/************************************************************************** * * 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. * **************************************************************************/ /** * \brief Primitive rasterization/rendering (points, lines, triangles) * * \author Keith Whitwell * \author Brian Paul */ #include "sp_context.h" #include "sp_quad.h" #include "sp_quad_pipe.h" #include "sp_setup.h" #include "sp_state.h" #include "draw/draw_context.h" #include "draw/draw_vertex.h" #include "pipe/p_shader_tokens.h" #include "util/u_math.h" #include "util/u_memory.h" #define DEBUG_VERTS 0 #define DEBUG_FRAGS 0 /** * Triangle edge info */ struct edge { float dx; /**< X(v1) - X(v0), used only during setup */ float dy; /**< Y(v1) - Y(v0), used only during setup */ float dxdy; /**< dx/dy */ float sx, sy; /**< first sample point coord */ int lines; /**< number of lines on this edge */ }; /** * Max number of quads (2x2 pixel blocks) to process per batch. * This can't be arbitrarily increased since we depend on some 32-bit * bitmasks (two bits per quad). */ #define MAX_QUADS 16 /** * Triangle setup info. * Also used for line drawing (taking some liberties). */ struct setup_context { struct softpipe_context *softpipe; /* Vertices are just an array of floats making up each attribute in * turn. Currently fixed at 4 floats, but should change in time. * Codegen will help cope with this. */ const float (*vmax)[4]; const float (*vmid)[4]; const float (*vmin)[4]; const float (*vprovoke)[4]; struct edge ebot; struct edge etop; struct edge emaj; float oneoverarea; int facing; float pixel_offset; struct quad_header quad[MAX_QUADS]; struct quad_header *quad_ptrs[MAX_QUADS]; unsigned count; struct tgsi_interp_coef coef[PIPE_MAX_SHADER_INPUTS]; struct tgsi_interp_coef posCoef; /* For Z, W */ struct { int left[2]; /**< [0] = row0, [1] = row1 */ int right[2]; int y; } span; #if DEBUG_FRAGS uint numFragsEmitted; /**< per primitive */ uint numFragsWritten; /**< per primitive */ #endif unsigned cull_face; /* which faces cull */ unsigned nr_vertex_attrs; }; /** * Clip setup->quad against the scissor/surface bounds. */ static INLINE void quad_clip(struct setup_context *setup, struct quad_header *quad) { const struct pipe_scissor_state *cliprect = &setup->softpipe->cliprect; const int minx = (int) cliprect->minx; const int maxx = (int) cliprect->maxx; const int miny = (int) cliprect->miny; const int maxy = (int) cliprect->maxy; if (quad->input.x0 >= maxx || quad->input.y0 >= maxy || quad->input.x0 + 1 < minx || quad->input.y0 + 1 < miny) { /* totally clipped */ quad->inout.mask = 0x0; return; } if (quad->input.x0 < minx) quad->inout.mask &= (MASK_BOTTOM_RIGHT | MASK_TOP_RIGHT); if (quad->input.y0 < miny) quad->inout.mask &= (MASK_BOTTOM_LEFT | MASK_BOTTOM_RIGHT); if (quad->input.x0 == maxx - 1) quad->inout.mask &= (MASK_BOTTOM_LEFT | MASK_TOP_LEFT); if (quad->input.y0 == maxy - 1) quad->inout.mask &= (MASK_TOP_LEFT | MASK_TOP_RIGHT); } /** * Emit a quad (pass to next stage) with clipping. */ static INLINE void clip_emit_quad(struct setup_context *setup, struct quad_header *quad) { quad_clip( setup, quad ); if (quad->inout.mask) { struct softpipe_context *sp = setup->softpipe; sp->quad.first->run( sp->quad.first, &quad, 1 ); } } /** * Given an X or Y coordinate, return the block/quad coordinate that it * belongs to. */ static INLINE int block(int x) { return x & ~(2-1); } static INLINE int block_x(int x) { return x & ~(16-1); } /** * Render a horizontal span of quads */ static void flush_spans(struct setup_context *setup) { const int step = MAX_QUADS; const int xleft0 = setup->span.left[0]; const int xleft1 = setup->span.left[1]; const int xright0 = setup->span.right[0]; const int xright1 = setup->span.right[1]; struct quad_stage *pipe = setup->softpipe->quad.first; const int minleft = block_x(MIN2(xleft0, xleft1)); const int maxright = MAX2(xright0, xright1); int x; /* process quads in horizontal chunks of 16 */ for (x = minleft; x < maxright; x += step) { unsigned skip_left0 = CLAMP(xleft0 - x, 0, step); unsigned skip_left1 = CLAMP(xleft1 - x, 0, step); unsigned skip_right0 = CLAMP(x + step - xright0, 0, step); unsigned skip_right1 = CLAMP(x + step - xright1, 0, step); unsigned