1 /**************************************************************************
3 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
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:
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
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 TUNGSTEN GRAPHICS 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.
26 **************************************************************************/
29 * Binning code for triangles
32 #include "util/u_math.h"
33 #include "util/u_memory.h"
34 #include "util/u_rect.h"
35 #include "util/u_sse.h"
37 #include "lp_setup_context.h"
39 #include "lp_state_fs.h"
40 #include "lp_state_setup.h"
42 #define NUM_CHANNELS 4
44 #if defined(PIPE_ARCH_SSE)
45 #include <emmintrin.h>
49 subpixel_snap(float a
)
51 return util_iround(FIXED_ONE
* a
);
57 return a
* (1.0 / FIXED_ONE
);
67 * Alloc space for a new triangle plus the input.a0/dadx/dady arrays
68 * immediately after it.
69 * The memory is allocated from the per-scene pool, not per-tile.
70 * \param tri_size returns number of bytes allocated
71 * \param num_inputs number of fragment shader inputs
72 * \return pointer to triangle space
74 struct lp_rast_triangle
*
75 lp_setup_alloc_triangle(struct lp_scene
*scene
,
80 unsigned input_array_sz
= NUM_CHANNELS
* (nr_inputs
+ 1) * sizeof(float);
81 unsigned plane_sz
= nr_planes
* sizeof(struct lp_rast_plane
);
82 struct lp_rast_triangle
*tri
;
84 *tri_size
= (sizeof(struct lp_rast_triangle
) +
88 tri
= lp_scene_alloc_aligned( scene
, *tri_size
, 16 );
92 tri
->inputs
.stride
= input_array_sz
;
95 char *a
= (char *)tri
;
96 char *b
= (char *)&GET_PLANES(tri
)[nr_planes
];
97 assert(b
- a
== *tri_size
);
104 lp_setup_print_vertex(struct lp_setup_context
*setup
,
108 const struct lp_setup_variant_key
*key
= &setup
->setup
.variant
->key
;
111 debug_printf(" wpos (%s[0]) xyzw %f %f %f %f\n",
113 v
[0][0], v
[0][1], v
[0][2], v
[0][3]);
115 for (i
= 0; i
< key
->num_inputs
; i
++) {
116 const float *in
= v
[key
->inputs
[i
].src_index
];
118 debug_printf(" in[%d] (%s[%d]) %s%s%s%s ",
120 name
, key
->inputs
[i
].src_index
,
121 (key
->inputs
[i
].usage_mask
& 0x1) ? "x" : " ",
122 (key
->inputs
[i
].usage_mask
& 0x2) ? "y" : " ",
123 (key
->inputs
[i
].usage_mask
& 0x4) ? "z" : " ",
124 (key
->inputs
[i
].usage_mask
& 0x8) ? "w" : " ");
126 for (j
= 0; j
< 4; j
++)
127 if (key
->inputs
[i
].usage_mask
& (1<<j
))
128 debug_printf("%.5f ", in
[j
]);
136 * Print triangle vertex attribs (for debug).
139 lp_setup_print_triangle(struct lp_setup_context
*setup
,
140 const float (*v0
)[4],
141 const float (*v1
)[4],
142 const float (*v2
)[4])
144 debug_printf("triangle\n");
147 const float ex
= v0
[0][0] - v2
[0][0];
148 const float ey
= v0
[0][1] - v2
[0][1];
149 const float fx
= v1
[0][0] - v2
[0][0];
150 const float fy
= v1
[0][1] - v2
[0][1];
152 /* det = cross(e,f).z */
153 const float det
= ex
* fy
- ey
* fx
;
155 debug_printf(" - ccw\n");
157 debug_printf(" - cw\n");
159 debug_printf(" - zero area\n");
162 lp_setup_print_vertex(setup
, "v0", v0
);
163 lp_setup_print_vertex(setup
, "v1", v1
);
164 lp_setup_print_vertex(setup
, "v2", v2
);
170 lp_rast_tri_tab
[MAX_PLANES
+1] = {
171 0, /* should be impossible */
172 LP_RAST_OP_TRIANGLE_1
,
173 LP_RAST_OP_TRIANGLE_2
,
174 LP_RAST_OP_TRIANGLE_3
,
175 LP_RAST_OP_TRIANGLE_4
,
176 LP_RAST_OP_TRIANGLE_5
,
177 LP_RAST_OP_TRIANGLE_6
,
178 LP_RAST_OP_TRIANGLE_7
,
179 LP_RAST_OP_TRIANGLE_8
185 * The primitive covers the whole tile- shade whole tile.
