• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /**************************************************************************
2  *
3  * Copyright 2007 VMware, Inc.
4  * All Rights Reserved.
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sub license, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice (including the
15  * next paragraph) shall be included in all copies or substantial portions
16  * of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25  *
26  **************************************************************************/
27 
28 /*
29  * Binning code for triangles
30  */
31 
32 #include "util/u_math.h"
33 #include "util/u_memory.h"
34 #include "util/u_rect.h"
35 #include "util/u_sse.h"
36 #include "lp_perf.h"
37 #include "lp_setup_context.h"
38 #include "lp_rast.h"
39 #include "lp_state_fs.h"
40 #include "lp_state_setup.h"
41 #include "lp_context.h"
42 
43 #include <inttypes.h>
44 
45 #define NUM_CHANNELS 4
46 
47 #if defined(PIPE_ARCH_SSE)
48 #include <emmintrin.h>
49 #elif defined(_ARCH_PWR8) && defined(PIPE_ARCH_LITTLE_ENDIAN)
50 #include <altivec.h>
51 #include "util/u_pwr8.h"
52 #endif
53 
54 #if !defined(PIPE_ARCH_SSE)
55 
56 static inline int
subpixel_snap(float a)57 subpixel_snap(float a)
58 {
59    return util_iround(FIXED_ONE * a);
60 }
61 
62 #endif
63 
64 /* Position and area in fixed point coordinates */
65 struct fixed_position {
66    int32_t x[4];
67    int32_t y[4];
68    int32_t dx01;
69    int32_t dy01;
70    int32_t dx20;
71    int32_t dy20;
72    int64_t area;
73 };
74 
75 
76 /**
77  * Alloc space for a new triangle plus the input.a0/dadx/dady arrays
78  * immediately after it.
79  * The memory is allocated from the per-scene pool, not per-tile.
80  * \param tri_size  returns number of bytes allocated
81  * \param num_inputs  number of fragment shader inputs
82  * \return pointer to triangle space
83  */
84 struct lp_rast_triangle *
lp_setup_alloc_triangle(struct lp_scene * scene,unsigned nr_inputs,unsigned nr_planes,unsigned * tri_size)85 lp_setup_alloc_triangle(struct lp_scene *scene,
86                         unsigned nr_inputs,
87                         unsigned nr_planes,
88                         unsigned *tri_size)
89 {
90    unsigned input_array_sz = NUM_CHANNELS * (nr_inputs + 1) * sizeof(float);
91    unsigned plane_sz = nr_planes * sizeof(struct lp_rast_plane);
92    struct lp_rast_triangle *tri;
93 
94    STATIC_ASSERT(sizeof(struct lp_rast_plane) % 8 == 0);
95 
96    *tri_size = (sizeof(struct lp_rast_triangle) +
97                 3 * input_array_sz +
98                 plane_sz);
99 
100    tri = lp_scene_alloc_aligned( scene, *tri_size, 16 );
101    if (!tri)
102       return NULL;
103 
104    tri->inputs.stride = input_array_sz;
105 
106    {
107       char *a = (char *)tri;
108       char *b = (char *)&GET_PLANES(tri)[nr_planes];
109       assert(b - a == *tri_size);
110    }
111 
112    return tri;
113 }
114 
115 void
lp_setup_print_vertex(struct lp_setup_context * setup,const char * name,const float (* v)[4])116 lp_setup_print_vertex(struct lp_setup_context *setup,
117                       const char *name,
118                       const float (*v)[4])
119 {
120    const struct lp_setup_variant_key *key = &setup->setup.variant->key;
121    int i, j;
122 
123    debug_printf("   wpos (%s[0]) xyzw %f %f %f %f\n",
124                 name,
125                 v[0][0], v[0][1], v[0][2], v[0][3]);
126 
127    for (i = 0; i < key->num_inputs; i++) {
128       const float *in = v[key->inputs[i].src_index];
129 
130       debug_printf("  in[%d] (%s[%d]) %s%s%s%s ",
131                    i,
132                    name, key->inputs[i].src_index,
133                    (key->inputs[i].usage_mask & 0x1) ? "x" : " ",
134                    (key->inputs[i].usage_mask & 0x2) ? "y" : " ",
135                    (key->inputs[i].usage_mask & 0x4) ? "z" : " ",
136                    (key->inputs[i].usage_mask & 0x8) ? "w" : " ");
137 
138       for (j = 0; j < 4; j++)
139          if (key->inputs[i].usage_mask & (1<<j))
140             debug_printf("%.5f ", in[j]);
141 
142       debug_printf("\n");
143    }
144 }
145 
146 
147 /**
148  * Print triangle vertex attribs (for debug).
149  */
150 void
lp_setup_print_triangle(struct lp_setup_context * setup,const float (* v0)[4],const float (* v1)[4],const float (* v2)[4])151 lp_setup_print_triangle(struct lp_setup_context *setup,
152                         const float (*v0)[4],
153                         const float (*v1)[4],
154                         const float (*v2)[4])
155 {
156    debug_printf("triangle\n");
157 
158    {
159       const float ex = v0[0][0] - v2[0][0];
160       const float ey = v0[0][1] - v2[0][1];
161       const float fx = v1[0][0] - v2[0][0];
162       const float fy = v1[0][1] - v2[0][1];
163 
164       /* det = cross(e,f).z */
165       const float det = ex * fy - ey * fx;
166       if (det < 0.0f)
167          debug_printf("   - ccw\n");
168       else if (det > 0.0f)
169          debug_printf("   - cw\n");
170       else
171          debug_printf("   - zero area\n");
172    }
173 
174    lp_setup_print_vertex(setup, "v0", v0);
175    lp_setup_print_vertex(setup, "v1", v1);
176    lp_setup_print_vertex(setup, "v2", v2);
177 }
178 
179 
180 #define MAX_PLANES 8
181 static unsigned
182 lp_rast_tri_tab[MAX_PLANES+1] = {
183    0,               /* should be impossible */
184    LP_RAST_OP_TRIANGLE_1,
185    LP_RAST_OP_TRIANGLE_2,
186    LP_RAST_OP_TRIANGLE_3,
187    LP_RAST_OP_TRIANGLE_4,
188    LP_RAST_OP_TRIANGLE_5,
189    LP_RAST_OP_TRIANGLE_6,
190    LP_RAST_OP_TRIANGLE_7,
191    LP_RAST_OP_TRIANGLE_8
192 };
193 
194 static unsigned
195 lp_rast_32_tri_tab[MAX_PLANES+1] = {
196    0,               /* should be impossible */
197    LP_RAST_OP_TRIANGLE_32_1,
198    LP_RAST_OP_TRIANGLE_32_2,
199    LP_RAST_OP_TRIANGLE_32_3,
200    LP_RAST_OP_TRIANGLE_32_4,
201    LP_RAST_OP_TRIANGLE_32_5,
202    LP_RAST_OP_TRIANGLE_32_6,
203    LP_RAST_OP_TRIANGLE_32_7,
204    LP_RAST_OP_TRIANGLE_32_8
205 };
206 
207 
208 
209 /**
210  * The primitive covers the whole tile- shade whole tile.
