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diff --git a/src/gallium/drivers/cell/spu/spu_tri.c b/src/gallium/drivers/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 <transpose_matrix4x4.h>
+#include "pipe/p_compiler.h"
+#include "pipe/p_format.h"
+#include "util/u_math.h"
+#include "spu_colorpack.h"
+#include "spu_main.h"
+#include "spu_texture.h"
+#include "spu_tile.h"
+#include "spu_tri.h"
+
+
+/** Masks are uint[4] vectors with each element being 0 or 0xffffffff */
+typedef vector unsigned int mask_t;
+
+
+
+/**
+ * Simplified types taken from other parts of Gallium
+ */
+struct vertex_header {
+ vector float data[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 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
+{
+ vector float a0;
+ vector float dadx;
+ vector float dady;
+};
+
+
+/**
+ * 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; /* XXX maybe make into vector? */
+
+ uint facing;
+
+ uint tx, ty; /**< position of current tile (x, y) */
+
+ int cliprect_minx, cliprect_maxx, cliprect_miny, cliprect_maxy;
+
+ struct interp_coef coef[PIPE_MAX_SHADER_INPUTS];
+
+ 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;
+};
+
+
+static struct setup_stage setup;
+
+
+/**
+ * Evaluate attribute coefficients (plane equations) to compute
+ * attribute values for the four fragments in a quad.
+ * Eg: four colors will be computed (in AoS format).
+ */
+static INLINE void
+eval_coeff(uint slot, float x, float y, vector float w, vector float result[4])
+{
+ switch (spu.vertex_info.attrib[slot].interp_mode) {
+ case INTERP_CONSTANT:
+ result[QUAD_TOP_LEFT] =
+ result[QUAD_TOP_RIGHT] =
+ result[QUAD_BOTTOM_LEFT] =
+ result[QUAD_BOTTOM_RIGHT] = setup.coef[slot].a0;
+ break;
+ case INTERP_LINEAR:
+ {
+ vector float dadx = setup.coef[slot].dadx;
+ vector float dady = setup.coef[slot].dady;
+ vector float topLeft =
+ spu_add(setup.coef[slot].a0,
+ spu_add(spu_mul(spu_splats(x), dadx),
+ spu_mul(spu_splats(y), dady)));
+
+ result[QUAD_TOP_LEFT] = topLeft;
+ result[QUAD_TOP_RIGHT] = spu_add(topLeft, dadx);
+ result[QUAD_BOTTOM_LEFT] = spu_add(topLeft, dady);
+ result[QUAD_BOTTOM_RIGHT] = spu_add(spu_add(topLeft, dadx), dady);
+ }
+ break;
+ case INTERP_PERSPECTIVE:
+ {
+ vector float dadx = setup.coef[slot].dadx;
+ vector float dady = setup.coef[slot].dady;
+ vector float topLeft =
+ spu_add(setup.coef[slot].a0,
+ spu_add(spu_mul(spu_splats(x), dadx),
+ spu_mul(spu_splats(y), dady)));
+
+ vector float wInv = spu_re(w); /* 1.0 / w */
+
+ result[QUAD_TOP_LEFT] = spu_mul(topLeft, wInv);
+ result[QUAD_TOP_RIGHT] = spu_mul(spu_add(topLeft, dadx), wInv);
+ result[QUAD_BOTTOM_LEFT] = spu_mul(spu_add(topLeft, dady), wInv);
+ result[QUAD_BOTTOM_RIGHT] = spu_mul(spu_add(spu_add(topLeft, dadx), dady), wInv);
+ }
+ break;
+ case INTERP_POS:
+ case INTERP_NONE:
+ break;
+ default:
+ ASSERT(0);
+ }
+}
+
+
+/**
+ * As above, but return 4 vectors in SOA format.
+ * XXX this will all be re-written someday.