187 * \param tx, ty the tile position in tiles, not pixels
190 lp_setup_whole_tile(struct lp_setup_context
*setup
,
191 const struct lp_rast_shader_inputs
*inputs
,
194 struct lp_scene
*scene
= setup
->scene
;
196 LP_COUNT(nr_fully_covered_64
);
198 /* if variant is opaque and scissor doesn't effect the tile */
199 if (inputs
->opaque
) {
200 if (!scene
->fb
.zsbuf
) {
202 * All previous rendering will be overwritten so reset the bin.
204 lp_scene_bin_reset( scene
, tx
, ty
);
207 LP_COUNT(nr_shade_opaque_64
);
208 return lp_scene_bin_cmd_with_state( scene
, tx
, ty
,
210 LP_RAST_OP_SHADE_TILE_OPAQUE
,
211 lp_rast_arg_inputs(inputs
) );
213 LP_COUNT(nr_shade_64
);
214 return lp_scene_bin_cmd_with_state( scene
, tx
, ty
,
216 LP_RAST_OP_SHADE_TILE
,
217 lp_rast_arg_inputs(inputs
) );
223 * Do basic setup for triangle rasterization and determine which
224 * framebuffer tiles are touched. Put the triangle in the scene's
225 * bins for the tiles which we overlap.
228 do_triangle_ccw(struct lp_setup_context
*setup
,
229 const float (*v0
)[4],
230 const float (*v1
)[4],
231 const float (*v2
)[4],
232 boolean frontfacing
)
234 struct lp_scene
*scene
= setup
->scene
;
235 const struct lp_setup_variant_key
*key
= &setup
->setup
.variant
->key
;
236 struct lp_rast_triangle
*tri
;
237 struct lp_rast_plane
*plane
;
245 lp_setup_print_triangle(setup
, v0
, v1
, v2
);
247 if (setup
->scissor_test
) {
254 /* x/y positions in fixed point */
255 x
[0] = subpixel_snap(v0
[0][0] - setup
->pixel_offset
);
256 x
[1] = subpixel_snap(v1
[0][0] - setup
->pixel_offset
);
257 x
[2] = subpixel_snap(v2
[0][0] - setup
->pixel_offset
);
259 y
[0] = subpixel_snap(v0
[0][1] - setup
->pixel_offset
);
260 y
[1] = subpixel_snap(v1
[0][1] - setup
->pixel_offset
);
261 y
[2] = subpixel_snap(v2
[0][1] - setup
->pixel_offset
);
265 /* Bounding rectangle (in pixels) */
267 /* Yes this is necessary to accurately calculate bounding boxes
268 * with the two fill-conventions we support. GL (normally) ends
269 * up needing a bottom-left fill convention, which requires
270 * slightly different rounding.
272 int adj
= (setup
->pixel_offset
!= 0) ? 1 : 0;
274 bbox
.x0
= (MIN3(x
[0], x
[1], x
[2]) + (FIXED_ONE
-1)) >> FIXED_ORDER
;
275 bbox
.x1
= (MAX3(x
[0], x
[1], x
[2]) + (FIXED_ONE
-1)) >> FIXED_ORDER
;
276 bbox
.y0
= (MIN3(y
[0], y
[1], y
[2]) + (FIXED_ONE
-1) + adj
) >> FIXED_ORDER
;
277 bbox
.y1
= (MAX3(y
[0], y
[1], y
[2]) + (FIXED_ONE
-1) + adj
) >> FIXED_ORDER
;
279 /* Inclusive coordinates:
285 if (bbox
.x1
< bbox
.x0
||
287 if (0) debug_printf("empty bounding box\n");
288 LP_COUNT(nr_culled_tris
);
292 if (!u_rect_test_intersection(&setup
->draw_region
, &bbox
)) {
293 if (0) debug_printf("offscreen\n");
294 LP_COUNT(nr_culled_tris
);
298 /* Can safely discard negative regions, but need to keep hold of
299 * information about when the triangle extends past screen
300 * boundaries. See trimmed_box in lp_setup_bin_triangle().
