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-rw-r--r--nx-X11/extras/Mesa/src/mesa/swrast/s_aatriangle.c495
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diff --git a/nx-X11/extras/Mesa/src/mesa/swrast/s_aatriangle.c b/nx-X11/extras/Mesa/src/mesa/swrast/s_aatriangle.c
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index 000000000..5509f34c9
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+++ b/nx-X11/extras/Mesa/src/mesa/swrast/s_aatriangle.c
@@ -0,0 +1,495 @@
+/*
+ * Mesa 3-D graphics library
+ * Version: 6.3
+ *
+ * Copyright (C) 1999-2004 Brian Paul 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, sublicense,
+ * 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 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 NONINFRINGEMENT. IN NO EVENT SHALL
+ * BRIAN PAUL 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.
+ */
+
+
+/*
+ * Antialiased Triangle rasterizers
+ */
+
+
+#include "glheader.h"
+#include "context.h"
+#include "colormac.h"
+#include "context.h"
+#include "macros.h"
+#include "imports.h"
+#include "nvfragprog.h"
+#include "s_aatriangle.h"
+#include "s_context.h"
+#include "s_span.h"
+
+
+/*
+ * Compute coefficients of a plane using the X,Y coords of the v0, v1, v2
+ * vertices and the given Z values.
+ * A point (x,y,z) lies on plane iff a*x+b*y+c*z+d = 0.
+ */
+static INLINE void
+compute_plane(const GLfloat v0[], const GLfloat v1[], const GLfloat v2[],
+ GLfloat z0, GLfloat z1, GLfloat z2, GLfloat plane[4])
+{
+ const GLfloat px = v1[0] - v0[0];
+ const GLfloat py = v1[1] - v0[1];
+ const GLfloat pz = z1 - z0;
+
+ const GLfloat qx = v2[0] - v0[0];
+ const GLfloat qy = v2[1] - v0[1];
+ const GLfloat qz = z2 - z0;
+
+ /* Crossproduct "(a,b,c):= dv1 x dv2" is orthogonal to plane. */
+ const GLfloat a = py * qz - pz * qy;
+ const GLfloat b = pz * qx - px * qz;
+ const GLfloat c = px * qy - py * qx;
+ /* Point on the plane = "r*(a,b,c) + w", with fixed "r" depending
+ on the distance of plane from origin and arbitrary "w" parallel
+ to the plane. */
+ /* The scalar product "(r*(a,b,c)+w)*(a,b,c)" is "r*(a^2+b^2+c^2)",
+ which is equal to "-d" below. */
+ const GLfloat d = -(a * v0[0] + b * v0[1] + c * z0);
+
+ plane[0] = a;
+ plane[1] = b;
+ plane[2] = c;
+ plane[3] = d;
+}
+
+
+/*
+ * Compute coefficients of a plane with a constant Z value.
+ */
+static INLINE void
+constant_plane(GLfloat value, GLfloat plane[4])
+{
+ plane[0] = 0.0;
+ plane[1] = 0.0;
+ plane[2] = -1.0;
+ plane[3] = value;
+}
+
+#define CONSTANT_PLANE(VALUE, PLANE) \
+do { \
+ PLANE[0] = 0.0F; \
+ PLANE[1] = 0.0F; \
+ PLANE[2] = -1.0F; \
+ PLANE[3] = VALUE; \
+} while (0)
+
+
+
+/*
+ * Solve plane equation for Z at (X,Y).
+ */
+static INLINE GLfloat
+solve_plane(GLfloat x, GLfloat y, const GLfloat plane[4])
+{
+ ASSERT(plane[2] != 0.0F);
+ return (plane[3] + plane[0] * x + plane[1] * y) / -plane[2];
+}
+
+
+#define SOLVE_PLANE(X, Y, PLANE) \
+ ((PLANE[3] + PLANE[0] * (X) + PLANE[1] * (Y)) / -PLANE[2])
+
+
+/*
+ * Return 1 / solve_plane().
+ */
+static INLINE GLfloat
+solve_plane_recip(GLfloat x, GLfloat y, const GLfloat plane[4])
+{
+ const GLfloat denom = plane[3] + plane[0] * x + plane[1] * y;
+ if (denom == 0.0F)
+ return 0.0F;
+ else
+ return -plane[2] / denom;
+}
+
+
+/*
+ * Solve plane and return clamped GLchan value.