lx = x; unsigned q = 0; unsigned skipmask_left0 = (1U << skip_left0) - 1U; unsigned skipmask_left1 = (1U << skip_left1) - 1U; /* These calculations fail when step == 32 and skip_right == 0. */ unsigned skipmask_right0 = ~0U << (unsigned)(step - skip_right0); unsigned skipmask_right1 = ~0U << (unsigned)(step - skip_right1); unsigned mask0 = ~skipmask_left0 & ~skipmask_right0; unsigned mask1 = ~skipmask_left1 & ~skipmask_right1; if (mask0 | mask1) { do { unsigned quadmask = (mask0 & 3) | ((mask1 & 3) << 2); if (quadmask) { setup->quad[q].input.x0 = lx; setup->quad[q].input.y0 = setup->span.y; setup->quad[q].input.facing = setup->facing; setup->quad[q].inout.mask = quadmask; setup->quad_ptrs[q] = &setup->quad[q]; q++; } mask0 >>= 2; mask1 >>= 2; lx += 2; } while (mask0 | mask1); pipe->run( pipe, setup->quad_ptrs, q ); } } setup->span.y = 0; setup->span.right[0] = 0; setup->span.right[1] = 0; setup->span.left[0] = 1000000; /* greater than right[0] */ setup->span.left[1] = 1000000; /* greater than right[1] */ } #if DEBUG_VERTS static void print_vertex(const struct setup_context *setup, const float (*v)[4]) { int i; debug_printf(" Vertex: (%p)\n", (void *) v); for (i = 0; i < setup->nr_vertex_attrs; i++) { debug_printf(" %d: %f %f %f %f\n", i, v[i][0], v[i][1], v[i][2], v[i][3]); if (util_is_inf_or_nan(v[i][0])) { debug_printf(" NaN!\n"); } } } #endif /** * Sort the vertices from top to bottom order, setting up the triangle * edge fields (ebot, emaj, etop). * \return FALSE if coords are inf/nan (cull the tri), TRUE otherwise */ static boolean setup_sort_vertices(struct setup_context *setup, float det, const float (*v0)[4], const float (*v1)[4], const float (*v2)[4]) { if (setup->softpipe->rasterizer->flatshade_first) setup->vprovoke = v0; else setup->vprovoke = v2; /* determine bottom to top order of vertices */ { float y0 = v0[0][1]; float y1 = v1[0][1]; float y2 = v2[0][1]; if (y0 <= y1) { if (y1 <= y2) { /* y0<=y1<=y2 */ setup->vmin = v0; setup->vmid = v1; setup->vmax = v2; } else if (y2 <= y0) { /* y2<=y0<=y1 */ setup->vmin = v2; setup->vmid = v0; setup->vmax = v1; } else { /* y0<=y2<=y1 */ setup->vmin = v0; setup->vmid = v2; setup->vmax = v1; } } else { if (y0 <= y2) { /* y1<=y0<=y2 */ setup->vmin = v1; setup->vmid = v0; setup->vmax = v2; } else if (y2 <= y1) { /* y2<=y1<=y0 */ setup->vmin = v2; setup->vmid = v1; setup->vmax = v0; } else { /* y1<=y2<=y0 */ setup->vmin = v1; setup->vmid = v2; setup->vmax = v0; } } } setup->ebot.dx = setup->vmid[0][0] - setup->vmin[0][0]; setup->ebot.dy = setup->vmid[0][1] - setup->vmin[0][1]; setup->emaj.dx = setup->vmax[0][0] - setup->vmin[0][0]; setup->emaj.dy = setup->vmax[0][1] - setup->vmin[0][1]; setup->etop.dx = setup->vmax[0][0] - setup->vmid[0][0]; setup->etop.dy = setup->vmax[0][1] - setup->vmid[0][1]; /* * Compute triangle's area. Use 1/area to compute partial * derivatives of attributes later. * * The area will be the same as prim->det, but the sign may be * different depending on how the vertices get sorted above. * * To determine whether the primitive is front or back facing we * use the prim->det value because its sign is correct. */ { const float area = (setup->emaj.dx * setup->ebot.dy - setup->ebot.dx * setup->emaj.dy); setup->oneoverarea = 1.0f / area; /* debug_printf("%s one-over-area %f area %f det %f\n", __FUNCTION__, setup->oneoverarea, area, det ); */ if (util_is_inf_or_nan(setup->oneoverarea)) return FALSE; } /* We need to know if this is a front or back-facing triangle for: * - the GLSL gl_FrontFacing fragment attribute (bool) * - two-sided stencil test * 0 = front-facing, 1 = back-facing */ setup->facing = ((det < 0.0) ^ (setup->softpipe->rasterizer->front_ccw)); { unsigned face = setup->facing == 0 ? PIPE_FACE_FRONT : PIPE_FACE_BACK; if (face & setup->cull_face) return FALSE; } /* Prepare pixel offset for rasterisation: * - pixel center (0.5, 0.5) for GL, or * - assume (0.0, 0.0) for other APIs. */ if (setup->softpipe->rasterizer->gl_rasterization_rules) { setup->pixel_offset = 0.5f; } else { setup->pixel_offset = 0.0f; } return TRUE; } /* Apply cylindrical wrapping to v0, v1, v2 coordinates, if enabled. * Input coordinates must be in [0, 1] range, otherwise results are undefined. * Some combinations