302 bbox
.x0
= MAX2(bbox
.x0
, 0);
303 bbox
.y0
= MAX2(bbox
.y0
, 0);
305 tri
= lp_setup_alloc_triangle(scene
,
313 tri
->v
[0][0] = v0
[0][0];
314 tri
->v
[1][0] = v1
[0][0];
315 tri
->v
[2][0] = v2
[0][0];
316 tri
->v
[0][1] = v0
[0][1];
317 tri
->v
[1][1] = v1
[0][1];
318 tri
->v
[2][1] = v2
[0][1];
323 /* Setup parameter interpolants:
325 setup
->setup
.variant
->jit_function( v0
,
329 GET_A0(&tri
->inputs
),
330 GET_DADX(&tri
->inputs
),
331 GET_DADY(&tri
->inputs
) );
333 tri
->inputs
.frontfacing
= frontfacing
;
334 tri
->inputs
.disable
= FALSE
;
335 tri
->inputs
.opaque
= setup
->fs
.current
.variant
->opaque
;
338 lp_dump_setup_coef(&setup
->setup
.variant
->key
,
339 (const float (*)[4])GET_A0(&tri
->inputs
),
340 (const float (*)[4])GET_DADX(&tri
->inputs
),
341 (const float (*)[4])GET_DADY(&tri
->inputs
));
343 plane
= GET_PLANES(tri
);
345 #if defined(PIPE_ARCH_SSE)
347 __m128i vertx
, verty
;
348 __m128i shufx
, shufy
;
349 __m128i dcdx
, dcdy
, c
;
351 __m128i dcdx_neg_mask
;
352 __m128i dcdy_neg_mask
;
353 __m128i dcdx_zero_mask
;
354 __m128i top_left_flag
;
355 __m128i c_inc_mask
, c_inc
;
356 __m128i eo
, p0
, p1
, p2
;
357 __m128i zero
= _mm_setzero_si128();
359 vertx
= _mm_loadu_si128((__m128i
*)x
); /* vertex x coords */
360 verty
= _mm_loadu_si128((__m128i
*)y
); /* vertex y coords */
362 shufx
= _mm_shuffle_epi32(vertx
, _MM_SHUFFLE(3,0,2,1));
363 shufy
= _mm_shuffle_epi32(verty
, _MM_SHUFFLE(3,0,2,1));
365 dcdx
= _mm_sub_epi32(verty
, shufy
);
366 dcdy
= _mm_sub_epi32(vertx
, shufx
);
368 dcdx_neg_mask
= _mm_srai_epi32(dcdx
, 31);
369 dcdx_zero_mask
= _mm_cmpeq_epi32(dcdx
, zero
);
370 dcdy_neg_mask
= _mm_srai_epi32(dcdy
, 31);
372 top_left_flag
= _mm_set1_epi32((setup
->pixel_offset
== 0) ? ~0 : 0);
374 c_inc_mask
= _mm_or_si128(dcdx_neg_mask
,
375 _mm_and_si128(dcdx_zero_mask
,
376 _mm_xor_si128(dcdy_neg_mask
,
379 c_inc
= _mm_srli_epi32(c_inc_mask
, 31);
381 c
= _mm_sub_epi32(mm_mullo_epi32(dcdx
, vertx
),
382 mm_mullo_epi32(dcdy
, verty
));
384 c
= _mm_add_epi32(c
, c_inc
);
386 /* Scale up to match c:
388 dcdx
= _mm_slli_epi32(dcdx
, FIXED_ORDER
);
389 dcdy
= _mm_slli_epi32(dcdy
, FIXED_ORDER
);
391 /* Calculate trivial reject values:
393 eo
= _mm_sub_epi32(_mm_andnot_si128(dcdy_neg_mask
, dcdy
),
394 _mm_and_si128(dcdx_neg_mask
, dcdx
));
396 /* ei = _mm_sub_epi32(_mm_sub_epi32(dcdy, dcdx), eo); */
398 /* Pointless transpose which gets undone immediately in
401 transpose4_epi32(&c
, &dcdx
, &dcdy
, &eo
,
402 &p0
, &p1
, &p2
, &unused
);
404 _mm_store_si128((__m128i
*)&plane
[0], p0
);
405 _mm_store_si128((__m128i
*)&plane
[1], p1
);
406 _mm_store_si128((__m128i
*)&plane
[2], p2
);
411 plane
[0].dcdy
= x
[0] - x
[1];
412 plane
[1].dcdy
= x
[1] - x
[2];
413 plane
[2].dcdy
= x
[2] - x
[0];
414 plane
[0].dcdx
= y
[0] - y
[1];
415 plane
[1].dcdx
= y
[1] - y
[2];
416 plane
[2].dcdx
= y
[2] - y
[0];
418 for (i
= 0; i
< 3; i
++) {
419 /* half-edge constants, will be interated over the whole render
422 plane
[i
].c
= plane
[i
].dcdx
* x
[i
] - plane
[i
].dcdy
* y
[i
];
424 /* correct for top-left vs. bottom-left fill convention.