+ */
+static INLINE GLchan
+solve_plane_chan(GLfloat x, GLfloat y, const GLfloat plane[4])
+{
+ const GLfloat z = (plane[3] + plane[0] * x + plane[1] * y) / -plane[2];
+#if CHAN_TYPE == GL_FLOAT
+ return CLAMP(z, 0.0F, CHAN_MAXF);
+#else
+ if (z < 0)
+ return 0;
+ else if (z > CHAN_MAX)
+ return CHAN_MAX;
+ return (GLchan) IROUND_POS(z);
+#endif
+}
+
+
+
+/*
+ * Compute how much (area) of the given pixel is inside the triangle.
+ * Vertices MUST be specified in counter-clockwise order.
+ * Return: coverage in [0, 1].
+ */
+static GLfloat
+compute_coveragef(const GLfloat v0[3], const GLfloat v1[3],
+ const GLfloat v2[3], GLint winx, GLint winy)
+{
+ /* Given a position [0,3]x[0,3] return the sub-pixel sample position.
+ * Contributed by Ray Tice.
+ *
+ * Jitter sample positions -
+ * - average should be .5 in x & y for each column
+ * - each of the 16 rows and columns should be used once
+ * - the rectangle formed by the first four points
+ * should contain the other points
+ * - the distrubition should be fairly even in any given direction
+ *
+ * The pattern drawn below isn't optimal, but it's better than a regular
+ * grid. In the drawing, the center of each subpixel is surrounded by
+ * four dots. The "x" marks the jittered position relative to the
+ * subpixel center.
+ */
+#define POS(a, b) (0.5+a*4+b)/16
+ static const GLfloat samples[16][2] = {
+ /* start with the four corners */
+ { POS(0, 2), POS(0, 0) },
+ { POS(3, 3), POS(0, 2) },
+ { POS(0, 0), POS(3, 1) },
+ { POS(3, 1), POS(3, 3) },
+ /* continue with interior samples */
+ { POS(1, 1), POS(0, 1) },
+ { POS(2, 0), POS(0, 3) },
+ { POS(0, 3), POS(1, 3) },
+ { POS(1, 2), POS(1, 0) },
+ { POS(2, 3), POS(1, 2) },
+ { POS(3, 2), POS(1, 1) },
+ { POS(0, 1), POS(2, 2) },
+ { POS(1, 0), POS(2, 1) },
+ { POS(2, 1), POS(2, 3) },
+ { POS(3, 0), POS(2, 0) },
+ { POS(1, 3), POS(3, 0) },
+ { POS(2, 2), POS(3, 2) }
+ };
+
+ const GLfloat x = (GLfloat) winx;
+ const GLfloat y = (GLfloat) winy;
+ const GLfloat dx0 = v1[0] - v0[0];
+ const GLfloat dy0 = v1[1] - v0[1];
+ const GLfloat dx1 = v2[0] - v1[0];
+ const GLfloat dy1 = v2[1] - v1[1];
+ const GLfloat dx2 = v0[0] - v2[0];
+ const GLfloat dy2 = v0[1] - v2[1];
+ GLint stop = 4, i;
+ GLfloat insideCount = 16.0F;
+
+#ifdef DEBUG
+ {
+ const GLfloat area = dx0 * dy1 - dx1 * dy0;
+ ASSERT(area >= 0.0);
+ }
+#endif
+
+ for (i = 0; i < stop; i++) {
+ const GLfloat sx = x + samples[i][0];
+ const GLfloat sy = y + samples[i][1];
+ /* cross product determines if sample is inside or outside each edge */
+ GLfloat cross = (dx0 * (sy - v0[1]) - dy0 * (sx - v0[0]));
+ /* Check if the sample is exactly on an edge. If so, let cross be a
+ * positive or negative value depending on the direction of the edge.
+ */
+ if (cross == 0.0F)
+ cross = dx0 + dy0;
+ if (cross < 0.0F) {
+ /* sample point is outside first edge */
+ insideCount -= 1.0F;
+ stop = 16;
+ }
+ else {
+ /* sample point is inside first edge */
+ cross = (dx1 * (sy - v1[1]) - dy1 * (sx - v1[0]));
+ if (cross == 0.0F)
+ cross = dx1 + dy1;
+ if (cross < 0.0F) {
+ /* sample point is outside second edge */
+ insideCount -= 1.0F;
+ stop = 16;
+ }
+ else {
+ /* sample point is inside first and second edges */
+ cross = (dx2 * (sy - v2[1]) - dy2 * (sx - v2[0]));
+ if (cross == 0.0F)
+ cross = dx2 + dy2;
+ if (cross < 0.0F) {
+ /* sample point is outside third edge */
+ insideCount -= 1.0F;
+ stop = 16;
+ }
+ }
+ }
+ }
+ if (stop == 4)
+ return 1.0F;
+ else
+ return insideCount * (1.0F / 16.0F);
+}
+
+
+
+/*
+ * Compute how much (area) of the given pixel is inside the triangle.
