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diff --git a/src/mesa/pipe/softpipe/g_prim_setup.c b/src/mesa/pipe/softpipe/g_prim_setup.c
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-/**************************************************************************
- *
- * 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.
- *
- **************************************************************************/
-
-/* Authors: Keith Whitwell <keith@tungstengraphics.com>
- */
-
-#include "imports.h"
-#include "macros.h"
-
-#include "g_context.h"
-#include "g_prim.h"
-#include "g_tile.h"
-
-
-/**
- * Triangle edge info
- */
-struct edge {
- GLfloat dx; /* X(v1) - X(v0), used only during setup */
- GLfloat dy; /* Y(v1) - Y(v0), used only during setup */
- GLfloat dxdy; /* dx/dy */
- GLfloat sx; /* first sample point x coord */
- GLfloat sy;
- GLint lines; /* number of lines on this edge */
-};
-
-
-/**
- * Triangle setup info (derived from prim_stage).
- * Also used for line drawing (taking some liberties).
- */
-struct setup_stage {
- struct prim_stage stage; /**< This must be first */
-
- /* 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 struct vertex_header *vmax;
- const struct vertex_header *vmid;
- const struct vertex_header *vmin;
- const struct vertex_header *vprovoke;
-
- struct edge ebot;
- struct edge etop;
- struct edge emaj;
-
- GLfloat oneoverarea;
-
- struct setup_coefficient coef[FRAG_ATTRIB_MAX];
- struct quad_header quad;
-
- struct {
- GLint left[2]; /**< [0] = row0, [1] = row1 */
- GLint right[2];
- GLint y;
- GLuint y_flags;
- GLuint mask; /**< mask of MASK_BOTTOM/TOP_LEFT/RIGHT bits */
- } span;
-};
-
-
-
-/**
- * Basically a cast wrapper.
- */
-static inline struct setup_stage *setup_stage( struct prim_stage *stage )
-{
- return (struct setup_stage *)stage;
-}
-
-
-/**
- * Given an X or Y coordinate, return the block/quad coordinate that it
- * belongs to.
- */
-static inline GLint block( GLint x )
-{
- return x & ~1;
-}
-
-
-
-static void setup_begin( struct prim_stage *stage )
-{
- setup_stage(stage)->quad.nr_attrs = stage->generic->nr_frag_attrs;
-}
-
-
-/**
- * Run shader on a quad/block.
- */
-static void run_shader_block( struct setup_stage *setup,
- GLint x, GLint y, GLuint mask )
-{
- setup->quad.x0 = x;
- setup->quad.y0 = y;
- setup->quad.mask = mask;
-
- quad_shade( setup->stage.generic, &setup->quad );
-}
-
-
-/**
- * Compute mask which indicates which pixels in the 2x2 quad are actually inside
- * the triangle's bounds.
- *
- * this is pretty nasty... may need to rework flush_spans again to
- * fix it, if possible.
- */
-static GLuint calculate_mask( struct setup_stage *setup,
- GLint x )
-{
- GLuint mask = 0;
-
- if (x >= setup->span.left[0] && x < setup->span.right[0])
- mask |= MASK_BOTTOM_LEFT;
-
- if (x >= setup->span.left[1] && x < setup->span.right[1])
- mask |= MASK_TOP_LEFT;
-
- if (x+1 >= setup->span.left[0] && x+1 < setup->span.right[0])
- mask |= MASK_BOTTOM_RIGHT;
-
- if (x+1 >= setup->span.left[1] && x+1 < setup->span.right[1])
- mask |= MASK_TOP_RIGHT;
-
- return mask;
-}
-
-
-/**
- * Render a horizontal span of quads
- */
-static void flush_spans( struct setup_stage *setup )
-{
- GLint minleft, maxright;
- GLint x;
-
- switch (setup->span.y_flags) {
- case 3:
- minleft = MIN2(setup->span.left[0], setup->span.left[1]);
- maxright = MAX2(setup->span.right[0], setup->span.right[1]);
- break;
-
- case 1:
- minleft = setup->span.left[0];
- maxright = setup->span.right[0];
- break;
-
- case 2:
- minleft = setup->span.left[1];
- maxright = setup->span.right[1];
- break;
-
- default:
- return;
- }
-
-
- for (x = block(minleft); x <= block(maxright); )
- {
- run_shader_block( setup, x,
- setup->span.y,
- calculate_mask( setup, x ) );
- x += 2;
- }
-
- setup->span.y = 0;
- setup->span.y_flags = 0;
- setup->span.right[0] = 0;
- setup->span.right[1] = 0;
-}
-
-
-static GLboolean setup_sort_vertices( struct setup_stage *setup,
- const struct prim_header *prim )
-{
- const struct vertex_header *v0 = prim->v[0];
- const struct vertex_header *v1 = prim->v[1];
- const struct vertex_header *v2 = prim->v[2];
-
- setup->vprovoke = v2;
-
- /* determine bottom to top order of vertices */
- {
- GLfloat y0 = v0->data[0][1];
- GLfloat y1 = v1->data[0][1];
- GLfloat y2 = v2->data[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->data[0][0] - setup->vmin->data[0][0];
- setup->ebot.dy = setup->vmid->data[0][1] - setup->vmin->data[0][1];
- setup->emaj.dx = setup->vmax->data[0][0] - setup->vmin->data[0][0];
- setup->emaj.dy = setup->vmax->data[0][1] - setup->vmin->data[0][1];
- setup->etop.dx = setup->vmax->data[0][0] - setup->vmid->data[0][0];
- setup->etop.dy = setup->vmax->data[0][1] - setup->vmid->data[0][1];
-
- /* xxx: may need to adjust this sign according to the if-tree
- * above:
- *
- * XXX: this is like 'det', but calculated from screen coords??
