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diff --git a/src/mesa/pipe/cell/spu/spu_tri.c b/src/mesa/pipe/cell/spu/spu_tri.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.
+ *
+ **************************************************************************/
+
+/**
+ * Triangle rendering within a tile.
+ */
+
+#include "pipe/p_compiler.h"
+#include "pipe/p_format.h"
+#include "pipe/p_util.h"
+#include "spu_main.h"
+#include "spu_tile.h"
+#include "spu_tri.h"
+
+
+
+/**
+ * Simplified types taken from other parts of Gallium
+ */
+
+struct vertex_header {
+ float data[2][4]; /* pos and color */
+};
+
+struct prim_header {
+ struct vertex_header *v[3];
+};
+
+
+
+
+#if 1
+
+/* XXX fix this */
+#undef CEILF
+#define CEILF(X) ((float) (int) ((X) + 0.99999))
+
+
+#define QUAD_TOP_LEFT 0
+#define QUAD_TOP_RIGHT 1
+#define QUAD_BOTTOM_LEFT 2
+#define QUAD_BOTTOM_RIGHT 3
+#define MASK_TOP_LEFT (1 << QUAD_TOP_LEFT)
+#define MASK_TOP_RIGHT (1 << QUAD_TOP_RIGHT)
+#define MASK_BOTTOM_LEFT (1 << QUAD_BOTTOM_LEFT)
+#define MASK_BOTTOM_RIGHT (1 << QUAD_BOTTOM_RIGHT)
+#define MASK_ALL 0xf
+
+#define PIPE_MAX_SHADER_INPUTS 8 /* XXX temp */
+
+#endif
+
+
+#define DEBUG_VERTS 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 */
+};
+
+
+struct interp_coef
+{
+ float a0[4];
+ float dadx[4];
+ float dady[4];
+};
+
+/**
+ * Triangle setup info (derived from draw_stage).
+ * Also used for line drawing (taking some liberties).
+ */
+struct setup_stage {
+
+ /* 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;
+
+ float oneoverarea;
+
+ uint tx, ty;
+
+ int cliprect_minx, cliprect_maxx, cliprect_miny, cliprect_maxy;
+
+#if 0
+ struct tgsi_interp_coef coef[PIPE_MAX_SHADER_INPUTS];
+#else
+ struct interp_coef coef[PIPE_MAX_SHADER_INPUTS];
+#endif
+
+#if 0
+ struct quad_header quad;
+#endif
+
+ struct {
+ int left[2]; /**< [0] = row0, [1] = row1 */
+ int right[2];
+ int y;
+ unsigned y_flags;
+ unsigned mask; /**< mask of MASK_BOTTOM/TOP_LEFT/RIGHT bits */
+ } span;
+};
+
+
+#if 0
+/**
+ * Basically a cast wrapper.
+ */
+static INLINE struct setup_stage *setup_stage( struct draw_stage *stage )
+{
+ return (struct setup_stage *)stage;
+}
+#endif
+
+#if 0
+/**
+ * Clip setup->quad against the scissor/surface bounds.
+ */
+static INLINE void
+quad_clip(struct setup_stage *setup)
+{
+ 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 (setup->quad.x0 >= maxx ||
+ setup->quad.y0 >= maxy ||
+ setup->quad.x0 + 1 < minx ||
+ setup->quad.y0 + 1 < miny) {
+ /* totally clipped */
+ setup->quad.mask = 0x0;
+ return;
+ }
+ if (setup->quad.x0 < minx)
+ setup->quad.mask &= (MASK_BOTTOM_RIGHT | MASK_TOP_RIGHT);
+ if (setup->quad.y0 < miny)
+ setup->quad.mask &= (MASK_BOTTOM_LEFT | MASK_BOTTOM_RIGHT);
+ if (setup->quad.x0 == maxx - 1)
+ setup->quad.mask &= (MASK_BOTTOM_LEFT | MASK_TOP_LEFT);
+ if (setup->quad.y0 == maxy - 1)
+ setup->quad.mask &= (MASK_TOP_LEFT | MASK_TOP_RIGHT);
+}
+#endif
+
+#if 0
+/**
+ * Emit a quad (pass to next stage) with clipping.
