d6989c082a101ca6575b01a050bba281d02b7872
[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 #define PROJ_PIXEL_TOLERANCE 0.01f
168
169 /* vert flags */
170 #define PROJ_VERT_CULL 1
171
172 /* This is mainly a convenience struct used so we can keep an array of images we use
173  * Thir imbufs, etc, in 1 array, When using threads this array is copied for each thread
174  * because 'partRedrawRect' and 'touch' values would not be thread safe */
175 typedef struct ProjPaintImage {
176         Image *ima;
177         ImBuf *ibuf;
178         ImagePaintPartialRedraw *partRedrawRect;
179         void **undoRect; /* only used to build undo tiles after painting */
180         int touch;
181 } ProjPaintImage;
182
183 /* Main projection painting struct passed to all projection painting functions */
184 typedef struct ProjPaintState {
185         View3D *v3d;
186         RegionView3D *rv3d;
187         ARegion *ar;
188         Scene *scene;
189         int source; /* PROJ_SRC_**** */
190
191         Brush *brush;
192         short tool, blend, mode;
193         int orig_brush_size;
194         Object *ob;
195         /* end similarities with ImagePaintState */
196
197         DerivedMesh    *dm;
198         int dm_totface;
199         int dm_totvert;
200         int dm_release;
201
202         MVert          *dm_mvert;
203         MFace          *dm_mface;
204         MTFace         *dm_mtface;
205         MTFace         *dm_mtface_clone;    /* other UV map, use for cloning between layers */
206         MTFace         *dm_mtface_stencil;
207
208         /* projection painting only */
209         MemArena *arena_mt[BLENDER_MAX_THREADS]; /* for multithreading, the first item is sometimes used for non threaded cases too */
210         LinkNode **bucketRect;              /* screen sized 2D array, each pixel has a linked list of ProjPixel's */
211         LinkNode **bucketFaces;             /* bucketRect aligned array linkList of faces overlapping each bucket */
212         unsigned char *bucketFlags;         /* store if the bucks have been initialized  */
213 #ifndef PROJ_DEBUG_NOSEAMBLEED
214         char *faceSeamFlags;                /* store info about faces, if they are initialized etc*/
215         float (*faceSeamUVs)[4][2];         /* expanded UVs for faces to use as seams */
216         LinkNode **vertFaces;               /* Only needed for when seam_bleed_px is enabled, use to find UV seams */
217 #endif
218         char *vertFlags;                    /* store options per vert, now only store if the vert is pointing away from the view */
219         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 */
220         int buckets_y;
221
222         ProjPaintImage *projImages;
223
224         int pixel_sizeof;           /* result of project_paint_pixel_sizeof(), constant per stroke */
225
226         int image_tot;              /* size of projectImages array */
227
228         float (*screenCoords)[4];   /* verts projected into floating point screen space */
229
230         float screenMin[2];         /* 2D bounds for mesh verts on the screen's plane (screenspace) */
231         float screenMax[2];
232         float screen_width;         /* Calculated from screenMin & screenMax */
233         float screen_height;
234         int winx, winy;             /* from the carea or from the projection render */
235
236         /* options for projection painting */
237         int do_layer_clone;
238         int do_layer_stencil;
239         int do_layer_stencil_inv;
240
241         short do_occlude;               /* Use raytraced occlusion? - ortherwise will paint right through to the back*/
242         short do_backfacecull;          /* ignore faces with normals pointing away, skips a lot of raycasts if your normals are correctly flipped */
243         short do_mask_normal;           /* mask out pixels based on their normals */
244         short do_new_shading_nodes;     /* cache BKE_scene_use_new_shading_nodes value */
245         float normal_angle;             /* what angle to mask at*/
246         float normal_angle_inner;
247         float normal_angle_range;       /* difference between normal_angle and normal_angle_inner, for easy access */
248
249         bool do_face_sel;               /* quick access to (me->editflag & ME_EDIT_PAINT_FACE_SEL) */
250         bool is_ortho;
251         bool do_masking;              /* use masking during painting. Some operations such as airbrush may disable */
252         bool is_texbrush;              /* only to avoid running  */
253         bool is_maskbrush;            /* mask brush is applied before masking */
254         bool is_maskbrush_tiled;      /* mask brush is applied after masking */
255 #ifndef PROJ_DEBUG_NOSEAMBLEED
256         float seam_bleed_px;
257 #endif
258         /* clone vars */
259         float cloneOffset[2];
260
261         float projectMat[4][4];     /* Projection matrix, use for getting screen coords */
262         float viewDir[3];           /* View vector, use for do_backfacecull and for ray casting with an ortho viewport  */
263         float viewPos[3];           /* View location in object relative 3D space, so can compare to verts  */
264         float clipsta, clipend;
265
266         /* reproject vars */
267         Image *reproject_image;
268         ImBuf *reproject_ibuf;
269
270         /* threads */
271         int thread_tot;
272         int bucketMin[2];
273         int bucketMax[2];
274         int context_bucket_x, context_bucket_y; /* must lock threads while accessing these */
275
276         /* redraw */
277         bool need_redraw;
278 } ProjPaintState;
279
280 typedef union pixelPointer {
281         float *f_pt;            /* float buffer */
282         unsigned int *uint_pt; /* 2 ways to access a char buffer */
283         unsigned char *ch_pt;
284 } PixelPointer;
285
286 typedef union pixelStore {
287         unsigned char ch[4];
288         unsigned int uint;
289         float f[4];
290 } PixelStore;
291
292 typedef struct ProjPixel {
293         float projCoSS[2]; /* the floating point screen projection of this pixel */
294         float worldCoSS[3];
295         /* Only used when the airbrush is disabled.
296          * Store the max mask value to avoid painting over an area with a lower opacity
297          * with an advantage that we can avoid touching the pixel at all, if the
298          * new mask value is lower then mask_accum */
299         unsigned short mask_accum;
300
301         /* for various reasons we may want to mask out painting onto this pixel */
302         unsigned short mask;
303
304         short x_px, y_px;
305
306         PixelStore origColor;
307         PixelStore newColor;
308         PixelPointer pixel;
309
310         short image_index; /* if anyone wants to paint onto more than 32768 images they can bite me */
311         unsigned char bb_cell_index;
312 } ProjPixel;
313
314 typedef struct ProjPixelClone {
315         struct ProjPixel __pp;
316         PixelStore clonepx;
317 } ProjPixelClone;
318
319 /* blur, store surrounding colors */
320 #define PROJ_PIXEL_SOFTEN_TOT 4
321 /* blur picking offset (in screenspace) */
322 #define PROJ_PIXEL_SOFTEN_OFS_PX 1.0f
323
324 static const float proj_pixel_soften_v2[PROJ_PIXEL_SOFTEN_TOT][2] = {
325         {-PROJ_PIXEL_SOFTEN_OFS_PX,                         0.0f},
326         { 0.0f,                        -PROJ_PIXEL_SOFTEN_OFS_PX},
327         { 0.0f,                         PROJ_PIXEL_SOFTEN_OFS_PX},
328         { PROJ_PIXEL_SOFTEN_OFS_PX,                         0.0f},
329 };
330
331 /* Finish projection painting structs */
332
333 static Image *project_paint_face_image(const ProjPaintState *ps, MTFace *dm_mtface, int face_index)
334 {
335         Image *ima;
336
337         if (ps->do_new_shading_nodes) { /* cached BKE_scene_use_new_shading_nodes result */
338                 MFace *mf = ps->dm_mface + face_index;
339                 ED_object_get_active_image(ps->ob, mf->mat_nr + 1, &ima, NULL, NULL);
340         }
341         else {
342                 ima = dm_mtface[face_index].tpage;
343         }
344
345         return ima;
346 }
347
348 /* fast projection bucket array lookup, use the safe version for bound checking  */
349 static int project_bucket_offset(const ProjPaintState *ps, const float projCoSS[2])
350 {
351         /* If we were not dealing with screenspace 2D coords we could simple do...
352          * ps->bucketRect[x + (y*ps->buckets_y)] */
353
354         /* please explain?
355          * projCoSS[0] - ps->screenMin[0]   : zero origin
356          * ... / ps->screen_width           : range from 0.0 to 1.0
357          * ... * ps->buckets_x              : use as a bucket index
358          *
359          * Second multiplication does similar but for vertical offset
360          */
361         return ( (int)(((projCoSS[0] - ps->screenMin[0]) / ps->screen_width)  * ps->buckets_x)) +
362                (((int)(((projCoSS[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y)) * ps->buckets_x);
363 }
364
365 static int project_bucket_offset_safe(const ProjPaintState *ps, const float projCoSS[2])
366 {
367         int bucket_index = project_bucket_offset(ps, projCoSS);
368
369         if (bucket_index < 0 || bucket_index >= ps->buckets_x * ps->buckets_y) {
370                 return -1;
371         }
372         else {
373                 return bucket_index;
374         }
375 }
376
377 /* still use 2D X,Y space but this works for verts transformed by a perspective matrix, using their 4th component as a weight */
378 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])
379 {
380         float wtot_inv, wtot;
381
382         w[0] = area_tri_signed_v2(v2, v3, co) / v1[3];
383         w[1] = area_tri_signed_v2(v3, v1, co) / v2[3];
384         w[2] = area_tri_signed_v2(v1, v2, co) / v3[3];
385         wtot = w[0] + w[1] + w[2];
386
387         if (wtot != 0.0f) {
388                 wtot_inv = 1.0f / wtot;
389
390                 w[0] = w[0] * wtot_inv;
391                 w[1] = w[1] * wtot_inv;
392                 w[2] = w[2] * wtot_inv;
393         }
394         else /* dummy values for zero area face */
395                 w[0] = w[1] = w[2] = 1.0f / 3.0f;
396 }
397
398 static float VecZDepthOrtho(const float pt[2],
399                             const float v1[3], const float v2[3], const float v3[3],
400                             float w[3])
401 {
402         barycentric_weights_v2(v1, v2, v3, pt, w);
403         return (v1[2] * w[0]) + (v2[2] * w[1]) + (v3[2] * w[2]);
404 }
405
406 static float VecZDepthPersp(const float pt[2],
407                             const float v1[4], const float v2[4], const float v3[4],
408                             float w[3])
409 {
410         float wtot_inv, wtot;
411         float w_tmp[3];
412
413         barycentric_weights_v2_persp(v1, v2, v3, pt, w);
414         /* for the depth we need the weights to match what
415          * barycentric_weights_v2 would return, in this case its easiest just to
416          * undo the 4th axis division and make it unit-sum
417          *
418          * don't call barycentric_weights_v2() because our callers expect 'w'
419          * to be weighted from the perspective */
420         w_tmp[0] = w[0] * v1[3];
421         w_tmp[1] = w[1] * v2[3];
422         w_tmp[2] = w[2] * v3[3];
423
424         wtot = w_tmp[0] + w_tmp[1] + w_tmp[2];
425
426         if (wtot != 0.0f) {
427                 wtot_inv = 1.0f / wtot;
428
429                 w_tmp[0] = w_tmp[0] * wtot_inv;
430                 w_tmp[1] = w_tmp[1] * wtot_inv;
431                 w_tmp[2] = w_tmp[2] * wtot_inv;
432         }
433         else /* dummy values for zero area face */
434                 w_tmp[0] = w_tmp[1] = w_tmp[2] = 1.0f / 3.0f;
435         /* done mimicing barycentric_weights_v2() */
436
437         return (v1[2] * w_tmp[0]) + (v2[2] * w_tmp[1]) + (v3[2] * w_tmp[2]);
438 }
439
440
441 /* Return the top-most face index that the screen space coord 'pt' touches (or -1) */
442 static int project_paint_PickFace(const ProjPaintState *ps, const float pt[2], float w[3], int *side)
443 {
444         LinkNode *node;
445         float w_tmp[3];
446         float *v1, *v2, *v3, *v4;
447         int bucket_index;
448         int face_index;
449         int best_side = -1;
450         int best_face_index = -1;
451         float z_depth_best = FLT_MAX, z_depth;
452         MFace *mf;
453
454         bucket_index = project_bucket_offset_safe(ps, pt);
455         if (bucket_index == -1)
456                 return -1;
457
458
459
460         /* we could return 0 for 1 face buckets, as long as this function assumes
461          * that the point its testing is only every originated from an existing face */
462
463         for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
464                 face_index = GET_INT_FROM_POINTER(node->link);
465                 mf = ps->dm_mface + face_index;
466
467                 v1 = ps->screenCoords[mf->v1];
468                 v2 = ps->screenCoords[mf->v2];
469                 v3 = ps->screenCoords[mf->v3];
470
471                 if (isect_point_tri_v2(pt, v1, v2, v3)) {
472                         if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v2, v3, w_tmp);
473                         else z_depth = VecZDepthPersp(pt, v1, v2, v3, w_tmp);
474
475                         if (z_depth < z_depth_best) {
476                                 best_face_index = face_index;
477                                 best_side = 0;
478                                 z_depth_best = z_depth;
479                                 copy_v3_v3(w, w_tmp);
480                         }
481                 }
482                 else if (mf->v4) {
483                         v4 = ps->screenCoords[mf->v4];
484
485                         if (isect_point_tri_v2(pt, v1, v3, v4)) {
486                                 if (ps->is_ortho) z_depth = VecZDepthOrtho(pt, v1, v3, v4, w_tmp);
487                                 else z_depth = VecZDepthPersp(pt, v1, v3, v4, w_tmp);
488
489                                 if (z_depth < z_depth_best) {
490                                         best_face_index = face_index;
491                                         best_side = 1;
492                                         z_depth_best = z_depth;
493                                         copy_v3_v3(w, w_tmp);
494                                 }
495                         }
496                 }
497         }
498
499         *side = best_side;
500         return best_face_index; /* will be -1 or a valid face */
501 }
502
503 /* Converts a uv coord into a pixel location wrapping if the uv is outside 0-1 range */
504 static void uvco_to_wrapped_pxco(const float uv[2], int ibuf_x, int ibuf_y, float *x, float *y)
505 {
506         /* use */
507         *x = (float)fmodf(uv[0], 1.0f);
508         *y = (float)fmodf(uv[1], 1.0f);
509
510         if (*x < 0.0f) *x += 1.0f;
511         if (*y < 0.0f) *y += 1.0f;
512
513         *x = *x * ibuf_x - 0.5f;
514         *y = *y * ibuf_y - 0.5f;
515 }
516
517 /* Set the top-most face color that the screen space coord 'pt' touches (or return 0 if none touch) */
518 static bool project_paint_PickColor(const ProjPaintState *ps, const float pt[2],
519                                     float *rgba_fp, unsigned char *rgba, const bool interp)
520 {
521         float w[3], uv[2];
522         int side;
523         int face_index;
524         MTFace *tf;
525         Image *ima;
526         ImBuf *ibuf;
527         int xi, yi;
528
529
530         face_index = project_paint_PickFace(ps, pt, w, &side);
531
532         if (face_index == -1)
533                 return 0;
534
535         tf = ps->dm_mtface + face_index;
536
537         if (side == 0) {
538                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[1], tf->uv[2], w);
539         }
540         else { /* QUAD */
541                 interp_v2_v2v2v2(uv, tf->uv[0], tf->uv[2], tf->uv[3], w);
542         }
543
544         ima = project_paint_face_image(ps, ps->dm_mtface, face_index);
545         ibuf = ima->ibufs.first; /* we must have got the imbuf before getting here */
546         if (!ibuf) return 0;
547
548         if (interp) {
549                 float x, y;
550                 uvco_to_wrapped_pxco(uv, ibuf->x, ibuf->y, &x, &y);
551
552                 if (ibuf->rect_float) {
553                         if (rgba_fp) {
554                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_fp, x, y);
555                         }
556                         else {
557                                 float rgba_tmp_f[4];
558                                 bilinear_interpolation_color_wrap(ibuf, NULL, rgba_tmp_f, x, y);
559                                 premul_float_to_straight_uchar(rgba, rgba_tmp_f);
560                         }
561                 }
562                 else {
563                         if (rgba) {
564                                 bilinear_interpolation_color_wrap(ibuf, rgba, NULL, x, y);
565                         }
566                         else {
567                                 unsigned char rgba_tmp[4];
568                                 bilinear_interpolation_color_wrap(ibuf, rgba_tmp, NULL, x, y);
569                                 straight_uchar_to_premul_float(rgba_fp, rgba_tmp);
570                         }
571                 }
572         }
573         else {
574                 //xi = (int)((uv[0]*ibuf->x) + 0.5f);
575                 //yi = (int)((uv[1]*ibuf->y) + 0.5f);
576                 //if (xi < 0 || xi >= ibuf->x  ||  yi < 0 || yi >= ibuf->y) return 0;
577
578                 /* wrap */
579                 xi = mod_i((int)(uv[0] * ibuf->x), ibuf->x);
580                 yi = mod_i((int)(uv[1] * ibuf->y), ibuf->y);
581
582                 if (rgba) {
583                         if (ibuf->rect_float) {
584                                 float *rgba_tmp_fp = ibuf->rect_float + (xi + yi * ibuf->x * 4);
585                                 premul_float_to_straight_uchar(rgba, rgba_tmp_fp);
586                         }
587                         else {
588                                 *((unsigned int *)rgba) = *(unsigned int *)(((char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4));
589                         }
590                 }
591
592                 if (rgba_fp) {
593                         if (ibuf->rect_float) {
594                                 copy_v4_v4(rgba_fp, (ibuf->rect_float + ((xi + yi * ibuf->x) * 4)));
595                         }
596                         else {
597                                 unsigned char *tmp_ch = ((unsigned char *)ibuf->rect) + ((xi + yi * ibuf->x) * 4);
598                                 straight_uchar_to_premul_float(rgba_fp, tmp_ch);
599                         }
600                 }
601         }
602         return 1;
603 }
604
605 /* Check if 'pt' is infront of the 3 verts on the Z axis (used for screenspace occlusuion test)
606  * return...