211  *
212  * \param tx, ty  the tile position in tiles, not pixels
213  */
214 static boolean
lp_setup_whole_tile(struct lp_setup_context * setup,const struct lp_rast_shader_inputs * inputs,int tx,int ty)215 lp_setup_whole_tile(struct lp_setup_context *setup,
216                     const struct lp_rast_shader_inputs *inputs,
217                     int tx, int ty)
218 {
219    struct lp_scene *scene = setup->scene;
220 
221    LP_COUNT(nr_fully_covered_64);
222 
223    /* if variant is opaque and scissor doesn't effect the tile */
224    if (inputs->opaque) {
225       /* Several things prevent this optimization from working:
226        * - For layered rendering we can't determine if this covers the same layer
227        * as previous rendering (or in case of clears those actually always cover
228        * all layers so optimization is impossible). Need to use fb_max_layer and
229        * not setup->layer_slot to determine this since even if there's currently
230        * no slot assigned previous rendering could have used one.
231        * - If there were any Begin/End query commands in the scene then those
232        * would get removed which would be very wrong. Furthermore, if queries
233        * were just active we also can't do the optimization since to get
234        * accurate query results we unfortunately need to execute the rendering
235        * commands.
236        */
237       if (!scene->fb.zsbuf && scene->fb_max_layer == 0 && !scene->had_queries) {
238          /*
239           * All previous rendering will be overwritten so reset the bin.
240           */
241          lp_scene_bin_reset( scene, tx, ty );
242       }
243 
244       LP_COUNT(nr_shade_opaque_64);
245       return lp_scene_bin_cmd_with_state( scene, tx, ty,
246                                           setup->fs.stored,
247                                           LP_RAST_OP_SHADE_TILE_OPAQUE,
248                                           lp_rast_arg_inputs(inputs) );
249    } else {
250       LP_COUNT(nr_shade_64);
251       return lp_scene_bin_cmd_with_state( scene, tx, ty,
252                                           setup->fs.stored,
253                                           LP_RAST_OP_SHADE_TILE,
254                                           lp_rast_arg_inputs(inputs) );
255    }
256 }
257 
258 
259 /**
260  * Do basic setup for triangle rasterization and determine which
261  * framebuffer tiles are touched.  Put the triangle in the scene's
262  * bins for the tiles which we overlap.
263  */
264 static boolean
do_triangle_ccw(struct lp_setup_context * setup,struct fixed_position * position,const float (* v0)[4],const float (* v1)[4],const float (* v2)[4],boolean frontfacing)265 do_triangle_ccw(struct lp_setup_context *setup,
266                 struct fixed_position* position,
267                 const float (*v0)[4],
268                 const float (*v1)[4],
269                 const float (*v2)[4],
270                 boolean frontfacing )
271 {
272    struct lp_scene *scene = setup->scene;
273    const struct lp_setup_variant_key *key = &setup->setup.variant->key;
274    struct lp_rast_triangle *tri;
275    struct lp_rast_plane *plane;
276    const struct u_rect *scissor;
277    struct u_rect bbox, bboxpos;
278    boolean s_planes[4];
279    unsigned tri_bytes;
280    int nr_planes = 3;
281    unsigned viewport_index = 0;
282    unsigned layer = 0;
283    const float (*pv)[4];
284 
285    /* Area should always be positive here */
286    assert(position->area > 0);
287 
288    if (0)
289       lp_setup_print_triangle(setup, v0, v1, v2);
290 
291    if (setup->flatshade_first) {
292       pv = v0;
293    }
294    else {
295       pv = v2;
296    }
297    if (setup->viewport_index_slot > 0) {
298       unsigned *udata = (unsigned*)pv[setup->viewport_index_slot];
299       viewport_index = lp_clamp_viewport_idx(*udata);
300    }
301    if (setup->layer_slot > 0) {
302       layer = *(unsigned*)pv[setup->layer_slot];
303       layer = MIN2(layer, scene->fb_max_layer);
304    }
305 
306    /* Bounding rectangle (in pixels) */
307    {
308       /* Yes this is necessary to accurately calculate bounding boxes
309        * with the two fill-conventions we support.  GL (normally) ends
310        * up needing a bottom-left fill convention, which requires
311        * slightly different rounding.
312        */
313       int adj = (setup->bottom_edge_rule != 0) ? 1 : 0;
314 
315       /* Inclusive x0, exclusive x1 */
316       bbox.x0 =  MIN3(position->x[0], position->x[1], position->x[2]) >> FIXED_ORDER;
317       bbox.x1 = (MAX3(position->x[0], position->x[1], position->x[2]) - 1) >> FIXED_ORDER;
318 
319       /* Inclusive / exclusive depending upon adj (bottom-left or top-right) */
320       bbox.y0 = (MIN3(position->y[0], position->y[1], position->y[2]) + adj) >> FIXED_ORDER;
321       bbox.y1 = (MAX3(position->y[0], position->y[1], position->y[2]) - 1 + adj) >> FIXED_ORDER;
322    }
323 
324    if (bbox.x1 < bbox.x0 ||
325        bbox.y1 < bbox.y0) {
326       if (0) debug_printf("empty bounding box\n");
327       LP_COUNT(nr_culled_tris);
328       return TRUE;
329    }
330 
331    if (!u_rect_test_intersection(&setup->draw_regions[viewport_index], &bbox)) {
332       if (0) debug_printf("offscreen\n");
333       LP_COUNT(nr_culled_tris);
334       return TRUE;
335    }
336 
337    bboxpos = bbox;
338 
339    /* Can safely discard negative regions, but need to keep hold of
340     * information about when the triangle extends past screen
341     * boundaries.  See trimmed_box in lp_setup_bin_triangle().
