diff options
Diffstat (limited to 'mesalib/src/mesa/swrast/s_aatriangle.c')
-rw-r--r-- | mesalib/src/mesa/swrast/s_aatriangle.c | 624 |
1 files changed, 312 insertions, 312 deletions
diff --git a/mesalib/src/mesa/swrast/s_aatriangle.c b/mesalib/src/mesa/swrast/s_aatriangle.c index ad068d0c0..c68fdf63b 100644 --- a/mesalib/src/mesa/swrast/s_aatriangle.c +++ b/mesalib/src/mesa/swrast/s_aatriangle.c @@ -1,312 +1,312 @@ -/*
- * Mesa 3-D graphics library
- * Version: 6.5.3
- *
- * Copyright (C) 1999-2007 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 "main/glheader.h"
-#include "main/context.h"
-#include "main/colormac.h"
-#include "main/macros.h"
-#include "main/imports.h"
-#include "main/state.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
-}
-
-
-static INLINE GLfloat
-plane_dx(const GLfloat plane[4])
-{
- return -plane[0] / plane[2];
-}
-
-static INLINE GLfloat
-plane_dy(const GLfloat plane[4])
-{
- return -plane[1] / plane[2];
-}
-
-
-
-/*
- * 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;
-
- ASSERT(dx0 * dy1 - dx1 * dy0 >= 0.0); /* area >= 0.0 */
-
- 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);
-}
-
-
-
-static void
-rgba_aa_tri(struct gl_context *ctx,
- const SWvertex *v0,
- const SWvertex *v1,
- const SWvertex *v2)
-{
-#define DO_Z
-#include "s_aatritemp.h"
-}
-
-
-static void
-general_aa_tri(struct gl_context *ctx,
- const SWvertex *v0,
- const SWvertex *v1,
- const SWvertex *v2)
-{
-#define DO_Z
-#define DO_ATTRIBS
-#include "s_aatritemp.h"
-}
-
-
-
-/*
- * Examine GL state and set swrast->Triangle to an
- * appropriate antialiased triangle rasterizer function.
- */
-void
-_swrast_set_aa_triangle_function(struct gl_context *ctx)
-{
- SWcontext *swrast = SWRAST_CONTEXT(ctx);
-
- ASSERT(ctx->Polygon.SmoothFlag);
-
- if (ctx->Texture._EnabledCoordUnits != 0
- || ctx->FragmentProgram._Current
- || swrast->_FogEnabled
- || _mesa_need_secondary_color(ctx)) {
- SWRAST_CONTEXT(ctx)->Triangle = general_aa_tri;
- }
- else {
- SWRAST_CONTEXT(ctx)->Triangle = rgba_aa_tri;
- }
-
- ASSERT(SWRAST_CONTEXT(ctx)->Triangle);
-}
+/* + * Mesa 3-D graphics library + * Version: 6.5.3 + * + * Copyright (C) 1999-2007 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 "main/glheader.h" +#include "main/context.h" +#include "main/colormac.h" +#include "main/macros.h" +#include "main/imports.h" +#include "main/state.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 +} + + +static inline GLfloat +plane_dx(const GLfloat plane[4]) +{ + return -plane[0] / plane[2]; +} + +static inline GLfloat +plane_dy(const GLfloat plane[4]) +{ + return -plane[1] / plane[2]; +} + + + +/* + * 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; + + ASSERT(dx0 * dy1 - dx1 * dy0 >= 0.0); /* area >= 0.0 */ + + 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); +} + + + +static void +rgba_aa_tri(struct gl_context *ctx, + const SWvertex *v0, + const SWvertex *v1, + const SWvertex *v2) +{ +#define DO_Z +#include "s_aatritemp.h" +} + + +static void +general_aa_tri(struct gl_context *ctx, + const SWvertex *v0, + const SWvertex *v1, + const SWvertex *v2) +{ +#define DO_Z +#define DO_ATTRIBS +#include "s_aatritemp.h" +} + + + +/* + * Examine GL state and set swrast->Triangle to an + * appropriate antialiased triangle rasterizer function. + */ +void +_swrast_set_aa_triangle_function(struct gl_context *ctx) +{ + SWcontext *swrast = SWRAST_CONTEXT(ctx); + + ASSERT(ctx->Polygon.SmoothFlag); + + if (ctx->Texture._EnabledCoordUnits != 0 + || ctx->FragmentProgram._Current + || swrast->_FogEnabled + || _mesa_need_secondary_color(ctx)) { + SWRAST_CONTEXT(ctx)->Triangle = general_aa_tri; + } + else { + SWRAST_CONTEXT(ctx)->Triangle = rgba_aa_tri; + } + + ASSERT(SWRAST_CONTEXT(ctx)->Triangle); +} |