607  *  0   : no occlusion
608  * -1   : no occlusion but 2D intersection is true (avoid testing the other half of a quad)
609  *  1   : occluded
610  *  2   : occluded with w[3] weights set (need to know in some cases) */
611
612 static int project_paint_occlude_ptv(const float pt[3],
613                                      const float v1[4], const float v2[4], const float v3[4],
614                                      float w[3], const bool is_ortho)
615 {
616         /* if all are behind us, return false */
617         if (v1[2] > pt[2] && v2[2] > pt[2] && v3[2] > pt[2])
618                 return 0;
619
620         /* do a 2D point in try intersection */
621         if (!isect_point_tri_v2(pt, v1, v2, v3))
622                 return 0;  /* we know there is  */
623
624
625         /* From here on we know there IS an intersection */
626         /* if ALL of the verts are infront of us then we know it intersects ? */
627         if (v1[2] < pt[2] && v2[2] < pt[2] && v3[2] < pt[2]) {
628                 return 1;
629         }
630         else {
631                 /* we intersect? - find the exact depth at the point of intersection */
632                 /* Is this point is occluded by another face? */
633                 if (is_ortho) {
634                         if (VecZDepthOrtho(pt, v1, v2, v3, w) < pt[2]) return 2;
635                 }
636                 else {
637                         if (VecZDepthPersp(pt, v1, v2, v3, w) < pt[2]) return 2;
638                 }
639         }
640         return -1;
641 }
642
643
644 static int project_paint_occlude_ptv_clip(const ProjPaintState *ps, const MFace *mf,
645                                           const float pt[3], const float v1[4], const float v2[4], const float v3[4],
646                                           const int side)
647 {
648         float w[3], wco[3];
649         int ret = project_paint_occlude_ptv(pt, v1, v2, v3, w, ps->is_ortho);
650
651         if (ret <= 0)
652                 return ret;
653
654         if (ret == 1) { /* weights not calculated */
655                 if (ps->is_ortho) barycentric_weights_v2(v1, v2, v3, pt, w);
656                 else barycentric_weights_v2_persp(v1, v2, v3, pt, w);
657         }
658
659         /* Test if we're in the clipped area, */
660         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);
661         else interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
662
663         if (!ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
664                 return 1;
665         }
666
667         return -1;
668 }
669
670
671 /* Check if a screenspace location is occluded by any other faces
672  * check, pixelScreenCo must be in screenspace, its Z-Depth only needs to be used for comparison
673  * and doesn't need to be correct in relation to X and Y coords (this is the case in perspective view) */
674 static bool project_bucket_point_occluded(const ProjPaintState *ps, LinkNode *bucketFace,
675                                           const int orig_face, const float pixelScreenCo[4])
676 {
677         MFace *mf;
678         int face_index;
679         int isect_ret;
680         float w[3]; /* not needed when clipping */
681         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
682
683         /* we could return 0 for 1 face buckets, as long as this function assumes
684          * that the point its testing is only every originated from an existing face */
685
686         for (; bucketFace; bucketFace = bucketFace->next) {
687                 face_index = GET_INT_FROM_POINTER(bucketFace->link);
688
689                 if (orig_face != face_index) {
690                         mf = ps->dm_mface + face_index;
691                         if (do_clip)
692                                 isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], 0);
693                         else
694                                 isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v2], ps->screenCoords[mf->v3], w, ps->is_ortho);
695
696                         /* Note, if (isect_ret == -1) then we don't want to test the other side of the quad */
697                         if (isect_ret == 0 && mf->v4) {
698                                 if (do_clip)
699                                         isect_ret = project_paint_occlude_ptv_clip(ps, mf, pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], 1);
700                                 else
701                                         isect_ret = project_paint_occlude_ptv(pixelScreenCo, ps->screenCoords[mf->v1], ps->screenCoords[mf->v3], ps->screenCoords[mf->v4], w, ps->is_ortho);
702                         }
703                         if (isect_ret >= 1) {
704                                 /* TODO - we may want to cache the first hit,
705                                  * it is not possible to swap the face order in the list anymore */
706                                 return true;
707                         }
708                 }
709         }
710         return false;
711 }
712
713 /* basic line intersection, could move to math_geom.c, 2 points with a horiz line
714  * 1 for an intersection, 2 if the first point is aligned, 3 if the second point is aligned */
715 #define ISECT_TRUE 1
716 #define ISECT_TRUE_P1 2
717 #define ISECT_TRUE_P2 3
718 static int line_isect_y(const float p1[2], const float p2[2], const float y_level, float *x_isect)
719 {
720         float y_diff;
721
722         if (y_level == p1[1]) { /* are we touching the first point? - no interpolation needed */
723                 *x_isect = p1[0];
724                 return ISECT_TRUE_P1;
725         }
726         if (y_level == p2[1]) { /* are we touching the second point? - no interpolation needed */
727                 *x_isect = p2[0];
728                 return ISECT_TRUE_P2;
729         }
730
731         y_diff = fabsf(p1[1] - p2[1]); /* yuck, horizontal line, we cant do much here */
732
733         if (y_diff < 0.000001f) {
734                 *x_isect = (p1[0] + p2[0]) * 0.5f;
735                 return ISECT_TRUE;
736         }
737
738         if (p1[1] > y_level && p2[1] < y_level) {
739                 *x_isect = (p2[0] * (p1[1] - y_level) + p1[0] * (y_level - p2[1])) / y_diff;  /*(p1[1]-p2[1]);*/
740                 return ISECT_TRUE;
741         }
742         else if (p1[1] < y_level && p2[1] > y_level) {
743                 *x_isect = (p2[0] * (y_level - p1[1]) + p1[0] * (p2[1] - y_level)) / y_diff;  /*(p2[1]-p1[1]);*/
744                 return ISECT_TRUE;
745         }
746         else {
747                 return 0;
748         }
749 }
750
751 static int line_isect_x(const float p1[2], const float p2[2], const float x_level, float *y_isect)
752 {
753         float x_diff;
754
755         if (x_level == p1[0]) { /* are we touching the first point? - no interpolation needed */
756                 *y_isect = p1[1];
757                 return ISECT_TRUE_P1;
758         }
759         if (x_level == p2[0]) { /* are we touching the second point? - no interpolation needed */
760                 *y_isect = p2[1];
761                 return ISECT_TRUE_P2;
762         }
763
764         x_diff = fabsf(p1[0] - p2[0]); /* yuck, horizontal line, we cant do much here */
765
766         if (x_diff < 0.000001f) { /* yuck, vertical line, we cant do much here */
767                 *y_isect = (p1[0] + p2[0]) * 0.5f;
768                 return ISECT_TRUE;
769         }
770
771         if (p1[0] > x_level && p2[0] < x_level) {
772                 *y_isect = (p2[1] * (p1[0] - x_level) + p1[1] * (x_level - p2[0])) / x_diff; /*(p1[0]-p2[0]);*/
773                 return ISECT_TRUE;
774         }
775         else if (p1[0] < x_level && p2[0] > x_level) {
776                 *y_isect = (p2[1] * (x_level - p1[0]) + p1[1] * (p2[0] - x_level)) / x_diff; /*(p2[0]-p1[0]);*/
777                 return ISECT_TRUE;
778         }
779         else {
780                 return 0;
781         }
782 }
783
784 /* simple func use for comparing UV locations to check if there are seams.
785  * Its possible this gives incorrect results, when the UVs for 1 face go into the next
786  * tile, but do not do this for the adjacent face, it could return a false positive.
787  * This is so unlikely that Id not worry about it. */
788 #ifndef PROJ_DEBUG_NOSEAMBLEED
789 static bool cmp_uv(const float vec2a[2], const float vec2b[2])
790 {
791         /* if the UV's are not between 0.0 and 1.0 */
792         float xa = (float)fmodf(vec2a[0], 1.0f);
793         float ya = (float)fmodf(vec2a[1], 1.0f);
794
795         float xb = (float)fmodf(vec2b[0], 1.0f);
796         float yb = (float)fmodf(vec2b[1], 1.0f);
797
798         if (xa < 0.0f) xa += 1.0f;
799         if (ya < 0.0f) ya += 1.0f;
800
801         if (xb < 0.0f) xb += 1.0f;
802         if (yb < 0.0f) yb += 1.0f;
803
804         return ((fabsf(xa - xb) < PROJ_GEOM_TOLERANCE) && (fabsf(ya - yb) < PROJ_GEOM_TOLERANCE)) ? 1 : 0;
805 }
806 #endif
807
808 /* set min_px and max_px to the image space bounds of the UV coords
809  * return zero if there is no area in the returned rectangle */
810 #ifndef PROJ_DEBUG_NOSEAMBLEED
811 static bool pixel_bounds_uv(
812         const float uv1[2], const float uv2[2], const float uv3[2], const float uv4[2],
813         rcti *bounds_px,
814         const int ibuf_x, const int ibuf_y,
815         const bool is_quad
816         )
817 {
818         float min_uv[2], max_uv[2]; /* UV bounds */
819
820         INIT_MINMAX2(min_uv, max_uv);
821
822         minmax_v2v2_v2(min_uv, max_uv, uv1);
823         minmax_v2v2_v2(min_uv, max_uv, uv2);
824         minmax_v2v2_v2(min_uv, max_uv, uv3);
825         if (is_quad)
826                 minmax_v2v2_v2(min_uv, max_uv, uv4);
827
828         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
829         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
830
831         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
832         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
833
834         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
835
836         /* face uses no UV area when quantized to pixels? */
837         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
838 }
839 #endif
840
841 static bool pixel_bounds_array(float (*uv)[2], rcti *bounds_px, const int ibuf_x, const int ibuf_y, int tot)
842 {
843         float min_uv[2], max_uv[2]; /* UV bounds */
844
845         if (tot == 0) {
846                 return 0;
847         }
848
849         INIT_MINMAX2(min_uv, max_uv);
850
851         while (tot--) {
852                 minmax_v2v2_v2(min_uv, max_uv, (*uv));
853                 uv++;
854         }
855
856         bounds_px->xmin = (int)(ibuf_x * min_uv[0]);
857         bounds_px->ymin = (int)(ibuf_y * min_uv[1]);
858
859         bounds_px->xmax = (int)(ibuf_x * max_uv[0]) + 1;
860         bounds_px->ymax = (int)(ibuf_y * max_uv[1]) + 1;
861
862         /*printf("%d %d %d %d\n", min_px[0], min_px[1], max_px[0], max_px[1]);*/
863
864         /* face uses no UV area when quantized to pixels? */
865         return (bounds_px->xmin == bounds_px->xmax || bounds_px->ymin == bounds_px->ymax) ? 0 : 1;
866 }
867
868 #ifndef PROJ_DEBUG_NOSEAMBLEED
869
870 /* This function returns 1 if this face has a seam along the 2 face-vert indices
871  * 'orig_i1_fidx' and 'orig_i2_fidx' */
872 static bool check_seam(const ProjPaintState *ps,
873                        const int orig_face, const int orig_i1_fidx, const int orig_i2_fidx,
874                        int *other_face, int *orig_fidx)
875 {
876         LinkNode *node;
877         int face_index;
878         unsigned int i1, i2;
879         int i1_fidx = -1, i2_fidx = -1; /* index in face */
880         MFace *mf;
881         MTFace *tf;
882         const MFace *orig_mf = ps->dm_mface + orig_face;
883         const MTFace *orig_tf = ps->dm_mtface + orig_face;
884
885         /* vert indices from face vert order indices */
886         i1 = (*(&orig_mf->v1 + orig_i1_fidx));
887         i2 = (*(&orig_mf->v1 + orig_i2_fidx));
888
889         for (node = ps->vertFaces[i1]; node; node = node->next) {
890                 face_index = GET_INT_FROM_POINTER(node->link);
891
892                 if (face_index != orig_face) {
893                         mf = ps->dm_mface + face_index;
894                         /* could check if the 2 faces images match here,
895                          * but then there wouldn't be a way to return the opposite face's info */
896
897
898                         /* We need to know the order of the verts in the adjacent face
899                          * set the i1_fidx and i2_fidx to (0,1,2,3) */
900                         if      (mf->v1 == i1) i1_fidx = 0;
901                         else if (mf->v2 == i1) i1_fidx = 1;
902                         else if (mf->v3 == i1) i1_fidx = 2;
903                         else if (mf->v4 && mf->v4 == i1) i1_fidx = 3;
904
905                         if      (mf->v1 == i2) i2_fidx = 0;
906                         else if (mf->v2 == i2) i2_fidx = 1;
907                         else if (mf->v3 == i2) i2_fidx = 2;
908                         else if (mf->v4 && mf->v4 == i2) i2_fidx = 3;
909
910                         /* Only need to check if 'i2_fidx' is valid because we know i1_fidx is the same vert on both faces */
911                         if (i2_fidx != -1) {
912                                 Image *tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
913                                 Image *orig_tpage = project_paint_face_image(ps, ps->dm_mtface, orig_face);
914
915                                 /* This IS an adjacent face!, now lets check if the UVs are ok */
916                                 tf = ps->dm_mtface + face_index;
917
918                                 /* set up the other face */
919                                 *other_face = face_index;
920                                 *orig_fidx = (i1_fidx < i2_fidx) ? i1_fidx : i2_fidx;
921
922                                 /* first test if they have the same image */
923                                 if ((orig_tpage == tpage) &&
924                                     cmp_uv(orig_tf->uv[orig_i1_fidx], tf->uv[i1_fidx]) &&
925                                     cmp_uv(orig_tf->uv[orig_i2_fidx], tf->uv[i2_fidx]) )
926                                 {
927                                         // printf("SEAM (NONE)\n");
928                                         return 0;
929
930                                 }
931                                 else {
932                                         // printf("SEAM (UV GAP)\n");
933                                         return 1;
934                                 }
935                         }
936                 }
937         }
938         // printf("SEAM (NO FACE)\n");
939         *other_face = -1;
940         return 1;
941 }
942
943 /* Calculate outset UV's, this is not the same as simply scaling the UVs,
944  * since the outset coords are a margin that keep an even distance from the original UV's,
945  * note that the image aspect is taken into account */
946 static void uv_image_outset(float (*orig_uv)[2], float (*outset_uv)[2], const float scaler,
947                             const int ibuf_x, const int ibuf_y, const bool is_quad)
948 {
949         float a1, a2, a3, a4 = 0.0f;
950         float puv[4][2]; /* pixelspace uv's */
951         float no1[2], no2[2], no3[2], no4[2]; /* normals */
952         float dir1[2], dir2[2], dir3[2], dir4[2];
953         float ibuf_inv[2];
954
955         ibuf_inv[0] = 1.0f / (float)ibuf_x;
956         ibuf_inv[1] = 1.0f / (float)ibuf_y;
957
958         /* make UV's in pixel space so we can */
959         puv[0][0] = orig_uv[0][0] * ibuf_x;
960         puv[0][1] = orig_uv[0][1] * ibuf_y;
961
962         puv[1][0] = orig_uv[1][0] * ibuf_x;
963         puv[1][1] = orig_uv[1][1] * ibuf_y;
964
965         puv[2][0] = orig_uv[2][0] * ibuf_x;
966         puv[2][1] = orig_uv[2][1] * ibuf_y;
967
968         if (is_quad) {
969                 puv[3][0] = orig_uv[3][0] * ibuf_x;
970                 puv[3][1] = orig_uv[3][1] * ibuf_y;
971         }
972
973         /* face edge directions */
974         sub_v2_v2v2(dir1, puv[1], puv[0]);
975         sub_v2_v2v2(dir2, puv[2], puv[1]);
976         normalize_v2(dir1);
977         normalize_v2(dir2);
978
979         if (is_quad) {
980                 sub_v2_v2v2(dir3, puv[3], puv[2]);
981                 sub_v2_v2v2(dir4, puv[0], puv[3]);
982                 normalize_v2(dir3);
983                 normalize_v2(dir4);
984         }
985         else {
986                 sub_v2_v2v2(dir3, puv[0], puv[2]);
987                 normalize_v2(dir3);
988         }
989
990         /* TODO - angle_normalized_v2v2(...) * (M_PI/180.0f)
991          * This is incorrect. Its already given radians but without it wont work.