+ * Vertices MUST be specified in counter-clockwise order.
+ * Return: coverage in [0, 15].
+ */
+static GLint
+compute_coveragei(const GLfloat v0[3], const GLfloat v1[3],
+ const GLfloat v2[3], GLint winx, GLint winy)
+{
+ /* NOTE: 15 samples instead of 16. */
+ static const GLfloat samples[15][2] = {
+ /* start with the four corners */
+ { POS(0, 2), POS(0, 0) },
+ { POS(3, 3), POS(0, 2) },
+ { POS(0, 0), POS(3, 1) },
+ { POS(3, 1), POS(3, 3) },
+ /* continue with interior samples */
+ { POS(1, 1), POS(0, 1) },
+ { POS(2, 0), POS(0, 3) },
+ { POS(0, 3), POS(1, 3) },
+ { POS(1, 2), POS(1, 0) },
+ { POS(2, 3), POS(1, 2) },
+ { POS(3, 2), POS(1, 1) },
+ { POS(0, 1), POS(2, 2) },
+ { POS(1, 0), POS(2, 1) },
+ { POS(2, 1), POS(2, 3) },
+ { POS(3, 0), POS(2, 0) },
+ { POS(1, 3), POS(3, 0) }
+ };
+ const GLfloat x = (GLfloat) winx;
+ const GLfloat y = (GLfloat) winy;
+ const GLfloat dx0 = v1[0] - v0[0];
+ const GLfloat dy0 = v1[1] - v0[1];
+ const GLfloat dx1 = v2[0] - v1[0];
+ const GLfloat dy1 = v2[1] - v1[1];
+ const GLfloat dx2 = v0[0] - v2[0];
+ const GLfloat dy2 = v0[1] - v2[1];
+ GLint stop = 4, i;
+ GLint insideCount = 15;
+
+#ifdef DEBUG
+ {
+ const GLfloat area = dx0 * dy1 - dx1 * dy0;
+ ASSERT(area >= 0.0);
+ }
+#endif
+
+ for (i = 0; i < stop; i++) {
+ const GLfloat sx = x + samples[i][0];
+ const GLfloat sy = y + samples[i][1];
+ const GLfloat fx0 = sx - v0[0];
+ const GLfloat fy0 = sy - v0[1];
+ const GLfloat fx1 = sx - v1[0];
+ const GLfloat fy1 = sy - v1[1];
+ const GLfloat fx2 = sx - v2[0];
+ const GLfloat fy2 = sy - v2[1];
+ /* cross product determines if sample is inside or outside each edge */
+ GLfloat cross0 = (dx0 * fy0 - dy0 * fx0);
+ GLfloat cross1 = (dx1 * fy1 - dy1 * fx1);
+ GLfloat cross2 = (dx2 * fy2 - dy2 * fx2);
+ /* Check if the sample is exactly on an edge. If so, let cross be a
+ * positive or negative value depending on the direction of the edge.
+ */
+ if (cross0 == 0.0F)
+ cross0 = dx0 + dy0;
+ if (cross1 == 0.0F)
+ cross1 = dx1 + dy1;
+ if (cross2 == 0.0F)
+ cross2 = dx2 + dy2;
+ if (cross0 < 0.0F || cross1 < 0.0F || cross2 < 0.0F) {
+ /* point is outside triangle */
+ insideCount--;
+ stop = 15;
+ }
+ }
+ if (stop == 4)
+ return 15;
+ else
+ return insideCount;
+}
+
+
+
+static void
+rgba_aa_tri(GLcontext *ctx,
+ const SWvertex *v0,
+ const SWvertex *v1,
+ const SWvertex *v2)
+{
+#define DO_Z
+#define DO_FOG
+#define DO_RGBA
+#include "s_aatritemp.h"
+}
+
+
+static void
+index_aa_tri(GLcontext *ctx,
+ const SWvertex *v0,
+ const SWvertex *v1,
+ const SWvertex *v2)
+{
+#define DO_Z
+#define DO_FOG
+#define DO_INDEX
+#include "s_aatritemp.h"
+}
+
+
+/*
+ * Compute mipmap level of detail.
+ * XXX we should really include the R coordinate in this computation
+ * in order to do 3-D texture mipmapping.
