/************************************************************************** * * 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 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" #include "lp_state_setup.h" #define NUM_CHANNELS 4 struct lp_line_info { float dx; float dy; float oneoverarea; const float (*v1)[4]; const float (*v2)[4]; float (*a0)[4]; float (*dadx)[4]; float (*dady)[4]; }; /** * Compute a0 for a constant-valued coefficient (GL_FLAT shading). */ static void constant_coef( struct lp_setup_context *setup, struct lp_line_info *info, unsigned slot, const float value, unsigned i ) { info->a0[slot][i] = value; info->dadx[slot][i] = 0.0f; info->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_line_info *info, unsigned slot, unsigned vert_attr, unsigned i) { float a1 = info->v1[vert_attr][i]; float a2 = info->v2[vert_attr][i]; float da21 = a1 - a2; float dadx = da21 * info->dx * info->oneoverarea; float dady = da21 * info->dy * info->oneoverarea; info->dadx[slot][i] = dadx; info->dady[slot][i] = dady; info->a0[slot][i] = (a1 - (dadx * (info->v1[0][0] - setup->pixel_offset) + dady * (info->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_line_info *info, unsigned slot, unsigned vert_attr, unsigned i) { /* premultiply by 1/w (v[0][3] is always 1/w): */ float a1 = info->v1[vert_attr][i] * info->v1[0][3]; float a2 = info->v2[vert_attr][i] * info->v2[0][3]; float da21 = a1 - a2; float dadx = da21 * info->dx * info->oneoverarea; float dady = da21 * info->dy * info->oneoverarea; info->dadx[slot][i] = dadx; info->dady[slot][i] = dady; info->a0[slot][i] = (a1 - (dadx * (info->v1[0][0] - setup->pixel_offset) + dady * (info->v1[0][1] - setup->pixel_offset))); } static void setup_fragcoord_coef( struct lp_setup_context *setup, struct lp_line_info *info, unsigned slot, unsigned usage_mask) { /*X*/ if (usage_mask & TGSI_WRITEMASK_X) { info->a0[slot][0] = 0.0; info->dadx[slot][0] = 1.0; info->dady[slot][0] = 0.0; } /*Y*/ if (usage_mask & TGSI_WRITEMASK_Y) { info->a0[slot][1] = 0.0; info->dadx[slot][1] = 0.0; info->dady[slot][1] = 1.0; } /*Z*/ if (usage_mask & TGSI_WRITEMASK_Z) { linear_coef(setup, info, slot, 0, 2); } /*W*/ if (usage_mask & TGSI_WRITEMASK_W) { linear_coef(setup, info, slot, 0, 3); } } /** * Compute the tri->coef[] array dadx, dady, a0 values. */ static void setup_line_coefficients( struct lp_setup_context *setup, struct lp_line_info *info) { const struct lp_setup_variant_key *key = &setup->setup.variant->key; unsigned fragcoord_usage_mask = TGSI_WRITEMASK_XYZ; unsigned slot; /* setup interpolation for all the remaining attributes: */ for (slot = 0; slot < key->num_inputs; slot++) { unsigned vert_attr = key->inputs[slot].src_index; unsigned usage_mask = key->inputs[slot].usage_mask; unsigned i; switch (key->inputs[slot].interp) { case LP_INTERP_CONSTANT: if (key->flatshade_first) { for (i = 0; i < NUM_CHANNELS; i++) if (usage_mask & (1 << i)) constant_coef(setup, info, slot+1, info->v1[vert_attr][i], i); } else { for (i = 0; i < NUM_CHANNELS; i++) if (usage_mask & (1 << i)) constant_coef(setup, info, slot+1, info->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, info, slot+1, vert_attr, i); break; case