992          * need to look into a fix - campbell */
993         if (is_quad) {
994                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir4, dir1) * ((float)M_PI / 180.0f));
995                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI / 180.0f));
996                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI / 180.0f));
997                 a4 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir4) * ((float)M_PI / 180.0f));
998         }
999         else {
1000                 a1 = shell_angle_to_dist(angle_normalized_v2v2(dir3, dir1) * ((float)M_PI / 180.0f));
1001                 a2 = shell_angle_to_dist(angle_normalized_v2v2(dir1, dir2) * ((float)M_PI / 180.0f));
1002                 a3 = shell_angle_to_dist(angle_normalized_v2v2(dir2, dir3) * ((float)M_PI / 180.0f));
1003         }
1004
1005         if (is_quad) {
1006                 sub_v2_v2v2(no1, dir4, dir1);
1007                 sub_v2_v2v2(no2, dir1, dir2);
1008                 sub_v2_v2v2(no3, dir2, dir3);
1009                 sub_v2_v2v2(no4, dir3, dir4);
1010                 normalize_v2(no1);
1011                 normalize_v2(no2);
1012                 normalize_v2(no3);
1013                 normalize_v2(no4);
1014                 mul_v2_fl(no1, a1 * scaler);
1015                 mul_v2_fl(no2, a2 * scaler);
1016                 mul_v2_fl(no3, a3 * scaler);
1017                 mul_v2_fl(no4, a4 * scaler);
1018                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1019                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1020                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1021                 add_v2_v2v2(outset_uv[3], puv[3], no4);
1022                 mul_v2_v2(outset_uv[0], ibuf_inv);
1023                 mul_v2_v2(outset_uv[1], ibuf_inv);
1024                 mul_v2_v2(outset_uv[2], ibuf_inv);
1025                 mul_v2_v2(outset_uv[3], ibuf_inv);
1026         }
1027         else {
1028                 sub_v2_v2v2(no1, dir3, dir1);
1029                 sub_v2_v2v2(no2, dir1, dir2);
1030                 sub_v2_v2v2(no3, dir2, dir3);
1031                 normalize_v2(no1);
1032                 normalize_v2(no2);
1033                 normalize_v2(no3);
1034                 mul_v2_fl(no1, a1 * scaler);
1035                 mul_v2_fl(no2, a2 * scaler);
1036                 mul_v2_fl(no3, a3 * scaler);
1037                 add_v2_v2v2(outset_uv[0], puv[0], no1);
1038                 add_v2_v2v2(outset_uv[1], puv[1], no2);
1039                 add_v2_v2v2(outset_uv[2], puv[2], no3);
1040
1041                 mul_v2_v2(outset_uv[0], ibuf_inv);
1042                 mul_v2_v2(outset_uv[1], ibuf_inv);
1043                 mul_v2_v2(outset_uv[2], ibuf_inv);
1044         }
1045 }
1046
1047 /*
1048  * Be tricky with flags, first 4 bits are PROJ_FACE_SEAM1 to 4, last 4 bits are PROJ_FACE_NOSEAM1 to 4
1049  * 1<<i - where i is (0-3)
1050  *
1051  * If we're multithreadng, make sure threads are locked when this is called
1052  */
1053 static void project_face_seams_init(const ProjPaintState *ps, const int face_index, const int is_quad)
1054 {
1055         int other_face, other_fidx; /* vars for the other face, we also set its flag */
1056         int fidx1 = is_quad ? 3 : 2;
1057         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 */
1058
1059         do {
1060                 if ((ps->faceSeamFlags[face_index] & (1 << fidx1 | 16 << fidx1)) == 0) {
1061                         if (check_seam(ps, face_index, fidx1, fidx2, &other_face, &other_fidx)) {
1062                                 ps->faceSeamFlags[face_index] |= 1 << fidx1;
1063                                 if (other_face != -1)
1064                                         ps->faceSeamFlags[other_face] |= 1 << other_fidx;
1065                         }
1066                         else {
1067                                 ps->faceSeamFlags[face_index] |= 16 << fidx1;
1068                                 if (other_face != -1)
1069                                         ps->faceSeamFlags[other_face] |= 16 << other_fidx;  /* second 4 bits for disabled */
1070                         }
1071                 }
1072
1073                 fidx2 = fidx1;
1074         } while (fidx1--);
1075 }
1076 #endif // PROJ_DEBUG_NOSEAMBLEED
1077
1078
1079 /* Converts a UV location to a 3D screenspace location
1080  * Takes a 'uv' and 3 UV coords, and sets the values of pixelScreenCo
1081  *
1082  * This is used for finding a pixels location in screenspace for painting */
1083 static void screen_px_from_ortho(
1084         float uv[2],
1085         float v1co[3], float v2co[3], float v3co[3],  /* Screenspace coords */
1086         float uv1co[2], float uv2co[2], float uv3co[2],
1087         float pixelScreenCo[4],
1088         float w[3])
1089 {
1090         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1091         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1092 }
1093
1094 /* same as screen_px_from_ortho except we need to take into account
1095  * the perspective W coord for each vert */
1096 static void screen_px_from_persp(
1097         float uv[2],
1098         float v1co[4], float v2co[4], float v3co[4],  /* screenspace coords */
1099         float uv1co[2], float uv2co[2], float uv3co[2],
1100         float pixelScreenCo[4],
1101         float w[3])
1102 {
1103
1104         float wtot_inv, wtot;
1105         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1106
1107         /* re-weight from the 4th coord of each screen vert */
1108         w[0] *= v1co[3];
1109         w[1] *= v2co[3];
1110         w[2] *= v3co[3];
1111
1112         wtot = w[0] + w[1] + w[2];
1113
1114         if (wtot > 0.0f) {
1115                 wtot_inv = 1.0f / wtot;
1116                 w[0] *= wtot_inv;
1117                 w[1] *= wtot_inv;
1118                 w[2] *= wtot_inv;
1119         }
1120         else {
1121                 w[0] = w[1] = w[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1122         }
1123         /* done re-weighting */
1124
1125         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w);
1126 }
1127
1128
1129 /* same as screen_px_from_persp except we return ortho weights back to the caller.
1130  * These weights will be used to determine correct interpolation of uvs in cloned uv layer */
1131 static void screen_px_from_persp_ortho_weights(
1132         float uv[2],
1133         float v1co[4], float v2co[4], float v3co[4],  /* screenspace coords */
1134         float uv1co[2], float uv2co[2], float uv3co[2],
1135         float pixelScreenCo[4],
1136         float w[3])
1137 {
1138         float w_int[3];
1139         float wtot_inv, wtot;
1140         barycentric_weights_v2(uv1co, uv2co, uv3co, uv, w);
1141
1142         /* re-weight from the 4th coord of each screen vert */
1143         w_int[0] = w[0] * v1co[3];
1144         w_int[1] = w[1] * v2co[3];
1145         w_int[2] = w[2] * v3co[3];
1146
1147         wtot = w_int[0] + w_int[1] + w_int[2];
1148
1149         if (wtot > 0.0f) {
1150                 wtot_inv = 1.0f / wtot;
1151                 w_int[0] *= wtot_inv;
1152                 w_int[1] *= wtot_inv;
1153                 w_int[2] *= wtot_inv;
1154         }
1155         else {
1156                 w[0] = w[1] = w[2] =
1157                 w_int[0] = w_int[1] = w_int[2] = 1.0f / 3.0f;  /* dummy values for zero area face */
1158         }
1159         /* done re-weighting */
1160
1161         /* do interpolation based on projected weight */
1162         interp_v3_v3v3v3(pixelScreenCo, v1co, v2co, v3co, w_int);
1163 }
1164
1165
1166 static void project_face_pixel(const MTFace *tf_other, ImBuf *ibuf_other, const float w[3],
1167                                int side, unsigned char rgba_ub[4], float rgba_f[4])
1168 {
1169         float *uvCo1, *uvCo2, *uvCo3;
1170         float uv_other[2], x, y;
1171
1172         uvCo1 =  (float *)tf_other->uv[0];
1173         if (side == 1) {
1174                 uvCo2 =  (float *)tf_other->uv[2];
1175                 uvCo3 =  (float *)tf_other->uv[3];
1176         }
1177         else {
1178                 uvCo2 =  (float *)tf_other->uv[1];
1179                 uvCo3 =  (float *)tf_other->uv[2];
1180         }
1181
1182         interp_v2_v2v2v2(uv_other, uvCo1, uvCo2, uvCo3, (float *)w);
1183
1184         /* use */
1185         uvco_to_wrapped_pxco(uv_other, ibuf_other->x, ibuf_other->y, &x, &y);
1186
1187
1188         if (ibuf_other->rect_float) { /* from float to float */
1189                 bilinear_interpolation_color_wrap(ibuf_other, NULL, rgba_f, x, y);
1190         }
1191         else { /* from char to float */
1192                 bilinear_interpolation_color_wrap(ibuf_other, rgba_ub, NULL, x, y);
1193         }
1194
1195 }
1196
1197 /* run this outside project_paint_uvpixel_init since pixels with mask 0 don't need init */
1198 static float project_paint_uvpixel_mask(
1199         const ProjPaintState *ps,
1200         const int face_index,
1201         const int side,
1202         const float w[3])
1203 {
1204         float mask;
1205
1206         /* Image Mask */
1207         if (ps->do_layer_stencil) {
1208                 /* another UV maps image is masking this one's */
1209                 ImBuf *ibuf_other;
1210                 Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_stencil, face_index);
1211                 const MTFace *tf_other = ps->dm_mtface_stencil + face_index;
1212
1213                 if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1214                         /* BKE_image_acquire_ibuf - TODO - this may be slow */
1215                         unsigned char rgba_ub[4];
1216                         float rgba_f[4];
1217
1218                         project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, rgba_f);
1219
1220                         if (ibuf_other->rect_float) { /* from float to float */
1221                                 mask = ((rgba_f[0] + rgba_f[1] + rgba_f[2]) * (1.0f / 3.0f)) * rgba_f[3];
1222                         }
1223                         else { /* from char to float */
1224                                 mask = ((rgba_ub[0] + rgba_ub[1] + rgba_ub[2]) * (1.0f / (255.0f * 3.0f))) * (rgba_ub[3] * (1.0f / 255.0f));
1225                         }
1226
1227                         BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1228
1229                         if (!ps->do_layer_stencil_inv) /* matching the gimps layer mask black/white rules, white==full opacity */
1230                                 mask = (1.0f - mask);
1231
1232                         if (mask == 0.0f) {
1233                                 return 0.0f;
1234                         }
1235                 }
1236                 else {
1237                         return 0.0f;
1238                 }
1239         }
1240         else {
1241                 mask = 1.0f;
1242         }
1243
1244         /* calculate mask */
1245         if (ps->do_mask_normal) {
1246                 MFace *mf = &ps->dm_mface[face_index];
1247                 float no[3], angle;
1248                 if (mf->flag & ME_SMOOTH) {
1249                         short *no1, *no2, *no3;
1250                         no1 = ps->dm_mvert[mf->v1].no;
1251                         if (side == 1) {
1252                                 no2 = ps->dm_mvert[mf->v3].no;
1253                                 no3 = ps->dm_mvert[mf->v4].no;
1254                         }
1255                         else {
1256                                 no2 = ps->dm_mvert[mf->v2].no;
1257                                 no3 = ps->dm_mvert[mf->v3].no;
1258                         }
1259
1260                         no[0] = w[0] * no1[0] + w[1] * no2[0] + w[2] * no3[0];
1261                         no[1] = w[0] * no1[1] + w[1] * no2[1] + w[2] * no3[1];
1262                         no[2] = w[0] * no1[2] + w[1] * no2[2] + w[2] * no3[2];
1263                         normalize_v3(no);
1264                 }
1265                 else {
1266                         /* incase the */
1267 #if 1
1268                         /* normalizing per pixel isn't optimal, we could cache or check ps->*/
1269                         if (mf->v4)
1270                                 normal_quad_v3(no,
1271                                                ps->dm_mvert[mf->v1].co,
1272                                                ps->dm_mvert[mf->v2].co,
1273                                                ps->dm_mvert[mf->v3].co,
1274                                                ps->dm_mvert[mf->v4].co);
1275                         else
1276                                 normal_tri_v3(no,
1277                                               ps->dm_mvert[mf->v1].co,
1278                                               ps->dm_mvert[mf->v2].co,
1279                                               ps->dm_mvert[mf->v3].co);
1280 #else
1281                         /* don't use because some modifiers dont have normal data (subsurf for eg) */
1282                         copy_v3_v3(no, (float *)ps->dm->getTessFaceData(ps->dm, face_index, CD_NORMAL));
1283 #endif
1284                 }
1285
1286                 /* now we can use the normal as a mask */
1287                 if (ps->is_ortho) {
1288                         angle = angle_normalized_v3v3((float *)ps->viewDir, no);
1289                 }
1290                 else {
1291                         /* Annoying but for the perspective view we need to get the pixels location in 3D space :/ */
1292                         float viewDirPersp[3];
1293                         float *co1, *co2, *co3;
1294                         co1 = ps->dm_mvert[mf->v1].co;
1295                         if (side == 1) {
1296                                 co2 = ps->dm_mvert[mf->v3].co;
1297                                 co3 = ps->dm_mvert[mf->v4].co;
1298                         }
1299                         else {
1300                                 co2 = ps->dm_mvert[mf->v2].co;
1301                                 co3 = ps->dm_mvert[mf->v3].co;
1302                         }
1303
1304                         /* Get the direction from the viewPoint to the pixel and normalize */