+ */
+static INLINE void
+clip_emit_quad(struct setup_stage *setup)
+{
+ quad_clip(setup);
+ if (setup->quad.mask) {
+ struct softpipe_context *sp = setup->softpipe;
+ sp->quad.first->run(sp->quad.first, &setup->quad);
+ }
+}
+#endif
+
+/**
+ * Evaluate attribute coefficients (plane equations) to compute
+ * attribute values for the four fragments in a quad.
+ * Eg: four colors will be compute.
+ */
+static INLINE void
+eval_coeff( struct setup_stage *setup, uint slot,
+ float x, float y, float result[4][4])
+{
+ uint i;
+ const float *dadx = setup->coef[slot].dadx;
+ const float *dady = setup->coef[slot].dady;
+
+ /* loop over XYZW comps */
+ for (i = 0; i < 4; i++) {
+ result[QUAD_TOP_LEFT][i] = setup->coef[slot].a0[i] + x * dadx[i] + y * dady[i];
+ result[QUAD_TOP_RIGHT][i] = result[0][i] + dadx[i];
+ result[QUAD_BOTTOM_LEFT][i] = result[0][i] + dady[i];
+ result[QUAD_BOTTOM_RIGHT][i] = result[0][i] + dadx[i] + dady[i];
+ }
+}
+
+
+static INLINE void
+eval_z( struct setup_stage *setup,
+ float x, float y, float result[4])
+{
+ uint slot = 0;
+ uint i = 2;
+ const float *dadx = setup->coef[slot].dadx;
+ const float *dady = setup->coef[slot].dady;
+
+ result[QUAD_TOP_LEFT] = setup->coef[slot].a0[i] + x * dadx[i] + y * dady[i];
+ result[QUAD_TOP_RIGHT] = result[0] + dadx[i];
+ result[QUAD_BOTTOM_LEFT] = result[0] + dady[i];
+ result[QUAD_BOTTOM_RIGHT] = result[0] + dadx[i] + dady[i];
+}
+
+
+static INLINE uint
+pack_color(const float color[4])
+{
+ uint r = (uint) (color[0] * 255.0);
+ uint g = (uint) (color[1] * 255.0);
+ uint b = (uint) (color[2] * 255.0);
+ uint a = (uint) (color[3] * 255.0);
+ switch (fb.color_format) {
+ case PIPE_FORMAT_A8R8G8B8_UNORM:
+ return (a << 24) | (r << 16) | (g << 8) | b;
+ case PIPE_FORMAT_B8G8R8A8_UNORM:
+ return (b << 24) | (g << 16) | (r << 8) | a;
+ default:
+ ASSERT(0);
+ return 0;
+ }
+}
+
+
+/**
+ * Emit a quad (pass to next stage). No clipping is done.
+ */
+static INLINE void
+emit_quad( struct setup_stage *setup, int x, int y, unsigned mask )
+{
+#if 0
+ struct softpipe_context *sp = setup->softpipe;
+ setup->quad.x0 = x;
+ setup->quad.y0 = y;
+ setup->quad.mask = mask;
+ sp->quad.first->run(sp->quad.first, &setup->quad);
+#else
+ /* Cell: "write" quad fragments to the tile by setting prim color */
+ int ix = x - setup->cliprect_minx;
+ int iy = y - setup->cliprect_miny;
+ float colors[4][4];
+ uint z;
+
+ eval_coeff(setup, 1, (float) x, (float) y, colors);
+
+ if (fb.depth_format == PIPE_FORMAT_Z16_UNORM) {
+ float zvals[4];
+ eval_z(setup, (float) x, (float) y, zvals);
+
+ if (tile_status_z[setup->ty][setup->tx] == TILE_STATUS_CLEAR) {
+ /* now, _really_ clear the tile */
+ clear_tile_z(ztile, fb.depth_clear_value);
+ }
+ else {
+ /* make sure we've got the tile from main mem */
+ wait_on_mask(1 << TAG_READ_TILE_Z);
+ }
+ tile_status_z[setup->ty][setup->tx] = TILE_STATUS_DIRTY;