- */
- {
- const GLfloat area = (setup->emaj.dx * setup->ebot.dy -
- setup->ebot.dx * setup->emaj.dy);
-
- setup->oneoverarea = 1.0 / area;
- }
-
- /* XXX need to know if this is a front or back-facing triangle:
- * - the GLSL gl_FrontFacing fragment attribute (bool)
- * - two-sided stencil test
- */
- setup->quad.facing = 0;
-
- _mesa_printf("%s one-over-area %f\n", __FUNCTION__, setup->oneoverarea );
-
-
- return GL_TRUE;
-}
-
-
-/**
- * Compute a0 for a constant-valued coefficient (GL_FLAT shading).
- */
-static void const_coeff( struct setup_stage *setup,
- GLuint slot,
- GLuint i )
-{
- setup->coef[slot].dadx[i] = 0;
- setup->coef[slot].dady[i] = 0;
-
- /* need provoking vertex info!
- */
- setup->coef[slot].a0[i] = setup->vprovoke->data[slot][i];
-}
-
-
-/**
- * Compute a0, dadx and dady for a linearly interpolated coefficient,
- * for a triangle.
- */
-static void tri_linear_coeff( struct setup_stage *setup,
- GLuint slot,
- GLuint i)
-{
- GLfloat botda = setup->vmid->data[slot][i] - setup->vmin->data[slot][i];
- GLfloat majda = setup->vmax->data[slot][i] - setup->vmin->data[slot][i];
- GLfloat a = setup->ebot.dy * majda - botda * setup->emaj.dy;
- GLfloat b = setup->emaj.dx * botda - majda * setup->ebot.dx;
-
- setup->coef[slot].dadx[i] = a * setup->oneoverarea;
- setup->coef[slot].dady[i] = b * setup->oneoverarea;
-
- /* 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 (0.5, 0.5).
- *
- * 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.
- */
- setup->coef[slot].a0[i] = (setup->vmin->data[slot][i] -
- (setup->coef[slot].dadx[i] * (setup->vmin->data[0][0] - 0.5) +
- setup->coef[slot].dady[i] * (setup->vmin->data[0][1] - 0.5)));
-
- _mesa_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.
