From 5286dd701640976ffc328e8e85fb3830746851a1 Mon Sep 17 00:00:00 2001 From: Hui Qi Tay Date: Mon, 19 Jul 2010 15:23:09 +0100 Subject: llvmpipe: native rasterization for lines Rasterize lines directly by treating them as 4-sided polygons. Still need to check the exact pixel rasteration. --- src/gallium/drivers/llvmpipe/lp_setup_line.c | 617 ++++++++++++++++++++++++++- 1 file changed, 611 insertions(+), 6 deletions(-) (limited to 'src/gallium/drivers/llvmpipe/lp_setup_line.c') diff --git a/src/gallium/drivers/llvmpipe/lp_setup_line.c b/src/gallium/drivers/llvmpipe/lp_setup_line.c index be41c44e6f..930207ae33 100644 --- a/src/gallium/drivers/llvmpipe/lp_setup_line.c +++ b/src/gallium/drivers/llvmpipe/lp_setup_line.c @@ -29,19 +29,624 @@ * Binning code for lines */ +#include "util/u_math.h" +#include "util/u_memory.h" +#include "lp_perf.h" #include "lp_setup_context.h" +#include "lp_rast.h" +#include "lp_state_fs.h" -static void line_nop( struct lp_setup_context *setup, - const float (*v0)[4], - const float (*v1)[4] ) +#define NUM_CHANNELS 4 + + +static const int step_scissor_minx[16] = { + 0, 1, 0, 1, + 2, 3, 2, 3, + 0, 1, 0, 1, + 2, 3, 2, 3 +}; + +static const int step_scissor_maxx[16] = { + 0, -1, 0, -1, + -2, -3, -2, -3, + 0, -1, 0, -1, + -2, -3, -2, -3 +}; + +static const int step_scissor_miny[16] = { + 0, 0, 1, 1, + 0, 0, 1, 1, + 2, 2, 3, 3, + 2, 2, 3, 3 +}; + +static const int step_scissor_maxy[16] = { + 0, 0, -1, -1, + 0, 0, -1, -1, + -2, -2, -3, -3, + -2, -2, -3, -3 +}; + + + +/** + * Compute a0 for a constant-valued coefficient (GL_FLAT shading). + */ +static void constant_coef( struct lp_setup_context *setup, + struct lp_rast_triangle *tri, + unsigned slot, + const float value, + unsigned i ) +{ + tri->inputs.a0[slot][i] = value; + tri->inputs.dadx[slot][i] = 0.0f; + tri->inputs.dady[slot][i] = 0.0f; +} + + +/** + * Compute a0, dadx and dady for a linearly interpolated coefficient, + * for a triangle. + */ +static void linear_coef( struct lp_setup_context *setup, + struct lp_rast_triangle *tri, + float oneoverarea, + unsigned slot, + const float (*v1)[4], + const float (*v2)[4], + unsigned vert_attr, + unsigned i) +{ + float a1 = v1[vert_attr][i]; + float a2 = v2[vert_attr][i]; + + float da21 = a1 - a2; + float dadx = da21 * tri->dx * oneoverarea; + float dady = da21 * tri->dy * oneoverarea; + + tri->inputs.dadx[slot][i] = dadx; + tri->inputs.dady[slot][i] = dady; + + tri->inputs.a0[slot][i] = (a1 - + (dadx * (v1[0][0] - setup->pixel_offset) + + dady * (v1[0][1] - setup->pixel_offset))); +} + + +/** + * Compute a0, dadx and dady for a perspective-corrected interpolant, + * for a triangle. + * We basically multiply the vertex value by 1/w before computing + * the plane coefficients (a0, dadx, dady). + * Later, when we compute the value at a particular fragment position we'll + * divide the interpolated value by the interpolated W at that fragment. + */ +static void perspective_coef( struct lp_setup_context *setup, + struct lp_rast_triangle *tri, + float oneoverarea, + unsigned slot, + const float (*v1)[4], + const float (*v2)[4], + unsigned vert_attr, + unsigned i) +{ + /* premultiply by 1/w (v[0][3] is always 1/w): + */ + float a1 = v1[vert_attr][i] * v1[0][3]; + float a2 = v2[vert_attr][i] * v2[0][3]; + + float da21 = a1 - a2; + float dadx = da21 * tri->dx * oneoverarea; + float dady = da21 * tri->dy * oneoverarea; + + tri->inputs.dadx[slot][i] = dadx; + tri->inputs.dady[slot][i] = dady; + + tri->inputs.a0[slot][i] = (a1 - + (dadx * (v1[0][0] - setup->pixel_offset) + + dady * (v1[0][1] - setup->pixel_offset))); +} + +/** + * Compute