426 * note that we're overloading gl_rasterization_rules to mean
427 * both (0.5,0.5) pixel centers *and* bottom-left filling
430 * GL actually has a top-left filling convention, but GL's
431 * notion of "top" differs from gallium's...
433 * Also, sometimes (in FBO cases) GL will render upside down
434 * to its usual method, in which case it will probably want
435 * to use the opposite, top-left convention.
437 if (plane
[i
].dcdx
< 0) {
438 /* both fill conventions want this - adjust for left edges */
441 else if (plane
[i
].dcdx
== 0) {
442 if (setup
->pixel_offset
== 0) {
443 /* correct for top-left fill convention:
445 if (plane
[i
].dcdy
> 0) plane
[i
].c
++;
448 /* correct for bottom-left fill convention:
450 if (plane
[i
].dcdy
< 0) plane
[i
].c
++;
454 plane
[i
].dcdx
*= FIXED_ONE
;
455 plane
[i
].dcdy
*= FIXED_ONE
;
457 /* find trivial reject offsets for each edge for a single-pixel
458 * sized block. These will be scaled up at each recursive level to
459 * match the active blocksize. Scaling in this way works best if
460 * the blocks are square.
463 if (plane
[i
].dcdx
< 0) plane
[i
].eo
-= plane
[i
].dcdx
;
464 if (plane
[i
].dcdy
> 0) plane
[i
].eo
+= plane
[i
].dcdy
;
470 debug_printf("p0: %08x/%08x/%08x/%08x\n",
476 debug_printf("p1: %08x/%08x/%08x/%08x\n",
482 debug_printf("p0: %08x/%08x/%08x/%08x\n",
491 * When rasterizing scissored tris, use the intersection of the
492 * triangle bounding box and the scissor rect to generate the
495 * This permits us to cut off the triangle "tails" that are present
496 * in the intermediate recursive levels caused when two of the
497 * triangles edges don't diverge quickly enough to trivially reject
498 * exterior blocks from the triangle.
500 * It's not really clear if it's worth worrying about these tails,
501 * but since we generate the planes for each scissored tri, it's
502 * free to trim them in this case.
504 * Note that otherwise, the scissor planes only vary in 'C' value,
505 * and even then only on state-changes. Could alternatively store
506 * these planes elsewhere.
508 if (nr_planes
== 7) {
509 const struct u_rect
*scissor
= &setup
->scissor
;
513 plane
[3].c
= 1-scissor
->x0
;
518 plane
[4].c
= scissor
->x1
+1;
523 plane
[5].c
= 1-scissor
->y0
;
528 plane
[6].c
= scissor
->y1
+1;
532 return lp_setup_bin_triangle( setup
, tri
, &bbox
, nr_planes
);
536 * Round to nearest less or equal power of two of the input.
538 * Undefined if no bit set exists, so code should check against 0 first.
540 static INLINE
uint32_t
541 floor_pot(uint32_t n
)
543 #if defined(PIPE_CC_GCC) && defined(PIPE_ARCH_X86)
563 lp_setup_bin_triangle( struct lp_setup_context
*setup
,
564 struct lp_rast_triangle
*tri
,
565 const struct u_rect
*bbox
,
568 struct lp_scene
*scene
= setup
->scene
;
569 struct u_rect trimmed_box
= *bbox
;
572 /* What is the largest power-of-two boundary this triangle crosses:
574 int dx
= floor_pot((bbox
->x0
^ bbox
->x1
) |
575 (bbox
->y0
^ bbox
->y1
));
577 /* The largest dimension of the rasterized area of the triangle
578 * (aligned to a 4x4 grid), rounded down to the nearest power of two:
580 int sz
= floor_pot((bbox
->x1
- (bbox
->x0
& ~3)) |
581 (bbox
->y1
- (bbox
->y0
& ~3)));
583 /* Now apply scissor, etc to the bounding box. Could do this
584 * earlier, but it confuses the logic for tri-16 and would force
585 * the rasterizer to also respect scissor, etc, just for the rare
586 * cases where a small triangle extends beyond the scissor.
