801                 ps->dm_release = TRUE;
2802         }
2803
2804         if (!CustomData_has_layer(&ps->dm->faceData, CD_MTFACE) ) {
2805
2806                 if (ps->dm_release)
2807                         ps->dm->release(ps->dm);
2808
2809                 ps->dm = NULL;
2810                 return;
2811         }
2812
2813         ps->dm_mvert = ps->dm->getVertArray(ps->dm);
2814         ps->dm_mface = ps->dm->getTessFaceArray(ps->dm);
2815         ps->dm_mtface = ps->dm->getTessFaceDataArray(ps->dm, CD_MTFACE);
2816
2817         ps->dm_totvert = ps->dm->getNumVerts(ps->dm);
2818         ps->dm_totface = ps->dm->getNumTessFaces(ps->dm);
2819
2820         /* use clone mtface? */
2821
2822
2823         /* Note, use the original mesh for getting the clone and mask layer index
2824          * this avoids re-generating the derived mesh just to get the new index */
2825         if (ps->do_layer_clone) {
2826                 //int layer_num = CustomData_get_clone_layer(&ps->dm->faceData, CD_MTFACE);
2827                 int layer_num = CustomData_get_clone_layer(&((Mesh *)ps->ob->data)->fdata, CD_MTFACE);
2828                 if (layer_num != -1)
2829                         ps->dm_mtface_clone = CustomData_get_layer_n(&ps->dm->faceData, CD_MTFACE, layer_num);
2830
2831                 if (ps->dm_mtface_clone == NULL || ps->dm_mtface_clone == ps->dm_mtface) {
2832                         ps->do_layer_clone = FALSE;
2833                         ps->dm_mtface_clone = NULL;
2834                         printf("ACK!\n");
2835                 }
2836         }
2837
2838         if (ps->do_layer_stencil) {
2839                 //int layer_num = CustomData_get_stencil_layer(&ps->dm->faceData, CD_MTFACE);
2840                 int layer_num = CustomData_get_stencil_layer(&((Mesh *)ps->ob->data)->fdata, CD_MTFACE);
2841                 if (layer_num != -1)
2842                         ps->dm_mtface_stencil = CustomData_get_layer_n(&ps->dm->faceData, CD_MTFACE, layer_num);
2843
2844                 if (ps->dm_mtface_stencil == NULL || ps->dm_mtface_stencil == ps->dm_mtface) {
2845                         ps->do_layer_stencil = FALSE;
2846                         ps->dm_mtface_stencil = NULL;
2847                 }
2848         }
2849
2850         /* when using subsurf or multires, mface arrays are thrown away, we need to keep a copy */
2851         if (ps->dm->type != DM_TYPE_CDDM) {
2852                 ps->dm_mvert = MEM_dupallocN(ps->dm_mvert);
2853                 ps->dm_mface = MEM_dupallocN(ps->dm_mface);
2854                 /* looks like these are ok for now.*/
2855 #if 0
2856                 ps->dm_mtface = MEM_dupallocN(ps->dm_mtface);
2857                 ps->dm_mtface_clone = MEM_dupallocN(ps->dm_mtface_clone);
2858                 ps->dm_mtface_stencil = MEM_dupallocN(ps->dm_mtface_stencil);
2859 #endif
2860         }
2861
2862         ps->viewDir[0] = 0.0f;
2863         ps->viewDir[1] = 0.0f;
2864         ps->viewDir[2] = 1.0f;
2865
2866         {
2867                 float viewmat[4][4];
2868                 float viewinv[4][4];
2869
2870                 invert_m4_m4(ps->ob->imat, ps->ob->obmat);
2871
2872                 if (ps->source == PROJ_SRC_VIEW) {
2873                         /* normal drawing */
2874                         ps->winx = ps->ar->winx;
2875                         ps->winy = ps->ar->winy;
2876
2877                         copy_m4_m4(viewmat, ps->rv3d->viewmat);
2878                         copy_m4_m4(viewinv, ps->rv3d->viewinv);
2879
2880                         ED_view3d_ob_project_mat_get(ps->rv3d, ps->ob, ps->projectMat);
2881
2882                         ps->is_ortho = ED_view3d_clip_range_get(ps->v3d, ps->rv3d, &ps->clipsta, &ps->clipend, true);
2883                 }
2884                 else {<