of coordinates produce invalid results, * but this behaviour is acceptable. */ static void tri_apply_cylindrical_wrap(float v0, float v1, float v2, uint cylindrical_wrap, float output[3]) { if (cylindrical_wrap) { float delta; delta = v1 - v0; if (delta > 0.5f) { v0 += 1.0f; } else if (delta < -0.5f) { v1 += 1.0f; } delta = v2 - v1; if (delta > 0.5f) { v1 += 1.0f; } else if (delta < -0.5f) { v2 += 1.0f; } delta = v0 - v2; if (delta > 0.5f) { v2 += 1.0f; } else if (delta < -0.5f) { v0 += 1.0f; } } output[0] = v0; output[1] = v1; output[2] = v2; } /** * Compute a0 for a constant-valued coefficient (GL_FLAT shading). * The value value comes from vertex[slot][i]. * The result will be put into setup->coef[slot].a0[i]. * \param slot which attribute slot * \param i which component of the slot (0..3) */ static void const_coeff(struct setup_context *setup, struct tgsi_interp_coef *coef, uint vertSlot, uint i) { assert(i <= 3); coef->dadx[i] = 0; coef->dady[i] = 0; /* need provoking vertex info! */ coef->a0[i] = setup->vprovoke[vertSlot][i]; } /** * Compute a0, dadx and dady for a linearly interpolated coefficient, * for a triangle. * v[0], v[1] and v[2] are vmin, vmid and vmax, respectively. */ static void tri_linear_coeff(struct setup_context *setup, struct tgsi_interp_coef *coef, uint i, const float v[3]) { float botda = v[1] - v[0]; float majda = v[2] - v[0]; float a = setup->ebot.dy * majda - botda * setup->emaj.dy; float b = setup->emaj.dx * botda - majda * setup->ebot.dx; float dadx = a * setup->oneoverarea; float dady = b * setup->oneoverarea; assert(i <= 3); coef->dadx[i] = dadx; coef->dady[i] = dady; /* calculate a0 as the value which would be sampled for the * fragment at (0,0), taking into account that we want to sample at * pixel centers, in other words (pixel_offset, pixel_offset). * * this is neat but unfortunately not a good way to do things for * triangles with very large values of dadx or dady as it will * result in the subtraction and re-addition from a0 of a very * large number, which means we'll end up loosing a lot of the * fractional bits and precision from a0. the way to fix this is * to define a0 as the sample at a pixel center somewhere near vmin * instead - i'll switch to this later. */ coef->a0[i] = (v[0] - (dadx * (setup->vmin[0][0] - setup->pixel_offset) + dady * (setup->vmin[0][1] - setup->pixel_offset))); /* debug_printf("attr[%d].%c: %f dx:%f dy:%f\n", slot, "xyzw"[i], setup->coef[slot].a0[i], setup->coef[slot].dadx[i], setup->coef[slot].dady[i]); */ } /** * 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. * v[0], v[1] and v[2] are vmin, vmid and vmax, respectively. */ static void tri_persp_coeff(struct setup_context *setup, struct tgsi_interp_coef *coef, uint i, const float v[3]) { /* premultiply by 1/w (v[0][3] is always W): */ float mina = v[0] * setup->vmin[0][3]; float mida = v[1] * setup->vmid[0][3]; float maxa = v[2] * setup->vmax[0][3]; float botda = mida - mina; float majda = maxa - mina; float a = setup->ebot.dy * majda - botda * setup->emaj.dy; float b = setup->emaj.dx * botda - majda * setup->ebot.dx; float dadx = a * setup->oneoverarea; float dady = b * setup->oneoverarea; /* debug_printf("tri persp %d,%d: %f %f %f\n", vertSlot, i, setup->vmin[vertSlot][i], setup->vmid[vertSlot][i], setup->vmax[vertSlot][i] ); */ assert(i <= 3); coef->dadx[i] = dadx; coef->dady[i] = dady; coef->a0[i] = (mina - (dadx * (setup->vmin[0][0] - setup->pixel_offset) + dady * (setup->vmin[0][1] - setup->pixel_offset))); } /** * Special coefficient setup for gl_FragCoord. * X and Y are trivial, though Y may have to be inverted for OpenGL. * Z and W are copied from posCoef which should have already been computed. * We could do a bit less work if we'd examine gl_FragCoord's swizzle mask. */ static void setup_fragcoord_coeff(struct setup_context *setup, uint slot) { const struct tgsi_shader_info *fsInfo = &setup->softpipe->fs_variant->info; /*X*/ setup->coef[slot].a0[0] = fsInfo->pixel_center_integer ? 0.0 : 0.5; setup->coef[slot].dadx[0] = 1.0; setup->coef[slot].dady[0] = 0.0; /*Y*/ setup->coef[slot].a0[1] = (fsInfo->origin_lower_left ? setup->softpipe->framebuffer.height-1 : 0) + (fsInfo->pixel_center_integer ? 