588 u_rect_find_intersection(&setup
->draw_region
, &trimmed_box
);
590 /* Determine which tile(s) intersect the triangle's bounding box
594 int ix0
= bbox
->x0
/ TILE_SIZE
;
595 int iy0
= bbox
->y0
/ TILE_SIZE
;
596 unsigned px
= bbox
->x0
& 63 & ~3;
597 unsigned py
= bbox
->y0
& 63 & ~3;
599 assert(iy0
== bbox
->y1
/ TILE_SIZE
&&
600 ix0
== bbox
->x1
/ TILE_SIZE
);
602 if (nr_planes
== 3) {
605 /* Triangle is contained in a single 4x4 stamp:
607 assert(px
+ 4 <= TILE_SIZE
);
608 assert(py
+ 4 <= TILE_SIZE
);
609 return lp_scene_bin_cmd_with_state( scene
, ix0
, iy0
,
611 LP_RAST_OP_TRIANGLE_3_4
,
612 lp_rast_arg_triangle_contained(tri
, px
, py
) );
617 /* Triangle is contained in a single 16x16 block:
621 * The 16x16 block is only 4x4 aligned, and can exceed the tile
622 * dimensions if the triangle is 16 pixels in one dimension but 4
623 * in the other. So budge the 16x16 back inside the tile.
625 px
= MIN2(px
, TILE_SIZE
- 16);
626 py
= MIN2(py
, TILE_SIZE
- 16);
628 assert(px
+ 16 <= TILE_SIZE
);
629 assert(py
+ 16 <= TILE_SIZE
);
631 return lp_scene_bin_cmd_with_state( scene
, ix0
, iy0
,
633 LP_RAST_OP_TRIANGLE_3_16
,
634 lp_rast_arg_triangle_contained(tri
, px
, py
) );
637 else if (nr_planes
== 4 && sz
< 16)
639 px
= MIN2(px
, TILE_SIZE
- 16);
640 py
= MIN2(py
, TILE_SIZE
- 16);
642 assert(px
+ 16 <= TILE_SIZE
);
643 assert(py
+ 16 <= TILE_SIZE
);
645 return lp_scene_bin_cmd_with_state(scene
, ix0
, iy0
,
647 LP_RAST_OP_TRIANGLE_4_16
,
648 lp_rast_arg_triangle_contained(tri
, px
, py
));
652 /* Triangle is contained in a single tile:
654 return lp_scene_bin_cmd_with_state( scene
, ix0
, iy0
, setup
->fs
.stored
,
655 lp_rast_tri_tab
[nr_planes
],
656 lp_rast_arg_triangle(tri
, (1<<nr_planes
)-1) );
660 struct lp_rast_plane
*plane
= GET_PLANES(tri
);
665 int xstep
[MAX_PLANES
];
666 int ystep
[MAX_PLANES
];
669 int ix0
= trimmed_box
.x0
/ TILE_SIZE
;
670 int iy0
= trimmed_box
.y0
/ TILE_SIZE
;
671 int ix1
= trimmed_box
.x1
/ TILE_SIZE
;
672 int iy1
= trimmed_box
.y1
/ TILE_SIZE
;
674 for (i
= 0; i
< nr_planes
; i
++) {
676 plane
[i
].dcdy
* iy0
* TILE_SIZE
-
677 plane
[i
].dcdx
* ix0
* TILE_SIZE
);
679 ei
[i
] = (plane
[i
].dcdy
-
681 plane
[i
].eo
) << TILE_ORDER
;
683 eo
[i
] = plane
[i
].eo
<< TILE_ORDER
;
684 xstep
[i
] = -(plane
[i
].dcdx
<< TILE_ORDER
);
685 ystep
[i
] = plane
[i
].dcdy
<< TILE_ORDER
;
690 /* Test tile-sized blocks against the triangle.
691 * Discard blocks fully outside the tri. If the block is fully
692 * contained inside the tri, bin an lp_rast_shade_tile command.
693 * Else, bin a lp_rast_triangle command.