342     */
343    bboxpos.x0 = MAX2(bboxpos.x0, 0);
344    bboxpos.y0 = MAX2(bboxpos.y0, 0);
345 
346    nr_planes = 3;
347    /*
348     * Determine how many scissor planes we need, that is drop scissor
349     * edges if the bounding box of the tri is fully inside that edge.
350     */
351    if (setup->scissor_test) {
352       /* why not just use draw_regions */
353       scissor = &setup->scissors[viewport_index];
354       scissor_planes_needed(s_planes, &bboxpos, scissor);
355       nr_planes += s_planes[0] + s_planes[1] + s_planes[2] + s_planes[3];
356    }
357 
358    tri = lp_setup_alloc_triangle(scene,
359                                  key->num_inputs,
360                                  nr_planes,
361                                  &tri_bytes);
362    if (!tri)
363       return FALSE;
364 
365 #ifdef DEBUG
366    tri->v[0][0] = v0[0][0];
367    tri->v[1][0] = v1[0][0];
368    tri->v[2][0] = v2[0][0];
369    tri->v[0][1] = v0[0][1];
370    tri->v[1][1] = v1[0][1];
371    tri->v[2][1] = v2[0][1];
372 #endif
373 
374    LP_COUNT(nr_tris);
375 
376    /* Setup parameter interpolants:
377     */
378    setup->setup.variant->jit_function(v0, v1, v2,
379                                       frontfacing,
380                                       GET_A0(&tri->inputs),
381                                       GET_DADX(&tri->inputs),
382                                       GET_DADY(&tri->inputs));
383 
384    tri->inputs.frontfacing = frontfacing;
385    tri->inputs.disable = FALSE;
386    tri->inputs.opaque = setup->fs.current.variant->opaque;
387    tri->inputs.layer = layer;
388    tri->inputs.viewport_index = viewport_index;
389 
390    if (0)
391       lp_dump_setup_coef(&setup->setup.variant->key,
392                          (const float (*)[4])GET_A0(&tri->inputs),
393                          (const float (*)[4])GET_DADX(&tri->inputs),
394                          (const float (*)[4])GET_DADY(&tri->inputs));
395 
396    plane = GET_PLANES(tri);
397 
398 #if defined(PIPE_ARCH_SSE)
399    if (1) {
400       __m128i vertx, verty;
401       __m128i shufx, shufy;
402       __m128i dcdx, dcdy;
403       __m128i cdx02, cdx13, cdy02, cdy13, c02, c13;
404       __m128i c01, c23, unused;
405       __m128i dcdx_neg_mask;
406       __m128i dcdy_neg_mask;
407       __m128i dcdx_zero_mask;
408       __m128i top_left_flag, c_dec;
409       __m128i eo, p0, p1, p2;
410       __m128i zero = _mm_setzero_si128();
411 
412       vertx = _mm_load_si128((__m128i *)position->x); /* vertex x coords */
413       verty = _mm_load_si128((__m128i *)position->y); /* vertex y coords */
414 
415       shufx = _mm_shuffle_epi32(vertx, _MM_SHUFFLE(3,0,2,1));
416       shufy = _mm_shuffle_epi32(verty, _MM_SHUFFLE(3,0,2,1));
417 
418       dcdx = _mm_sub_epi32(verty, shufy);
419       dcdy = _mm_sub_epi32(vertx, shufx);
420 
421       dcdx_neg_mask = _mm_srai_epi32(dcdx, 31);
422       dcdx_zero_mask = _mm_cmpeq_epi32(dcdx, zero);
423       dcdy_neg_mask = _mm_srai_epi32(dcdy, 31);
424 
425       top_left_flag = _mm_set1_epi32((setup->bottom_edge_rule == 0) ? ~0 : 0);
426 
427       c_dec = _mm_or_si128(dcdx_neg_mask,
428                            _mm_and_si128(dcdx_zero_mask,
429                                          _mm_xor_si128(dcdy_neg_mask,
430                                                        top_left_flag)));
431 
432       /*
433        * 64 bit arithmetic.
434        * Note we need _signed_ mul (_mm_mul_epi32) which we emulate.
435        */
436       cdx02 = mm_mullohi_epi32(dcdx, vertx, &cdx13);
437       cdy02 = mm_mullohi_epi32(dcdy, verty, &cdy13);
438       c02 = _mm_sub_epi64(cdx02, cdy02);
439       c13 = _mm_sub_epi64(cdx13, cdy13);
440       c02 = _mm_sub_epi64(c02, _mm_shuffle_epi32(c_dec,
441                                                  _MM_SHUFFLE(2,2,0,0)));
442       c13 = _mm_sub_epi64(c13, _mm_shuffle_epi32(c_dec,
443                                                  _MM_SHUFFLE(3,3,1,1)));
444 
445       /*
446        * Useful for very small fbs/tris (or fewer subpixel bits) only:
447        * c = _mm_sub_epi32(mm_mullo_epi32(dcdx, vertx),
448        *                   mm_mullo_epi32(dcdy, verty));
449        *
450        * c = _mm_sub_epi32(c, c_dec);
451        */
452 
453       /* Scale up to match c:
454        */
455       dcdx = _mm_slli_epi32(dcdx, FIXED_ORDER);
456       dcdy = _mm_slli_epi32(dcdy, FIXED_ORDER);
457 
458       /*
459        * Calculate trivial reject values:
460        * Note eo cannot overflow even if dcdx/dcdy would already have
461        * 31 bits (which they shouldn't have). This is because eo
462        * is never negative (albeit if we rely on that need to be careful...)
463        */
464       eo = _mm_sub_epi32(_mm_andnot_si128(dcdy_neg_mask, dcdy),
465                          _mm_and_si128(dcdx_neg_mask, dcdx));
466 
467       /* ei = _mm_sub_epi32(_mm_sub_epi32(dcdy, dcdx), eo); */
468 
469       /*
470        * Pointless transpose which gets undone immediately in
471        * rasterization.
472        * It is actually difficult to do away with it - would essentially
473        * need GET_PLANES_DX, GET_PLANES_DY etc., but the calculations
474        * for this then would need to depend on the number of planes.
475        * The transpose is quite special here due to c being 64bit...
476        * The store has to be unaligned (unless we'd make the plane size
477        * a multiple of 128), and of course storing eo separately...