- */
-static void tri_persp_coeff( struct setup_stage *setup,
- GLuint slot,
- GLuint i )
-{
- /* premultiply by 1/w:
- */
- GLfloat mina = setup->vmin->data[slot][i] * setup->vmin->data[0][3];
- GLfloat mida = setup->vmid->data[slot][i] * setup->vmid->data[0][3];
- GLfloat maxa = setup->vmax->data[slot][i] * setup->vmax->data[0][3];
-
- GLfloat botda = mida - mina;
- GLfloat majda = maxa - mina;
- GLfloat a = setup->ebot.dy * majda - botda * setup->emaj.dy;
- GLfloat b = setup->emaj.dx * botda - majda * setup->ebot.dx;
-
- setup->coef[slot].dadx[i] = a * setup->oneoverarea;
- setup->coef[slot].dady[i] = b * setup->oneoverarea;
- setup->coef[slot].a0[i] = (mina -
- (setup->coef[slot].dadx[i] * (setup->vmin->data[0][0] - 0.5) +
- setup->coef[slot].dady[i] * (setup->vmin->data[0][1] - 0.5)));
-}
-
-
-
-/**
- * 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_stage *setup )
-{
- const enum interp_mode *interp = setup->stage.generic->interp;
- GLuint slot, j;
-
- /* z and w are done by linear interpolation:
- */
- tri_linear_coeff(setup, 0, 2);
- tri_linear_coeff(setup, 0, 3);
-
- /* setup interpolation for all the remaining attributes:
- */
- for (slot = 1; slot < setup->quad.nr_attrs; slot++) {
- switch (interp[slot]) {
- case INTERP_CONSTANT:
- for (j = 0; j < NUM_CHANNELS; j++)
- const_coeff(setup, slot, j);
- break;
-
- case INTERP_LINEAR:
- for (j = 0; j < NUM_CHANNELS; j++)
- tri_linear_coeff(setup, slot, j);
- break;
-
- case INTERP_PERSPECTIVE:
- for (j = 0; j < NUM_CHANNELS; j++)
- tri_persp_coeff(setup, slot, j);
- break;
- }
- }
-}
-
-
-
-static void setup_tri_edges( struct setup_stage *setup )
-{
- GLfloat vmin_x = setup->vmin->data[0][0] + 0.5;
- GLfloat vmid_x = setup->vmid->data[0][0] + 0.5;
-
- GLfloat vmin_y = setup->vmin->data[0][1] - 0.5;
- GLfloat vmid_y = setup->vmid->data[0][1] - 0.5;
- GLfloat vmax_y = setup->vmax->data[0][1] - 0.5;
-
- setup->emaj.sy = ceilf(vmin_y);
- setup->emaj.lines = (GLint) ceilf(vmax_y - setup->emaj.sy);
- setup->emaj.dxdy = setup->emaj.dx / setup->emaj.dy;
- setup->emaj.sx = vmin_x + (setup->emaj.sy - vmin_y) * setup->emaj.dxdy;
-
- setup->etop.sy = ceilf(vmid_y);
- setup->etop.lines = (GLint) ceilf(vmax_y - setup->etop.sy);
- setup->etop.dxdy = setup->etop.dx / setup->etop.dy;
- setup->etop.sx = vmid_x + (setup->etop.sy - vmid_y) * setup->etop.dxdy;
-
- setup->ebot.sy = ceilf(vmin_y);
- setup->ebot.lines = (GLint) ceilf(vmid_y - setup->ebot.sy);
- setup->ebot.dxdy = setup->ebot.dx / setup->ebot.dy;
- setup->ebot.sx = vmin_x + (setup->ebot.sy - vmin_y) * setup->ebot.dxdy;
-}
-
-
-/**
- * Render the upper or lower half of a triangle.
- * Scissoring is applied here too.
- */
-static void subtriangle( struct setup_stage *setup,
- struct edge *eleft,
- struct edge *eright,
- GLuint lines )
-{
- GLint y, start_y, finish_y;
- GLint sy = (GLint)eleft->sy;
-
- assert((GLint)eleft->sy == (GLint) eright->sy);
- assert((GLint)eleft->sy >= 0); /* catch bug in x64? */
-
- /* scissor y:
- */
- if (setup->stage.generic->setup.scissor) {
- start_y = sy;
- finish_y = start_y + lines;
-
- if (start_y < setup->stage.generic->scissor.miny)
- start_y = setup->stage.generic->scissor.miny;
-
- if (finish_y > setup->stage.generic->scissor.maxy)
- finish_y = setup->stage.generic->scissor.maxy;
-
- start_y -= sy;
- finish_y -= sy;
- }
- else {
- start_y = 0;
- finish_y = lines;
- }
-
- _mesa_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.
- */
- GLint left = (GLint)(eleft->sx + y * eleft->dxdy);
- GLint right = (GLint)(eright->sx + y * eright->dxdy);
-
- /* scissor x:
- */
- if (setup->stage.generic->setup.scissor) {
- if (left < setup->stage.generic->scissor.minx)
- left = setup->stage.generic->scissor.minx;
-
- if (right > setup->stage.generic->scissor.maxx)
- right = setup->stage.generic->scissor.maxx;
- }
-
- if (left < right) {
- GLint _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;
- setup->span.y_flags |= 1<<(_y&1);
- }
- }
-
-
- /* 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;
-}
-
-
-/**
- * Do setup for triangle rasterization, then render the triangle.
- */
-static void setup_tri( struct prim_stage *stage,
- struct prim_header *prim )
-{
- struct setup_stage *setup = setup_stage( stage );
-
- _mesa_printf("%s\n", __FUNCTION__ );
-
- setup_sort_vertices( setup, prim );
- setup_tri_coefficients( setup );
- setup_tri_edges( setup );
-
- setup->span.y = 0;
- setup->span.y_flags = 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 );
-}
-
-
-
-/**
- * Compute a0, dadx and dady for a linearly interpolated coefficient,
- * for a line.