695 for (y
= iy0
; y
<= iy1
; y
++)
697 boolean in
= FALSE
; /* are we inside the triangle? */
700 for (i
= 0; i
< nr_planes
; i
++)
703 for (x
= ix0
; x
<= ix1
; x
++)
708 for (i
= 0; i
< nr_planes
; i
++) {
709 int planeout
= cx
[i
] + eo
[i
];
710 int planepartial
= cx
[i
] + ei
[i
] - 1;
711 out
|= (planeout
>> 31);
712 partial
|= (planepartial
>> 31) & (1<<i
);
718 break; /* exiting triangle, all done with this row */
719 LP_COUNT(nr_empty_64
);
722 /* Not trivially accepted by at least one plane -
723 * rasterize/shade partial tile
725 int count
= util_bitcount(partial
);
728 if (!lp_scene_bin_cmd_with_state( scene
, x
, y
,
730 lp_rast_tri_tab
[count
],
731 lp_rast_arg_triangle(tri
, partial
) ))
734 LP_COUNT(nr_partially_covered_64
);
737 /* triangle covers the whole tile- shade whole tile */
738 LP_COUNT(nr_fully_covered_64
);
740 if (!lp_setup_whole_tile(setup
, &tri
->inputs
, x
, y
))
744 /* Iterate cx values across the region:
746 for (i
= 0; i
< nr_planes
; i
++)
750 /* Iterate c values down the region:
752 for (i
= 0; i
< nr_planes
; i
++)
760 /* Need to disable any partially binned triangle. This is easier
761 * than trying to locate all the triangle, shade-tile, etc,
762 * commands which may have been binned.
764 tri
->inputs
.disable
= TRUE
;
770 * Try to draw the triangle, restart the scene on failure.
772 static void retry_triangle_ccw( struct lp_setup_context
*setup
,
773 const float (*v0
)[4],
774 const float (*v1
)[4],
775 const float (*v2
)[4],
778 if (!do_triangle_ccw( setup
, v0
, v1
, v2
, front
))
780 if (!lp_setup_flush_and_restart(setup
))
783 if (!do_triangle_ccw( setup
, v0
, v1
, v2
, front
))
789 calc_area(const float (*v0
)[4],
790 const float (*v1
)[4],
791 const float (*v2
)[4])
793 float dx01
= v0
[0][0] - v1
[0][0];
794 float dy01
= v0
[0][1] - v1
[0][1];
795 float dx20
= v2
[0][0] - v0
[0][0];
796 float dy20
= v2
[0][1] - v0
[0][1];
797 return dx01
* dy20
- dx20
* dy01
;
802 * Draw triangle if it's CW, cull otherwise.
804 static void triangle_cw( struct lp_setup_context
*setup
,
805 const float (*v0
)[4],
806 const float (*v1
)[4],
807 const float (*v2
)[4] )
809 float area
= calc_area(v0
, v1
, v2
);
812 retry_triangle_ccw(setup
, v0
, v2
, v1
, !setup
->ccw_is_frontface
);
816 static void triangle_ccw( struct lp_setup_context
*setup
,
817 const float (*v0
)[4],
818 const float (*v1
)[4],
819 const float (*v2
)[4])
821 float area
= calc_area(v0
, v1
, v2
);
824 retry_triangle_ccw(setup
, v0
, v1
, v2
, setup
->ccw_is_frontface
);
828 * Draw triangle whether it's CW or CCW.
830 static void triangle_both( struct lp_setup_context
*setup
,
831 const float (*v0
)[4],
832 const float (*v1
)[4],
833 const float (*v2
)[4] )
835 float area
= calc_area(v0
, v1
, v2
);
838 assert(!util_is_inf_or_nan(v0
[0][0]));
839 assert(!util_is_inf_or_nan(v0
[0][1]));
840 assert(!util_is_inf_or_nan(v1
[0][0]));
841 assert(!util_is_inf_or_nan(v1
[0][1]));
842 assert(!util_is_inf_or_nan(v2
[0][0]));
843 assert(!util_is_inf_or_nan(v2
[0][1]));
844 assert(!util_is_inf_or_nan(area
));
848 retry_triangle_ccw( setup
, v0
, v1
, v2
, setup
->ccw_is_frontface
);
849 else if (area
< 0.0f
)
850 retry_triangle_ccw( setup
, v0
, v2
, v1
, !setup
->ccw_is_frontface
);
854 static void triangle_nop( struct lp_setup_context
*setup
,
855 const float (*v0
)[4],
856 const float (*v1
)[4],
857 const float (*v2
)[4] )
863 lp_setup_choose_triangle( struct lp_setup_context
*setup
)
865 switch (setup
->cullmode
) {
867 setup
->triangle
= triangle_both
;
870 setup
->triangle
= setup
->ccw_is_frontface
? triangle_ccw
: triangle_cw
;
872 case PIPE_FACE_FRONT
:
873 setup
->triangle
= setup
->ccw_is_frontface
? triangle_cw
: triangle_ccw
;
876 setup
->triangle
= triangle_nop
;