the tri->coef[] array dadx, dady, a0 values. + */ +static void setup_line_coefficients( struct lp_setup_context *setup, + struct lp_rast_triangle *tri, + float oneoverarea, + const float (*v1)[4], + const float (*v2)[4]) { + unsigned fragcoord_usage_mask = TGSI_WRITEMASK_XYZ; + unsigned slot; + + /* setup interpolation for all the remaining attributes: + */ + for (slot = 0; slot < setup->fs.nr_inputs; slot++) { + unsigned vert_attr = setup->fs.input[slot].src_index; + unsigned usage_mask = setup->fs.input[slot].usage_mask; + unsigned i; + + switch (setup->fs.input[slot].interp) { + case LP_INTERP_CONSTANT: + if (setup->flatshade_first) { + for (i = 0; i < NUM_CHANNELS; i++) + if (usage_mask & (1 << i)) + constant_coef(setup, tri, slot+1, v1[vert_attr][i], i); + } + else { + for (i = 0; i < NUM_CHANNELS; i++) + if (usage_mask & (1 << i)) + constant_coef(setup, tri, slot+1, v2[vert_attr][i], i); + } + break; + + case LP_INTERP_LINEAR: + for (i = 0; i < NUM_CHANNELS; i++) + if (usage_mask & (1 << i)) + linear_coef(setup, tri, oneoverarea, slot+1, v1, v2, vert_attr, i); + break; + + case LP_INTERP_PERSPECTIVE: + for (i = 0; i < NUM_CHANNELS; i++) + if (usage_mask & (1 << i)) + perspective_coef(setup, tri, oneoverarea, slot+1, v1, v2, vert_attr, i); + fragcoord_usage_mask |= TGSI_WRITEMASK_W; + break; + + case LP_INTERP_POSITION: + /* + * The generated pixel interpolators will pick up the coeffs from + * slot 0, so all need to ensure that the usage mask is covers all + * usages. + */ + fragcoord_usage_mask |= usage_mask; + break; + + default: + assert(0); + } + } + + /* The internal position input is in slot zero: + */ + lp_setup_fragcoord_coef(setup, tri, oneoverarea, 0, v1, v2, v2, + fragcoord_usage_mask); } -void -lp_setup_choose_line( struct lp_setup_context *setup ) + +static INLINE int subpixel_snap( float a ) { - setup->line = line_nop; + return util_iround(FIXED_ONE * a); +} + + +/** + * Print line vertex attribs (for debug). + */ +static void +print_line(struct lp_setup_context *setup, + const float (*v1)[4], + const float (*v2)[4]) +{ + uint i; + + debug_printf("llvmpipe line\n"); + for (i = 0; i < 1 + setup->fs.nr_inputs; i++) { + debug_printf(" v1[%d]: %f %f %f %f\n", i, + v1[i][0], v1[i][1], v1[i][2], v1[i][3]); + } + for (i = 0; i < 1 + setup->fs.nr_inputs; i++) { + debug_printf(" v2[%d]: %f %f %f %f\n", i, + v2[i][0], v2[i][1], v2[i][2], v2[i][3]); + } +} + + +static void +lp_setup_line( struct lp_setup_context *setup, + const float (*v1)[4], + const float (*v2)[4]) +{ + struct lp_scene *scene = lp_setup_get_current_scene(setup); + struct lp_rast_triangle *line; + float oneoverarea; + float half_width = setup->line_width / 2; + int minx, maxx, miny, maxy; + int ix0, ix1, iy0, iy1; + unsigned tri_bytes; + int x[4]; + int y[4]; + int i; + int nr_planes = 4; + boolean opaque; + + if (0) + print_line(setup, v1, v2); + + if (setup->scissor_test) { + nr_planes = 8; + } + else { + nr_planes = 4; + } + + line = lp_setup_alloc_triangle(scene, + setup->fs.nr_inputs, + nr_planes, + &tri_bytes); + if (!line) + return; + +#ifndef DEBUG + line->v[0][0] = v1[0][0]; + line->v[1][0] = v2[0][0]; + line->v[0][1] = v1[0][1]; + line->v[1][1] = v2[0][1]; +#endif + + /* pre-calculation(based on given vertices) to determine if line is + * more horizontal or more vertical + */ + line->dx = v1[0][0] - v2[0][0]; + line->dy = v1[0][1] - v2[0][1]; + + /* x-major line */ + if (fabsf(line->dx) >= fabsf(line->dy)) { + if (line->dx < 0) { + /* if v2 is to the right of v1, swap pointers */ + const float (*temp)[4] = v1; + v1 = v2; + v2 = temp; + line->dx = -line->dx; + line->dy = -line->dy; + } + + /* x/y positions in fixed point */ + x[0] = subpixel_snap(v1[0][0] - setup->pixel_offset); + x[1] = subpixel_snap(v2[0][0] - setup->pixel_offset); + x[2] = subpixel_snap(v2[0][0] - setup->pixel_offset); + x[3] = subpixel_snap(v1[0][0] - setup->pixel_offset); + + y[0] = subpixel_snap(v1[0][1] - half_width - setup->pixel_offset); + y[1] = subpixel_snap(v2[0][1] - half_width - setup->pixel_offset); + y[2] = subpixel_snap(v2[0][1] + half_width - setup->pixel_offset); + y[3] = subpixel_snap(v1[0][1] + half_width - setup->pixel_offset); + } + else{ + /* y-major line */ + if (line->dy > 0) { + /* if v2 is on top of v1, swap pointers */ + const float (*temp)[4] = v1; + v1 = v2; + v2 = temp; + line->dx = -line->dx; + line->dy = -line->dy; + } + + x[0] = subpixel_snap(v1[0][0] - half_width - setup->pixel_offset); + x[1] = subpixel_snap(v2[0][0] - half_width - setup->pixel_offset); + x[2] = subpixel_snap(v2[0][0] + half_width - setup->pixel_offset); + x[3] = subpixel_snap(v1[0][0] + half_width - setup->pixel_offset); + + y[0] = subpixel_snap(v1[0][1] - setup->pixel_offset); + y[1] = subpixel_snap(v2[0][1] - setup->pixel_offset); + y[2] = subpixel_snap(v2[0][1] - setup->pixel_offset); + y[3] = subpixel_snap(v1[0][1] - setup->pixel_offset); + } + + /* calculate the deltas */ + line->plane[0].dcdy = x[0] - x[1]; + line->plane[1].dcdy = x[1] - x[2]; + line->plane[2].dcdy = x[2] - x[3]; + line->plane[3].dcdy = x[3] - x[0]; + + line->plane[0].dcdx = y[0] - y[1]; + line->plane[1].dcdx = y[1] - y[2]; + line->plane[2].dcdx = y[2] - y[3]; + line->plane[3].dcdx = y[3] - y[0]; + + + LP_COUNT(nr_tris); + + + /* 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; + + minx = (MIN4(x[0], x[1], x[2], x[3]) + (FIXED_ONE-1)) >> FIXED_ORDER; + maxx = (MAX4(x[0], x[1], x[2], x[3]) + (FIXED_ONE-1)) >> FIXED_ORDER; + miny = (MIN4(y[0], y[1], y[3], y[3]) + (FIXED_ONE-1) + adj) >> FIXED_ORDER; + maxy = (MAX4(y[0], y[1], y[3], y[3]) + (FIXED_ONE-1) + adj) >> FIXED_ORDER; + } + + if (setup->scissor_test) { + minx = MAX2(minx, setup->scissor.current.minx); + maxx = MIN2(maxx, setup->scissor.current.maxx); + miny = MAX2(miny, setup->scissor.current.miny); + maxy = MIN2(maxy, setup->scissor.current.maxy); + } + else { + minx = MAX2(minx, 0); + miny = MAX2(miny, 0); + maxx = MIN2(maxx, scene->fb.width); + maxy = MIN2(maxy, scene->fb.height); + } + + + if (miny >= maxy || minx >= maxx) { + lp_scene_putback_data( scene, tri_bytes ); + return; + } + + oneoverarea = 1.0f / (line->dx * line->dx + line->dy * line->dy); + + /* Setup parameter interpolants: + */ + setup_line_coefficients( setup, line, oneoverarea, v1, v2); + + for (i = 0; i < 4; i++) { + struct lp_rast_plane *plane = &line->plane[i]; + + /* half-edge constants, will be interated over the whole render + * target. + */ + plane->c = plane->dcdx * x[i] - plane->dcdy * y[i]; + + + /* correct for top-left vs. bottom-left fill convention. + * + * note that we're overloading gl_rasterization_rules to mean + * both (0.5,0.5) pixel centers *and* bottom-left filling + * convention. + * + * GL actually has a top-left filling convention, but GL's + * notion of "top" differs from gallium's... + * + * Also, sometimes (in FBO cases) GL will render upside down + * to its usual method, in which case it will probably want + * to use the opposite, top-left convention. + */ + if (plane->dcdx < 0) { + /* both fill conventions want this - adjust for left edges */ + plane->c++; + } + else if (plane->dcdx == 0) { + if (setup->pixel_offset == 0) { + /* correct for