1305                         viewDirPersp[0] = (ps->viewPos[0] - (w[0] * co1[0] + w[1] * co2[0] + w[2] * co3[0]));
1306                         viewDirPersp[1] = (ps->viewPos[1] - (w[0] * co1[1] + w[1] * co2[1] + w[2] * co3[1]));
1307                         viewDirPersp[2] = (ps->viewPos[2] - (w[0] * co1[2] + w[1] * co2[2] + w[2] * co3[2]));
1308                         normalize_v3(viewDirPersp);
1309
1310                         angle = angle_normalized_v3v3(viewDirPersp, no);
1311                 }
1312
1313                 if (angle >= ps->normal_angle) {
1314                         return 0.0f; /* outsize the normal limit*/
1315                 }
1316                 else if (angle > ps->normal_angle_inner) {
1317                         mask *= (ps->normal_angle - angle) / ps->normal_angle_range;
1318                 } /* otherwise no mask normal is needed, were within the limit */
1319         }
1320
1321         /* This only works when the opacity dosnt change while painting, stylus pressure messes with this
1322          * so don't use it. */
1323         // if (ps->is_airbrush == 0) mask *= BKE_brush_alpha_get(ps->brush);
1324
1325         return mask;
1326 }
1327
1328 static int project_paint_pixel_sizeof(const short tool)
1329 {
1330         if ((tool == PAINT_TOOL_CLONE) || (tool == PAINT_TOOL_SMEAR)) {
1331                 return sizeof(ProjPixelClone);
1332         }
1333         else {
1334                 return sizeof(ProjPixel);
1335         }
1336 }
1337
1338
1339 /* run this function when we know a bucket's, face's pixel can be initialized,
1340  * return the ProjPixel which is added to 'ps->bucketRect[bucket_index]' */
1341 static ProjPixel *project_paint_uvpixel_init(
1342         const ProjPaintState *ps,
1343         MemArena *arena,
1344         const ImBuf *ibuf,
1345         int x_px, int y_px,
1346         const float mask,
1347         const int face_index,
1348         const int image_index,
1349         const float pixelScreenCo[4],
1350         const float world_spaceCo[3],
1351         const int side,
1352         const float w[3])
1353 {
1354         ProjPixel *projPixel;
1355
1356         /* wrap pixel location */
1357
1358         x_px = mod_i(x_px, ibuf->x);
1359         y_px = mod_i(y_px, ibuf->y);
1360
1361         BLI_assert(ps->pixel_sizeof == project_paint_pixel_sizeof(ps->tool));
1362         projPixel = (ProjPixel *)BLI_memarena_alloc(arena, ps->pixel_sizeof);
1363         //memset(projPixel, 0, size);
1364
1365         if (ibuf->rect_float) {
1366                 projPixel->pixel.f_pt = ibuf->rect_float + ((x_px + y_px * ibuf->x) * 4);
1367                 projPixel->origColor.f[0] = projPixel->pixel.f_pt[0];
1368                 projPixel->origColor.f[1] = projPixel->pixel.f_pt[1];
1369                 projPixel->origColor.f[2] = projPixel->pixel.f_pt[2];
1370                 projPixel->origColor.f[3] = projPixel->pixel.f_pt[3];
1371                 zero_v4(projPixel->newColor.f);
1372         }
1373         else {
1374                 projPixel->pixel.ch_pt = ((unsigned char *)ibuf->rect + ((x_px + y_px * ibuf->x) * 4));
1375                 projPixel->origColor.uint = *projPixel->pixel.uint_pt;
1376                 projPixel->newColor.uint = 0;
1377         }
1378
1379         /* screenspace unclamped, we could keep its z and w values but don't need them at the moment */
1380         if (ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D) {
1381                 copy_v3_v3(projPixel->worldCoSS, world_spaceCo);
1382         }
1383
1384         copy_v2_v2(projPixel->projCoSS, pixelScreenCo);
1385
1386         projPixel->x_px = x_px;
1387         projPixel->y_px = y_px;
1388
1389         projPixel->mask = (unsigned short)(mask * 65535);
1390         projPixel->mask_accum = 0;
1391
1392         /* which bounding box cell are we in?, needed for undo */
1393         projPixel->bb_cell_index = ((int)(((float)x_px / (float)ibuf->x) * PROJ_BOUNDBOX_DIV)) +
1394                                    ((int)(((float)y_px / (float)ibuf->y) * PROJ_BOUNDBOX_DIV)) * PROJ_BOUNDBOX_DIV;
1395
1396         /* done with view3d_project_float inline */
1397         if (ps->tool == PAINT_TOOL_CLONE) {
1398                 if (ps->dm_mtface_clone) {
1399                         ImBuf *ibuf_other;
1400                         Image *other_tpage = project_paint_face_image(ps, ps->dm_mtface_clone, face_index);
1401                         const MTFace *tf_other = ps->dm_mtface_clone + face_index;
1402
1403                         if (other_tpage && (ibuf_other = BKE_image_acquire_ibuf(other_tpage, NULL, NULL))) {
1404                                 /* BKE_image_acquire_ibuf - TODO - this may be slow */
1405
1406                                 if (ibuf->rect_float) {
1407                                         if (ibuf_other->rect_float) { /* from float to float */
1408                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, ((ProjPixelClone *)projPixel)->clonepx.f);
1409                                         }
1410                                         else { /* from char to float */
1411                                                 unsigned char rgba_ub[4];
1412                                                 float rgba[4];
1413                                                 project_face_pixel(tf_other, ibuf_other, w, side, rgba_ub, NULL);
1414                                                 srgb_to_linearrgb_uchar4(rgba, rgba_ub);
1415                                                 straight_to_premul_v4_v4(((ProjPixelClone *)projPixel)->clonepx.f, rgba);
1416                                         }
1417                                 }
1418                                 else {
1419                                         if (ibuf_other->rect_float) { /* float to char */
1420                                                 float rgba[4];
1421                                                 project_face_pixel(tf_other, ibuf_other, w, side, NULL, rgba);
1422                                                 premul_to_straight_v4(rgba);
1423                                                 linearrgb_to_srgb_uchar3(((ProjPixelClone *)projPixel)->clonepx.ch, rgba);
1424                                         }
1425                                         else { /* char to char */
1426                                                 project_face_pixel(tf_other, ibuf_other, w, side, ((ProjPixelClone *)projPixel)->clonepx.ch, NULL);
1427                                         }
1428                                 }
1429
1430                                 BKE_image_release_ibuf(other_tpage, ibuf_other, NULL);
1431                         }
1432                         else {
1433                                 if (ibuf->rect_float) {
1434                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0;
1435                                 }
1436                                 else {
1437                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0;
1438                                 }
1439                         }
1440
1441                 }
1442                 else {
1443                         float co[2];
1444                         sub_v2_v2v2(co, projPixel->projCoSS, (float *)ps->cloneOffset);
1445
1446                         /* no need to initialize the bucket, we're only checking buckets faces and for this
1447                          * the faces are already initialized in project_paint_delayed_face_init(...) */
1448                         if (ibuf->rect_float) {
1449                                 if (!project_paint_PickColor(ps, co, ((ProjPixelClone *)projPixel)->clonepx.f, NULL, 1)) {
1450                                         ((ProjPixelClone *)projPixel)->clonepx.f[3] = 0; /* zero alpha - ignore */
1451                                 }
1452                         }
1453                         else {
1454                                 if (!project_paint_PickColor(ps, co, NULL, ((ProjPixelClone *)projPixel)->clonepx.ch, 1)) {
1455                                         ((ProjPixelClone *)projPixel)->clonepx.ch[3] = 0; /* zero alpha - ignore */
1456                                 }
1457                         }
1458                 }
1459         }
1460
1461 #ifdef PROJ_DEBUG_PAINT
1462         if (ibuf->rect_float) projPixel->pixel.f_pt[0] = 0;
1463         else                  projPixel->pixel.ch_pt[0] = 0;
1464 #endif
1465         projPixel->image_index = image_index;
1466
1467         return projPixel;
1468 }
1469
1470 static bool line_clip_rect2f(
1471         rctf *rect,
1472         const float l1[2], const float l2[2],
1473         float l1_clip[2], float l2_clip[2])
1474 {
1475         /* first account for horizontal, then vertical lines */
1476         /* horiz */
1477         if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) {
1478                 /* is the line out of range on its Y axis? */
1479                 if (l1[1] < rect->ymin || l1[1] > rect->ymax) {
1480                         return 0;
1481                 }
1482                 /* line is out of range on its X axis */
1483                 if ((l1[0] < rect->xmin && l2[0] < rect->xmin) || (l1[0] > rect->xmax && l2[0] > rect->xmax)) {
1484                         return 0;
1485                 }
1486
1487
1488                 if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1489                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1490                                 copy_v2_v2(l1_clip, l1);
1491                                 copy_v2_v2(l2_clip, l2);
1492                                 return 1;
1493                         }
1494                         else {
1495                                 return 0;
1496                         }
1497                 }
1498
1499                 copy_v2_v2(l1_clip, l1);
1500                 copy_v2_v2(l2_clip, l2);
1501                 CLAMP(l1_clip[0], rect->xmin, rect->xmax);
1502                 CLAMP(l2_clip[0], rect->xmin, rect->xmax);
1503                 return 1;
1504         }
1505         else if (fabsf(l1[0] - l2[0]) < PROJ_GEOM_TOLERANCE) {
1506                 /* is the line out of range on its X axis? */
1507                 if (l1[0] < rect->xmin || l1[0] > rect->xmax) {
1508                         return 0;
1509                 }
1510
1511                 /* line is out of range on its Y axis */
1512                 if ((l1[1] < rect->ymin && l2[1] < rect->ymin) || (l1[1] > rect->ymax && l2[1] > rect->ymax)) {
1513                         return 0;
1514                 }
1515
1516                 if (fabsf(l1[1] - l2[1]) < PROJ_GEOM_TOLERANCE) { /* this is a single point  (or close to)*/
1517                         if (BLI_rctf_isect_pt_v(rect, l1)) {
1518                                 copy_v2_v2(l1_clip, l1);
1519                                 copy_v2_v2(l2_clip, l2);
1520                                 return 1;
1521                         }
1522                         else {
1523                                 return 0;
1524                         }
1525                 }
1526
1527                 copy_v2_v2(l1_clip, l1);
1528                 copy_v2_v2(l2_clip, l2);
1529                 CLAMP(l1_clip[1], rect->ymin, rect->ymax);
1530                 CLAMP(l2_clip[1], rect->ymin, rect->ymax);
1531                 return 1;
1532         }
1533         else {
1534                 float isect;
1535                 short ok1 = 0;
1536                 short ok2 = 0;
1537
1538                 /* Done with vertical lines */
1539
1540                 /* are either of the points inside the rectangle ? */
1541                 if (BLI_rctf_isect_pt_v(rect, l1)) {
1542                         copy_v2_v2(l1_clip, l1);
1543                         ok1 = 1;
1544                 }
1545
1546                 if (BLI_rctf_isect_pt_v(rect, l2)) {
1547                         copy_v2_v2(l2_clip, l2);
1548                         ok2 = 1;
1549                 }
1550
1551                 /* line inside rect */
1552                 if (ok1 && ok2) return 1;
1553
1554                 /* top/bottom */
1555                 if (line_isect_y(l1, l2, rect->ymin, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1556                         if (l1[1] < l2[1]) { /* line 1 is outside */
1557                                 l1_clip[0] = isect;
1558                                 l1_clip[1] = rect->ymin;
1559                                 ok1 = 1;
1560                         }
1561                         else {
1562                                 l2_clip[0] = isect;
1563                                 l2_clip[1] = rect->ymin;
1564                                 ok2 = 2;
1565                         }
1566                 }
1567
1568                 if (ok1 && ok2) return 1;
1569
1570                 if (line_isect_y(l1, l2, rect->ymax, &isect) && (isect >= rect->xmin) && (isect <= rect->xmax)) {
1571                         if (l1[1] > l2[1]) { /* line 1 is outside */
1572                                 l1_clip[0] = isect;
1573                                 l1_clip[1] = rect->ymax;
1574                                 ok1 = 1;
1575                         }
1576                         else {
1577                                 l2_clip[0] = isect;
1578                                 l2_clip[1] = rect->ymax;
1579                                 ok2 = 2;
1580                         }
1581                 }
1582
1583                 if (ok1 && ok2) return 1;
1584
1585                 /* left/right */
1586                 if (line_isect_x(l1, l2, rect->xmin, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1587                         if (l1[0] < l2[0]) { /* line 1 is outside */
1588                                 l1_clip[0] = rect->xmin;
1589                                 l1_clip[1] = isect;
1590                                 ok1 = 1;
1591                         }
1592                         else {
1593                                 l2_clip[0] = rect->xmin;
1594                                 l2_clip[1] = isect;
1595                                 ok2 = 2;