- */
-static void
-line_linear_coeff(struct setup_stage *setup, GLuint slot, GLuint i)
-{
- const GLfloat dz = setup->vmax->data[slot][i] - setup->vmin->data[slot][i];
- const GLfloat dadx = dz * setup->emaj.dx * setup->oneoverarea;
- const GLfloat dady = dz * setup->emaj.dy * setup->oneoverarea;
- setup->coef[slot].dadx[i] = dadx;
- setup->coef[slot].dady[i] = dady;
- setup->coef[slot].a0[i]
- = (setup->vmin->data[slot][i] -
- (dadx * (setup->vmin->data[0][0] - 0.5) +
- dady * (setup->vmin->data[0][1] - 0.5)));
-}
-
-
-/**
- * Compute a0, dadx and dady for a perspective-corrected interpolant,
- * for a line.
- */
-static void
-line_persp_coeff(struct setup_stage *setup, GLuint slot, GLuint i)
-{
- /* XXX to do */
- line_linear_coeff(setup, slot, i); /* XXX temporary */
-}
-
-
-/**
- * Compute the setup->coef[] array dadx, dady, a0 values.
- * Must be called after setup->vmin,vmax are initialized.
- */
-static INLINE void
-setup_line_coefficients(struct setup_stage *setup, struct prim_header *prim)
-{
- const enum interp_mode *interp = setup->stage.generic->interp;
- GLuint slot, j;
-
- /* use setup->vmin, vmax to point to vertices */
- setup->vprovoke = prim->v[1];
- setup->vmin = prim->v[0];
- setup->vmax = prim->v[1];
-
- setup->emaj.dx = setup->vmax->data[0][0] - setup->vmin->data[0][0];
- setup->emaj.dy = setup->vmax->data[0][1] - setup->vmin->data[0][1];
- /* NOTE: this is not really 1/area */
- setup->oneoverarea = 1.0 / (setup->emaj.dx * setup->emaj.dx +
- setup->emaj.dy * setup->emaj.dy);
-
- /* z and w are done by linear interpolation:
- */
- line_linear_coeff(setup, 0, 2);
- line_linear_coeff(setup, 0, 3);
-
- /* setup interpolation for all the remaining attributes:
- */
- for (slot = 1; slot < setup->quad.nr_attrs; slot++) {
- switch (interp[slot]) {
- case INTERP_CONSTANT:
- for (j = 0; j < NUM_CHANNELS; j++)
- const_coeff(setup, slot, j);
- break;
-
- case INTERP_LINEAR:
- for (j = 0; j < NUM_CHANNELS; j++)
- line_linear_coeff(setup, slot, j);
- break;
-
- case INTERP_PERSPECTIVE:
- for (j = 0; j < NUM_CHANNELS; j++)
- line_persp_coeff(setup, slot, j);
- break;
- }
- }
-}
-
-
-/**
- * Plot a pixel in a line segment.
- */
-static INLINE void
-plot(struct setup_stage *setup, GLint x, GLint y)
-{
- const GLint iy = y & 1;
- const GLint ix = x & 1;
- const GLint quadX = x - ix;
- const GLint quadY = y - iy;
- const GLint mask = (1 << ix) << (2 * iy);
-
- if (quadX != setup->quad.x0 ||
- quadY != setup->quad.y0)
- {
- /* flush prev quad, start new quad */
-
- if (setup->quad.x0 != -1)
- quad_shade(setup->stage.generic, &setup->quad);
-
- setup->quad.x0 = quadX;
- setup->quad.y0 = quadY;
- setup->quad.mask = 0x0;
- }
-
- setup->quad.mask |= mask;
-}
-
-
-
-/**
- * Do setup for line rasterization, then render the line.
- * XXX single-pixel width, no stipple, etc
- * XXX no scissoring yet.
- */
-static void
-setup_line(struct prim_stage *stage, struct prim_header *prim)
-{
- const struct vertex_header *v0 = prim->v[0];
- const struct vertex_header *v1 = prim->v[1];
- struct setup_stage *setup = setup_stage( stage );
-
- GLint x0 = (GLint) v0->data[0][0];
- GLint x1 = (GLint) v1->data[0][0];
- GLint y0 = (GLint) v0->data[0][1];
- GLint y1 = (GLint) v1->data[0][1];
- GLint dx = x1 - x0;
- GLint dy = y1 - y0;
- GLint xstep, ystep;
-
- if (dx == 0 && dy == 0)
- return;
-
- setup_line_coefficients(setup, prim);
-
- 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);
-
- setup->quad.x0 = setup->quad.y0 = -1;
- setup->quad.mask = 0x0;
-
- if (dx > dy) {
- /*** X-major line ***/
- GLint i;
- const GLint errorInc = dy + dy;
- GLint error = errorInc - dx;
- const GLint 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 ***/
- GLint i;
- const GLint errorInc = dx + dx;
- GLint error = errorInc - dy;
- const GLint 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.mask) {
- quad_shade(setup->stage.generic, &setup->quad);
- }
-}
-
-
-/**
- * Do setup for point rasterization, then render the point.