top-left fill convention: + */ + if (plane->dcdy > 0) plane->c++; + } + else { + /* correct for bottom-left fill convention: + */ + if (plane->dcdy < 0) plane->c++; + } + } + + plane->dcdx *= FIXED_ONE; + plane->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->eo = 0; + if (plane->dcdx < 0) plane->eo -= plane->dcdx; + if (plane->dcdy > 0) plane->eo += plane->dcdy; + + /* Calculate trivial accept offsets from the above. + */ + plane->ei = plane->dcdy - plane->dcdx - plane->eo; + + plane->step = line->step[i]; + + /* Fill in the inputs.step[][] arrays. + * We've manually unrolled some loops here. + */ +#define SETUP_STEP(j, x, y) \ + line->step[i][j] = y * plane->dcdy - x * plane->dcdx + + SETUP_STEP(0, 0, 0); + SETUP_STEP(1, 1, 0); + SETUP_STEP(2, 0, 1); + SETUP_STEP(3, 1, 1); + + SETUP_STEP(4, 2, 0); + SETUP_STEP(5, 3, 0); + SETUP_STEP(6, 2, 1); + SETUP_STEP(7, 3, 1); + + SETUP_STEP(8, 0, 2); + SETUP_STEP(9, 1, 2); + SETUP_STEP(10, 0, 3); + SETUP_STEP(11, 1, 3); + + SETUP_STEP(12, 2, 2); + SETUP_STEP(13, 3, 2); + SETUP_STEP(14, 2, 3); + SETUP_STEP(15, 3, 3); +#undef STEP + } + + + /* + * 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 == 8) { + line->plane[4].step = step_scissor_maxx; + line->plane[4].dcdx = 1; + line->plane[4].dcdy = 0; + line->plane[4].c = maxx; + line->plane[4].ei = -1; + line->plane[4].eo = 0; + + line->plane[5].step = step_scissor_miny; + line->plane[5].dcdx = 0; + line->plane[5].dcdy = 1; + line->plane[5].c = 1-miny; + line->plane[5].ei = 0; + line->plane[5].eo = 1; + + line->plane[6].step = step_scissor_maxy; + line->plane[6].dcdx = 0; + line->plane[6].dcdy = -1; + line->plane[6].c = maxy; + line->plane[6].ei = -1; + line->plane[6].eo = 0; + + line->plane[7].step = step_scissor_minx; + line->plane[7].dcdx = -1; + line->plane[7].dcdy = 0; + line->plane[7].c = 1-minx; + line->plane[7].ei = 0; + line->plane[7].eo = 1; + } + + + /* + * All fields of 'tri' are now set. The remaining code here is + * concerned with binning. + */ + + /* Convert to tile coordinates, and inclusive ranges: + */ + ix0 = minx / TILE_SIZE; + iy0 = miny / TILE_SIZE; + ix1 = (maxx-1) / TILE_SIZE; + iy1 = (maxy-1) / TILE_SIZE; + + /* + * Clamp to framebuffer size + */ + assert(ix0 == MAX2(ix0, 0)); + assert(iy0 == MAX2(iy0, 0)); + assert(ix1 == MIN2(ix1, scene->tiles_x - 1)); + assert(iy1 == MIN2(iy1, scene->tiles_y - 1)); + + /* Determine which tile(s) intersect the triangle's bounding box + */ + if (iy0 == iy1 && ix0 == ix1) + { + /* Triangle is contained in a single tile: + */ + lp_scene_bin_command( scene, ix0, iy0, + lp_rast_tri_tab[nr_planes], + lp_rast_arg_triangle(line, (1<plane[i].c + + line->plane[i].dcdy * iy0 * TILE_SIZE - + line->plane[i].dcdx * ix0 * TILE_SIZE); + + ei[i] = line->plane[i].ei << TILE_ORDER; + eo[i] = line->plane[i].eo << TILE_ORDER; + xstep[i] = -(line->plane[i].dcdx << TILE_ORDER); + ystep[i] = line->plane[i].dcdy << TILE_ORDER; + } + + + + /* Test tile-sized blocks against the triangle. + * Discard blocks fully outside the tri. If the block is fully + * contained inside the tri, bin an lp_rast_shade_tile command. + * Else, bin a lp_rast_triangle command. + */ + for (y = iy0; y <= iy1; y++) + { + boolean in = FALSE; /* are we inside the triangle? */ + int cx[8]; + + for (i = 0; i < nr_planes; i++) + cx[i] = c[i]; + + for (x = ix0; x <= ix1; x++) + { + int out = 0; + int partial = 0; + + for (i = 0; i < nr_planes; i++) { + int planeout = cx[i] + eo[i]; + int planepartial = cx[i] + ei[i] - 1; + out |= (planeout >> 31); + partial |= (planepartial >> 31) & (1<line = lp_setup_line; } -- cgit v1.2.3