+
+ if (mask & MASK_TOP_LEFT) {
+ z = (uint) (zvals[0] * 65535.0);
+ if (z < ztile[iy][ix])
+ ztile[iy][ix] = z;
+ else
+ mask &= ~MASK_TOP_LEFT;
+ }
+
+ if (mask & MASK_TOP_RIGHT) {
+ z = (uint) (zvals[1] * 65535.0);
+ if (z < ztile[iy][ix+1])
+ ztile[iy][ix+1] = z;
+ else
+ mask &= ~MASK_TOP_RIGHT;
+ }
+
+ if (mask & MASK_BOTTOM_LEFT) {
+ z = (uint) (zvals[2] * 65535.0);
+ if (z < ztile[iy+1][ix])
+ ztile[iy+1][ix] = z;
+ else
+ mask &= ~MASK_BOTTOM_LEFT;
+ }
+
+ if (mask & MASK_BOTTOM_RIGHT) {
+ z = (uint) (zvals[3] * 65535.0);
+ if (z < ztile[iy+1][ix+1])
+ ztile[iy+1][ix+1] = z;
+ else
+ mask &= ~MASK_BOTTOM_RIGHT;
+ }
+ }
+
+ if (mask) {
+ if (tile_status[setup->ty][setup->tx] == TILE_STATUS_CLEAR) {
+ /* now, _really_ clear the tile */
+ clear_tile(ctile, fb.color_clear_value);
+ }
+ else {
+ /* make sure we've got the tile from main mem */
+ wait_on_mask(1 << TAG_READ_TILE_COLOR);
+ }
+ tile_status[setup->ty][setup->tx] = TILE_STATUS_DIRTY;
+
+ if (mask & MASK_TOP_LEFT)
+ ctile[iy][ix] = pack_color(colors[QUAD_TOP_LEFT]);
+ if (mask & MASK_TOP_RIGHT)
+ ctile[iy][ix+1] = pack_color(colors[QUAD_TOP_RIGHT]);
+ if (mask & MASK_BOTTOM_LEFT)
+ ctile[iy+1][ix] = pack_color(colors[QUAD_BOTTOM_LEFT]);
+ if (mask & MASK_BOTTOM_RIGHT)
+ ctile[iy+1][ix+1] = pack_color(colors[QUAD_BOTTOM_RIGHT]);
+ }
+#endif
+}
+
+
+/**
+ * Given an X or Y coordinate, return the block/quad coordinate that it
+ * belongs to.
+ */
+static INLINE int block( int x )
+{
+ return x & ~1;
+}
+
+
+/**
+ * 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 unsigned calculate_mask( struct setup_stage *setup, int x )
+{
+ unsigned mask = 0x0;
+
+ if (x >= setup->span.left[0] && x < setup->span.right[0])
+ mask |= MASK_TOP_LEFT;
+
+ if (x >= setup->span.left[1] && x < setup->span.right[1])
+ mask |= MASK_BOTTOM_LEFT;
+
+ if (x+1 >= setup->span.left[0] && x+1 < setup->span.right[0])
+ mask |= MASK_TOP_RIGHT;
+
+ if (x+1 >= setup->span.left[1] && x+1 < setup->span.right[1])
+ mask |= MASK_BOTTOM_RIGHT;
+
+ return mask;
+}
+
+
+/**
+ * Render a horizontal span of quads
+ */
+static void flush_spans( struct setup_stage *setup )
+{
+ int minleft, maxright;
+ int x;
+
+ switch (setup->span.y_flags) {
+ case 0x3:
+ /* both odd and even lines written (both quad rows) */
+ minleft = MIN2(setup->span.left[0], setup->span.left[1]);
+ maxright = MAX2(setup->span.right[0], setup->span.right[1]);
+ break;
+
+ case 0x1:
+ /* only even line written (quad top row) */
+ minleft = setup->span.left[0];
+ maxright = setup->span.right[0];
+ break;
+
+ case 0x2:
+ /* only odd line written (quad bottom row) */
+ minleft = setup->span.left[1];
+ maxright = setup->span.right[1];
+ break;
+
+ default:
+ return;
+ }
+
+ /* XXX this loop could be moved into the above switch cases and
+ * calculate_mask() could be simplified a bit...