1596                         }
1597                 }
1598
1599                 if (ok1 && ok2) return 1;
1600
1601                 if (line_isect_x(l1, l2, rect->xmax, &isect) && (isect >= rect->ymin) && (isect <= rect->ymax)) {
1602                         if (l1[0] > l2[0]) { /* line 1 is outside */
1603                                 l1_clip[0] = rect->xmax;
1604                                 l1_clip[1] = isect;
1605                                 ok1 = 1;
1606                         }
1607                         else {
1608                                 l2_clip[0] = rect->xmax;
1609                                 l2_clip[1] = isect;
1610                                 ok2 = 2;
1611                         }
1612                 }
1613
1614                 if (ok1 && ok2) {
1615                         return 1;
1616                 }
1617                 else {
1618                         return 0;
1619                 }
1620         }
1621 }
1622
1623
1624
1625 /* scale the quad & tri about its center
1626  * scaling by PROJ_FACE_SCALE_SEAM (0.99x) is used for getting fake UV pixel coords that are on the
1627  * edge of the face but slightly inside it occlusion tests don't return hits on adjacent faces */
1628 #ifndef PROJ_DEBUG_NOSEAMBLEED
1629 static void scale_quad(float insetCos[4][3], float *origCos[4], const float inset)
1630 {
1631         float cent[3];
1632         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0] + origCos[3][0]) * (1.0f / 4.0f);
1633         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1] + origCos[3][1]) * (1.0f / 4.0f);
1634         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2] + origCos[3][2]) * (1.0f / 4.0f);
1635
1636         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1637         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1638         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1639         sub_v3_v3v3(insetCos[3], origCos[3], cent);
1640
1641         mul_v3_fl(insetCos[0], inset);
1642         mul_v3_fl(insetCos[1], inset);
1643         mul_v3_fl(insetCos[2], inset);
1644         mul_v3_fl(insetCos[3], inset);
1645
1646         add_v3_v3(insetCos[0], cent);
1647         add_v3_v3(insetCos[1], cent);
1648         add_v3_v3(insetCos[2], cent);
1649         add_v3_v3(insetCos[3], cent);
1650 }
1651
1652
1653 static void scale_tri(float insetCos[4][3], float *origCos[4], const float inset)
1654 {
1655         float cent[3];
1656         cent[0] = (origCos[0][0] + origCos[1][0] + origCos[2][0]) * (1.0f / 3.0f);
1657         cent[1] = (origCos[0][1] + origCos[1][1] + origCos[2][1]) * (1.0f / 3.0f);
1658         cent[2] = (origCos[0][2] + origCos[1][2] + origCos[2][2]) * (1.0f / 3.0f);
1659
1660         sub_v3_v3v3(insetCos[0], origCos[0], cent);
1661         sub_v3_v3v3(insetCos[1], origCos[1], cent);
1662         sub_v3_v3v3(insetCos[2], origCos[2], cent);
1663
1664         mul_v3_fl(insetCos[0], inset);
1665         mul_v3_fl(insetCos[1], inset);
1666         mul_v3_fl(insetCos[2], inset);
1667
1668         add_v3_v3(insetCos[0], cent);
1669         add_v3_v3(insetCos[1], cent);
1670         add_v3_v3(insetCos[2], cent);
1671 }
1672 #endif //PROJ_DEBUG_NOSEAMBLEED
1673
1674 static float len_squared_v2v2_alt(const float *v1, const float v2_1, const float v2_2)
1675 {
1676         float x, y;
1677
1678         x = v1[0] - v2_1;
1679         y = v1[1] - v2_2;
1680         return x * x + y * y;
1681 }
1682
1683 /* note, use a squared value so we can use len_squared_v2v2
1684  * be sure that you have done a bounds check first or this may fail */
1685 /* only give bucket_bounds as an arg because we need it elsewhere */
1686 static bool project_bucket_isect_circle(const float cent[2], const float radius_squared, rctf *bucket_bounds)
1687 {
1688
1689         /* Would normally to a simple intersection test, however we know the bounds of these 2 already intersect
1690          * so we only need to test if the center is inside the vertical or horizontal bounds on either axis,
1691          * this is even less work then an intersection test
1692          */
1693 #if 0
1694         if (BLI_rctf_isect_pt_v(bucket_bounds, cent))
1695                 return 1;
1696 #endif
1697
1698         if ((bucket_bounds->xmin <= cent[0] && bucket_bounds->xmax >= cent[0]) ||
1699             (bucket_bounds->ymin <= cent[1] && bucket_bounds->ymax >= cent[1]))
1700         {
1701                 return 1;
1702         }
1703
1704         /* out of bounds left */
1705         if (cent[0] < bucket_bounds->xmin) {
1706                 /* lower left out of radius test */
1707                 if (cent[1] < bucket_bounds->ymin) {
1708                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1709                 }
1710                 /* top left test */
1711                 else if (cent[1] > bucket_bounds->ymax) {
1712                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmin, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1713                 }
1714         }
1715         else if (cent[0] > bucket_bounds->xmax) {
1716                 /* lower right out of radius test */
1717                 if (cent[1] < bucket_bounds->ymin) {
1718                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymin) < radius_squared) ? 1 : 0;
1719                 }
1720                 /* top right test */
1721                 else if (cent[1] > bucket_bounds->ymax) {
1722                         return (len_squared_v2v2_alt(cent, bucket_bounds->xmax, bucket_bounds->ymax) < radius_squared) ? 1 : 0;
1723                 }
1724         }
1725
1726         return 0;
1727 }
1728
1729
1730
1731 /* Note for rect_to_uvspace_ortho() and rect_to_uvspace_persp()
1732  * in ortho view this function gives good results when bucket_bounds are outside the triangle
1733  * however in some cases, perspective view will mess up with faces that have minimal screenspace area
1734  * (viewed from the side)
1735  *
1736  * for this reason its not reliable in this case so we'll use the Simple Barycentric'
1737  * funcs that only account for points inside the triangle.
1738  * however switching back to this for ortho is always an option */
1739
1740 static void rect_to_uvspace_ortho(
1741         rctf *bucket_bounds,
1742         float *v1coSS, float *v2coSS, float *v3coSS,
1743         float *uv1co, float *uv2co, float *uv3co,
1744         float bucket_bounds_uv[4][2],
1745         const int flip)
1746 {
1747         float uv[2];
1748         float w[3];
1749
1750         /* get the UV space bounding box */
1751         uv[0] = bucket_bounds->xmax;
1752         uv[1] = bucket_bounds->ymin;
1753         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1754         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1755
1756         //uv[0] = bucket_bounds->xmax; // set above
1757         uv[1] = bucket_bounds->ymax;
1758         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1759         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1760
1761         uv[0] = bucket_bounds->xmin;
1762         //uv[1] = bucket_bounds->ymax; // set above
1763         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1764         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1765
1766         //uv[0] = bucket_bounds->xmin; // set above
1767         uv[1] = bucket_bounds->ymin;
1768         barycentric_weights_v2(v1coSS, v2coSS, v3coSS, uv, w);
1769         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1770 }
1771
1772 /* same as above but use barycentric_weights_v2_persp */
1773 static void rect_to_uvspace_persp(
1774         rctf *bucket_bounds,
1775         float *v1coSS, float *v2coSS, float *v3coSS,
1776         float *uv1co, float *uv2co, float *uv3co,
1777         float bucket_bounds_uv[4][2],
1778         const int flip
1779         )
1780 {
1781         float uv[2];
1782         float w[3];
1783
1784         /* get the UV space bounding box */
1785         uv[0] = bucket_bounds->xmax;
1786         uv[1] = bucket_bounds->ymin;
1787         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1788         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 3 : 0], uv1co, uv2co, uv3co, w);
1789
1790         //uv[0] = bucket_bounds->xmax; // set above
1791         uv[1] = bucket_bounds->ymax;
1792         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1793         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 2 : 1], uv1co, uv2co, uv3co, w);
1794
1795         uv[0] = bucket_bounds->xmin;
1796         //uv[1] = bucket_bounds->ymax; // set above
1797         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1798         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 1 : 2], uv1co, uv2co, uv3co, w);
1799
1800         //uv[0] = bucket_bounds->xmin; // set above
1801         uv[1] = bucket_bounds->ymin;
1802         barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, uv, w);
1803         interp_v2_v2v2v2(bucket_bounds_uv[flip ? 0 : 3], uv1co, uv2co, uv3co, w);
1804 }
1805
1806 /* This works as we need it to but we can save a few steps and not use it */
1807
1808 #if 0
1809 static float angle_2d_clockwise(const float p1[2], const float p2[2], const float p3[2])
1810 {
1811         float v1[2], v2[2];
1812
1813         v1[0] = p1[0] - p2[0];    v1[1] = p1[1] - p2[1];
1814         v2[0] = p3[0] - p2[0];    v2[1] = p3[1] - p2[1];
1815
1816         return -atan2(v1[0] * v2[1] - v1[1] * v2[0], v1[0] * v2[0] + v1[1] * v2[1]);
1817 }
1818 #endif
1819
1820 #define ISECT_1 (1)
1821 #define ISECT_2 (1 << 1)
1822 #define ISECT_3 (1 << 2)
1823 #define ISECT_4 (1 << 3)
1824 #define ISECT_ALL3 ((1 << 3) - 1)
1825 #define ISECT_ALL4 ((1 << 4) - 1)
1826
1827 /* limit must be a fraction over 1.0f */
1828 static bool IsectPT2Df_limit(float pt[2], float v1[2], float v2[2], float v3[2], float limit)
1829 {
1830         return ((area_tri_v2(pt, v1, v2) +
1831                  area_tri_v2(pt, v2, v3) +
1832                  area_tri_v2(pt, v3, v1)) / (area_tri_v2(v1, v2, v3))) < limit;
1833 }
1834
1835 /* Clip the face by a bucket and set the uv-space bucket_bounds_uv
1836  * so we have the clipped UV's to do pixel intersection tests with
1837  * */
1838 static int float_z_sort_flip(const void *p1, const void *p2)
1839 {
1840         return (((float *)p1)[2] < ((float *)p2)[2] ? 1 : -1);
1841 }
1842
1843 static int float_z_sort(const void *p1, const void *p2)
1844 {
1845         return (((float *)p1)[2] < ((float *)p2)[2] ? -1 : 1);
1846 }
1847
1848 static void project_bucket_clip_face(
1849         const int is_ortho,
1850         rctf *bucket_bounds,
1851         float *v1coSS, float *v2coSS, float *v3coSS,
1852         float *uv1co, float *uv2co, float *uv3co,
1853         float bucket_bounds_uv[8][2],
1854         int *tot)
1855 {
1856         int inside_bucket_flag = 0;
1857         int inside_face_flag = 0;
1858         const int flip = ((line_point_side_v2(v1coSS, v2coSS, v3coSS) > 0.0f) != (line_point_side_v2(uv1co, uv2co, uv3co) > 0.0f));
1859
1860         float bucket_bounds_ss[4][2];
1861
1862         /* get the UV space bounding box */
1863         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v1coSS);
1864         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v2coSS) << 1;
1865         inside_bucket_flag |= BLI_rctf_isect_pt_v(bucket_bounds, v3coSS) << 2;
1866
1867         if (inside_bucket_flag == ISECT_ALL3) {
1868                 /* all screenspace points are inside the bucket bounding box, this means we don't need to clip and can simply return the UVs */
1869                 if (flip) { /* facing the back? */
1870                         copy_v2_v2(bucket_bounds_uv[0], uv3co);
1871                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1872                         copy_v2_v2(bucket_bounds_uv[2], uv1co);
1873                 }
1874                 else {
1875                         copy_v2_v2(bucket_bounds_uv[0], uv1co);
1876                         copy_v2_v2(bucket_bounds_uv[1], uv2co);
1877                         copy_v2_v2(bucket_bounds_uv[2], uv3co);
1878                 }
1879
1880                 *tot = 3;
1881                 return;
1882         }
1883
1884         /* get the UV space bounding box */
1885         /* use IsectPT2Df_limit here so we catch points are are touching the tri edge (or a small fraction over) */
1886         bucket_bounds_ss[0][0] = bucket_bounds->xmax;
1887         bucket_bounds_ss[0][1] = bucket_bounds->ymin;
1888         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[0], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_1 : 0);
1889
1890         bucket_bounds_ss[1][0] = bucket_bounds->xmax;
1891         bucket_bounds_ss[1][1] = bucket_bounds->ymax;
1892         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[1], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_2 : 0);
1893
1894         bucket_bounds_ss[2][0] = bucket_bounds->xmin;
1895         bucket_bounds_ss[2][1] = bucket_bounds->ymax;
1896         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[2], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_3 : 0);
1897
1898         bucket_bounds_ss[3][0] = bucket_bounds->xmin;
1899         bucket_bounds_ss[3][1] = bucket_bounds->ymin;
1900         inside_face_flag |= (IsectPT2Df_limit(bucket_bounds_ss[3], v1coSS, v2coSS, v3coSS, 1 + PROJ_GEOM_TOLERANCE) ? ISECT_4 : 0);
1901
1902         if (inside_face_flag == ISECT_ALL4) {
1903                 /* bucket is totally inside the screenspace face, we can safely use weights */
1904
1905                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
1906                 else rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, bucket_bounds_uv, flip);
1907
1908                 *tot = 4;
1909                 return;
1910         }
1911         else {
1912                 /* The Complicated Case!
1913                  *
1914                  * The 2 cases above are where the face is inside the bucket or the bucket is inside the face.
1915                  *
1916                  * we need to make a convex polyline from the intersection between the screenspace face
1917                  * and the bucket bounds.
