/************************************************************************** * * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas. * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sub license, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice (including the * next paragraph) shall be included in all copies or substantial portions * of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * **************************************************************************/ /* * Binning code for triangles */ #include "util/u_math.h" #include "util/u_memory.h" #include "util/u_rect.h" #include "util/u_sse.h" #include "lp_perf.h" #include "lp_setup_context.h" #include "lp_rast.h" #include "lp_state_fs.h" #include "lp_state_setup.h" #include "lp_context.h" #define NUM_CHANNELS 4 #if defined(PIPE_ARCH_SSE) #include #endif static INLINE int subpixel_snap(float a) { return util_iround(FIXED_ONE * a); } static INLINE float fixed_to_float(int a) { return a * (1.0f / FIXED_ONE); } /* Position and area in fixed point coordinates */ struct fixed_position { int x[4]; int y[4]; int area; int dx01; int dy01; int dx20; int dy20; }; /** * Alloc space for a new triangle plus the input.a0/dadx/dady arrays * immediately after it. * The memory is allocated from the per-scene pool, not per-tile. * \param tri_size returns number of bytes allocated * \param num_inputs number of fragment shader inputs * \return pointer to triangle space */ struct lp_rast_triangle * lp_setup_alloc_triangle(struct lp_scene *scene, unsigned nr_inputs, unsigned nr_planes, unsigned *tri_size) { unsigned input_array_sz = NUM_CHANNELS * (nr_inputs + 1) * sizeof(float); unsigned plane_sz = nr_planes * sizeof(struct lp_rast_plane); struct lp_rast_triangle *tri; *tri_size = (sizeof(struct lp_rast_triangle) + 3 * input_array_sz + plane_sz); tri = lp_scene_alloc_aligned( scene, *tri_size, 16 ); if (tri == NULL) return NULL; tri->inputs.stride = input_array_sz; { char *a = (char *)tri; char *b = (char *)&GET_PLANES(tri)[nr_planes]; assert(b - a == *tri_size); } return tri; } void lp_setup_print_vertex(struct lp_setup_context *setup, const char *name, const float (*v)[4]) { const struct lp_setup_variant_key *key = &setup->setup.variant->key; int i, j; debug_printf(" wpos (%s[0]) xyzw %f %f %f %f\n", name, v[0][0], v[0][1], v[0][2], v[0][3]); for (i = 0; i < key->num_inputs; i++) { const float *in = v[key->inputs[i].src_index]; debug_printf(" in[%d] (%s[%d]) %s%s%s%s ", i, name, key->inputs[i].src_index, (key->inputs[i].usage_mask & 0x1) ? "x" : " ", (key->inputs[i].usage_mask & 0x2) ? "y" : " ", (key->inputs[i].usage_mask & 0x4) ? "z" : " ", (key->inputs[i].usage_mask & 0x8) ? "w" : " "); for (j = 0; j < 4; j++) if (key->inputs[i].usage_mask & (1< 0.0f) debug_printf(" - cw\n"); else debug_printf(" - zero area\n"); } lp_setup_print_vertex(setup, "v0", v0); lp_setup_print_vertex(setup, "v1", v1); lp_setup_print_vertex(setup, "v2", v2); } #define MAX_PLANES 8 static unsigned lp_rast_tri_tab[MAX_PLANES+1] = { 0, /* should be impossible */ LP_RAST_OP_TRIANGLE_1, LP_RAST_OP_TRIANGLE_2, LP_RAST_OP_TRIANGLE_3, LP_RAST_OP_TRIANGLE_4, LP_RAST_OP_TRIANGLE_5, LP_RAST_OP_TRIANGLE_6, LP_RAST_OP_TRIANGLE_7, LP_RAST_OP_TRIANGLE_8 }; /** * The primitive covers the whole tile- shade whole tile. * * \param tx, ty the tile position in tiles, not pixels */ static boolean lp_setup_whole_tile(struct lp_setup_context *setup, const struct lp_rast_shader_inputs *inputs, int tx, int ty) { struct lp_scene *scene = setup->scene; LP_COUNT(nr_fully_covered_64); /* if variant is opaque and