+ */
+ for (x = block(minleft); x <= block(maxright); x += 2) {
+ emit_quad( setup, x, setup->span.y,
+ calculate_mask( setup, x ) );
+ }
+
+ setup->span.y = 0;
+ setup->span.y_flags = 0;
+ setup->span.right[0] = 0;
+ setup->span.right[1] = 0;
+}
+
+#if DEBUG_VERTS
+static void print_vertex(const struct setup_stage *setup,
+ const struct vertex_header *v)
+{
+ int i;
+ fprintf(stderr, "Vertex: (%p)\n", v);
+ for (i = 0; i < setup->quad.nr_attrs; i++) {
+ fprintf(stderr, " %d: %f %f %f %f\n", i,
+ v->data[i][0], v->data[i][1], v->data[i][2], v->data[i][3]);
+ }
+}
+#endif
+
+static boolean 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];
+
+#if DEBUG_VERTS
+ fprintf(stderr, "Triangle:\n");
+ print_vertex(setup, v0);
+ print_vertex(setup, v1);
+ print_vertex(setup, v2);
+#endif
+
+ setup->vprovoke = v2;
+
+ /* determine bottom to top order of vertices */
+ {
+ float y0 = v0->data[0][1];
+ float y1 = v1->data[0][1];
+ float 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;
+ }
+ }
+ }
+
+ /* Check if triangle is completely outside the tile bounds */
+ if (setup->vmin->data[0][1] > setup->cliprect_maxy)
+ return FALSE;
+ if (setup->vmax->data[0][1] < setup->cliprect_miny)
+ return FALSE;
+ if (setup->vmin->data[0][0] < setup->cliprect_minx &&
+ setup->vmid->data[0][0] < setup->cliprect_minx &&
+ setup->vmax->data[0][0] < setup->cliprect_minx)
+ return FALSE;
+ if (setup->vmin->data[0][0] > setup->cliprect_maxx &&
+ setup->vmid->data[0][0] > setup->cliprect_maxx &&
+ setup->vmax->data[0][0] > setup->cliprect_maxx)
+ return FALSE;
+
+ 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];
+
+ /*
+ * 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;
+ /*
+ _mesa_printf("%s one-over-area %f area %f det %f\n",
+ __FUNCTION__, setup->oneoverarea, area, prim->det );
+ */
+ }
+
+#if 0
+ /* 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
+ */
+ setup->quad.facing = (prim->det > 0.0) ^ (setup->softpipe->rasterizer->front_winding == PIPE_WINDING_CW);
+#endif
+
+ return TRUE;
+}
+
+
+#if 0
+/**
+ * Compute a0 for a constant-valued coefficient (GL_FLAT shading).
+ * The value value comes from vertex->data[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_stage *setup,
+ unsigned slot,
+ unsigned i )
+{
+ assert(slot < PIPE_MAX_SHADER_INPUTS);
+ assert(i <= 3);
+
+ 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];
+}
+#endif
+
+
+/**
+ * Compute a0, dadx and dady for a linearly interpolated coefficient,
+ * for a triangle.