478        */
479       c01 = _mm_unpacklo_epi64(c02, c13);
480       c23 = _mm_unpackhi_epi64(c02, c13);
481       transpose2_64_2_32(&c01, &c23, &dcdx, &dcdy,
482                          &p0, &p1, &p2, &unused);
483       _mm_storeu_si128((__m128i *)&plane[0], p0);
484       plane[0].eo = (uint32_t)_mm_cvtsi128_si32(eo);
485       _mm_storeu_si128((__m128i *)&plane[1], p1);
486       eo = _mm_shuffle_epi32(eo, _MM_SHUFFLE(3,2,0,1));
487       plane[1].eo = (uint32_t)_mm_cvtsi128_si32(eo);
488       _mm_storeu_si128((__m128i *)&plane[2], p2);
489       eo = _mm_shuffle_epi32(eo, _MM_SHUFFLE(0,0,0,2));
490       plane[2].eo = (uint32_t)_mm_cvtsi128_si32(eo);
491    } else
492 #elif defined(_ARCH_PWR8) && defined(PIPE_ARCH_LITTLE_ENDIAN)
493    /*
494     * XXX this code is effectively disabled for all practical purposes,
495     * as the allowed fb size is tiny if FIXED_ORDER is 8.
496     */
497    if (setup->fb.width <= MAX_FIXED_LENGTH32 &&
498        setup->fb.height <= MAX_FIXED_LENGTH32 &&
499        (bbox.x1 - bbox.x0) <= MAX_FIXED_LENGTH32 &&
500        (bbox.y1 - bbox.y0) <= MAX_FIXED_LENGTH32) {
501       unsigned int bottom_edge;
502       __m128i vertx, verty;
503       __m128i shufx, shufy;
504       __m128i dcdx, dcdy, c;
505       __m128i unused;
506       __m128i dcdx_neg_mask;
507       __m128i dcdy_neg_mask;
508       __m128i dcdx_zero_mask;
509       __m128i top_left_flag;
510       __m128i c_inc_mask, c_inc;
511       __m128i eo, p0, p1, p2;
512       __m128i_union vshuf_mask;
513       __m128i zero = vec_splats((unsigned char) 0);
514       PIPE_ALIGN_VAR(16) int32_t temp_vec[4];
515 
516 #ifdef PIPE_ARCH_LITTLE_ENDIAN
517       vshuf_mask.i[0] = 0x07060504;
518       vshuf_mask.i[1] = 0x0B0A0908;
519       vshuf_mask.i[2] = 0x03020100;
520       vshuf_mask.i[3] = 0x0F0E0D0C;
521 #else
522       vshuf_mask.i[0] = 0x00010203;
523       vshuf_mask.i[1] = 0x0C0D0E0F;
524       vshuf_mask.i[2] = 0x04050607;
525       vshuf_mask.i[3] = 0x08090A0B;
526 #endif
527 
528       /* vertex x coords */
529       vertx = vec_load_si128((const uint32_t *) position->x);
530       /* vertex y coords */
531       verty = vec_load_si128((const uint32_t *) position->y);
532 
533       shufx = vec_perm (vertx, vertx, vshuf_mask.m128i);
534       shufy = vec_perm (verty, verty, vshuf_mask.m128i);
535 
536       dcdx = vec_sub_epi32(verty, shufy);
537       dcdy = vec_sub_epi32(vertx, shufx);
538 
539       dcdx_neg_mask = vec_srai_epi32(dcdx, 31);
540       dcdx_zero_mask = vec_cmpeq_epi32(dcdx, zero);
541       dcdy_neg_mask = vec_srai_epi32(dcdy, 31);
542 
543       bottom_edge = (setup->bottom_edge_rule == 0) ? ~0 : 0;
544       top_left_flag = (__m128i) vec_splats(bottom_edge);
545 
546       c_inc_mask = vec_or(dcdx_neg_mask,
547                                 vec_and(dcdx_zero_mask,
548                                               vec_xor(dcdy_neg_mask,
549                                                             top_left_flag)));
550 
551       c_inc = vec_srli_epi32(c_inc_mask, 31);
552 
553       c = vec_sub_epi32(vec_mullo_epi32(dcdx, vertx),
554                         vec_mullo_epi32(dcdy, verty));
555 
556       c = vec_add_epi32(c, c_inc);
557 
558       /* Scale up to match c:
559        */
560       dcdx = vec_slli_epi32(dcdx, FIXED_ORDER);
561       dcdy = vec_slli_epi32(dcdy, FIXED_ORDER);
562 
563       /* Calculate trivial reject values:
564        */
565       eo = vec_sub_epi32(vec_andnot_si128(dcdy_neg_mask, dcdy),
566                          vec_and(dcdx_neg_mask, dcdx));
567 
568       /* ei = _mm_sub_epi32(_mm_sub_epi32(dcdy, dcdx), eo); */
569 
570       /* Pointless transpose which gets undone immediately in
571        * rasterization:
572        */
573       transpose4_epi32(&c, &dcdx, &dcdy, &eo,
574                        &p0, &p1, &p2, &unused);
575 
576 #define STORE_PLANE(plane, vec) do {                  \
577          vec_store_si128((uint32_t *)&temp_vec, vec); \
578          plane.c    = (int64_t)temp_vec[0];           \
579          plane.dcdx = temp_vec[1];                    \
580          plane.dcdy = temp_vec[2];                    \
581          plane.eo   = temp_vec[3];                    \
582       } while(0)
583 
584       STORE_PLANE(plane[0], p0);
585       STORE_PLANE(plane[1], p1);
586       STORE_PLANE(plane[2], p2);
587 #undef STORE_PLANE
588    } else
589 #endif
590    {
591       int i;
592       plane[0].dcdy = position->dx01;
593       plane[1].dcdy = position->x[1] - position->x[2];
594       plane[2].dcdy = position->dx20;
595       plane[0].dcdx = position->dy01;
596       plane[1].dcdx = position->y[1] - position->y[2];
597       plane[2].dcdx = position->dy20;
598 
599       for (i = 0; i < 3; i++) {
600          /* half-edge constants, will be iterated over the whole render
601           * target.
602           */
603          plane[i].c = IMUL64(plane[i].dcdx, position->x[i]) -
604                       IMUL64(plane[i].dcdy, position->y[i]);
605 
606          /* correct for top-left vs. bottom-left fill convention.