scissor doesn't effect the tile */ /* * Need to disable this optimization for layered rendering and cannot use * setup->layer_slot here to determine it, because it could incorrectly * reset the tile if a previous shader used layer_slot but not this one * (or maybe even "undo" clears). So determine this from presence of layers * instead (in which case layer_slot will have no effect). */ if (inputs->opaque && scene->fb_max_layer == 0) { if (!scene->fb.zsbuf) { /* * All previous rendering will be overwritten so reset the bin. * XXX This is wrong wrt to all queries arriving here (timestamp, * occlusion, ps invocations). Not counting stuff might be ok but it * will kill the begin/end query commands too which is definitely * wrong (and at this point we don't even know if there were any * such commands here). */ lp_scene_bin_reset( scene, tx, ty ); } LP_COUNT(nr_shade_opaque_64); return lp_scene_bin_cmd_with_state( scene, tx, ty, setup->fs.stored, LP_RAST_OP_SHADE_TILE_OPAQUE, lp_rast_arg_inputs(inputs) ); } else { LP_COUNT(nr_shade_64); return lp_scene_bin_cmd_with_state( scene, tx, ty, setup->fs.stored, LP_RAST_OP_SHADE_TILE, lp_rast_arg_inputs(inputs) ); } } /** * Do basic setup for triangle rasterization and determine which * framebuffer tiles are touched. Put the triangle in the scene's * bins for the tiles which we overlap. */ 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 ) { struct lp_scene *scene = setup->scene; const struct lp_setup_variant_key *key = &setup->setup.variant->key; struct lp_rast_triangle *tri; struct lp_rast_plane *plane; struct u_rect bbox; unsigned tri_bytes; int nr_planes = 3; unsigned scissor_index = 0; unsigned layer = 0; /* Area should always be positive here */ assert(position->area > 0); if (0) lp_setup_print_triangle(setup, v0, v1, v2); if (setup->scissor_test) { nr_planes = 7; if (setup->viewport_index_slot > 0) { unsigned *udata = (unsigned*)v0[setup->viewport_index_slot]; scissor_index = lp_clamp_scissor_idx(*udata); } } else { nr_planes = 3; } if (setup->layer_slot > 0) { layer = *(unsigned*)v1[setup->layer_slot]; layer = MIN2(layer, scene->fb_max_layer); } /* Bounding rectangle (in pixels) */ { /* Yes this is necessary to accurately calculate bounding boxes * with the two fill-conventions we support. GL (normally) ends * up needing a bottom-left fill convention, which requires * slightly different rounding. */ int adj = (setup->pixel_offset != 0) ? 1 : 0; /* Inclusive x0, exclusive x1 */ bbox.x0 = MIN3(position->x[0], position->x[1], position->x[2]) >> FIXED_ORDER; bbox.x1 = (MAX3(position->x[0], position->x[1], position->x[2]) - 1) >> FIXED_ORDER; /* Inclusive / exclusive depending upon adj (bottom-left or top-right) */ bbox.y0 = (MIN3(position->y[0], position->y[1], position->y[2]) + adj) >> FIXED_ORDER; bbox.y1 = (MAX3(position->y[0], position->y[1], position->y[2]) - 1 + adj) >> FIXED_ORDER; } if (bbox.x1 < bbox.x0 || bbox.y1 < bbox.y0) { if (0) debug_printf("empty bounding box\n"); LP_COUNT(nr_culled_tris); return TRUE; } if (!u_rect_test_intersection(&setup->draw_regions[scissor_index], &bbox)) { if (0) debug_printf("offscreen\n"); LP_COUNT(nr_culled_tris); return TRUE; } /* Can safely discard negative regions, but need to keep hold of * information about when the triangle extends past screen * boundaries. See trimmed_box in lp_setup_bin_triangle(). */ bbox.x0 = MAX2(bbox.x0, 0); bbox.y0 = MAX2(bbox.y0, 0); tri = lp_setup_alloc_triangle(scene, key->num_inputs, nr_planes, &tri_bytes); if (!tri) return FALSE; #if 0 