+ */
+static INLINE GLfloat
+compute_lambda(const GLfloat sPlane[4], const GLfloat tPlane[4],
+ const GLfloat qPlane[4], GLfloat cx, GLfloat cy,
+ GLfloat invQ, GLfloat texWidth, GLfloat texHeight)
+{
+ const GLfloat s = solve_plane(cx, cy, sPlane);
+ const GLfloat t = solve_plane(cx, cy, tPlane);
+ const GLfloat invQ_x1 = solve_plane_recip(cx+1.0F, cy, qPlane);
+ const GLfloat invQ_y1 = solve_plane_recip(cx, cy+1.0F, qPlane);
+ const GLfloat s_x1 = s - sPlane[0] / sPlane[2];
+ const GLfloat s_y1 = s - sPlane[1] / sPlane[2];
+ const GLfloat t_x1 = t - tPlane[0] / tPlane[2];
+ const GLfloat t_y1 = t - tPlane[1] / tPlane[2];
+ GLfloat dsdx = s_x1 * invQ_x1 - s * invQ;
+ GLfloat dsdy = s_y1 * invQ_y1 - s * invQ;
+ GLfloat dtdx = t_x1 * invQ_x1 - t * invQ;
+ GLfloat dtdy = t_y1 * invQ_y1 - t * invQ;
+ GLfloat maxU, maxV, rho, lambda;
+ dsdx = FABSF(dsdx);
+ dsdy = FABSF(dsdy);
+ dtdx = FABSF(dtdx);
+ dtdy = FABSF(dtdy);
+ maxU = MAX2(dsdx, dsdy) * texWidth;
+ maxV = MAX2(dtdx, dtdy) * texHeight;
+ rho = MAX2(maxU, maxV);
+ lambda = LOG2(rho);
+ return lambda;
+}
+
+
+static void
+tex_aa_tri(GLcontext *ctx,
+ const SWvertex *v0,
+ const SWvertex *v1,
+ const SWvertex *v2)
+{
+#define DO_Z
+#define DO_FOG
+#define DO_RGBA
+#define DO_TEX
+#include "s_aatritemp.h"
+}
+
+
+static void
+spec_tex_aa_tri(GLcontext *ctx,
+ const SWvertex *v0,
+ const SWvertex *v1,
+ const SWvertex *v2)
+{
+#define DO_Z
+#define DO_FOG
+#define DO_RGBA
+#define DO_TEX
+#define DO_SPEC
+#include "s_aatritemp.h"
+}
+
+
+static void
+multitex_aa_tri(GLcontext *ctx,
+ const SWvertex *v0,
+ const SWvertex *v1,
+ const SWvertex *v2)
+{
+#define DO_Z
+#define DO_FOG
+#define DO_RGBA
+#define DO_MULTITEX
+#include "s_aatritemp.h"
+}
+
+static void
+spec_multitex_aa_tri(GLcontext *ctx,
+ const SWvertex *v0,
+ const SWvertex *v1,
+ const SWvertex *v2)
+{
+#define DO_Z
+#define DO_FOG
+#define DO_RGBA
+#define DO_MULTITEX
+#define DO_SPEC
+#include "s_aatritemp.h"
+}
+
+
+/*
+ * Examine GL state and set swrast->Triangle to an
+ * appropriate antialiased triangle rasterizer function.
+ */
+void
+_swrast_set_aa_triangle_function(GLcontext *ctx)
+{
+ ASSERT(ctx->Polygon.SmoothFlag);
+
+ if (ctx->Texture._EnabledCoordUnits != 0) {
+ if (NEED_SECONDARY_COLOR(ctx)) {
+ if (ctx->Texture._EnabledCoordUnits > 1) {
+ SWRAST_CONTEXT(ctx)->Triangle = spec_multitex_aa_tri;
+ }
+ else {
+ SWRAST_CONTEXT(ctx)->Triangle = spec_tex_aa_tri;
+ }
+ }
+ else {
+ if (ctx->Texture._EnabledCoordUnits > 1) {
+ SWRAST_CONTEXT(ctx)->Triangle = multitex_aa_tri;
+ }
+ else {
+ SWRAST_CONTEXT(ctx)->Triangle = tex_aa_tri;
+ }
+ }
+ }
+ else if (ctx->Visual.rgbMode) {
+ SWRAST_CONTEXT(ctx)->Triangle = rgba_aa_tri;
+ }
+ else {
+ SWRAST_CONTEXT(ctx)->Triangle = index_aa_tri;
+ }
+
+ ASSERT(SWRAST_CONTEXT(ctx)->Triangle);
+}
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