- * Round or square points...
- * XXX could optimize a lot for 1-pixel points.
- */
-static void
-setup_point(struct prim_stage *stage, struct prim_header *prim)
-{
- struct setup_stage *setup = setup_stage( stage );
- GLfloat halfSize = 7.3; /*XXX this is a vertex attrib */
- GLfloat halfSizeSquared = halfSize * halfSize;
- const struct vertex_header *v0 = prim->v[0];
- const GLfloat x = v0->data[FRAG_ATTRIB_WPOS][0];
- const GLfloat y = v0->data[FRAG_ATTRIB_WPOS][1];
- const GLint ixmin = block((GLint) (x - halfSize));
- const GLint ixmax = block((GLint) (x + halfSize));
- const GLint iymin = block((GLint) (y - halfSize));
- const GLint iymax = block((GLint) (y + halfSize));
- GLboolean round = GL_TRUE;
- GLint ix, iy;
- GLuint slot, j;
-
- /* 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 = prim->v[0];
- const_coeff(setup, 0, 2);
- const_coeff(setup, 0, 3);
- for (slot = 1; slot < setup->quad.nr_attrs; slot++) {
- for (j = 0; j < NUM_CHANNELS; j++)
- const_coeff(setup, slot, j);
- }
-
- /* XXX need to clip against scissor bounds too */
-
- for (iy = iymin; iy <= iymax; iy += 2) {
- for (ix = ixmin; ix <= ixmax; ix += 2) {
-
- if (round) {
- /* rounded points */
- /* XXX for GL_SMOOTH, need to compute per-fragment coverage too */
- GLfloat dx, dy;
-
- setup->quad.mask = 0x0;
-
- dx = (ix + 0.5) - x;
- dy = (iy + 0.5) - y;
- if (dx * dx + dy * dy <= halfSizeSquared)
- setup->quad.mask |= MASK_BOTTOM_LEFT;
-
- dx = (ix + 1.5) - x;
- dy = (iy + 0.5) - y;
- if (dx * dx + dy * dy <= halfSizeSquared)
- setup->quad.mask |= MASK_BOTTOM_RIGHT;
-
- dx = (ix + 0.5) - x;
- dy = (iy + 1.5) - y;
- if (dx * dx + dy * dy <= halfSizeSquared)
- setup->quad.mask |= MASK_TOP_LEFT;
-
- dx = (ix + 1.5) - x;
- dy = (iy + 1.5) - y;
- if (dx * dx + dy * dy <= halfSizeSquared)
- setup->quad.mask |= MASK_TOP_RIGHT;
- }
- else {
- /* square points */
- setup->quad.mask = 0xf;
-
- if (ix + 0.5 < x - halfSize)
- setup->quad.mask &= (MASK_BOTTOM_RIGHT | MASK_TOP_RIGHT);
-
- if (ix + 1.5 > x + halfSize)
- setup->quad.mask &= (MASK_BOTTOM_LEFT | MASK_TOP_LEFT);
-
- if (iy + 0.5 < y - halfSize)
- setup->quad.mask &= (MASK_TOP_LEFT | MASK_TOP_RIGHT);
-
- if (iy + 1.5 > y + halfSize)
- setup->quad.mask &= (MASK_BOTTOM_LEFT | MASK_BOTTOM_RIGHT);
- }
-
- if (setup->quad.mask) {
- setup->quad.x0 = ix;
- setup->quad.y0 = iy;
- quad_shade( setup->stage.generic, &setup->quad );
- }
- }
- }
-}
-
-
-
-static void setup_end( struct prim_stage *stage )
-{
-}
-
-
-struct prim_stage *prim_setup( struct generic_context *generic )
-{
- struct setup_stage *setup = CALLOC_STRUCT(setup_stage);
-
- setup->stage.generic = generic;
- setup->stage.begin = setup_begin;
- setup->stage.point = setup_point;
- setup->stage.line = setup_line;
- setup->stage.tri = setup_tri;
- setup->stage.end = setup_end;
-
- setup->quad.coef = setup->coef;
-
- return &setup->stage;
-}
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-20 06:25:38 +0000