+ */
+static void tri_linear_coeff( struct setup_stage *setup,
+ uint slot, uint firstComp, uint lastComp )
+{
+ uint i;
+ for (i = firstComp; i < lastComp; i++) {
+ float botda = setup->vmid->data[slot][i] - setup->vmin->data[slot][i];
+ float majda = setup->vmax->data[slot][i] - setup->vmin->data[slot][i];
+ float a = setup->ebot.dy * majda - botda * setup->emaj.dy;
+ float b = setup->emaj.dx * botda - majda * setup->ebot.dx;
+
+ ASSERT(slot < PIPE_MAX_SHADER_INPUTS);
+
+ 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] - 0.5f) +
+ setup->coef[slot].dady[i] * (setup->vmin->data[0][1] - 0.5f)));
+ }
+
+ /*
+ _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]);
+ */
+}
+
+
+#if 0
+/**
+ * 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 tri_persp_coeff( struct setup_stage *setup,
+ unsigned slot,
+ unsigned i )
+{
+ /* premultiply by 1/w:
+ */
+ float mina = setup->vmin->data[slot][i] * setup->vmin->data[0][3];
+ float mida = setup->vmid->data[slot][i] * setup->vmid->data[0][3];
+ float maxa = setup->vmax->data[slot][i] * setup->vmax->data[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;
+
+ /*
+ printf("tri persp %d,%d: %f %f %f\n", slot, i,
+ setup->vmin->data[slot][i],
+ setup->vmid->data[slot][i],
+ setup->vmax->data[slot][i]
+ );
+ */
+
+ assert(slot < PIPE_MAX_SHADER_INPUTS);
+ assert(i <= 3);
+
+ 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] - 0.5f) +
+ setup->coef[slot].dady[i] * (setup->vmin->data[0][1] - 0.5f)));
+}
+#endif
+
+
+/**
+ * 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 )
+{
+#if 0
+ const enum interp_mode *interp = setup->softpipe->vertex_info.interp_mode;
+ unsigned 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;
+
+ default:
+ /* invalid interp mode */
+ assert(0);
+ }
+ }
+#else
+ tri_linear_coeff(setup, 0, 2, 3); /* slot 0, z */
+ tri_linear_coeff(setup, 1, 0, 4); /* slot 1, color */
+#endif
+}
+
+
+static void setup_tri_edges( struct setup_stage *setup )
+{
+ float vmin_x = setup->vmin->data[0][0] + 0.5f;
+ float vmid_x = setup->vmid->data[0][0] + 0.5f;
+
+ float vmin_y = setup->vmin->data[0][1] - 0.5f;
+ float vmid_y = setup->vmid->data[0][1] - 0.5f;
+ float vmax_y = setup->vmax->data[0][1] - 0.5f;
+
+ setup->emaj.sy = CEILF(vmin_y);
+ setup->emaj.lines = (int) 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 = (int) 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 = (int) 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/cliprect is applied here too.
+ */
+static void subtriangle( struct setup_stage *setup,
+ struct edge *eleft,
+ struct edge *eright,
+ unsigned lines )
+{
+ const int minx = setup->cliprect_minx;
+ const int maxx = setup->cliprect_maxx;
+ const int miny = setup->cliprect_miny;
+ const int maxy = setup->cliprect_maxy;
+ int y, start_y, finish_y;
+ int sy = (int)eleft->sy;
+
+ ASSERT((int)eleft->sy == (int) eright->sy);
+
+ /* clip top/bottom */
+ start_y = sy;
+ finish_y = sy + lines;
+
+ if (start_y < miny)
+ start_y = miny;
+
+ if (finish_y > maxy)
+ finish_y = maxy;
+
+ start_y -= sy;
+ finish_y -= sy;
+
+ /*
+ _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.
+ */
+ 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;
+ 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 setup_stage *setup, struct prim_header *prim)
+{
+ if (!setup_sort_vertices( setup, prim )) {
+ return; /* totally clipped */
+ }
+
+ setup_tri_coefficients( setup );
+ setup_tri_edges( setup );
+
+#if 0
+ setup->quad.prim = PRIM_TRI;
+#endif
+
+ 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 );
+}
+
+
+
+/**
+ * Draw triangle into tile at (tx, ty) (tile coords)
+ * The tile data should have already been fetched.
+ */
+void
+tri_draw(const float *v0, const float *v1, const float *v2, uint tx, uint ty)
+{
+ struct prim_header tri;
+ struct setup_stage setup;
+
+ tri.v[0] = (struct vertex_header *) v0;
+ tri.v[1] = (struct vertex_header *) v1;
+ tri.v[2] = (struct vertex_header *) v2;
+
+ setup.tx = tx;
+ setup.ty = ty;
+
+ /* set clipping bounds to tile bounds */
+ setup.cliprect_minx = tx * TILE_SIZE;
+ setup.cliprect_miny = ty * TILE_SIZE;
+ setup.cliprect_maxx = (tx + 1) * TILE_SIZE;
+ setup.cliprect_maxy = (ty + 1) * TILE_SIZE;
+
+ setup_tri(&setup, &tri);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-08-08 12:14:02 +0000