tri->v[0][0] = v0[0][0]; tri->v[1][0] = v1[0][0]; tri->v[2][0] = v2[0][0]; tri->v[0][1] = v0[0][1]; tri->v[1][1] = v1[0][1]; tri->v[2][1] = v2[0][1]; #endif LP_COUNT(nr_tris); if (setup->active_query[PIPE_QUERY_PIPELINE_STATISTICS]) { struct llvmpipe_context *lp_context = (struct llvmpipe_context *)setup->pipe; lp_context->pipeline_statistics.c_primitives++; } /* Setup parameter interpolants: */ setup->setup.variant->jit_function( v0, v1, v2, frontfacing, GET_A0(&tri->inputs), GET_DADX(&tri->inputs), GET_DADY(&tri->inputs) ); tri->inputs.frontfacing = frontfacing; tri->inputs.disable = FALSE; tri->inputs.opaque = setup->fs.current.variant->opaque; tri->inputs.layer = layer; if (0) lp_dump_setup_coef(&setup->setup.variant->key, (const float (*)[4])GET_A0(&tri->inputs), (const float (*)[4])GET_DADX(&tri->inputs), (const float (*)[4])GET_DADY(&tri->inputs)); plane = GET_PLANES(tri); #if defined(PIPE_ARCH_SSE) { __m128i vertx, verty; __m128i shufx, shufy; __m128i dcdx, dcdy, c; __m128i unused; __m128i dcdx_neg_mask; __m128i dcdy_neg_mask; __m128i dcdx_zero_mask; __m128i top_left_flag; __m128i c_inc_mask, c_inc; __m128i eo, p0, p1, p2; __m128i zero = _mm_setzero_si128(); vertx = _mm_loadu_si128((__m128i *)position->x); /* vertex x coords */ verty = _mm_loadu_si128((__m128i *)position->y); /* vertex y coords */ shufx = _mm_shuffle_epi32(vertx, _MM_SHUFFLE(3,0,2,1)); shufy = _mm_shuffle_epi32(verty, _MM_SHUFFLE(3,0,2,1)); dcdx = _mm_sub_epi32(verty, shufy); dcdy = _mm_sub_epi32(vertx, shufx); dcdx_neg_mask = _mm_srai_epi32(dcdx, 31); dcdx_zero_mask = _mm_cmpeq_epi32(dcdx, zero); dcdy_neg_mask = _mm_srai_epi32(dcdy, 31); top_left_flag = _mm_set1_epi32((setup->bottom_edge_rule == 0) ? ~0 : 0); c_inc_mask = _mm_or_si128(dcdx_neg_mask, _mm_and_si128(dcdx_zero_mask, _mm_xor_si128(dcdy_neg_mask, top_left_flag))); c_inc = _mm_srli_epi32(c_inc_mask, 31); c = _mm_sub_epi32(mm_mullo_epi32(dcdx, vertx), mm_mullo_epi32(dcdy, verty)); c = _mm_add_epi32(c, c_inc); /* Scale up to match c: */ dcdx = _mm_slli_epi32(dcdx, FIXED_ORDER); dcdy = _mm_slli_epi32(dcdy, FIXED_ORDER); /* Calculate trivial reject values: */ eo = _mm_sub_epi32(_mm_andnot_si128(dcdy_neg_mask, dcdy), _mm_and_si128(dcdx_neg_mask, dcdx)); /* ei = _mm_sub_epi32(_mm_sub_epi32(dcdy, dcdx), eo); */ /* Pointless transpose which gets undone immediately in * rasterization: */ transpose4_epi32(&c, &dcdx, &dcdy, &eo, &p0, &p1, &p2, &unused); _mm_store_si128((__m128i *)&plane[0], p0); _mm_store_si128((__m128i *)&plane[1], p1); _mm_store_si128((__m128i *)&plane[2], p2); } #else { int i; plane[0].dcdy = position->dx01; plane[1].dcdy = position->x[1] - position->x[2]; plane[2].dcdy = position->dx20; plane[0].dcdx = position->dy01; plane[1].dcdx = position->y[1] - position->y[2]; plane[2].dcdx = position->dy20; for (i = 0; i < 3; i++) { /* half-edge constants, will be interated over the whole render * target. */ plane[i].c = plane[i].dcdx * position->x[i] - plane[i].dcdy * position->y[i]; /* correct for top-left vs. bottom-left fill convention. */ if (plane[i].dcdx < 0) { /* both fill conventions want this - adjust for left edges */ plane[i].c++; } else if (plane[i].dcdx == 0) { if (setup->bottom_edge_rule == 0){ /* correct for top-left fill convention: */ if (plane[i].dcdy > 0) plane[i].c++; } else { /* correct for bottom-left fill convention: */ if (plane[i].dcdy < 0) plane[i].c++; } } plane[i].dcdx *= FIXED_ONE; plane[i].dcdy *= FIXED_ONE; /* find trivial reject offsets for each edge for a single-pixel * sized block. These will be scaled up at each recursive level to * match the active blocksize. Scaling in this way works best