607           */
608          if (plane[i].dcdx < 0) {
609             /* both fill conventions want this - adjust for left edges */
610             plane[i].c++;
611          }
612          else if (plane[i].dcdx == 0) {
613             if (setup->bottom_edge_rule == 0){
614                /* correct for top-left fill convention:
615                 */
616                if (plane[i].dcdy > 0) plane[i].c++;
617             }
618             else {
619                /* correct for bottom-left fill convention:
620                 */
621                if (plane[i].dcdy < 0) plane[i].c++;
622             }
623          }
624 
625          /* Scale up to match c:
626           */
627          assert((plane[i].dcdx << FIXED_ORDER) >> FIXED_ORDER == plane[i].dcdx);
628          assert((plane[i].dcdy << FIXED_ORDER) >> FIXED_ORDER == plane[i].dcdy);
629          plane[i].dcdx <<= FIXED_ORDER;
630          plane[i].dcdy <<= FIXED_ORDER;
631 
632          /* find trivial reject offsets for each edge for a single-pixel
633           * sized block.  These will be scaled up at each recursive level to
634           * match the active blocksize.  Scaling in this way works best if
635           * the blocks are square.
636           */
637          plane[i].eo = 0;
638          if (plane[i].dcdx < 0) plane[i].eo -= plane[i].dcdx;
639          if (plane[i].dcdy > 0) plane[i].eo += plane[i].dcdy;
640       }
641    }
642 
643    if (0) {
644       debug_printf("p0: %"PRIx64"/%08x/%08x/%08x\n",
645                    plane[0].c,
646                    plane[0].dcdx,
647                    plane[0].dcdy,
648                    plane[0].eo);
649 
650       debug_printf("p1: %"PRIx64"/%08x/%08x/%08x\n",
651                    plane[1].c,
652                    plane[1].dcdx,
653                    plane[1].dcdy,
654                    plane[1].eo);
655 
656       debug_printf("p2: %"PRIx64"/%08x/%08x/%08x\n",
657                    plane[2].c,
658                    plane[2].dcdx,
659                    plane[2].dcdy,
660                    plane[2].eo);
661    }
662 
663 
664    /*
665     * When rasterizing scissored tris, use the intersection of the
666     * triangle bounding box and the scissor rect to generate the
667     * scissor planes.
668     *
669     * This permits us to cut off the triangle "tails" that are present
670     * in the intermediate recursive levels caused when two of the
671     * triangles edges don't diverge quickly enough to trivially reject
672     * exterior blocks from the triangle.
673     *
674     * It's not really clear if it's worth worrying about these tails,
675     * but since we generate the planes for each scissored tri, it's
676     * free to trim them in this case.
677     *
678     * Note that otherwise, the scissor planes only vary in 'C' value,
679     * and even then only on state-changes.  Could alternatively store
680     * these planes elsewhere.
681     * (Or only store the c value together with a bit indicating which
682     * scissor edge this is, so rasterization would treat them differently
683     * (easier to evaluate) to ordinary planes.)
684     */
685    if (nr_planes > 3) {
686       /* why not just use draw_regions */
687       struct lp_rast_plane *plane_s = &plane[3];
688 
689       if (s_planes[0]) {
690          plane_s->dcdx = -1 << 8;
691          plane_s->dcdy = 0;
692          plane_s->c = (1-scissor->x0) << 8;
693          plane_s->eo = 1 << 8;
694          plane_s++;
695       }
696       if (s_planes[1]) {
697          plane_s->dcdx = 1 << 8;
698          plane_s->dcdy = 0;
699          plane_s->c = (scissor->x1+1) << 8;
700          plane_s->eo = 0 << 8;
701          plane_s++;
702       }
703       if (s_planes[2]) {
704          plane_s->dcdx = 0;
705          plane_s->dcdy = 1 << 8;
706          plane_s->c = (1-scissor->y0) << 8;
707          plane_s->eo = 1 << 8;
708          plane_s++;
709       }
710       if (s_planes[3]) {
711          plane_s->dcdx = 0;
712          plane_s->dcdy = -1 << 8;
713          plane_s->c = (scissor->y1+1) << 8;
714          plane_s->eo = 0;
715          plane_s++;
716       }
717       assert(plane_s == &plane[nr_planes]);
718    }
719 
720    return lp_setup_bin_triangle(setup, tri, &bbox, &bboxpos, nr_planes, viewport_index);
721 }
722 
723 /*
724  * Round to nearest less or equal power of two of the input.
725  *
726  * Undefined if no bit set exists, so code should check against 0 first.
727  */
728 static inline uint32_t
floor_pot(uint32_t n)729 floor_pot(uint32_t n)
730 {
731 #if defined(PIPE_CC_GCC) && (defined(PIPE_ARCH_X86) || defined(PIPE_ARCH_X86_64))
732    if (n == 0)
733       return 0;
734 
735    __asm__("bsr %1,%0"
736           : "=r" (n)
737           : "rm" (n));
738    return 1 << n;
739 #else
740    n |= (n >>  1);
741    n |= (n >>  2);
742    n |= (n >>  4);
743    n |= (n >>  8);
744    n |= (n >> 16);
745    return n - (n >> 1);
746 #endif
747 }
748 
749 
750 boolean
lp_setup_bin_triangle(struct lp_setup_context * setup,struct lp_rast_triangle * tri,const struct u_rect * bboxorig,const struct u_rect * bbox,int nr_planes,unsigned viewport_index)751 lp_setup_bin_triangle(struct lp_setup_context *setup,
752                       struct lp_rast_triangle *tri,
753                       const struct u_rect *bboxorig,
754                       const struct u_rect *bbox,
755                       int nr_planes,
756                       unsigned viewport_index)
757 {
758    struct lp_scene *scene = setup->scene;
759    struct u_rect trimmed_box = *bbox;
760    int i;
761    /* What is the largest power-of-two boundary this triangle crosses:
762     */
763    int dx = floor_pot((bbox->x0 ^ bbox->x1) |
764 		      (bbox->y0 ^ bbox->y1));
765 
766    /* The largest dimension of the rasterized area of the triangle
767     * (aligned to a 4x4 grid), rounded down to the nearest power of two:
768     */
769    int max_sz = ((bbox->x1 - (bbox->x0 & ~3)) |
770                  (bbox->y1 - (bbox->y0 & ~3)));
771    int sz = floor_pot(max_sz);
772 
773    /*
774     * NOTE: It is important to use the original bounding box
775     * which might contain negative values here, because if the
776     * plane math may overflow or not with the 32bit rasterization
777     * functions depends on the original extent of the triangle.