1918                  *
1919                  * There are a number of ways this could be done, currently it just collects all intersecting verts,
1920                  * and line intersections,  then sorts them clockwise, this is a lot easier then evaluating the geometry to
1921                  * do a correct clipping on both shapes. */
1922
1923
1924                 /* add a bunch of points, we know must make up the convex hull which is the clipped rect and triangle */
1925
1926
1927
1928                 /* Maximum possible 6 intersections when using a rectangle and triangle */
1929                 float isectVCosSS[8][3]; /* The 3rd float is used to store angle for qsort(), NOT as a Z location */
1930                 float v1_clipSS[2], v2_clipSS[2];
1931                 float w[3];
1932
1933                 /* calc center */
1934                 float cent[2] = {0.0f, 0.0f};
1935                 /*float up[2] = {0.0f, 1.0f};*/
1936                 int i;
1937                 short doubles;
1938
1939                 (*tot) = 0;
1940
1941                 if (inside_face_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[0]); (*tot)++; }
1942                 if (inside_face_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[1]); (*tot)++; }
1943                 if (inside_face_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[2]); (*tot)++; }
1944                 if (inside_face_flag & ISECT_4) { copy_v2_v2(isectVCosSS[*tot], bucket_bounds_ss[3]); (*tot)++; }
1945
1946                 if (inside_bucket_flag & ISECT_1) { copy_v2_v2(isectVCosSS[*tot], v1coSS); (*tot)++; }
1947                 if (inside_bucket_flag & ISECT_2) { copy_v2_v2(isectVCosSS[*tot], v2coSS); (*tot)++; }
1948                 if (inside_bucket_flag & ISECT_3) { copy_v2_v2(isectVCosSS[*tot], v3coSS); (*tot)++; }
1949
1950                 if ((inside_bucket_flag & (ISECT_1 | ISECT_2)) != (ISECT_1 | ISECT_2)) {
1951                         if (line_clip_rect2f(bucket_bounds, v1coSS, v2coSS, v1_clipSS, v2_clipSS)) {
1952                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
1953                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
1954                         }
1955                 }
1956
1957                 if ((inside_bucket_flag & (ISECT_2 | ISECT_3)) != (ISECT_2 | ISECT_3)) {
1958                         if (line_clip_rect2f(bucket_bounds, v2coSS, v3coSS, v1_clipSS, v2_clipSS)) {
1959                                 if ((inside_bucket_flag & ISECT_2) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
1960                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
1961                         }
1962                 }
1963
1964                 if ((inside_bucket_flag & (ISECT_3 | ISECT_1)) != (ISECT_3 | ISECT_1)) {
1965                         if (line_clip_rect2f(bucket_bounds, v3coSS, v1coSS, v1_clipSS, v2_clipSS)) {
1966                                 if ((inside_bucket_flag & ISECT_3) == 0) { copy_v2_v2(isectVCosSS[*tot], v1_clipSS); (*tot)++; }
1967                                 if ((inside_bucket_flag & ISECT_1) == 0) { copy_v2_v2(isectVCosSS[*tot], v2_clipSS); (*tot)++; }
1968                         }
1969                 }
1970
1971
1972                 if ((*tot) < 3) { /* no intersections to speak of */
1973                         *tot = 0;
1974                         return;
1975                 }
1976
1977                 /* now we have all points we need, collect their angles and sort them clockwise */
1978
1979                 for (i = 0; i < (*tot); i++) {
1980                         cent[0] += isectVCosSS[i][0];
1981                         cent[1] += isectVCosSS[i][1];
1982                 }
1983                 cent[0] = cent[0] / (float)(*tot);
1984                 cent[1] = cent[1] / (float)(*tot);
1985
1986
1987
1988                 /* Collect angles for every point around the center point */
1989
1990
1991 #if 0   /* uses a few more cycles then the above loop */
1992                 for (i = 0; i < (*tot); i++) {
1993                         isectVCosSS[i][2] = angle_2d_clockwise(up, cent, isectVCosSS[i]);
1994                 }
1995 #endif
1996
1997                 v1_clipSS[0] = cent[0]; /* Abuse this var for the loop below */
1998                 v1_clipSS[1] = cent[1] + 1.0f;
1999
2000                 for (i = 0; i < (*tot); i++) {
2001                         v2_clipSS[0] = isectVCosSS[i][0] - cent[0];
2002                         v2_clipSS[1] = isectVCosSS[i][1] - cent[1];
2003                         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]);
2004                 }
2005
2006                 if (flip) qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort_flip);
2007                 else      qsort(isectVCosSS, *tot, sizeof(float) * 3, float_z_sort);
2008
2009                 /* remove doubles */
2010                 /* first/last check */
2011                 if (fabsf(isectVCosSS[0][0] - isectVCosSS[(*tot) - 1][0]) < PROJ_PIXEL_TOLERANCE &&
2012                     fabsf(isectVCosSS[0][1] - isectVCosSS[(*tot) - 1][1]) < PROJ_PIXEL_TOLERANCE)
2013                 {
2014                         (*tot)--;
2015                 }
2016
2017                 /* its possible there is only a few left after remove doubles */
2018                 if ((*tot) < 3) {
2019                         // printf("removed too many doubles A\n");
2020                         *tot = 0;
2021                         return;
2022                 }
2023
2024                 doubles = TRUE;
2025                 while (doubles == TRUE) {
2026                         doubles = FALSE;
2027                         for (i = 1; i < (*tot); i++) {
2028                                 if (fabsf(isectVCosSS[i - 1][0] - isectVCosSS[i][0]) < PROJ_PIXEL_TOLERANCE &&
2029                                     fabsf(isectVCosSS[i - 1][1] - isectVCosSS[i][1]) < PROJ_PIXEL_TOLERANCE)
2030                                 {
2031                                         int j;
2032                                         for (j = i + 1; j < (*tot); j++) {
2033                                                 isectVCosSS[j - 1][0] = isectVCosSS[j][0];
2034                                                 isectVCosSS[j - 1][1] = isectVCosSS[j][1];
2035                                         }
2036                                         doubles = TRUE; /* keep looking for more doubles */
2037                                         (*tot)--;
2038                                 }
2039                         }
2040                 }
2041
2042                 /* its possible there is only a few left after remove doubles */
2043                 if ((*tot) < 3) {
2044                         // printf("removed too many doubles B\n");
2045                         *tot = 0;
2046                         return;
2047                 }
2048
2049
2050                 if (is_ortho) {
2051                         for (i = 0; i < (*tot); i++) {
2052                                 barycentric_weights_v2(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2053                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2054                         }
2055                 }
2056                 else {
2057                         for (i = 0; i < (*tot); i++) {
2058                                 barycentric_weights_v2_persp(v1coSS, v2coSS, v3coSS, isectVCosSS[i], w);
2059                                 interp_v2_v2v2v2(bucket_bounds_uv[i], uv1co, uv2co, uv3co, w);
2060                         }
2061                 }
2062         }
2063
2064 #ifdef PROJ_DEBUG_PRINT_CLIP
2065         /* include this at the bottom of the above function to debug the output */
2066
2067         {
2068                 /* If there are ever any problems, */
2069                 float test_uv[4][2];
2070                 int i;
2071                 if (is_ortho) rect_to_uvspace_ortho(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2072                 else          rect_to_uvspace_persp(bucket_bounds, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, test_uv, flip);
2073                 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]);
2074
2075                 printf("  [(%f,%f), (%f,%f), (%f,%f)], ", uv1co[0], uv1co[1],   uv2co[0], uv2co[1],    uv3co[0], uv3co[1]);
2076
2077                 printf("[");
2078                 for (i = 0; i < (*tot); i++) {
2079                         printf("(%f, %f),", bucket_bounds_uv[i][0], bucket_bounds_uv[i][1]);
2080                 }
2081                 printf("]),\\\n");
2082         }
2083 #endif
2084 }
2085
2086 /*
2087  * # This script creates faces in a blender scene from printed data above.
2088  *
2089  * project_ls = [
2090  * ...(output from above block)...
2091  * ]
2092  *
2093  * from Blender import Scene, Mesh, Window, sys, Mathutils
2094  *
2095  * import bpy
2096  *
2097  * V = Mathutils.Vector
2098  *
2099  * def main():
2100  *     sce = bpy.data.scenes.active
2101  *
2102  *     for item in project_ls:
2103  *         bb = item[0]
2104  *         uv = item[1]
2105  *         poly = item[2]
2106  *
2107  *         me = bpy.data.meshes.new()
2108  *         ob = sce.objects.new(me)
2109  *
2110  *         me.verts.extend([V(bb[0]).xyz, V(bb[1]).xyz, V(bb[2]).xyz, V(bb[3]).xyz])
2111  *         me.faces.extend([(0,1,2,3),])
2112  *         me.verts.extend([V(uv[0]).xyz, V(uv[1]).xyz, V(uv[2]).xyz])
2113  *         me.faces.extend([(4,5,6),])
2114  *
2115  *         vs = [V(p).xyz for p in poly]
2116  *         print len(vs)
2117  *         l = len(me.verts)
2118  *         me.verts.extend(vs)
2119  *
2120  *         i = l
2121  *         while i < len(me.verts):
2122  *             ii = i + 1
2123  *             if ii == len(me.verts):
2124  *                 ii = l
2125  *             me.edges.extend([i, ii])
2126  *             i += 1
2127  *
2128  * if __name__ == '__main__':
2129  *     main()
2130  */
2131
2132
2133 #undef ISECT_1
2134 #undef ISECT_2
2135 #undef ISECT_3
2136 #undef ISECT_4
2137 #undef ISECT_ALL3
2138 #undef ISECT_ALL4
2139
2140
2141 /* checks if pt is inside a convex 2D polyline, the polyline must be ordered rotating clockwise
2142  * otherwise it would have to test for mixed (line_point_side_v2 > 0.0f) cases */
2143 static bool IsectPoly2Df(const float pt[2], float uv[][2], const int tot)
2144 {
2145         int i;
2146         if (line_point_side_v2(uv[tot - 1], uv[0], pt) < 0.0f)
2147                 return 0;
2148
2149         for (i = 1; i < tot; i++) {
2150                 if (line_point_side_v2(uv[i - 1], uv[i], pt) < 0.0f)
2151                         return 0;
2152
2153         }
2154
2155         return 1;
2156 }
2157 static bool IsectPoly2Df_twoside(const float pt[2], float uv[][2], const int tot)
2158 {
2159         int i;
2160         int side = (line_point_side_v2(uv[tot - 1], uv[0], pt) > 0.0f);
2161
2162         for (i = 1; i < tot; i++) {
2163                 if ((line_point_side_v2(uv[i - 1], uv[i], pt) > 0.0f) != side)
2164                         return 0;
2165
2166         }
2167
2168         return 1;
2169 }
2170
2171 /* One of the most important function for projection painting, since it selects the pixels to be added into each bucket.
2172  * initialize pixels from this face where it intersects with the bucket_index, optionally initialize pixels for removing seams */
2173 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)
2174 {
2175         /* Projection vars, to get the 3D locations into screen space  */
2176         MemArena *arena = ps->arena_mt[thread_index];
2177         LinkNode **bucketPixelNodes = ps->bucketRect + bucket_index;
2178         LinkNode *bucketFaceNodes = ps->bucketFaces[bucket_index];
2179
2180         const MFace *mf = ps->dm_mface + face_index;
2181         const MTFace *tf = ps->dm_mtface + face_index;
2182
2183         /* UV/pixel seeking data */
2184         int x; /* Image X-Pixel */
2185         int y; /* Image Y-Pixel */
2186         float mask;
2187         float uv[2]; /* Image floating point UV - same as x, y but from 0.0-1.0 */
2188
2189         int side;
2190         float *v1coSS, *v2coSS, *v3coSS; /* vert co screen-space, these will be assigned to mf->v1,2,3 or mf->v1,3,4 */
2191
2192         float *vCo[4]; /* vertex screenspace coords */
2193
2194         float w[3], wco[3];
2195
2196         float *uv1co, *uv2co, *uv3co; /* for convenience only, these will be assigned to tf->uv[0],1,2 or tf->uv[0],2,3 */
2197         float pixelScreenCo[4];
2198         bool do_3d_mapping = ps->brush->mtex.brush_map_mode == MTEX_MAP_MODE_3D;
2199
2200         rcti bounds_px; /* ispace bounds */
2201         /* vars for getting uvspace bounds */
2202
2203         float tf_uv_pxoffset[4][2]; /* bucket bounds in UV space so we can init pixels only for this face,  */
2204         float xhalfpx, yhalfpx;
2205         const float ibuf_xf = (float)ibuf->x, ibuf_yf = (float)ibuf->y;
2206
2207         int has_x_isect = 0, has_isect = 0; /* for early loop exit */
2208
2209         int i1, i2, i3;
2210
2211         float uv_clip[8][2];
2212         int uv_clip_tot;
2213         const short is_ortho = ps->is_ortho;
2214         const short is_clone_other = ((ps->brush->imagepaint_tool == PAINT_TOOL_CLONE) && ps->dm_mtface_clone);
2215         const short do_backfacecull = ps->do_backfacecull;
2216         const short do_clip = ps->rv3d ? ps->rv3d->rflag & RV3D_CLIPPING : 0;
2217
2218         vCo[0] = ps->dm_mvert[mf->v1].co;
2219         vCo[1] = ps->dm_mvert[mf->v2].co;
2220         vCo[2] = ps->dm_mvert[mf->v3].co;
2221
2222
2223         /* Use tf_uv_pxoffset instead of tf->uv so we can offset the UV half a pixel
2224          * this is done so we can avoid offsetting all the pixels by 0.5 which causes
2225          * problems when wrapping negative coords */
2226         xhalfpx = (0.5f + (PROJ_GEOM_TOLERANCE * (1.0f / 3.0f))) / ibuf_xf;
2227         yhalfpx = (0.5f + (PROJ_GEOM_TOLERANCE * (1.0f / 4.0f))) / ibuf_yf;
2228
2229         /* Note about (PROJ_GEOM_TOLERANCE/x) above...
2230          * Needed to add this offset since UV coords are often quads aligned to pixels.
2231          * In this case pixels can be exactly between 2 triangles causing nasty
2232          * artifacts.
2233          *
2234          * This workaround can be removed and painting will still work on most cases
2235          * but since the first thing most people try is painting onto a quad- better make it work.