+ */
+static INLINE void
+eval_coeff_soa(uint slot, float x, float y, vector float w, vector float result[4])
+{
+ eval_coeff(slot, x, y, w, result);
+ _transpose_matrix4x4(result, result);
+}
+
+
+/** Evalute coefficients to get Z for four pixels in a quad */
+static INLINE vector float
+eval_z(float x, float y)
+{
+ const uint slot = 0;
+ const float dzdx = spu_extract(setup.coef[slot].dadx, 2);
+ const float dzdy = spu_extract(setup.coef[slot].dady, 2);
+ const float topLeft = spu_extract(setup.coef[slot].a0, 2) + x * dzdx + y * dzdy;
+ const vector float topLeftv = spu_splats(topLeft);
+ const vector float derivs = (vector float) { 0.0, dzdx, dzdy, dzdx + dzdy };
+ return spu_add(topLeftv, derivs);
+}
+
+
+/** Evalute coefficients to get W for four pixels in a quad */
+static INLINE vector float
+eval_w(float x, float y)
+{
+ const uint slot = 0;
+ const float dwdx = spu_extract(setup.coef[slot].dadx, 3);
+ const float dwdy = spu_extract(setup.coef[slot].dady, 3);
+ const float topLeft = spu_extract(setup.coef[slot].a0, 3) + x * dwdx + y * dwdy;
+ const vector float topLeftv = spu_splats(topLeft);
+ const vector float derivs = (vector float) { 0.0, dwdx, dwdy, dwdx + dwdy };
+ return spu_add(topLeftv, derivs);
+}
+
+
+/**
+ * Emit a quad (pass to next stage). No clipping is done.
+ * Note: about 1/5 to 1/7 of the time, mask is zero and this function
+ * should be skipped. But adding the test for that slows things down
+ * overall.
+ */
+static INLINE void
+emit_quad( int x, int y, mask_t mask)
+{
+ /* If any bits in mask are set... */
+ if (spu_extract(spu_orx(mask), 0)) {
+ const int ix = x - setup.cliprect_minx;
+ const int iy = y - setup.cliprect_miny;
+
+ spu.cur_ctile_status = TILE_STATUS_DIRTY;
+ spu.cur_ztile_status = TILE_STATUS_DIRTY;
+
+ {
+ /*
+ * Run fragment shader, execute per-fragment ops, update fb/tile.
+ */
+ vector float inputs[4*4], outputs[2*4];
+ vector float fragZ = eval_z((float) x, (float) y);
+ vector float fragW = eval_w((float) x, (float) y);
+ vector unsigned int kill_mask;
+
+ /* setup inputs */
+#if 0
+ eval_coeff_soa(1, (float) x, (float) y, fragW, inputs);
+#else
+ uint i;
+ for (i = 0; i < spu.vertex_info.num_attribs; i++) {
+ eval_coeff_soa(i+1, (float) x, (float) y, fragW, inputs + i * 4);
+ }
+#endif
+ ASSERT(spu.fragment_program);
+ ASSERT(spu.fragment_ops);
+
+ /* Execute the current fragment program */
+ kill_mask = spu.fragment_program(inputs, outputs, spu.constants);
+
+ mask = spu_andc(mask, kill_mask);
+
+ /* Execute per-fragment/quad operations, including:
+ * alpha test, z test, stencil test, blend and framebuffer writing.
+ * Note that there are two different fragment operations functions
+ * that can be called, one for front-facing fragments, and one
+ * for back-facing fragments. (Often the two are the same;
+ * but in some cases, like two-sided stenciling, they can be
+ * very different.) So choose the correct function depending
+ * on the calculated facing.
+ */
+ spu.fragment_ops[setup.facing](ix, iy, &spu.ctile, &spu.ztile,
+ fragZ,
+ outputs[0*4+0],
+ outputs[0*4+1],
+ outputs[0*4+2],
+ outputs[0*4+3],
+ mask);
+ }
+ }
+}
+
+
+/**
+ * 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.
+ * The mask is a uint4 vector and each element will be 0 or 0xffffffff.
+ */
+static INLINE mask_t
+calculate_mask(int x)
+{
+ /* This is a little tricky.
+ * Use & instead of && to avoid branches.
+ * Use negation to convert true/false to ~0/0 values.
+ */
+ mask_t mask;
+ mask = spu_insert(-((x >= setup.span.left[0]) & (x < setup.span.right[0])), mask, 0);
+ mask = spu_insert(-((x+1 >= setup.span.left[0]) & (x+1 < setup.span.right[0])), mask, 1);
+ mask = spu_insert(-((x >= setup.span.left[1]) & (x < setup.span.right[1])), mask, 2);
+ mask = spu_insert(-((x+1 >= setup.span.left[1]) & (x+1 < setup.span.right[1])), mask, 3);
+ return mask;
+}
+
+
+/**
+ * Render a horizontal span of quads
+ */
+static void
+flush_spans(void)
+{
+ 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;
+ }
+
+ /* OK, we're very likely to need the tile data now.
+ * clear or finish waiting if needed.