0.0 : 0.5); setup->coef[slot].dadx[1] = 0.0; setup->coef[slot].dady[1] = fsInfo->origin_lower_left ? -1.0 : 1.0; /*Z*/ setup->coef[slot].a0[2] = setup->posCoef.a0[2]; setup->coef[slot].dadx[2] = setup->posCoef.dadx[2]; setup->coef[slot].dady[2] = setup->posCoef.dady[2]; /*W*/ setup->coef[slot].a0[3] = setup->posCoef.a0[3]; setup->coef[slot].dadx[3] = setup->posCoef.dadx[3]; setup->coef[slot].dady[3] = setup->posCoef.dady[3]; } /** * Compute the setup->coef[] array dadx, dady, a0 values. * Must be called after setup->vmin,vmid,vmax,vprovoke are initialized. */ static void setup_tri_coefficients(struct setup_context *setup) { struct softpipe_context *softpipe = setup->softpipe; const struct tgsi_shader_info *fsInfo = &setup->softpipe->fs_variant->info; const struct vertex_info *vinfo = softpipe_get_vertex_info(softpipe); uint fragSlot; float v[3]; /* z and w are done by linear interpolation: */ v[0] = setup->vmin[0][2]; v[1] = setup->vmid[0][2]; v[2] = setup->vmax[0][2]; tri_linear_coeff(setup, &setup->posCoef, 2, v); v[0] = setup->vmin[0][3]; v[1] = setup->vmid[0][3]; v[2] = setup->vmax[0][3]; tri_linear_coeff(setup, &setup->posCoef, 3, v); /* setup interpolation for all the remaining attributes: */ for (fragSlot = 0; fragSlot < fsInfo->num_inputs; fragSlot++) { const uint vertSlot = vinfo->attrib[fragSlot].src_index; uint j; switch (vinfo->attrib[fragSlot].interp_mode) { case INTERP_CONSTANT: for (j = 0; j < TGSI_NUM_CHANNELS; j++) const_coeff(setup, &setup->coef[fragSlot], vertSlot, j); break; case INTERP_LINEAR: for (j = 0; j < TGSI_NUM_CHANNELS; j++) { tri_apply_cylindrical_wrap(setup->vmin[vertSlot][j], setup->vmid[vertSlot][j], setup->vmax[vertSlot][j], fsInfo->input_cylindrical_wrap[fragSlot] & (1 << j), v); tri_linear_coeff(setup, &setup->coef[fragSlot], j, v); } break; case INTERP_PERSPECTIVE: for (j = 0; j < TGSI_NUM_CHANNELS; j++) { tri_apply_cylindrical_wrap(setup->vmin[vertSlot][j], setup->vmid[vertSlot][j], setup->vmax[vertSlot][j], fsInfo->input_cylindrical_wrap[fragSlot] & (1 << j), v); tri_persp_coeff(setup, &setup->coef[fragSlot], j, v); } break; case INTERP_POS: setup_fragcoord_coeff(setup, fragSlot); break; default: assert(0); } if (fsInfo->input_semantic_name[fragSlot] == TGSI_SEMANTIC_FACE) { /* convert 0 to 1.0 and 1 to -1.0 */ setup->coef[fragSlot].a0[0] = setup->facing * -2.0f + 1.0f; setup->coef[fragSlot].dadx[0] = 0.0; setup->coef[fragSlot].dady[0] = 0.0; } } } static void setup_tri_edges(struct setup_context *setup) { float vmin_x = setup->vmin[0][0] + setup->pixel_offset; float vmid_x = setup->vmid[0][0] + setup->pixel_offset; float vmin_y = setup->vmin[0][1] - setup->pixel_offset; float vmid_y = setup->vmid[0][1] - setup->pixel_offset; float vmax_y = setup->vmax[0][1] - setup->pixel_offset; setup->emaj.sy = ceilf(vmin_y); setup->emaj.lines = (int) ceilf(vmax_y - setup->emaj.sy); setup->emaj.dxdy = setup->emaj.dy ? setup->emaj.dx / setup->emaj.dy : .0f; setup->emaj.sx = vmin_x + (setup->emaj.sy - vmin_y) * setup->emaj.dxdy; setup->etop.sy = ceilf(vmid_y); setup->etop.lines = (int) ceilf(vmax_y - setup->etop.sy); setup->etop.dxdy = setup->etop.dy ? setup->etop.dx / setup->etop.dy : .0f; setup->etop.sx = vmid_x + (setup->etop.sy - vmid_y) * setup->etop.dxdy; setup->ebot.sy = ceilf(vmin_y); setup->ebot.lines = (int) ceilf(vmid_y - setup->ebot.sy); setup->ebot.dxdy = setup->ebot.dy ? setup->ebot.dx / setup->ebot.dy : .0f; setup->ebot.sx = vmin_x + (setup->ebot.sy - vmin_y) * setup->ebot.dxdy; } /** * Render the upper or lower half of a triangle. * Scissoring/cliprect is applied here too. */ static void subtriangle(struct setup_context *setup, struct edge *eleft, struct edge *eright, int lines) { const struct pipe_scissor_state *cliprect = &setup->softpipe->cliprect; const int minx = (int) cliprect->minx; const int maxx = (int) cliprect->maxx; const int miny = (int) cliprect->miny; const int maxy = (int) cliprect->maxy; int y, start_y, finish_y; int sy = (int)eleft->sy; assert((int)eleft->sy == (int) eright->sy); assert(lines >= 0); /* clip top/bottom */ start_y = sy; if (start_y < miny) start_y = miny; finish_y = sy + lines; if (finish_y > maxy) finish_y = maxy; start_y -= sy; finish_y -= sy; /* debug_printf("%s %d %d\n", __FUNCTION__, start_y, finish_y); */ for (y = start_y; y < finish_y; y++) { /* avoid accumulating adds as floats don't have the precision to * accurately iterate large triangle edges that way. luckily we * can just multiply these days. * * this is all drowned out by the attribute interpolation anyway. */ int left = (int)(eleft->sx + y * eleft->dxdy); int right = (int)(eright->sx + y * eright->dxdy); /* clip left/right */ if (left < minx) left = minx; if (right > maxx) right = maxx; if (left < right) { int _y = sy + y; if (block(_y) != setup->span.y) { flush_spans(setup); setup->span.y = block(_y); } setup->span.left[_y&1] = left; setup->span.right[_y&1] = right; } } /* save the values so that emaj can be restarted: */ eleft->sx += lines * eleft->dxdy; eright->sx += lines * eright->dxdy; eleft->sy += lines; eright->sy += lines; } /** * Recalculate prim's determinant. This is needed as we don't have * get this information through the vbuf_render interface & we must * calculate it here. */ static float calc_det(const float (*v0)[4], const float (*v1)[4], const float (*v2)[4]) { /* edge vectors e = v0 - v2, f = v1 - v2 */ const float ex = v0[0][0] - v2[0][0]; const float ey = v0[0][1] - v2[0][1]; const float fx = v1[0][0] - v2[0][0]; const float fy = v1[0][1] - v2[0][1]; /* det = cross(e,f).z */ return ex * fy - ey * fx; } /** * Do setup for triangle rasterization, then render the triangle. */ void sp_setup_tri(struct setup_context *setup, const float (*v0)[4], const float (*v1)[4], const float (*v2)[4]) { float det; #if DEBUG_VERTS debug_printf("Setup triangle:\n"); print_vertex(setup, v0); print_vertex(setup, v1); print_vertex(setup, v2); #endif if (setup->softpipe->no_rast || setup->softpipe->rasterizer->rasterizer_discard) return; det = calc_det(v0, v1, v2); /* debug_printf("%s\n", __FUNCTION__ ); */ #if DEBUG_FRAGS setup->numFragsEmitted = 0; setup->numFragsWritten = 0; #endif if (!setup_sort_vertices( setup, det, v0, v1, v2 )) return; setup_tri_coefficients( setup ); setup_tri_edges( setup ); assert(setup->softpipe->reduced_prim == PIPE_PRIM_TRIANGLES); setup->span.y = 0; setup->span.right[0] = 0; setup->span.right[1] = 0; /* setup->span.z_mode = tri_z_mode( setup->ctx ); */ /* init_constant_attribs( setup ); */ if (setup->oneoverarea < 0.0) { /* emaj on left: */ subtriangle( setup, &setup->emaj, &setup->ebot, setup->ebot.lines ); subtriangle( setup, &setup->emaj, &setup->etop, setup->etop.lines ); } else { /* emaj on right: */ subtriangle( setup, &setup->ebot, &setup->emaj, setup->ebot.lines ); subtriangle( setup, &setup->etop, &setup->emaj, setup->etop.lines ); } flush_spans( setup ); #if DEBUG_FRAGS printf("Tri: %u frags emitted, %u written\n", setup->numFragsEmitted, setup->numFragsWritten); #endif } /* Apply cylindrical wrapping to v0, v1 coordinates, if enabled. * Input coordinates must be in [0, 1] range, otherwise results are undefined. */ static void line_apply_cylindrical_wrap(float v0, float v1, uint cylindrical_wrap, float output[2]) { if (cylindrical_wrap) { float delta; delta = v1 - v0; if (delta > 0.5f) { v0 += 1.0f; } else if (delta < -0.5f) { v1 += 1.0f; } } output[0] = v0; output[1] = v1; } /** * Compute a0, dadx and dady for a linearly interpolated coefficient, * for a line. * v[0] and v[1] are vmin and vmax, respectively. */ static void line_linear_coeff(const struct setup_context *setup, struct tgsi_interp_coef *coef, uint i, const float v[2]) { const float da = v[1] - v[0]; const float dadx = da * setup->emaj.dx * setup->oneoverarea; const float dady = da * setup->emaj.dy * setup->oneoverarea; coef->dadx[i] = dadx; coef->dady[i] = dady; coef->a0[i] = (v[0] - (dadx * (setup->vmin[0][0] - setup->pixel_offset) + dady * (setup->vmin[0][1] - setup->pixel_offset))); } /** * Compute a0, dadx and dady for a perspective-corrected interpolant, * for a line. * v[0] and v[1] are vmin and vmax, respectively. */ static void line_persp_coeff(const struct setup_context *setup, struct tgsi_interp_coef *coef, uint i, const float v[2]) { const float a0 = v[0] * setup->vmin[0][3]; const float a1 = v[1] * setup->vmax[0][3]; const float da = a1 - a0; const float dadx = da * setup->emaj.dx * setup->oneoverarea; const float dady = da * setup->emaj.dy * setup->oneoverarea; coef->dadx[i] = dadx; coef->dady[i] = dady; coef->a0[i] = (a0 - (dadx * (setup->vmin[0][0] - setup->pixel_offset) + dady * (setup->vmin[0][1] - setup->pixel_offset))); } /** * Compute the setup->coef[] array dadx, dady, a0 values. * Must be called after setup->vmin,vmax are initialized. */ static boolean setup_line_coefficients(struct setup_context *setup, const float (*v0)[4], const float (*v1)[4]) { struct softpipe_context *softpipe = setup->softpipe; const struct tgsi_shader_info *fsInfo = &setup->softpipe->fs_variant->info; const struct vertex_info *vinfo = softpipe_get_vertex_info(softpipe); uint fragSlot; float area; float v[2]; /* use setup->vmin, vmax to point to vertices */ if (softpipe->rasterizer->flatshade_first) setup->vprovoke = v0; else setup->vprovoke = v1; setup->vmin = v0; setup->vmax = v1; setup->emaj.dx = setup->vmax[0][0] - setup->vmin[0][0]; setup->emaj.dy = setup->vmax[0][1] - setup->vmin[0][1]; /* NOTE: this is not really area but something proportional to it */ area = setup->emaj.dx * setup->emaj.dx + setup->emaj.dy * setup->emaj.dy; if (area == 0.0f || util_is_inf_or_nan(area)) return FALSE; setup->oneoverarea = 1.0f / area; /* z and w are done by linear interpolation: */ v[0] = setup->vmin[0][2]; v[1] = setup->vmax[0][2]; line_linear_coeff(setup, &setup->posCoef, 2, v); v[0] = setup->vmin[0][3]; v[1] = setup->vmax[0][3]; line_linear_coeff(setup, &setup->posCoef, 3, v); /* setup interpolation for all the remaining attributes: */ for (fragSlot = 0; fragSlot < fsInfo->num_inputs; fragSlot++) { const uint vertSlot = vinfo->attrib[fragSlot].src_index; uint j; switch (vinfo->attrib[fragSlot].interp_mode) { case INTERP_CONSTANT: for (j = 0; j < TGSI_NUM_CHANNELS; j++) const_coeff(setup, &setup->coef[fragSlot], vertSlot, j); break; case INTERP_LINEAR: for (j = 0; j < TGSI_NUM_CHANNELS; j++) { line_apply_cylindrical_wrap(setup->vmin[vertSlot][j], setup->vmax[vertSlot][j], fsInfo->input_cylindrical_wrap[fragSlot] & (1 << j), v); line_linear_coeff(setup, &setup->coef[fragSlot], j, v); } break; case INTERP_PERSPECTIVE: for (j = 0; j < TGSI_NUM_CHANNELS; j++) { line_apply_cylindrical_wrap(setup->vmin[vertSlot][j], setup->vmax[vertSlot][j], fsInfo->input_cylindrical_wrap[fragSlot] & (1 << j), v); line_persp_coeff(setup, &setup->coef[fragSlot], j, v); } break; case INTERP_POS: setup_fragcoord_coeff(setup, fragSlot); break; default: assert(0); } if (fsInfo->input_semantic_name[fragSlot] == TGSI_SEMANTIC_FACE) { /* convert 0 to 1.0 and 1 to -1.0 */ setup->coef[fragSlot].a0[0] = setup->facing * -2.0f + 1.0f; setup->coef[fragSlot].dadx[0] = 0.0; setup->coef[fragSlot].dady[0] = 0.0; } } return TRUE; } /** * Plot a pixel in a line segment. */ static INLINE void plot(struct setup_context *setup, int x, int y) { const int iy = y & 1; const int ix = x & 1; const int quadX = x - ix; const int quadY = y - iy; const int mask = (1 << ix) << (2 * iy); if (quadX != setup->quad[0].input.x0 || quadY != setup->quad[0].input.y0) { /* flush prev quad, start new quad */ if (setup->quad[0].input.x0 != -1) clip_emit_quad( setup, &setup->quad[0] ); setup->quad[0].input.x0 = quadX; setup->quad[0].input.y0 = quadY; setup->quad[0].inout.mask = 0x0; } setup->quad[0].inout.mask |= mask; } /** * Do setup for line rasterization, then render the line. * Single-pixel width, no stipple, etc. We rely on the 'draw' module * to handle stippling and wide lines. */ void sp_setup_line(struct setup_context *setup, const float (*v0)[4], const float (*v1)[4]) { int x0 = (int) v0[0][0]; int x1 = (int) v1[0][0]; int y0 = (int) v0[0][1]; int y1 = (int) v1[0][1]; int dx = x1 - x0; int dy = y1 - y0; int xstep, ystep; #if DEBUG_VERTS debug_printf("Setup line:\n"); print_vertex(setup, v0); print_vertex(setup, v1); #endif if (setup->softpipe->no_rast || setup->softpipe->rasterizer->rasterizer_discard) return; if (dx == 0 && dy == 0) return; if (!setup_line_coefficients(setup, v0, v1)) return; assert(v0[0][0] < 1.0e9); assert(v0[0][1] < 1.0e9); assert(v1[0][0] < 1.0e9); assert(v1[0][1] < 1.0e9); if (dx < 0) { dx = -dx; /* make positive */ xstep = -1; } else { xstep = 1; } if (dy < 0) { dy = -dy; /* make positive */ ystep = -1; } else { ystep = 1; } assert(dx >= 0); assert(dy >= 0); assert(setup->softpipe->reduced_prim == PIPE_PRIM_LINES); setup->quad[0].input.x0 = setup->quad[0].input.y0 = -1; setup->quad[0].inout.mask = 0x0; /* XXX temporary: set coverage to 1.0 so the line appears * if AA mode happens to be enabled. */ setup->quad[0].input.coverage[0] = setup->quad[0].input.coverage[1] = setup->quad[0].input.coverage[2] = setup->quad[0].input.coverage[3] = 1.0; if (dx > dy) { /*** X-major line ***/ int i; const int errorInc = dy + dy; int error = errorInc - dx; const int errorDec = error - dx; for (i = 0; i < dx; i++) { plot(setup, x0, y0); x0 += xstep; if (error < 0) { error += errorInc; } else { error += errorDec; y0 += ystep; } } } else { /*** Y-major line ***/ int i; const int errorInc = dx + dx; int error = errorInc - dy; const int errorDec = error - dy; for (i = 0; i < dy; i++) { plot(setup, x0, y0); y0 += ystep; if (error < 0) { error += errorInc; } else { error += errorDec; x0 += xstep; } } } /* draw final quad */ if (setup->quad[0].inout.mask) { clip_emit_quad( setup, &setup->quad[0] ); } } static void point_persp_coeff(const struct setup_context *setup, const float (*vert)[4], struct tgsi_interp_coef *coef, uint vertSlot, uint i) { assert(i <= 3); coef->dadx[i] = 0.0F; coef->dady[i] = 0.0F; coef->a0[i] = vert[vertSlot][i] * vert[0][3]; } /** * Do setup for point rasterization, then render the point. * Round or square points... * XXX could optimize a lot for 1-pixel points. */ void sp_setup_point(struct setup_context *setup, const float (*v0)[4]) { struct softpipe_context *softpipe = setup->softpipe; const struct tgsi_shader_info *fsInfo = &setup->softpipe->fs_variant->info; const int sizeAttr = setup->softpipe->psize_slot; const float size = sizeAttr > 0 ? v0[sizeAttr][0] : setup->softpipe->rasterizer->point_size; const float halfSize = 0.5F * size; const boolean round = (boolean) setup->softpipe->rasterizer->point_smooth; const float x = v0[0][0]; /* Note: data[0] is always position */ const float y = v0[0][1]; const struct vertex_info *vinfo = softpipe_get_vertex_info(softpipe); uint fragSlot; #if DEBUG_VERTS debug_printf("Setup point:\n"); print_vertex(setup, v0); #endif if (setup->softpipe->no_rast || setup->softpipe->rasterizer->rasterizer_discard) return; assert(setup->softpipe->reduced_prim == PIPE_PRIM_POINTS); /* For points, all interpolants are constant-valued. * However, for point sprites, we'll need to setup texcoords appropriately. * XXX: which coefficients are the texcoords??? * We may do point sprites as textured quads... * * KW: We don't know which coefficients are texcoords - ultimately * the choice of what interpolation mode to use for each attribute * should be determined by the fragment program, using * per-attribute declaration statements that include interpolation * mode as a parameter. So either the fragment program will have * to be adjusted for pointsprite vs normal point behaviour, or * otherwise a special interpolation mode will have to be defined * which matches the required behaviour for point sprites. But - * the latter is not a feature of normal hardware, and as such * probably should be ruled out on that basis. */ setup->vprovoke = v0; /* setup Z, W */ const_coeff(setup, &setup->posCoef, 0, 2); const_coeff(setup, &setup->posCoef, 0, 3); for (fragSlot = 0; fragSlot < fsInfo->num_inputs; fragSlot++) { const uint vertSlot = vinfo->attrib[fragSlot].src_index; uint j; switch (vinfo->attrib[fragSlot].interp_mode) { case INTERP_CONSTANT: /* fall-through */ case INTERP_LINEAR: for (j = 0; j < TGSI_NUM_CHANNELS; j++) const_coeff(setup, &setup->coef[fragSlot], vertSlot, j); break; case INTERP_PERSPECTIVE: for (j = 0; j < TGSI_NUM_CHANNELS; j++) point_persp_coeff(setup, setup->vprovoke, &setup->coef[fragSlot], vertSlot, j); break; case INTERP_POS: setup_fragcoord_coeff(setup, fragSlot); break; default: assert(0); } if (fsInfo->input_semantic_name[fragSlot] == TGSI_SEMANTIC_FACE) { /* convert 0 to 1.0 and 1 to -1.0 */ setup->coef[fragSlot].a0[0] = setup->facing * -2.0f + 1.0f; setup->coef[fragSlot].dadx[0] = 0.0; setup->coef[fragSlot].dady[0] = 0.0; } } if (halfSize <= 0.5 && !round) { /* special case for 1-pixel points */ const int ix = ((int) x) & 1; const int iy = ((int) y) & 1; setup->quad[0].input.x0 = (int) x - ix; setup->quad[0].input.y0 = (int) y - iy; setup->quad[0].inout.mask = (1 << ix) << (2 * iy); clip_emit_quad( setup, &setup->quad[0] ); } else { if (round) { /* rounded points */ const int ixmin = block((int) (x - halfSize)); const int ixmax = block((int) (x + halfSize)); const int iymin = block((int) (y - halfSize)); const int iymax = block((int) (y + halfSize)); const float rmin = halfSize - 0.7071F; /* 0.7071 = sqrt(2)/2 */ const float rmax = halfSize + 0.7071F; const float rmin2 = MAX2(0.0F, rmin * rmin); const float rmax2 = rmax * rmax; const float cscale = 1.0F / (rmax2 - rmin2); int ix, iy; for (iy = iymin; iy <= iymax; iy += 2) { for (ix = ixmin; ix <= ixmax; ix += 2) { float dx, dy, dist2, cover; setup->quad[0].inout.mask = 0x0; dx = (ix + 0.5f) - x; dy = (iy + 0.5f) - y; dist2 = dx * dx + dy * dy; if (dist2 <= rmax2) { cover = 1.0F - (dist2 - rmin2) * cscale; setup->quad[0].input.coverage[QUAD_TOP_LEFT] = MIN2(cover, 1.0f); setup->quad[0].inout.mask |= MASK_TOP_LEFT; } dx = (ix + 1.5f) - x; dy = (iy + 0.5f) - y; dist2 = dx * dx + dy * dy; if (dist2 <= rmax2) { cover = 1.0F - (dist2 - rmin2) * cscale; setup->quad[0].input.coverage[QUAD_TOP_RIGHT] = MIN2(cover, 1.0f); setup->quad[0].inout.mask |= MASK_TOP_RIGHT; } dx = (ix + 0.5f) - x; dy = (iy + 1.5f) - y; dist2 = dx * dx + dy * dy; if (dist2 <= rmax2) { cover = 1.0F - (dist2 - rmin2) * cscale; setup->quad[0].input.coverage[QUAD_BOTTOM_LEFT] = MIN2(cover, 1.0f); setup->quad[0].inout.mask |= MASK_BOTTOM_LEFT; } dx = (ix + 1.5f) - x; dy = (iy + 1.5f) - y; dist2 = dx * dx + dy * dy; if (dist2 <= rmax2) { cover = 1.0F - (dist2 - rmin2) * cscale; setup->quad[0].input.coverage[QUAD_BOTTOM_RIGHT] = MIN2(cover, 1.0f); setup->quad[0].inout.mask |= MASK_BOTTOM_RIGHT; } if (setup->quad[0].inout.mask) { setup->quad[0].input.x0 = ix; setup->quad[0].input.y0 = iy; clip_emit_quad( setup, &setup->quad[0] ); } } } } else { /* square points */ const int xmin = (int) (x + 0.75 - halfSize); const int ymin = (int) (y + 0.25 - halfSize); const int xmax = xmin + (int) size; const int ymax = ymin + (int) size; /* XXX could apply scissor to xmin,ymin,xmax,ymax now */ const int ixmin = block(xmin); const int ixmax = block(xmax - 1); const int iymin = block(ymin); const int iymax = block(ymax - 1); int ix, iy; /* debug_printf("(%f, %f) -> X:%d..%d Y:%d..%d\n", x, y, xmin, xmax,ymin,ymax); */ for (iy = iymin; iy <= iymax; iy += 2) { uint rowMask = 0xf; if (iy < ymin) { /* above the top edge */ rowMask &= (MASK_BOTTOM_LEFT | MASK_BOTTOM_RIGHT); } if (iy + 1 >= ymax) { /* below the bottom edge */ rowMask &= (MASK_TOP_LEFT | MASK_TOP_RIGHT); } for (ix = ixmin; ix <= ixmax; ix += 2) { uint mask = rowMask; if (ix < xmin) { /* fragment is past left edge of point, turn off left bits */ mask &= (MASK_BOTTOM_RIGHT | MASK_TOP_RIGHT); } if (ix + 1 >= xmax) { /* past the right edge */ mask &= (MASK_BOTTOM_LEFT | MASK_TOP_LEFT); } setup->quad[0].inout.mask = mask; setup->quad[0].input.x0 = ix; setup->quad[0].input.y0 = iy; clip_emit_quad( setup, &setup->quad[0] ); } } } } } /** * Called by vbuf code just before we start buffering primitives. */ void sp_setup_prepare(struct setup_context *setup) { struct softpipe_context *sp = setup->softpipe; if (sp->dirty) { softpipe_update_derived(sp, sp->reduced_api_prim); } /* Note: nr_attrs is only used for debugging (vertex printing) */ setup->nr_vertex_attrs = draw_num_shader_outputs(sp->draw); sp->quad.first->begin( sp->quad.first ); if (sp->reduced_api_prim == PIPE_PRIM_TRIANGLES && sp->rasterizer->fill_front == PIPE_POLYGON_MODE_FILL && sp->rasterizer->fill_back == PIPE_POLYGON_MODE_FILL) { /* we'll do culling */ setup->cull_face = sp->rasterizer->cull_face; } else { /* 'draw' will do culling */ setup->cull_face = PIPE_FACE_NONE; } } void sp_setup_destroy_context(struct setup_context *setup) { FREE( setup ); } /** * Create a new primitive setup/render stage. */ struct setup_context * sp_setup_create_context(struct softpipe_context *softpipe) { struct setup_context *setup = CALLOC_STRUCT(setup_context); unsigned i; setup->softpipe = softpipe; for (i = 0; i < MAX_QUADS; i++) { setup->quad[i].coef = setup->coef; setup->quad[i].posCoef = &setup->posCoef; } setup->span.left[0] = 1000000; /* greater than right[0] */ setup->span.left[1] = 1000000; /* greater than right[1] */ return setup; }