2236          */
2237
2238         tf_uv_pxoffset[0][0] = tf->uv[0][0] - xhalfpx;
2239         tf_uv_pxoffset[0][1] = tf->uv[0][1] - yhalfpx;
2240
2241         tf_uv_pxoffset[1][0] = tf->uv[1][0] - xhalfpx;
2242         tf_uv_pxoffset[1][1] = tf->uv[1][1] - yhalfpx;
2243
2244         tf_uv_pxoffset[2][0] = tf->uv[2][0] - xhalfpx;
2245         tf_uv_pxoffset[2][1] = tf->uv[2][1] - yhalfpx;
2246
2247         if (mf->v4) {
2248                 vCo[3] = ps->dm_mvert[mf->v4].co;
2249
2250                 tf_uv_pxoffset[3][0] = tf->uv[3][0] - xhalfpx;
2251                 tf_uv_pxoffset[3][1] = tf->uv[3][1] - yhalfpx;
2252                 side = 1;
2253         }
2254         else {
2255                 side = 0;
2256         }
2257
2258         do {
2259                 if (side == 1) {
2260                         i1 = 0; i2 = 2; i3 = 3;
2261                 }
2262                 else {
2263                         i1 = 0; i2 = 1; i3 = 2;
2264                 }
2265
2266                 uv1co = tf_uv_pxoffset[i1]; // was tf->uv[i1];
2267                 uv2co = tf_uv_pxoffset[i2]; // was tf->uv[i2];
2268                 uv3co = tf_uv_pxoffset[i3]; // was tf->uv[i3];
2269
2270                 v1coSS = ps->screenCoords[(*(&mf->v1 + i1))];
2271                 v2coSS = ps->screenCoords[(*(&mf->v1 + i2))];
2272                 v3coSS = ps->screenCoords[(*(&mf->v1 + i3))];
2273
2274                 /* This funtion gives is a concave polyline in UV space from the clipped quad and tri*/
2275                 project_bucket_clip_face(
2276                         is_ortho, bucket_bounds,
2277                         v1coSS, v2coSS, v3coSS,
2278                         uv1co, uv2co, uv3co,
2279                         uv_clip, &uv_clip_tot
2280                         );
2281
2282                 /* sometimes this happens, better just allow for 8 intersectiosn even though there should be max 6 */
2283 #if 0
2284                 if (uv_clip_tot > 6) {
2285                         printf("this should never happen! %d\n", uv_clip_tot);
2286                 }
2287 #endif
2288
2289                 if (pixel_bounds_array(uv_clip, &bounds_px, ibuf->x, ibuf->y, uv_clip_tot)) {
2290
2291                         if (clamp_u) {
2292                                 CLAMP(bounds_px.xmin, 0, ibuf->x);
2293                                 CLAMP(bounds_px.xmax, 0, ibuf->x);
2294                         }
2295
2296                         if (clamp_v) {
2297                                 CLAMP(bounds_px.ymin, 0, ibuf->y);
2298                                 CLAMP(bounds_px.ymax, 0, ibuf->y);
2299                         }
2300
2301                         /* clip face and */
2302
2303                         has_isect = 0;
2304                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2305                                 //uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2306                                 uv[1] = (float)y / ibuf_yf; /* use pixel offset UV coords instead */
2307
2308                                 has_x_isect = 0;
2309                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2310                                         //uv[0] = (((float)x) + 0.5f) / ibuf->x;
2311                                         uv[0] = (float)x / ibuf_xf; /* use pixel offset UV coords instead */
2312
2313                                         /* Note about IsectPoly2Df_twoside, checking the face or uv flipping doesnt work,
2314                                          * could check the poly direction but better to do this */
2315                                         if ((do_backfacecull == TRUE  && IsectPoly2Df(uv, uv_clip, uv_clip_tot)) ||
2316                                             (do_backfacecull == FALSE && IsectPoly2Df_twoside(uv, uv_clip, uv_clip_tot)))
2317                                         {
2318
2319                                                 has_x_isect = has_isect = 1;
2320
2321                                                 if (is_ortho) screen_px_from_ortho(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2322                                                 else if (is_clone_other) screen_px_from_persp_ortho_weights(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2323                                                 else screen_px_from_persp(uv, v1coSS, v2coSS, v3coSS, uv1co, uv2co, uv3co, pixelScreenCo, w);
2324
2325                                                 /* a pity we need to get the worldspace pixel location here */
2326                                                 if (do_clip || do_3d_mapping) {
2327                                                         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);
2328                                                         if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2329                                                                 continue; /* Watch out that no code below this needs to run */
2330                                                         }
2331                                                 }
2332
2333                                                 /* Is this UV visible from the view? - raytrace */
2334                                                 /* project_paint_PickFace is less complex, use for testing */
2335                                                 //if (project_paint_PickFace(ps, pixelScreenCo, w, &side) == face_index) {
2336                                                 if ((ps->do_occlude == FALSE) ||
2337                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2338                                                 {
2339                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2340
2341                                                         if (mask > 0.0f) {
2342                                                                 BLI_linklist_prepend_arena(
2343                                                                         bucketPixelNodes,
2344                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index,
2345                                                                                                    image_index, pixelScreenCo, wco, side, w),
2346                                                                         arena
2347                                                                         );
2348                                                         }
2349                                                 }
2350
2351                                         }
2352 //#if 0
2353                                         else if (has_x_isect) {
2354                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2355                                                 break;
2356                                         }
2357 //#endif
2358                                 }
2359
2360
2361 #if 0           /* TODO - investigate why this dosnt work sometimes! it should! */
2362                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2363                                 if (has_x_isect == 0 && has_isect) {
2364                                         break;
2365                                 }
2366 #endif
2367                         }
2368                 }
2369         } while (side--);
2370
2371
2372
2373 #ifndef PROJ_DEBUG_NOSEAMBLEED
2374         if (ps->seam_bleed_px > 0.0f) {
2375                 int face_seam_flag;
2376
2377                 if (ps->thread_tot > 1)
2378                         BLI_lock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2379
2380                 face_seam_flag = ps->faceSeamFlags[face_index];
2381
2382                 /* are any of our edges un-initialized? */
2383                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_NOSEAM1)) == 0 ||
2384                     (face_seam_flag & (PROJ_FACE_SEAM2 | PROJ_FACE_NOSEAM2)) == 0 ||
2385                     (face_seam_flag & (PROJ_FACE_SEAM3 | PROJ_FACE_NOSEAM3)) == 0 ||
2386                     (face_seam_flag & (PROJ_FACE_SEAM4 | PROJ_FACE_NOSEAM4)) == 0)
2387                 {
2388                         project_face_seams_init(ps, face_index, mf->v4);
2389                         face_seam_flag = ps->faceSeamFlags[face_index];
2390                         //printf("seams - %d %d %d %d\n", flag&PROJ_FACE_SEAM1, flag&PROJ_FACE_SEAM2, flag&PROJ_FACE_SEAM3, flag&PROJ_FACE_SEAM4);
2391                 }
2392
2393                 if ((face_seam_flag & (PROJ_FACE_SEAM1 | PROJ_FACE_SEAM2 | PROJ_FACE_SEAM3 | PROJ_FACE_SEAM4)) == 0) {
2394
2395                         if (ps->thread_tot > 1)
2396                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2397
2398                 }
2399                 else {
2400                         /* we have a seam - deal with it! */
2401
2402                         /* Now create new UV's for the seam face */
2403                         float (*outset_uv)[2] = ps->faceSeamUVs[face_index];
2404                         float insetCos[4][3]; /* inset face coords.  NOTE!!! ScreenSace for ortho, Worldspace in prespective view */
2405
2406                         float *vCoSS[4]; /* vertex screenspace coords */
2407
2408                         float bucket_clip_edges[2][2]; /* store the screenspace coords of the face, clipped by the bucket's screen aligned rectangle */
2409                         float edge_verts_inset_clip[2][3];
2410                         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 */
2411
2412                         float seam_subsection[4][2];
2413                         float fac1, fac2, ftot;
2414
2415
2416                         if (outset_uv[0][0] == FLT_MAX) /* first time initialize */
2417                                 uv_image_outset(tf_uv_pxoffset, outset_uv, ps->seam_bleed_px, ibuf->x, ibuf->y, mf->v4 != 0);
2418
2419                         /* ps->faceSeamUVs cant be modified when threading, now this is done we can unlock */
2420                         if (ps->thread_tot > 1)
2421                                 BLI_unlock_thread(LOCK_CUSTOM1);  /* Other threads could be modifying these vars */
2422
2423                         vCoSS[0] = ps->screenCoords[mf->v1];
2424                         vCoSS[1] = ps->screenCoords[mf->v2];
2425                         vCoSS[2] = ps->screenCoords[mf->v3];
2426                         if (mf->v4)
2427                                 vCoSS[3] = ps->screenCoords[mf->v4];
2428
2429                         /* PROJ_FACE_SCALE_SEAM must be slightly less then 1.0f */
2430                         if (is_ortho) {
2431                                 if (mf->v4) scale_quad(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2432                                 else        scale_tri(insetCos, vCoSS, PROJ_FACE_SCALE_SEAM);
2433                         }
2434                         else {
2435                                 if (mf->v4) scale_quad(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2436                                 else        scale_tri(insetCos, vCo, PROJ_FACE_SCALE_SEAM);
2437                         }
2438
2439                         side = 0; /* for triangles this wont need to change */
2440
2441                         for (fidx1 = 0; fidx1 < (mf->v4 ? 4 : 3); fidx1++) {
2442                                 if (mf->v4) fidx2 = (fidx1 == 3) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2,3) -> (1,2,3,0) */
2443                                 else        fidx2 = (fidx1 == 2) ? 0 : fidx1 + 1;  /* next fidx in the face (0,1,2) -> (1,2,0) */
2444
2445                                 if ((face_seam_flag & (1 << fidx1)) && /* 1<<fidx1 -> PROJ_FACE_SEAM# */
2446                                     line_clip_rect2f(bucket_bounds, vCoSS[fidx1], vCoSS[fidx2], bucket_clip_edges[0], bucket_clip_edges[1]))
2447                                 {
2448
2449                                         ftot = len_v2v2(vCoSS[fidx1], vCoSS[fidx2]); /* screenspace edge length */
2450
2451                                         if (ftot > 0.0f) { /* avoid div by zero */
2452                                                 if (mf->v4) {
2453                                                         if (fidx1 == 2 || fidx2 == 2) side = 1;
2454                                                         else side = 0;
2455                                                 }
2456
2457                                                 fac1 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[0]) / ftot;
2458                                                 fac2 = len_v2v2(vCoSS[fidx1], bucket_clip_edges[1]) / ftot;
2459
2460                                                 interp_v2_v2v2(seam_subsection[0], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac1);
2461                                                 interp_v2_v2v2(seam_subsection[1], tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2], fac2);
2462
2463                                                 interp_v2_v2v2(seam_subsection[2], outset_uv[fidx1], outset_uv[fidx2], fac2);
2464                                                 interp_v2_v2v2(seam_subsection[3], outset_uv[fidx1], outset_uv[fidx2], fac1);
2465
2466                                                 /* if the bucket_clip_edges values Z values was kept we could avoid this
2467                                                  * Inset needs to be added so occlusion tests wont hit adjacent faces */
2468                                                 interp_v3_v3v3(edge_verts_inset_clip[0], insetCos[fidx1], insetCos[fidx2], fac1);
2469                                                 interp_v3_v3v3(edge_verts_inset_clip[1], insetCos[fidx1], insetCos[fidx2], fac2);
2470
2471
2472                                                 if (pixel_bounds_uv(seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3], &bounds_px, ibuf->x, ibuf->y, true)) {
2473                                                         /* bounds between the seam rect and the uvspace bucket pixels */
2474
2475                                                         has_isect = 0;
2476                                                         for (y = bounds_px.ymin; y < bounds_px.ymax; y++) {
2477                                                                 // uv[1] = (((float)y) + 0.5f) / (float)ibuf->y;
2478                                                                 uv[1] = (float)y / ibuf_yf; /* use offset uvs instead */
2479
2480                                                                 has_x_isect = 0;
2481                                                                 for (x = bounds_px.xmin; x < bounds_px.xmax; x++) {
2482                                                                         //uv[0] = (((float)x) + 0.5f) / (float)ibuf->x;
2483                                                                         uv[0] = (float)x / ibuf_xf; /* use offset uvs instead */
2484
2485                                                                         /* test we're inside uvspace bucket and triangle bounds */
2486                                                                         if (isect_point_quad_v2(uv, seam_subsection[0], seam_subsection[1], seam_subsection[2], seam_subsection[3])) {
2487                                                                                 float fac;
2488
2489                                                                                 /* We need to find the closest point along the face edge,
2490                                                                                  * getting the screen_px_from_*** wont work because our actual location
2491                                                                                  * is not relevant, since we are outside the face, Use VecLerpf to find
2492                                                                                  * our location on the side of the face's UV */
2493 #if 0
2494                                                                                 if (is_ortho) screen_px_from_ortho(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2495                                                                                 else          screen_px_from_persp(ps, uv, v1co, v2co, v3co, uv1co, uv2co, uv3co, pixelScreenCo);
2496 #endif
2497
2498                                                                                 /* Since this is a seam we need to work out where on the line this pixel is */
2499                                                                                 //fac = line_point_factor_v2(uv, uv_seam_quad[0], uv_seam_quad[1]);
2500
2501                                                                                 fac = line_point_factor_v2(uv, seam_subsection[0], seam_subsection[1]);
2502                                                                                 if      (fac < 0.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[0]); }
2503                                                                                 else if (fac > 1.0f) { copy_v3_v3(pixelScreenCo, edge_verts_inset_clip[1]); }
2504                                                                                 else                 { interp_v3_v3v3(pixelScreenCo, edge_verts_inset_clip[0], edge_verts_inset_clip[1], fac); }
2505
2506                                                                                 if (!is_ortho) {
2507                                                                                         pixelScreenCo[3] = 1.0f;
2508                                                                                         mul_m4_v4((float(*)[4])ps->projectMat, pixelScreenCo); /* cast because of const */
2509                                                                                         pixelScreenCo[0] = (float)(ps->winx * 0.5f) + (ps->winx * 0.5f) * pixelScreenCo[0] / pixelScreenCo[3];
2510                                                                                         pixelScreenCo[1] = (float)(ps->winy * 0.5f) + (ps->winy * 0.5f) * pixelScreenCo[1] / pixelScreenCo[3];
2511                                                                                         pixelScreenCo[2] = pixelScreenCo[2] / pixelScreenCo[3]; /* Use the depth for bucket point occlusion */
2512                                                                                 }
2513
2514                                                                                 if ((ps->do_occlude == FALSE) ||
2515                                                                                     !project_bucket_point_occluded(ps, bucketFaceNodes, face_index, pixelScreenCo))
2516                                                                                 {
2517                                                                                         /* Only bother calculating the weights if we intersect */
2518                                                                                         if (ps->do_mask_normal || ps->dm_mtface_clone) {
2519 #if 1
2520                                                                                                 /* get the UV on the line since we want to copy the pixels from there for bleeding */
2521                                                                                                 float uv_close[2];
2522                                                                                                 float uv_fac = closest_to_line_v2(uv_close, uv, tf_uv_pxoffset[fidx1], tf_uv_pxoffset[fidx2]);
2523                                                                                                 if      (uv_fac < 0.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx1]);
2524                                                                                                 else if (uv_fac > 1.0f) copy_v2_v2(uv_close, tf_uv_pxoffset[fidx2]);
2525
2526                                                                                                 if (side) {
2527                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[2], tf_uv_pxoffset[3], uv_close, w);
2528                                                                                                 }
2529                                                                                                 else {
2530                                                                                                         barycentric_weights_v2(tf_uv_pxoffset[0], tf_uv_pxoffset[1], tf_uv_pxoffset[2], uv_close, w);
2531                                                                                                 }
2532 #else                                                                                   /* this is buggy with quads, don't use for now */
2533
2534                                                                                                 /* Cheat, we know where we are along the edge so work out the weights from that */
2535                                                                                                 uv_fac = fac1 + (uv_fac * (fac2 - fac1));
2536
2537                                                                                                 w[0] = w[1] = w[2] = 0.0;
2538                                                                                                 if (side) {
2539                                                                                                         w[fidx1 ? fidx1 - 1 : 0] = 1.0f - uv_fac;
2540                                                                                                         w[fidx2 ? fidx2 - 1 : 0] = uv_fac;
2541                                                                                                 }
2542                                                                                                 else {
2543                                                                                                         w[fidx1] = 1.0f - uv_fac;
2544                                                                                                         w[fidx2] = uv_fac;
2545                                                                                                 }
2546 #endif
2547                                                                                         }
2548
2549                                                                                         /* a pity we need to get the worldspace pixel location here */
2550                                                                                         if (do_clip || do_3d_mapping) {
2551                                                                                                 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);
2552                                                                                                 else      interp_v3_v3v3v3(wco, ps->dm_mvert[mf->v1].co, ps->dm_mvert[mf->v2].co, ps->dm_mvert[mf->v3].co, w);
2553
2554                                                                                                 if (do_clip && ED_view3d_clipping_test(ps->rv3d, wco, TRUE)) {
2555                                                                                                         continue; /* Watch out that no code below this needs to run */
2556                                                                                                 }
2557                                                                                         }
2558
2559                                                                                         mask = project_paint_uvpixel_mask(ps, face_index, side, w);
2560
2561                                                                                         if (mask > 0.0f) {
2562                                                                                                 BLI_linklist_prepend_arena(
2563                                                                                                         bucketPixelNodes,
2564                                                                                                         project_paint_uvpixel_init(ps, arena, ibuf, x, y, mask, face_index, image_index, pixelScreenCo, wco, side, w),
2565                                                                                                         arena
2566                                                                                                         );
2567                                                                                         }
2568
2569                                                                                 }
2570                                                                         }
2571                                                                         else if (has_x_isect) {
2572                                                                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2573                                                                                 break;
2574                                                                         }
2575                                                                 }
2576
2577 #if 0                           /* TODO - investigate why this dosnt work sometimes! it should! */
2578                                                                 /* no intersection for this entire row, after some intersection above means we can quit now */
2579                                                                 if (has_x_isect == 0 && has_isect) {
2580                                                                         break;
2581                                                                 }
2582 #endif
2583                                                         }
2584                                                 }
2585                                         }
2586                                 }
2587                         }
2588                 }
2589         }
2590 #endif // PROJ_DEBUG_NOSEAMBLEED
2591 }
2592
2593
2594 /* takes floating point screenspace min/max and returns int min/max to be used as indices for ps->bucketRect, ps->bucketFlags */
2595 static void project_paint_bucket_bounds(const ProjPaintState *ps, const float min[2], const float max[2], int bucketMin[2], int bucketMax[2])
2596 {
2597         /* divide by bucketWidth & bucketHeight so the bounds are offset in bucket grid units */
2598         /* 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 */
2599         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 */
2600         bucketMin[1] = (int)((int)(((float)(min[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 0.5f);
2601
2602         bucketMax[0] = (int)((int)(((float)(max[0] - ps->screenMin[0]) / ps->screen_width) * ps->buckets_x) + 1.5f);
2603         bucketMax[1] = (int)((int)(((float)(max[1] - ps->screenMin[1]) / ps->screen_height) * ps->buckets_y) + 1.5f);
2604
2605         /* in case the rect is outside the mesh 2d bounds */
2606         CLAMP(bucketMin[0], 0, ps->buckets_x);
2607         CLAMP(bucketMin[1], 0, ps->buckets_y);
2608
2609         CLAMP(bucketMax[0], 0, ps->buckets_x);
2610         CLAMP(bucketMax[1], 0, ps->buckets_y);
2611 }
2612
2613 /* set bucket_bounds to a screen space-aligned floating point bound-box */
2614 static void project_bucket_bounds(const ProjPaintState *ps, const int bucket_x, const int bucket_y, rctf *bucket_bounds)
2615 {
2616         bucket_bounds->xmin = ps->screenMin[0] + ((bucket_x) * (ps->screen_width / ps->buckets_x));     /* left */
2617         bucket_bounds->xmax = ps->screenMin[0] + ((bucket_x + 1) * (ps->screen_width / ps->buckets_x)); /* right */
2618
2619         bucket_bounds->ymin = ps->screenMin[1] + ((bucket_y) * (ps->screen_height / ps->buckets_y));      /* bottom */
2620         bucket_bounds->ymax = ps->screenMin[1] + ((bucket_y + 1) * (ps->screen_height  / ps->buckets_y)); /* top */
2621 }
2622
2623 /* Fill this bucket with pixels from the faces that intersect it.