+ */
+ if (spu.cur_ctile_status == TILE_STATUS_GETTING) {
+ /* wait for mfc_get() to complete */
+ //printf("SPU: %u: waiting for ctile\n", spu.init.id);
+ wait_on_mask(1 << TAG_READ_TILE_COLOR);
+ spu.cur_ctile_status = TILE_STATUS_CLEAN;
+ }
+ else if (spu.cur_ctile_status == TILE_STATUS_CLEAR) {
+ //printf("SPU %u: clearing C tile %u, %u\n", spu.init.id, setup.tx, setup.ty);
+ clear_c_tile(&spu.ctile);
+ spu.cur_ctile_status = TILE_STATUS_DIRTY;
+ }
+ ASSERT(spu.cur_ctile_status != TILE_STATUS_DEFINED);
+
+ if (spu.read_depth_stencil) {
+ if (spu.cur_ztile_status == TILE_STATUS_GETTING) {
+ /* wait for mfc_get() to complete */
+ //printf("SPU: %u: waiting for ztile\n", spu.init.id);
+ wait_on_mask(1 << TAG_READ_TILE_Z);
+ spu.cur_ztile_status = TILE_STATUS_CLEAN;
+ }
+ else if (spu.cur_ztile_status == TILE_STATUS_CLEAR) {
+ //printf("SPU %u: clearing Z tile %u, %u\n", spu.init.id, setup.tx, setup.ty);
+ clear_z_tile(&spu.ztile);
+ spu.cur_ztile_status = TILE_STATUS_DIRTY;
+ }
+ ASSERT(spu.cur_ztile_status != TILE_STATUS_DEFINED);
+ }
+
+ /* 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( x, setup.span.y, calculate_mask( 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 vertex_header *v)
+{
+ uint i;
+ fprintf(stderr, " Vertex: (%p)\n", v);
+ for (i = 0; i < spu.vertex_info.num_attribs; i++) {
+ fprintf(stderr, " %d: %f %f %f %f\n", i,
+ spu_extract(v->data[i], 0),
+ spu_extract(v->data[i], 1),
+ spu_extract(v->data[i], 2),
+ spu_extract(v->data[i], 3));
+ }
+}
+#endif
+
+
+/**
+ * Sort vertices from top to bottom.
+ * Compute area and determine front vs. back facing.
+ * Do coarse clip test against tile bounds
+ * \return FALSE if tri is totally outside tile, TRUE otherwise
+ */
+static boolean
+setup_sort_vertices(const struct vertex_header *v0,
+ const struct vertex_header *v1,
+ const struct vertex_header *v2)
+{
+ float area, sign;
+
+#if DEBUG_VERTS
+ if (spu.init.id==0) {
+ fprintf(stderr, "SPU %u: Triangle:\n", spu.init.id);
+ print_vertex(v0);
+ print_vertex(v1);
+ print_vertex(v2);
+ }
+#endif
+
+ /* determine bottom to top order of vertices */
+ {
+ float y0 = spu_extract(v0->data[0], 1);
+ float y1 = spu_extract(v1->data[0], 1);
+ float y2 = spu_extract(v2->data[0], 1);
+ if (y0 <= y1) {
+ if (y1 <= y2) {
+ /* y0<=y1<=y2 */
+ setup.vmin = v0;
+ setup.vmid = v1;
+ setup.vmax = v2;
+ sign = -1.0f;
+ }
+ else if (y2 <= y0) {
+ /* y2<=y0<=y1 */
+ setup.vmin = v2;
+ setup.vmid = v0;
+ setup.vmax = v1;
+ sign = -1.0f;
+ }
+ else {
+ /* y0<=y2<=y1 */
+ setup.vmin = v0;
+ setup.vmid = v2;
+ setup.vmax = v1;
+ sign = 1.0f;
+ }
+ }
+ else {
+ if (y0 <= y2) {
+ /* y1<=y0<=y2 */
+ setup.vmin = v1;
+ setup.vmid = v0;
+ setup.vmax = v2;