if * the blocks are square. */ plane[i].eo = 0; if (plane[i].dcdx < 0) plane[i].eo -= plane[i].dcdx; if (plane[i].dcdy > 0) plane[i].eo += plane[i].dcdy; } } #endif if (0) { debug_printf("p0: %08x/%08x/%08x/%08x\n", plane[0].c, plane[0].dcdx, plane[0].dcdy, plane[0].eo); debug_printf("p1: %08x/%08x/%08x/%08x\n", plane[1].c, plane[1].dcdx, plane[1].dcdy, plane[1].eo); debug_printf("p0: %08x/%08x/%08x/%08x\n", plane[2].c, plane[2].dcdx, plane[2].dcdy, plane[2].eo); } /* * When rasterizing scissored tris, use the intersection of the * triangle bounding box and the scissor rect to generate the * scissor planes. * * This permits us to cut off the triangle "tails" that are present * in the intermediate recursive levels caused when two of the * triangles edges don't diverge quickly enough to trivially reject * exterior blocks from the triangle. * * It's not really clear if it's worth worrying about these tails, * but since we generate the planes for each scissored tri, it's * free to trim them in this case. * * Note that otherwise, the scissor planes only vary in 'C' value, * and even then only on state-changes. Could alternatively store * these planes elsewhere. */ if (nr_planes == 7) { const struct u_rect *scissor = &setup->scissors[scissor_index]; plane[3].dcdx = -1; plane[3].dcdy = 0; plane[3].c = 1-scissor->x0; plane[3].eo = 1; plane[4].dcdx = 1; plane[4].dcdy = 0; plane[4].c = scissor->x1+1; plane[4].eo = 0; plane[5].dcdx = 0; plane[5].dcdy = 1; plane[5].c = 1-scissor->y0; plane[5].eo = 1; plane[6].dcdx = 0; plane[6].dcdy = -1; plane[6].c = scissor->y1+1; plane[6].eo = 0; } return lp_setup_bin_triangle(setup, tri, &bbox, nr_planes, scissor_index); } /* * Round to nearest less or equal power of two of the input. * * Undefined if no bit set exists, so code should check against 0 first. */ static INLINE uint32_t floor_pot(uint32_t n) { #if defined(PIPE_CC_GCC) && defined(PIPE_ARCH_X86) if (n == 0) return 0; __asm__("bsr %1,%0" : "=r" (n) : "rm" (n)); return 1 << n; #else n |= (n >> 1); n |= (n >> 2); n |= (n >> 4); n |= (n >> 8); n |= (n >> 16); return n - (n >> 1); #endif } boolean lp_setup_bin_triangle( struct lp_setup_context *setup, struct lp_rast_triangle *tri, const struct u_rect *bbox, int nr_planes, unsigned scissor_index ) { struct lp_scene *scene = setup->scene; struct u_rect trimmed_box = *bbox; int i; /* What is the largest power-of-two boundary this triangle crosses: */ int dx = floor_pot((bbox->x0 ^ bbox->x1) | (bbox->y0 ^ bbox->y1)); /* The largest dimension of the rasterized area of the triangle * (aligned to a 4x4 grid), rounded down to the nearest power of two: */ int sz = floor_pot((bbox->x1 - (bbox->x0 & ~3)) | (bbox->y1 - (bbox->y0 & ~3))); /* Now apply scissor, etc to the bounding box. Could do this * earlier, but it confuses the logic for tri-16 and would force * the rasterizer to also respect scissor, etc, just for the rare * cases where a small triangle extends beyond the scissor. */ u_rect_find_intersection(&setup->draw_regions[scissor_index], &trimmed_box); /* Determine which tile(s) intersect the triangle's bounding box */ if (dx < TILE_SIZE) { int ix0 = bbox->x0 / TILE_SIZE; int iy0 = bbox->y0 / TILE_SIZE; unsigned px = bbox->x0 & 63 & ~3; unsigned py = bbox->y0 & 63 & ~3; assert(iy0 == bbox->y1 / TILE_SIZE && ix0 == bbox->x1 / TILE_SIZE); if (nr_planes == 3) { if (sz < 4) { /* Triangle is contained in a single 4x4 stamp: */ assert(px + 4 <= TILE_SIZE); assert(py + 4 <= TILE_SIZE); return lp_scene_bin_cmd_with_state( scene, ix0, iy0, setup->fs.stored, LP_RAST_OP_TRIANGLE_3_4, lp_rast_arg_triangle_contained(tri, px, py) ); } if (sz < 16) { /* Triangle is contained in a single 16x16 block: */ /* * The 16x16 block is only 4x4 aligned, and can exceed the tile * dimensions if the triangle is 16 pixels in one dimension but 4 * in the other. So budge the 16x16 back inside the tile. */ px = MIN2(px, TILE_SIZE - 16); py = MIN2(py, TILE_SIZE - 16); assert(px + 16 <= TILE_SIZE); assert(py + 16 <= TILE_SIZE); return lp_scene_bin_cmd_with_state( scene, ix0, iy0, setup->fs.stored, LP_RAST_OP_TRIANGLE_3_16, lp_rast_arg_triangle_contained(tri, px, py) ); } } else if (nr_planes == 4 && sz < 16) { px = MIN2(px, TILE_SIZE - 16); py = MIN2(py, TILE_SIZE - 16); assert(px + 16 <= TILE_SIZE); assert(py + 16 <= TILE_SIZE); return lp_scene_bin_cmd_with_state(scene, ix0, iy0, setup->fs.stored, LP_RAST_OP_TRIANGLE_4_16, lp_rast_arg_triangle_contained(tri, px, py)); } /* Triangle is contained in a single tile: */ return lp_scene_bin_cmd_with_state( scene, ix0, iy0, setup->fs.stored, lp_rast_tri_tab[nr_planes], lp_rast_arg_triangle(tri, (1<> 31); partial |= (planepartial >> 31) & (1<fs.stored, lp_rast_tri_tab[count], lp_rast_arg_triangle(tri, partial) )) goto fail; LP_COUNT(nr_partially_covered_64); } else { /* triangle covers the whole tile- shade whole tile */ LP_COUNT(nr_fully_covered_64); in = TRUE; if (!lp_setup_whole_tile(setup, &tri->inputs, x, y)) goto fail; } /* Iterate cx values across the region: */ for (i = 0; i < nr_planes; i++) cx[i] += xstep[i]; } /* Iterate c values down the region: */ for (i = 0; i < nr_planes; i++) c[i] += ystep[i]; } } return TRUE; fail: /* Need to disable any partially binned triangle. This is easier * than trying to locate all the triangle, shade-tile, etc, * commands which may have been binned. */ tri->inputs.disable = TRUE; return FALSE; } /** * Try to draw the triangle, restart the scene on failure. */ static void 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) { if (!do_triangle_ccw( setup, position, v0, v1, v2, front )) { if (!lp_setup_flush_and_restart(setup)) return; if (!do_triangle_ccw( setup, position, v0, v1, v2, front )) return; } } /** * Calculate fixed position data for a triangle */ 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]) { position->x[0] = subpixel_snap(v0[0][0] - setup->pixel_offset); position->x[1] = subpixel_snap(v1[0][0] - setup->pixel_offset); position->x[2] = subpixel_snap(v2[0][0] - setup->pixel_offset); position->x[3] = 0; position->y[0] = subpixel_snap(v0[0][1] - setup->pixel_offset); position->y[1] = subpixel_snap(v1[0][1] - setup->pixel_offset); position->y[2] = subpixel_snap(v2[0][1] - setup->pixel_offset); position->y[3] = 0; position->dx01 = position->x[0] - position->x[1]; position->dy01 = position->y[0] - position->y[1]; position->dx20 = position->x[2] - position->x[0]; position->dy20 = position->y[2] - position->y[0]; position->area = position->dx01 * position->dy20 - position->dx20 * position->dy01; } /** * Rotate a triangle, flipping its clockwise direction, * Swaps values for xy[0] and xy[1] */ static INLINE void rotate_fixed_position_01( struct fixed_position* position ) { int x, y; x = position->x[1]; y = position->y[1]; position->x[1] = position->x[0]; position->y[1] = position->y[0]; position->x[0] = x; position->y[0] = y; position->dx01 = -position->dx01; position->dy01 = -position->dy01; position->dx20 = position->x[2] - position->x[0]; position->dy20 = position->y[2] - position->y[0]; position->area = -position->area; } /** * Rotate a triangle, flipping its clockwise direction, * Swaps values for xy[1] and xy[2] */ static INLINE void rotate_fixed_position_12( struct fixed_position* position ) { int x, y; x = position->x[2]; y = position->y[2]; position->x[2] = position->x[1]; position->y[2] = position->y[1]; position->x[1] = x; position->y[1] = y; x = position->dx01; y = position->dy01; position->dx01 = -position->dx20; position->dy01 = -position->dy20; position->dx20 = -x; position->dy20 = -y; position->area = -position->area; } typedef void (*triangle_func_t)(struct lp_setup_context *setup, const float (*v0)[4], const float (*v1)[4], const float (*v2)[4]); /** * Subdivide this triangle by bisecting edge (v0, v1). * \param pv the provoking vertex (must = v0 or v1 or v2) * TODO: should probably think about non-overflowing arithmetic elsewhere. * This will definitely screw with pipeline counters for instance. */ static void subdiv_tri(struct lp_setup_context *setup, const float (*v0)[4], const float (*v1)[4], const float (*v2)[4], const float (*pv)[4], triangle_func_t tri) { unsigned n = setup->fs.current.variant->shader->info.base.num_inputs + 1; const struct lp_shader_input *inputs = setup->fs.current.variant->shader->inputs; float vmid[PIPE_MAX_ATTRIBS][4]; const float (*vm)[4] = (const float (*)[4]) vmid; unsigned i; float w0, w1, wm; boolean flatshade = setup->fs.current.variant->key.flatshade; /* find position midpoint (attrib[0] = position) */ vmid[0][0] = 0.5f * (v1[0][0] + v0[0][0]); vmid[0][1] = 0.5f * (v1[0][1] + v0[0][1]); vmid[0][2] = 0.5f * (v1[0][2] + v0[0][2]); vmid[0][3] = 0.5f * (v1[0][3] + v0[0][3]); w0 = v0[0][3]; w1 = v1[0][3]; wm = vmid[0][3]; /* interpolate other attributes */ for (i = 1; i < n; i++) { if ((inputs[i - 1].interp == LP_INTERP_COLOR && flatshade) || inputs[i - 1].interp == LP_INTERP_CONSTANT) { /* copy the provoking vertex's attribute */ vmid[i][0] = pv[i][0]; vmid[i][1] = pv[i][1]; vmid[i][2] = pv[i][2]; vmid[i][3] = pv[i][3]; } else { /* interpolate with perspective correction (for linear too) */ vmid[i][0] = 0.5f * (v1[i][0] * w1 + v0[i][0] * w0) / wm; vmid[i][1] = 0.5f * (v1[i][1] * w1 + v0[i][1] * w0) / wm; vmid[i][2] = 0.5f * (v1[i][2] * w1 + v0[i][2] * w0) / wm; vmid[i][3] = 0.5f * (v1[i][3] * w1 + v0[i][3] * w0) / wm; } } /* handling flat shading and first vs. last provoking vertex is a * little tricky... */ if (pv == v0) { if (setup->flatshade_first) { /* first vertex must be v0 or vm */ tri(setup, v0, vm, v2); tri(setup, vm, v1, v2); } else { /* last vertex must be v0 or vm */ tri(setup, vm, v2, v0); tri(setup, v1, v2, vm); } } else if (pv == v1) { if (setup->flatshade_first) { tri(setup, vm, v2, v0); tri(setup, v1, v2, vm); } else { tri(setup, v2, v0, vm); tri(setup, v2, vm, v1); } } else { if (setup->flatshade_first) { tri(setup, v2, v0, vm); tri(setup, v2, vm, v1); } else { tri(setup, v0, vm, v2); tri(setup, vm, v1, v2); } } } /** * Check the lengths of the edges of the triangle. If any edge is too * long, subdivide the longest edge and draw two sub-triangles. * Note: this may be called recursively. * \return TRUE if triangle was subdivided, FALSE otherwise */ static boolean check_subdivide_triangle(struct lp_setup_context *setup, const float (*v0)[4], const float (*v1)[4], const float (*v2)[4], triangle_func_t tri) { const float maxLen = 2048.0f; /* longest permissible edge, in pixels */ float dx10, dy10, len10; float dx21, dy21, len21; float dx02, dy02, len02; const float (*pv)[4] = setup->flatshade_first ? v0 : v2; /* compute lengths of triangle edges, squared */ dx10 = v1[0][0] - v0[0][0]; dy10 = v1[0][1] - v0[0][1]; len10 = dx10 * dx10 + dy10 * dy10; dx21 = v2[0][0] - v1[0][0]; dy21 = v2[0][1] - v1[0][1]; len21 = dx21 * dx21 + dy21 * dy21; dx02 = v0[0][0] - v2[0][0]; dy02 = v0[0][1] - v2[0][1]; len02 = dx02 * dx02 + dy02 * dy02; /* Look for longest the edge that's longer than maxLen. If we find * such an edge, split the triangle using the midpoint of that edge. * Note: it's important to split the longest edge, not just any edge * that's longer than maxLen. Otherwise, we can get into a degenerate * situation and recurse indefinitely. */ if (len10 > maxLen * maxLen && len10 >= len21 && len10 >= len02) { /* subdivide v0, v1 edge */ subdiv_tri(setup, v0, v1, v2, pv, tri); return TRUE; } if (len21 > maxLen * maxLen && len21 >= len10 && len21 >= len02) { /* subdivide v1, v2 edge */ subdiv_tri(setup, v1, v2, v0, pv, tri); return TRUE; } if (len02 > maxLen * maxLen && len02 >= len21 && len02 >= len10) { /* subdivide v2, v0 edge */ subdiv_tri(setup, v2, v0, v1, pv, tri); return TRUE; } return FALSE; } /** * Draw triangle if it's CW, cull otherwise. */ static void triangle_cw( struct lp_setup_context *setup, const float (*v0)[4], const float (*v1)[4], const float (*v2)[4] ) { struct fixed_position position; if (setup->subdivide_large_triangles && check_subdivide_triangle(setup, v0, v1, v2, triangle_cw)) return; calc_fixed_position(setup, &position, v0, v1, v2); if (position.area < 0) { if (setup->flatshade_first) { rotate_fixed_position_12(&position); retry_triangle_ccw(setup, &position, v0, v2, v1, !setup->ccw_is_frontface); } else { rotate_fixed_position_01(&position); retry_triangle_ccw(setup, &position, v1, v0, v2, !setup->ccw_is_frontface); } } } static void triangle_ccw( struct lp_setup_context *setup, const float (*v0)[4], const float (*v1)[4], const float (*v2)[4]) { struct fixed_position position; if (setup->subdivide_large_triangles && check_subdivide_triangle(setup, v0, v1, v2, triangle_ccw)) return; calc_fixed_position(setup, &position, v0, v1, v2); if (position.area > 0) retry_triangle_ccw(setup, &position, v0, v1, v2, setup->ccw_is_frontface); } /** * Draw triangle whether it's CW or CCW. */ static void triangle_both( struct lp_setup_context *setup, const float (*v0)[4], const float (*v1)[4], const float (*v2)[4] ) { struct fixed_position position; if (setup->subdivide_large_triangles && check_subdivide_triangle(setup, v0, v1, v2, triangle_both)) return; calc_fixed_position(setup, &position, v0, v1, v2); if (0) { assert(!util_is_inf_or_nan(v0[0][0])); assert(!util_is_inf_or_nan(v0[0][1])); assert(!util_is_inf_or_nan(v1[0][0])); assert(!util_is_inf_or_nan(v1[0][1])); assert(!util_is_inf_or_nan(v2[0][0])); assert(!util_is_inf_or_nan(v2[0][1])); } if (position.area > 0) retry_triangle_ccw( setup, &position, v0, v1, v2, setup->ccw_is_frontface ); else if (position.area < 0) { if (setup->flatshade_first) { rotate_fixed_position_12( &position ); retry_triangle_ccw( setup, &position, v0, v2, v1, !setup->ccw_is_frontface ); } else { rotate_fixed_position_01( &position ); retry_triangle_ccw( setup, &position, v1, v0, v2, !setup->ccw_is_frontface ); } } } static void triangle_nop( struct lp_setup_context *setup, const float (*v0)[4], const float (*v1)[4], const float (*v2)[4] ) { } void lp_setup_choose_triangle( struct lp_setup_context *setup ) { switch (setup->cullmode) { case PIPE_FACE_NONE: setup->triangle = triangle_both; break; case PIPE_FACE_BACK: setup->triangle = setup->ccw_is_frontface ? triangle_ccw : triangle_cw; break; case PIPE_FACE_FRONT: setup->triangle = setup->ccw_is_frontface ? triangle_cw : triangle_ccw; break; default: setup->triangle = triangle_nop; break; } }