LP_INTERP_PERSPECTIVE: for (i = 0; i < NUM_CHANNELS; i++) if (usage_mask & (1 << i)) perspective_coef(setup, info, slot+1, 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; case LP_INTERP_FACING: for (i = 0; i < NUM_CHANNELS; i++) if (usage_mask & (1 << i)) constant_coef(setup, info, slot+1, 1.0, i); break; default: assert(0); } } /* The internal position input is in slot zero: */ setup_fragcoord_coef(setup, info, 0, fragcoord_usage_mask); } static INLINE int subpixel_snap( float a ) { 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]) { const struct lp_setup_variant_key *key = &setup->setup.variant->key; uint i; debug_printf("llvmpipe line\n"); for (i = 0; i < 1 + key->num_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 + key->num_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 INLINE boolean sign(float x){ return x >= 0; } /* Used on positive floats only: */ static INLINE float fracf(float f) { return f - floorf(f); } static boolean try_setup_line( struct lp_setup_context *setup, const float (*v1)[4], const float (*v2)[4]) { struct lp_scene *scene = setup->scene; const struct lp_setup_variant_key *key = &setup->setup.variant->key; struct lp_rast_triangle *line; struct lp_rast_plane *plane; struct lp_line_info info; float width = MAX2(1.0, setup->line_width); struct u_rect bbox; unsigned tri_bytes; int x[4]; int y[4]; int i; int nr_planes = 4; unsigned scissor_index = 0; /* linewidth should be interpreted as integer */ int fixed_width = util_iround(width) * FIXED_ONE; float x_offset=0; float y_offset=0; float x_offset_end=0; float y_offset_end=0; float x1diff; float y1diff; float x2diff; float y2diff; float dx, dy; float area; boolean draw_start; boolean draw_end; boolean will_draw_start; boolean will_draw_end; if (0) print_line(setup, v1, v2); if (setup->scissor_test) { nr_planes = 8; if (setup->viewport_index_slot > 0) { unsigned *udata = (unsigned*)v1[setup->viewport_index_slot]; scissor_index = lp_clamp_scissor_idx(*udata); } } else { nr_planes = 4; } dx = v1[0][0] - v2[0][0]; dy = v1[0][1] - v2[0][1]; area = (dx * dx + dy * dy); if (area == 0) { LP_COUNT(nr_culled_tris); return TRUE; } info.oneoverarea = 1.0f / area; info.dx = dx; info.dy = dy; info.v1 = v1; info.v2 = v2; /* X-MAJOR LINE */ if (fabsf(dx) >= fabsf(dy)) { float dydx = dy / dx; x1diff = v1[0][0] - (float) floor(v1[0][0]) - 0.5; y1diff = v1[0][1] - (float) floor(v1[0][1]) - 0.5; x2diff = v2[0][0] - (float) floor(v2[0][0]) - 0.5; y2diff = v2[0][1] - (float) floor(v2[0][1]) - 0.5; if (y2diff==-0.5 && dy<0){ y2diff = 0.5; } /* * Diamond exit rule test for starting point */ if (fabsf(x1diff) + fabsf(y1diff) < 0.5) { draw_start = TRUE; } else if (sign(x1diff) == sign(-dx)) { draw_start = FALSE; } else if (sign(-y1diff) != sign(dy)) { draw_start = TRUE; } else { /* do intersection test */ float yintersect = fracf(v1[0][1]) + x1diff * dydx; draw_start = (yintersect < 1.0 && yintersect > 0.0); } /* * Diamond exit rule test for ending point */ if (fabsf(x2diff) + fabsf(y2diff) < 0.5) { draw_end = FALSE; } else if (sign(x2diff) != sign(-dx)) { draw_end = FALSE; } else if (sign(-y2diff) == sign(dy)) { draw_end = TRUE; } else { /* do