+ sign = 1.0f;
+ }
+ else if (y2 <= y1) {
+ /* y2<=y1<=y0 */
+ setup.vmin = v2;
+ setup.vmid = v1;
+ setup.vmax = v0;
+ sign = 1.0f;
+ }
+ else {
+ /* y1<=y2<=y0 */
+ setup.vmin = v1;
+ setup.vmid = v2;
+ setup.vmax = v0;
+ sign = -1.0f;
+ }
+ }
+ }
+
+ /* Check if triangle is completely outside the tile bounds */
+ if (spu_extract(setup.vmin->data[0], 1) > setup.cliprect_maxy)
+ return FALSE;
+ if (spu_extract(setup.vmax->data[0], 1) < setup.cliprect_miny)
+ return FALSE;
+ if (spu_extract(setup.vmin->data[0], 0) < setup.cliprect_minx &&
+ spu_extract(setup.vmid->data[0], 0) < setup.cliprect_minx &&
+ spu_extract(setup.vmax->data[0], 0) < setup.cliprect_minx)
+ return FALSE;
+ if (spu_extract(setup.vmin->data[0], 0) > setup.cliprect_maxx &&
+ spu_extract(setup.vmid->data[0], 0) > setup.cliprect_maxx &&
+ spu_extract(setup.vmax->data[0], 0) > setup.cliprect_maxx)
+ return FALSE;
+
+ setup.ebot.dx = spu_extract(setup.vmid->data[0], 0) - spu_extract(setup.vmin->data[0], 0);
+ setup.ebot.dy = spu_extract(setup.vmid->data[0], 1) - spu_extract(setup.vmin->data[0], 1);
+ setup.emaj.dx = spu_extract(setup.vmax->data[0], 0) - spu_extract(setup.vmin->data[0], 0);
+ setup.emaj.dy = spu_extract(setup.vmax->data[0], 1) - spu_extract(setup.vmin->data[0], 1);
+ setup.etop.dx = spu_extract(setup.vmax->data[0], 0) - spu_extract(setup.vmid->data[0], 0);
+ setup.etop.dy = spu_extract(setup.vmax->data[0], 1) - spu_extract(setup.vmid->data[0], 1);
+
+ /*
+ * Compute triangle's area. Use 1/area to compute partial
+ * derivatives of attributes later.
+ */
+ area = setup.emaj.dx * setup.ebot.dy - setup.ebot.dx * setup.emaj.dy;
+
+ setup.oneOverArea = 1.0f / area;
+
+ /* The product of area * sign indicates front/back orientation (0/1).
+ * Just in case someone gets the bright idea of switching the front
+ * and back constants without noticing that we're assuming their
+ * values in this operation, also assert that the values are
+ * what we think they are.
+ */
+ ASSERT(CELL_FACING_FRONT == 0);
+ ASSERT(CELL_FACING_BACK == 1);
+ setup.facing = (area * sign > 0.0f)
+ ^ (spu.rasterizer.front_winding == PIPE_WINDING_CW);
+
+ setup.vprovoke = v2;
+
+ return TRUE;
+}
+
+
+/**
+ * Compute a0 for a constant-valued coefficient (GL_FLAT shading).
+ * The value value comes from vertex->data[slot].
+ * The result will be put into setup.coef[slot].a0.
+ * \param slot which attribute slot
+ */
+static INLINE void
+const_coeff4(uint slot)
+{
+ setup.coef[slot].dadx = (vector float) {0.0, 0.0, 0.0, 0.0};
+ setup.coef[slot].dady = (vector float) {0.0, 0.0, 0.0, 0.0};
+ setup.coef[slot].a0 = setup.vprovoke->data[slot];
+}
+
+
+/**
+ * As above, but interp setup all four vector components.