778     */
779    int max_szorig = ((bboxorig->x1 - (bboxorig->x0 & ~3)) |
780                      (bboxorig->y1 - (bboxorig->y0 & ~3)));
781    boolean use_32bits = max_szorig <= MAX_FIXED_LENGTH32;
782 
783    /* Now apply scissor, etc to the bounding box.  Could do this
784     * earlier, but it confuses the logic for tri-16 and would force
785     * the rasterizer to also respect scissor, etc, just for the rare
786     * cases where a small triangle extends beyond the scissor.
787     */
788    u_rect_find_intersection(&setup->draw_regions[viewport_index],
789                             &trimmed_box);
790 
791    /* Determine which tile(s) intersect the triangle's bounding box
792     */
793    if (dx < TILE_SIZE)
794    {
795       int ix0 = bbox->x0 / TILE_SIZE;
796       int iy0 = bbox->y0 / TILE_SIZE;
797       unsigned px = bbox->x0 & 63 & ~3;
798       unsigned py = bbox->y0 & 63 & ~3;
799 
800       assert(iy0 == bbox->y1 / TILE_SIZE &&
801 	     ix0 == bbox->x1 / TILE_SIZE);
802 
803       if (nr_planes == 3) {
804          if (sz < 4)
805          {
806             /* Triangle is contained in a single 4x4 stamp:
807              */
808             assert(px + 4 <= TILE_SIZE);
809             assert(py + 4 <= TILE_SIZE);
810             return lp_scene_bin_cmd_with_state( scene, ix0, iy0,
811                                                 setup->fs.stored,
812                                                 use_32bits ?
813                                                 LP_RAST_OP_TRIANGLE_32_3_4 :
814                                                 LP_RAST_OP_TRIANGLE_3_4,
815                                                 lp_rast_arg_triangle_contained(tri, px, py) );
816          }
817 
818          if (sz < 16)
819          {
820             /* Triangle is contained in a single 16x16 block:
821              */
822 
823             /*
824              * The 16x16 block is only 4x4 aligned, and can exceed the tile
825              * dimensions if the triangle is 16 pixels in one dimension but 4
826              * in the other. So budge the 16x16 back inside the tile.
827              */
828             px = MIN2(px, TILE_SIZE - 16);
829             py = MIN2(py, TILE_SIZE - 16);
830 
831             assert(px + 16 <= TILE_SIZE);
832             assert(py + 16 <= TILE_SIZE);
833 
834             return lp_scene_bin_cmd_with_state( scene, ix0, iy0,
835                                                 setup->fs.stored,
836                                                 use_32bits ?
837                                                 LP_RAST_OP_TRIANGLE_32_3_16 :
838                                                 LP_RAST_OP_TRIANGLE_3_16,
839                                                 lp_rast_arg_triangle_contained(tri, px, py) );
840          }
841       }
842       else if (nr_planes == 4 && sz < 16)
843       {
844          px = MIN2(px, TILE_SIZE - 16);
845          py = MIN2(py, TILE_SIZE - 16);
846 
847          assert(px + 16 <= TILE_SIZE);
848          assert(py + 16 <= TILE_SIZE);
849 
850          return lp_scene_bin_cmd_with_state(scene, ix0, iy0,
851                                             setup->fs.stored,
852                                             use_32bits ?
853                                             LP_RAST_OP_TRIANGLE_32_4_16 :
854                                             LP_RAST_OP_TRIANGLE_4_16,
855                                             lp_rast_arg_triangle_contained(tri, px, py));
856       }
857 
858 
859       /* Triangle is contained in a single tile:
860        */
861       return lp_scene_bin_cmd_with_state(
862          scene, ix0, iy0, setup->fs.stored,
863          use_32bits ? lp_rast_32_tri_tab[nr_planes] : lp_rast_tri_tab[nr_planes],
864          lp_rast_arg_triangle(tri, (1<<nr_planes)-1));
865    }
866    else
867    {
868       struct lp_rast_plane *plane = GET_PLANES(tri);
869       int64_t c[MAX_PLANES];
870       int64_t ei[MAX_PLANES];
871 
872       int64_t eo[MAX_PLANES];
873       int64_t xstep[MAX_PLANES];
874       int64_t ystep[MAX_PLANES];
875       int x, y;
876 
877       int ix0 = trimmed_box.x0 / TILE_SIZE;
878       int iy0 = trimmed_box.y0 / TILE_SIZE;
879       int ix1 = trimmed_box.x1 / TILE_SIZE;
880       int iy1 = trimmed_box.y1 / TILE_SIZE;
881 
882       for (i = 0; i < nr_planes; i++) {
883          c[i] = (plane[i].c +
884                  IMUL64(plane[i].dcdy, iy0) * TILE_SIZE -
885                  IMUL64(plane[i].dcdx, ix0) * TILE_SIZE);
886 
887          ei[i] = (plane[i].dcdy -
888                   plane[i].dcdx -
889                   (int64_t)plane[i].eo) << TILE_ORDER;
890 
891          eo[i] = (int64_t)plane[i].eo << TILE_ORDER;
892          xstep[i] = -(((int64_t)plane[i].dcdx) << TILE_ORDER);
893          ystep[i] = ((int64_t)plane[i].dcdy) << TILE_ORDER;
894       }
895 
896 
897 
898       /* Test tile-sized blocks against the triangle.
899        * Discard blocks fully outside the tri.  If the block is fully
900        * contained inside the tri, bin an lp_rast_shade_tile command.
901        * Else, bin a lp_rast_triangle command.
902        */
903       for (y = iy0; y <= iy1; y++)
904       {
905          boolean in = FALSE;  /* are we inside the triangle? */
906          int64_t cx[MAX_PLANES];
907 
908          for (i = 0; i < nr_planes; i++)
909             cx[i] = c[i];
910 
911          for (x = ix0; x <= ix1; x++)
912          {
913             int out = 0;
914             int partial = 0;
915 
916             for (i = 0; i < nr_planes; i++) {
917                int64_t planeout = cx[i] + eo[i];
918                int64_t planepartial = cx[i] + ei[i] - 1;
919                out |= (int) (planeout >> 63);
920                partial |= ((int) (planepartial >> 63)) & (1<<i);
921             }
922 
923             if (out) {
924                /* do nothing */
925                if (in)
926                   break;  /* exiting triangle, all done with this row */
927                LP_COUNT(nr_empty_64);
928             }
929             else if (partial) {
930                /* Not trivially accepted by at least one plane -
931                 * rasterize/shade partial tile
932                 */
933                int count = util_bitcount(partial);
934                in = TRUE;
935 
936                if (!lp_scene_bin_cmd_with_state( scene, x, y,
937                                                  setup->fs.stored,
938                                                  use_32bits ?