intersection test */ float yintersect = fracf(v2[0][1]) + x2diff * dydx; draw_end = (yintersect < 1.0 && yintersect > 0.0); } /* Are we already drawing start/end? */ will_draw_start = sign(-x1diff) != sign(dx); will_draw_end = (sign(x2diff) == sign(-dx)) || x2diff==0; if (dx < 0) { /* if v2 is to the right of v1, swap pointers */ const float (*temp)[4] = v1; v1 = v2; v2 = temp; dx = -dx; dy = -dy; /* Otherwise shift planes appropriately */ if (will_draw_start != draw_start) { x_offset_end = - x1diff - 0.5; y_offset_end = x_offset_end * dydx; } if (will_draw_end != draw_end) { x_offset = - x2diff - 0.5; y_offset = x_offset * dydx; } } else{ /* Otherwise shift planes appropriately */ if (will_draw_start != draw_start) { x_offset = - x1diff + 0.5; y_offset = x_offset * dydx; } if (will_draw_end != draw_end) { x_offset_end = - x2diff + 0.5; y_offset_end = x_offset_end * dydx; } } /* x/y positions in fixed point */ x[0] = subpixel_snap(v1[0][0] + x_offset - setup->pixel_offset); x[1] = subpixel_snap(v2[0][0] + x_offset_end - setup->pixel_offset); x[2] = subpixel_snap(v2[0][0] + x_offset_end - setup->pixel_offset); x[3] = subpixel_snap(v1[0][0] + x_offset - setup->pixel_offset); y[0] = subpixel_snap(v1[0][1] + y_offset - setup->pixel_offset) - fixed_width/2; y[1] = subpixel_snap(v2[0][1] + y_offset_end - setup->pixel_offset) - fixed_width/2; y[2] = subpixel_snap(v2[0][1] + y_offset_end - setup->pixel_offset) + fixed_width/2; y[3] = subpixel_snap(v1[0][1] + y_offset - setup->pixel_offset) + fixed_width/2; } else { const float dxdy = dx / dy; /* Y-MAJOR LINE */ x1diff = v1[0][0] - (float) floor(v1[0][0]) - 0.5; y1diff = v1[0][1] - (float) floor(v1[0][1]) - 0.5; x2diff = v2[0][0] - (float) floor(v2[0][0]) - 0.5; y2diff = v2[0][1] - (float) floor(v2[0][1]) - 0.5; if (x2diff==-0.5 && dx<0) { x2diff = 0.5; } /* * Diamond exit rule test for starting point */ if (fabsf(x1diff) + fabsf(y1diff) < 0.5) { draw_start = TRUE; } else if (sign(-y1diff) == sign(dy)) { draw_start = FALSE; } else if (sign(x1diff) != sign(-dx)) { draw_start = TRUE; } else { /* do intersection test */ float xintersect = fracf(v1[0][0]) + y1diff * dxdy; draw_start = (xintersect < 1.0 && xintersect > 0.0); } /* * Diamond exit rule test for ending point */ if (fabsf(x2diff) + fabsf(y2diff) < 0.5) { draw_end = FALSE; } else if (sign(-y2diff) != sign(dy) ) { draw_end = FALSE; } else if (sign(x2diff) == sign(-dx) ) { draw_end = TRUE; } else { /* do intersection test */ float xintersect = fracf(v2[0][0]) + y2diff * dxdy; draw_end = (xintersect < 1.0 && xintersect >= 0.0); } /* Are we already drawing start/end? */ will_draw_start = sign(y1diff) == sign(dy); will_draw_end = (sign(-y2diff) == sign(dy)) || y2diff==0; if (dy > 0) { /* if v2 is on top of v1, swap pointers */ const float (*temp)[4] = v1; v1 = v2; v2 = temp; dx = -dx; dy = -dy; /* Otherwise shift planes appropriately */ if (will_draw_start != draw_start) { y_offset_end = - y1diff + 0.5; x_offset_end = y_offset_end * dxdy; } if (will_draw_end != draw_end) { y_offset = - y2diff + 0.5; x_offset = y_offset * dxdy; } } else { /* Otherwise shift planes appropriately */ if (will_draw_start != draw_start) { y_offset = - y1diff - 