+ */
+static INLINE void
+tri_linear_coeff4(uint slot)
+{
+ const vector float vmin_d = setup.vmin->data[slot];
+ const vector float vmid_d = setup.vmid->data[slot];
+ const vector float vmax_d = setup.vmax->data[slot];
+ const vector float xxxx = spu_splats(spu_extract(setup.vmin->data[0], 0) - 0.5f);
+ const vector float yyyy = spu_splats(spu_extract(setup.vmin->data[0], 1) - 0.5f);
+
+ vector float botda = vmid_d - vmin_d;
+ vector float majda = vmax_d - vmin_d;
+
+ vector float a = spu_sub(spu_mul(spu_splats(setup.ebot.dy), majda),
+ spu_mul(botda, spu_splats(setup.emaj.dy)));
+ vector float b = spu_sub(spu_mul(spu_splats(setup.emaj.dx), botda),
+ spu_mul(majda, spu_splats(setup.ebot.dx)));
+
+ setup.coef[slot].dadx = spu_mul(a, spu_splats(setup.oneOverArea));
+ setup.coef[slot].dady = spu_mul(b, spu_splats(setup.oneOverArea));
+
+ vector float tempx = spu_mul(setup.coef[slot].dadx, xxxx);
+ vector float tempy = spu_mul(setup.coef[slot].dady, yyyy);
+
+ setup.coef[slot].a0 = spu_sub(vmin_d, spu_add(tempx, tempy));
+}
+
+
+/**
+ * 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_coeff4(uint slot)
+{
+ const vector float xxxx = spu_splats(spu_extract(setup.vmin->data[0], 0) - 0.5f);
+ const vector float yyyy = spu_splats(spu_extract(setup.vmin->data[0], 1) - 0.5f);
+
+ const vector float vmin_w = spu_splats(spu_extract(setup.vmin->data[0], 3));
+ const vector float vmid_w = spu_splats(spu_extract(setup.vmid->data[0], 3));
+ const vector float vmax_w = spu_splats(spu_extract(setup.vmax->data[0], 3));
+
+ vector float vmin_d = setup.vmin->data[slot];
+ vector float vmid_d = setup.vmid->data[slot];
+ vector float vmax_d = setup.vmax->data[slot];
+
+ vmin_d = spu_mul(vmin_d, vmin_w);
+ vmid_d = spu_mul(vmid_d, vmid_w);
+ vmax_d = spu_mul(vmax_d, vmax_w);
+
+ vector float botda = vmid_d - vmin_d;
+ vector float majda = vmax_d - vmin_d;
+
+ vector float a = spu_sub(spu_mul(spu_splats(setup.ebot.dy), majda),
+ spu_mul(botda, spu_splats(setup.emaj.dy)));
+ vector float b = spu_sub(spu_mul(spu_splats(setup.emaj.dx), botda),
+ spu_mul(majda, spu_splats(setup.ebot.dx)));
+
+ setup.coef[slot].dadx = spu_mul(a, spu_splats(setup.oneOverArea));
+ setup.coef[slot].dady = spu_mul(b, spu_splats(setup.oneOverArea));
+
+ vector float tempx = spu_mul(setup.coef[slot].dadx, xxxx);
+ vector float tempy = spu_mul(setup.coef[slot].dady, yyyy);
+
+ setup.coef[slot].a0 = spu_sub(vmin_d, spu_add(tempx, tempy));
+}
+
+
+
+/**
+ * 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(void)
+{
+ uint i;
+
+ for (i = 0; i < spu.vertex_info.num_attribs; i++) {
+ switch (spu.vertex_info.attrib[i].interp_mode) {
+ case INTERP_NONE:
+ break;
+ case INTERP_CONSTANT:
+ const_coeff4(i);
+ break;
+ case INTERP_POS:
+ /* fall-through */
+ case INTERP_LINEAR:
+ tri_linear_coeff4(i);
+ break;
+ case INTERP_PERSPECTIVE:
+ tri_persp_coeff4(i);
+ break;
+ default:
+ ASSERT(0);
+ }
+ }
+}
+
+
+static void
+setup_tri_edges(void)
+{
+ float vmin_x = spu_extract(setup.vmin->data[0], 0) + 0.5f;
+ float vmid_x = spu_extract(setup.vmid->data[0], 0) + 0.5f;
+
+ float vmin_y = spu_extract(setup.vmin->data[0], 1) - 0.5f;
+ float vmid_y = spu_extract(setup.vmid->data[0], 1) - 0.5f;
+ float vmax_y = spu_extract(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 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.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;
+}
+
+
+/**
+ * Draw triangle into tile at (tx, ty) (tile coords)
+ * The tile data should have already been fetched.
+ */
+boolean
+tri_draw(const float *v0, const float *v1, const float *v2,
+ uint tx, uint ty)
+{
+ 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;
+
+ if (!setup_sort_vertices((struct vertex_header *) v0,
+ (struct vertex_header *) v1,
+ (struct vertex_header *) v2)) {
+ return FALSE; /* totally clipped */
+ }
+
+ setup_tri_coefficients();
+ setup_tri_edges();
+
+ setup.span.y = 0;
+ setup.span.y_flags = 0;
+ setup.span.right[0] = 0;
+ setup.span.right[1] = 0;
+
+ if (setup.oneOverArea < 0.0) {
+ /* emaj on left */
+ subtriangle( &setup.emaj, &setup.ebot, setup.ebot.lines );
+ subtriangle( &setup.emaj, &setup.etop, setup.etop.lines );
+ }
+ else {
+ /* emaj on right */
+ subtriangle( &setup.ebot, &setup.emaj, setup.ebot.lines );
+ subtriangle( &setup.etop, &setup.emaj, setup.etop.lines );
+ }
+
+ flush_spans();
+
+ return TRUE;
+}