939                                                  lp_rast_32_tri_tab[count] :
940                                                  lp_rast_tri_tab[count],
941                                                  lp_rast_arg_triangle(tri, partial) ))
942                   goto fail;
943 
944                LP_COUNT(nr_partially_covered_64);
945             }
946             else {
947                /* triangle covers the whole tile- shade whole tile */
948                LP_COUNT(nr_fully_covered_64);
949                in = TRUE;
950                if (!lp_setup_whole_tile(setup, &tri->inputs, x, y))
951                   goto fail;
952             }
953 
954             /* Iterate cx values across the region: */
955             for (i = 0; i < nr_planes; i++)
956                cx[i] += xstep[i];
957          }
958 
959          /* Iterate c values down the region: */
960          for (i = 0; i < nr_planes; i++)
961             c[i] += ystep[i];
962       }
963    }
964 
965    return TRUE;
966 
967 fail:
968    /* Need to disable any partially binned triangle.  This is easier
969     * than trying to locate all the triangle, shade-tile, etc,
970     * commands which may have been binned.
971     */
972    tri->inputs.disable = TRUE;
973    return FALSE;
974 }
975 
976 
977 /**
978  * Try to draw the triangle, restart the scene on failure.
979  */
retry_triangle_ccw(struct lp_setup_context * setup,struct fixed_position * position,const float (* v0)[4],const float (* v1)[4],const float (* v2)[4],boolean front)980 static void retry_triangle_ccw( struct lp_setup_context *setup,
981                                 struct fixed_position* position,
982                                 const float (*v0)[4],
983                                 const float (*v1)[4],
984                                 const float (*v2)[4],
985                                 boolean front)
986 {
987    if (!do_triangle_ccw( setup, position, v0, v1, v2, front ))
988    {
989       if (!lp_setup_flush_and_restart(setup))
990          return;
991 
992       if (!do_triangle_ccw( setup, position, v0, v1, v2, front ))
993          return;
994    }
995 }
996 
997 /**
998  * Calculate fixed position data for a triangle
999  * It is unfortunate we need to do that here (as we need area
1000  * calculated in fixed point), as there's quite some code duplication
1001  * to what is done in the jit setup prog.
1002  */
1003 static inline void
calc_fixed_position(struct lp_setup_context * setup,struct fixed_position * position,const float (* v0)[4],const float (* v1)[4],const float (* v2)[4])1004 calc_fixed_position(struct lp_setup_context *setup,
1005                     struct fixed_position* position,
1006                     const float (*v0)[4],
1007                     const float (*v1)[4],
1008                     const float (*v2)[4])
1009 {
1010    /*
1011     * The rounding may not be quite the same with PIPE_ARCH_SSE
1012     * (util_iround right now only does nearest/even on x87,
1013     * otherwise nearest/away-from-zero).
1014     * Both should be acceptable, I think.
1015     */
1016 #if defined(PIPE_ARCH_SSE)
1017    __m128 v0r, v1r;
1018    __m128 vxy0xy2, vxy1xy0;
1019    __m128i vxy0xy2i, vxy1xy0i;
1020    __m128i dxdy0120, x0x2y0y2, x1x0y1y0, x0120, y0120;
1021    __m128 pix_offset = _mm_set1_ps(setup->pixel_offset);
1022    __m128 fixed_one = _mm_set1_ps((float)FIXED_ONE);
1023    v0r = _mm_castpd_ps(_mm_load_sd((double *)v0[0]));
1024    vxy0xy2 = _mm_loadh_pi(v0r, (__m64 *)v2[0]);
1025    v1r = _mm_castpd_ps(_mm_load_sd((double *)v1[0]));
1026    vxy1xy0 = _mm_movelh_ps(v1r, vxy0xy2);
1027    vxy0xy2 = _mm_sub_ps(vxy0xy2, pix_offset);
1028    vxy1xy0 = _mm_sub_ps(vxy1xy0, pix_offset);
1029    vxy0xy2 = _mm_mul_ps(vxy0xy2, fixed_one);
1030    vxy1xy0 = _mm_mul_ps(vxy1xy0, fixed_one);
1031    vxy0xy2i = _mm_cvtps_epi32(vxy0xy2);
1032    vxy1xy0i = _mm_cvtps_epi32(vxy1xy0);
1033    dxdy0120 = _mm_sub_epi32(vxy0xy2i, vxy1xy0i);
1034    _mm_store_si128((__m128i *)&position->dx01, dxdy0120);
1035    /*
1036     * For the mul, would need some more shuffles, plus emulation
1037     * for the signed mul (without sse41), so don't bother.