0.5; x_offset = y_offset * dxdy; } if (will_draw_end != draw_end) { y_offset_end = - y2diff - 0.5; x_offset_end = y_offset_end * dxdy; } } /* x/y positions in fixed point */ x[0] = subpixel_snap(v1[0][0] + x_offset - setup->pixel_offset) - fixed_width/2; x[1] = subpixel_snap(v2[0][0] + x_offset_end - setup->pixel_offset) - fixed_width/2; x[2] = subpixel_snap(v2[0][0] + x_offset_end - setup->pixel_offset) + fixed_width/2; x[3] = subpixel_snap(v1[0][0] + x_offset - setup->pixel_offset) + fixed_width/2; y[0] = subpixel_snap(v1[0][1] + y_offset - setup->pixel_offset); y[1] = subpixel_snap(v2[0][1] + y_offset_end - setup->pixel_offset); y[2] = subpixel_snap(v2[0][1] + y_offset_end - setup->pixel_offset); y[3] = subpixel_snap(v1[0][1] + y_offset - setup->pixel_offset); } 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; bbox.x0 = (MIN4(x[0], x[1], x[2], x[3]) + (FIXED_ONE-1)) >> FIXED_ORDER; bbox.x1 = (MAX4(x[0], x[1], x[2], x[3]) + (FIXED_ONE-1)) >> FIXED_ORDER; bbox.y0 = (MIN4(y[0], y[1], y[2], y[3]) + (FIXED_ONE-1) + adj) >> FIXED_ORDER; bbox.y1 = (MAX4(y[0], y[1], y[2], y[3]) + (FIXED_ONE-1) + adj) >> FIXED_ORDER; /* Inclusive coordinates: */ bbox.x1--; bbox.y1--; } 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: */ bbox.x0 = MAX2(bbox.x0, 0); bbox.y0 = MAX2(bbox.y0, 0); line = lp_setup_alloc_triangle(scene, key->num_inputs, nr_planes, &tri_bytes); if (!line) return FALSE; #ifdef 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 /* calculate the deltas */ plane = GET_PLANES(line); plane[0].dcdy = x[0] - x[1]; plane[1].dcdy = x[1] - x[2]; plane[2].dcdy = x[2] - x[3]; plane[3].dcdy = x[3] - x[0]; plane[0].dcdx = y[0] - y[1]; plane[1].dcdx = y[1] - y[2]; plane[2].dcdx = y[2] - y[3]; plane[3].dcdx = y[3] - y[0]; /* Setup parameter interpolants: */ info.a0 = GET_A0(&line->inputs); info.dadx = GET_DADX(&line->inputs); info.dady = GET_DADY(&line->inputs); setup_line_coefficients(setup, &info); line->inputs.frontfacing = TRUE; line->inputs.disable = FALSE; line->inputs.opaque = FALSE; for (i = 0; i < 4; i++) { /* half-edge constants, will be interated over the whole render * target. */ plane[i].c = plane[i].dcdx * x[i] - plane[i].dcdy * 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->pixel_offset == 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; } /* * 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) { const struct u_rect *scissor = &setup->scissors[scissor_index]; plane[4].dcdx = -1; plane[4].dcdy = 0; plane[4].c = 1-scissor->x0; plane[4].eo = 1; plane[5].dcdx = 1; plane[5].dcdy = 0; plane[5].c = scissor->x1+1; plane[5].eo = 0; plane[6].dcdx = 0; plane[6].dcdy = 1; plane[6].c = 1-scissor->y0; plane[6].eo = 1; plane[7].dcdx = 0; plane[7].dcdy = -1; plane[7].c = scissor->y1+1; plane[7].eo = 0; } return lp_setup_bin_triangle(setup, line, &bbox, nr_planes, scissor_index); } static void lp_setup_line( struct lp_setup_context *setup, const float (*v0)[4], const float (*v1)[4] ) { if (!try_setup_line( setup, v0, v1 )) { if (!lp_setup_flush_and_restart(setup)) return; if (!try_setup_line( setup, v0, v1 )) return; } } void lp_setup_choose_line( struct lp_setup_context *setup ) { setup->line = lp_setup_line; }