2624  *
2625  * have bucket_bounds as an argument so we don't need to give bucket_x/y the rect function needs */
2626 static void project_bucket_init(const ProjPaintState *ps, const int thread_index, const int bucket_index, rctf *bucket_bounds)
2627 {
2628         LinkNode *node;
2629         int face_index, image_index = 0;
2630         ImBuf *ibuf = NULL;
2631         Image *tpage_last = NULL, *tpage;
2632         Image *ima = NULL;
2633
2634         if (ps->image_tot == 1) {
2635                 /* Simple loop, no context switching */
2636                 ibuf = ps->projImages[0].ibuf;
2637                 ima = ps->projImages[0].ima;
2638
2639                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2640                         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);
2641                 }
2642         }
2643         else {
2644
2645                 /* More complicated loop, switch between images */
2646                 for (node = ps->bucketFaces[bucket_index]; node; node = node->next) {
2647                         face_index = GET_INT_FROM_POINTER(node->link);
2648
2649                         /* Image context switching */
2650                         tpage = project_paint_face_image(ps, ps->dm_mtface, face_index);
2651                         if (tpage_last != tpage) {
2652                                 tpage_last = tpage;
2653
2654                                 for (image_index = 0; image_index < ps->image_tot; image_index++) {
2655                                         if (ps->projImages[image_index].ima == tpage_last) {
2656                                                 ibuf = ps->projImages[image_index].ibuf;
2657                                                 ima = ps->projImages[image_index].ima;
2658                                                 break;
2659                                         }
2660                                 }
2661                         }
2662                         /* context switching done */
2663
2664                         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);
2665                 }
2666         }
2667
2668         ps->bucketFlags[bucket_index] |= PROJ_BUCKET_INIT;
2669 }
2670
2671
2672 /* We want to know if a bucket and a face overlap in screen-space
2673  *
2674  * Note, if this ever returns false positives its not that bad, since a face in the bounding area will have its pixels
2675  * calculated when it might not be needed later, (at the moment at least)
2676  * obviously it shouldn't have bugs though */
2677
2678 static bool project_bucket_face_isect(ProjPaintState *ps, int bucket_x, int bucket_y, const MFace *mf)
2679 {
2680         /* TODO - replace this with a tricker method that uses sideofline for all screenCoords's edges against the closest bucket corner */
2681         rctf bucket_bounds;
2682         float p1[2], p2[2], p3[2], p4[2];
2683         float *v, *v1, *v2, *v3, *v4 = NULL;
2684         int fidx;
2685
2686         project_bucket_bounds(ps, bucket_x, bucket_y, &bucket_bounds);
2687
2688         /* Is one of the faces verts in the bucket bounds? */
2689
2690         fidx = mf->v4 ? 3 : 2;
2691         do {
2692                 v = ps->screenCoords[(*(&mf->v1 + fidx))];
2693                 if (BLI_rctf_isect_pt_v(&bucket_bounds, v)) {
2694                         return 1;
2695                 }
2696         } while (fidx--);
2697
2698         v1 = ps->screenCoords[mf->v1];
2699         v2 = ps->screenCoords[mf->v2];
2700         v3 = ps->screenCoords[mf->v3];
2701         if (mf->v4) {
2702                 v4 = ps->screenCoords[mf->v4];
2703         }
2704
2705         p1[0] = bucket_bounds.xmin; p1[1] = bucket_bounds.ymin;
2706         p2[0] = bucket_bounds.xmin; p2[1] = bucket_bounds.ymax;
2707         p3[0] = bucket_bounds.xmax; p3[1] = bucket_bounds.ymax;
2708         p4[0] = bucket_bounds.xmax; p4[1] = bucket_bounds.ymin;
2709
2710         if (mf->v4) {
2711                 if (isect_point_quad_v2(p1, v1, v2, v3, v4) ||
2712                     isect_point_quad_v2(p2, v1, v2, v3, v4) ||
2713                     isect_point_quad_v2(p3, v1, v2, v3, v4) ||
2714                     isect_point_quad_v2(p4, v1, v2, v3, v4) ||
2715
2716                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2717                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3) || isect_line_line_v2(p1, p2, v3, v4)) ||
2718                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3) || isect_line_line_v2(p2, p3, v3, v4)) ||
2719                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3) || isect_line_line_v2(p3, p4, v3, v4)) ||
2720                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3) || isect_line_line_v2(p4, p1, v3, v4)))
2721                 {
2722                         return 1;
2723                 }
2724         }
2725         else {
2726                 if (isect_point_tri_v2(p1, v1, v2, v3) ||
2727                     isect_point_tri_v2(p2, v1, v2, v3) ||
2728                     isect_point_tri_v2(p3, v1, v2, v3) ||
2729                     isect_point_tri_v2(p4, v1, v2, v3) ||
2730                     /* we can avoid testing v3,v1 because another intersection MUST exist if this intersects */
2731                     (isect_line_line_v2(p1, p2, v1, v2) || isect_line_line_v2(p1, p2, v2, v3)) ||
2732                     (isect_line_line_v2(p2, p3, v1, v2) || isect_line_line_v2(p2, p3, v2, v3)) ||
2733                     (isect_line_line_v2(p3, p4, v1, v2) || isect_line_line_v2(p3, p4, v2, v3)) ||
2734                     (isect_line_line_v2(p4, p1, v1, v2) || isect_line_line_v2(p4, p1, v2, v3)))
2735                 {
2736                         return 1;
2737                 }
2738         }
2739
2740         return 0;
2741 }
2742
2743 /* Add faces to the bucket but don't initialize its pixels
2744  * TODO - when painting occluded, sort the faces on their min-Z and only add faces that faces that are not occluded */
2745 static void project_paint_delayed_face_init(ProjPaintState *ps, const MFace *mf, const int face_index)
2746 {
2747         float min[2], max[2], *vCoSS;
2748         int bucketMin[2], bucketMax[2]; /* for  ps->bucketRect indexing */
2749         int fidx, bucket_x, bucket_y;
2750         int has_x_isect = -1, has_isect = 0; /* for early loop exit */
2751         MemArena *arena = ps->arena_mt[0]; /* just use the first thread arena since threading has not started yet */
2752
2753         INIT_MINMAX2(min, max);
2754
2755         fidx = mf->v4 ? 3 : 2;
2756         do {
2757                 vCoSS = ps->screenCoords[*(&mf->v1 + fidx)];
2758                 minmax_v2v2_v2(min, max, vCoSS);
2759         } while (fidx--);
2760
2761         project_paint_bucket_bounds(ps, min, max, bucketMin, bucketMax);
2762
2763         for (bucket_y = bucketMin[1]; bucket_y < bucketMax[1]; bucket_y++) {
2764                 has_x_isect = 0;
2765                 for (bucket_x = bucketMin[0]; bucket_x < bucketMax[0]; bucket_x++) {
2766                         if (project_bucket_face_isect(ps, bucket_x, bucket_y, mf)) {
2767                                 int bucket_index = bucket_x + (bucket_y * ps->buckets_x);
2768                                 BLI_linklist_prepend_arena(
2769                                         &ps->bucketFaces[bucket_index],
2770                                         SET_INT_IN_POINTER(face_index), /* cast to a pointer to shut up the compiler */
2771                                         arena
2772                                         );
2773
2774                                 has_x_isect = has_isect = 1;
2775                         }
2776                         else if (has_x_isect) {
2777                                 /* assuming the face is not a bow-tie - we know we cant intersect again on the X */
2778                                 break;
2779                         }
2780                 }
2781
2782                 /* no intersection for this entire row, after some intersection above means we can quit now */
2783                 if (has_x_isect == 0 && has_isect) {
2784                         break;
2785                 }
2786         }
2787
2788 #ifndef PROJ_DEBUG_NOSEAMBLEED
2789         if (ps->seam_bleed_px > 0.0f) {
2790                 if (!mf->v4) {
2791                         ps->faceSeamFlags[face_index] |= PROJ_FACE_NOSEAM4; /* so this wont show up as an untagged edge */
2792                 }
2793                 **ps->faceSeamUVs[face_index] = FLT_MAX; /* set as uninitialized */
2794         }
2795 #endif
2796 }
2797
2798 /* run once per stroke before projection painting */
2799 static void project_paint_begin(ProjPaintState *ps)
2800 {
2801         /* Viewport vars */
2802         float mat[3][3];
2803
2804         float no[3];
2805
2806         float *projScreenCo; /* Note, we could have 4D vectors are only needed for */
2807         float projMargin;
2808
2809         /* Image Vars - keep track of images we have used */
2810         LinkNode *image_LinkList = NULL;
2811         LinkNode *node;
2812
2813         ProjPaintImage *projIma;
2814         Image *tpage_last = NULL, *tpage;
2815
2816         /* Face vars */
2817         MPoly *mpoly_orig;
2818         MFace *mf;
2819         MTFace *tf;
2820
2821         int a, i; /* generic looping vars */
2822         int image_index = -1, face_index;
2823
2824         /* double lookup */
2825         const int *index_mf_to_mpoly = NULL;
2826         const int *index_mp_to_orig  = NULL;
2827
2828         MVert *mv;
2829
2830         MemArena *arena; /* at the moment this is just ps->arena_mt[0], but use this to show were not multithreading */
2831
2832         const int diameter = 2 * BKE_brush_size_get(ps->scene, ps->brush);
2833
2834         bool reset_threads = false;
2835
2836         /* ---- end defines ---- */
2837
2838         if (ps->source == PROJ_SRC_VIEW)
2839                 ED_view3d_clipping_local(ps->rv3d, ps->ob->obmat);  /* faster clipping lookups */
2840
2841         ps->do_face_sel = ((((Mesh *)ps->ob->data)->editflag & ME_EDIT_PAINT_FACE_SEL) != 0);
2842
2843         /* paint onto the derived mesh */
2844
2845         /* Workaround for subsurf selection, try the display mesh first */
2846         if (ps->source == PROJ_SRC_IMAGE_CAM) {
2847                 /* using render mesh, assume only camera was rendered from */
2848                 ps->dm = mesh_create_derived_render(ps->scene, ps->ob, ps->scene->customdata_mask | CD_MASK_MTFACE);
2849                 ps->dm_release = TRUE;
2850         }
2851         else if (ps->ob->derivedFinal &&
2852                  CustomData_has_layer(&ps->ob->derivedFinal->faceData, CD_MTFACE) &&
2853                  (ps->do_face_sel == false || CustomData_has_layer(&ps->ob->derivedFinal->polyData, CD_ORIGINDEX)))
2854         {
2855                 ps->dm = ps->ob->derivedFinal;
2856                 ps->dm_release = FALSE;
2857         }
2858         else {
2859                 ps->dm = mesh_get_derived_final(
2860                              ps->scene, ps->ob,
2861                              ps->scene->customdata_mask | CD_MASK_MTFACE | (ps->do_face_sel ? CD_ORIGINDEX : 0));
2862                 ps->dm_release = TRUE;
2863         }
2864
2865         if (!CustomData_has_layer(&ps->dm->faceData, CD_MTFACE) ) {
2866
2867                 if (ps->dm_release)
2868                         ps->dm->release(ps->dm);
2869
2870                 ps->dm = NULL;
2871                 return;
2872         }
2873
2874         ps->dm_mvert = ps->dm->getVertArray(ps->dm);
2875         ps->dm_mface = ps->dm->getTessFaceArray(ps->dm);
2876         ps->dm_mtface = ps->dm->getTessFaceDataArray(ps->dm, CD_MTFACE);
2877
2878         ps->dm_totvert = ps->dm->getNumVerts(ps->dm);
2879         ps->dm_totface = ps->dm->getNumTessFaces(ps->dm);
2880
2881         if (ps->do_face_sel) {
2882    &nb