1038     */
1039    x0x2y0y2 = _mm_shuffle_epi32(vxy0xy2i, _MM_SHUFFLE(3,1,2,0));
1040    x1x0y1y0 = _mm_shuffle_epi32(vxy1xy0i, _MM_SHUFFLE(3,1,2,0));
1041    x0120 = _mm_unpacklo_epi32(x0x2y0y2, x1x0y1y0);
1042    y0120 = _mm_unpackhi_epi32(x0x2y0y2, x1x0y1y0);
1043    _mm_store_si128((__m128i *)&position->x[0], x0120);
1044    _mm_store_si128((__m128i *)&position->y[0], y0120);
1045 
1046 #else
1047    position->x[0] = subpixel_snap(v0[0][0] - setup->pixel_offset);
1048    position->x[1] = subpixel_snap(v1[0][0] - setup->pixel_offset);
1049    position->x[2] = subpixel_snap(v2[0][0] - setup->pixel_offset);
1050    position->x[3] = 0; // should be unused
1051 
1052    position->y[0] = subpixel_snap(v0[0][1] - setup->pixel_offset);
1053    position->y[1] = subpixel_snap(v1[0][1] - setup->pixel_offset);
1054    position->y[2] = subpixel_snap(v2[0][1] - setup->pixel_offset);
1055    position->y[3] = 0; // should be unused
1056 
1057    position->dx01 = position->x[0] - position->x[1];
1058    position->dy01 = position->y[0] - position->y[1];
1059 
1060    position->dx20 = position->x[2] - position->x[0];
1061    position->dy20 = position->y[2] - position->y[0];
1062 #endif
1063 
1064    position->area = IMUL64(position->dx01, position->dy20) -
1065          IMUL64(position->dx20, position->dy01);
1066 }
1067 
1068 
1069 /**
1070  * Rotate a triangle, flipping its clockwise direction,
1071  * Swaps values for xy[0] and xy[1]
1072  */
1073 static inline void
rotate_fixed_position_01(struct fixed_position * position)1074 rotate_fixed_position_01( struct fixed_position* position )
1075 {
1076    int x, y;
1077 
1078    x = position->x[1];
1079    y = position->y[1];
1080    position->x[1] = position->x[0];
1081    position->y[1] = position->y[0];
1082    position->x[0] = x;
1083    position->y[0] = y;
1084 
1085    position->dx01 = -position->dx01;
1086    position->dy01 = -position->dy01;
1087    position->dx20 = position->x[2] - position->x[0];
1088    position->dy20 = position->y[2] - position->y[0];
1089 
1090    position->area = -position->area;
1091 }
1092 
1093 
1094 /**
1095  * Rotate a triangle, flipping its clockwise direction,
1096  * Swaps values for xy[1] and xy[2]
1097  */
1098 static inline void
rotate_fixed_position_12(struct fixed_position * position)1099 rotate_fixed_position_12( struct fixed_position* position )
1100 {
1101    int x, y;
1102 
1103    x = position->x[2];
1104    y = position->y[2];
1105    position->x[2] = position->x[1];
1106    position->y[2] = position->y[1];
1107    position->x[1] = x;
1108    position->y[1] = y;
1109 
1110    x = position->dx01;
1111    y = position->dy01;
1112    position->dx01 = -position->dx20;
1113    position->dy01 = -position->dy20;
1114    position->dx20 = -x;
1115    position->dy20 = -y;
1116 
1117    position->area = -position->area;
1118 }
1119 
1120 
1121 /**
1122  * Draw triangle if it's CW, cull otherwise.
1123  */
triangle_cw(struct lp_setup_context * setup,const float (* v0)[4],const float (* v1)[4],const float (* v2)[4])1124 static void triangle_cw(struct lp_setup_context *setup,
1125                         const float (*v0)[4],
1126                         const float (*v1)[4],
1127                         const float (*v2)[4])
1128 {
1129    PIPE_ALIGN_VAR(16) struct fixed_position position;
1130 
1131    calc_fixed_position(setup, &position, v0, v1, v2);
1132 
1133    if (position.area < 0) {
1134       if (setup->flatshade_first) {
1135          rotate_fixed_position_12(&position);
1136          retry_triangle_ccw(setup, &position, v0, v2, v1, !setup->ccw_is_frontface);
1137       } else {
1138          rotate_fixed_position_01(&position);
1139          retry_triangle_ccw(setup, &position, v1, v0, v2, !setup->ccw_is_frontface);
1140       }
1141    }
1142 }
1143 
1144 
triangle_ccw(struct lp_setup_context * setup,const float (* v0)[4],const float (* v1)[4],const float (* v2)[4])1145 static void triangle_ccw(struct lp_setup_context *setup,
1146                          const float (*v0)[4],
1147                          const float (*v1)[4],
1148                          const float (*v2)[4])
1149 {
1150    PIPE_ALIGN_VAR(16) struct fixed_position position;
1151 
1152    calc_fixed_position(setup, &position, v0, v1, v2);
1153 
1154    if (position.area > 0)
1155       retry_triangle_ccw(setup, &position, v0, v1, v2, setup->ccw_is_frontface);
1156 }
1157 
1158 /**
1159  * Draw triangle whether it's CW or CCW.
1160  */
triangle_both(struct lp_setup_context * setup,const float (* v0)[4],const float (* v1)[4],const float (* v2)[4])1161 static void triangle_both(struct lp_setup_context *setup,
1162                           const float (*v0)[4],
1163                           const float (*v1)[4],
1164                           const float (*v2)[4])
1165 {
1166    PIPE_ALIGN_VAR(16) struct fixed_position position;
1167    struct llvmpipe_context *lp_context = (struct llvmpipe_context *)setup->pipe;
1168 
1169    if (lp_context->active_statistics_queries &&
1170        !llvmpipe_rasterization_disabled(lp_context)) {
1171       lp_context->pipeline_statistics.c_primitives++;
1172    }
1173 
1174    calc_fixed_position(setup, &position, v0, v1, v2);
1175 
1176    if (0) {
1177       assert(!util_is_inf_or_nan(v0[0][0]));
1178       assert(!util_is_inf_or_nan(v0[0][1]));
1179       assert(!util_is_inf_or_nan(v1[0][0]));
1180       assert(!util_is_inf_or_nan(v1[0][1]));
1181       assert(!util_is_inf_or_nan(v2[0][0]));
1182       assert(!util_is_inf_or_nan(v2[0][1]));
1183    }
1184 
1185    if (position.area > 0)
1186       retry_triangle_ccw( setup, &position, v0, v1, v2, setup->ccw_is_frontface );
1187    else if (position.area < 0) {
1188       if (setup->flatshade_first) {
1189          rotate_fixed_position_12( &position );
1190          retry_triangle_ccw( setup, &position, v0, v2, v1, !setup->ccw_is_frontface );
1191       } else {
1192          rotate_fixed_position_01( &position );
1193          retry_triangle_ccw( setup, &position, v1, v0, v2, !setup->ccw_is_frontface );
1194       }
1195    }
1196 }
1197 
1198 
triangle_nop(struct lp_setup_context * setup,const float (* v0)[4],const float (* v1)[4],const float (* v2)[4])1199 static void triangle_nop( struct lp_setup_context *setup,
1200 			  const float (*v0)[4],
1201 			  const float (*v1)[4],
1202 			  const float (*v2)[4] )
1203 {
1204 }
1205 
1206 
1207 void
lp_setup_choose_triangle(struct lp_setup_context * setup)1208 lp_setup_choose_triangle( struct lp_setup_context *setup )
1209 {
1210    switch (setup->cullmode) {
1211    case PIPE_FACE_NONE:
1212       setup->triangle = triangle_both;
1213       break;
1214    case PIPE_FACE_BACK:
1215       setup->triangle = setup->ccw_is_frontface ? triangle_ccw : triangle_cw;
1216       break;
1217    case PIPE_FACE_FRONT:
1218       setup->triangle = setup->ccw_is_frontface ? triangle_cw : triangle_ccw;
1219       break;
1220    default:
1221       setup->triangle = triangle_nop;
1222       break;
1223    }
1224 }
1225