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author | marha <marha@users.sourceforge.net> | 2009-10-09 06:31:44 +0000 |
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committer | marha <marha@users.sourceforge.net> | 2009-10-09 06:31:44 +0000 |
commit | 06456f5db88b434c3634ede42bdbfdce78fc4249 (patch) | |
tree | 97f5174e2d3da40faee7f2ad8858233da3d0166e /mesalib/src/mesa/swrast/s_aaline.c | |
parent | 7b230a3fe2d6c83488d9eec43067fe8ba8ac081b (diff) | |
parent | a0c4815433ccd57322f4f7703ca35e9ccfa59250 (diff) | |
download | vcxsrv-06456f5db88b434c3634ede42bdbfdce78fc4249.tar.gz vcxsrv-06456f5db88b434c3634ede42bdbfdce78fc4249.tar.bz2 vcxsrv-06456f5db88b434c3634ede42bdbfdce78fc4249.zip |
svn merge ^/branches/released . --username marha
Diffstat (limited to 'mesalib/src/mesa/swrast/s_aaline.c')
-rw-r--r-- | mesalib/src/mesa/swrast/s_aaline.c | 524 |
1 files changed, 524 insertions, 0 deletions
diff --git a/mesalib/src/mesa/swrast/s_aaline.c b/mesalib/src/mesa/swrast/s_aaline.c new file mode 100644 index 000000000..9bfa8f2e6 --- /dev/null +++ b/mesalib/src/mesa/swrast/s_aaline.c @@ -0,0 +1,524 @@ +/* + * 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. + */ + + +#include "main/glheader.h" +#include "main/imports.h" +#include "main/macros.h" +#include "main/mtypes.h" +#include "swrast/s_aaline.h" +#include "swrast/s_context.h" +#include "swrast/s_span.h" +#include "swrast/swrast.h" + + +#define SUB_PIXEL 4 + + +/* + * Info about the AA line we're rendering + */ +struct LineInfo +{ + GLfloat x0, y0; /* start */ + GLfloat x1, y1; /* end */ + GLfloat dx, dy; /* direction vector */ + GLfloat len; /* length */ + GLfloat halfWidth; /* half of line width */ + GLfloat xAdj, yAdj; /* X and Y adjustment for quad corners around line */ + /* for coverage computation */ + GLfloat qx0, qy0; /* quad vertices */ + GLfloat qx1, qy1; + GLfloat qx2, qy2; + GLfloat qx3, qy3; + GLfloat ex0, ey0; /* quad edge vectors */ + GLfloat ex1, ey1; + GLfloat ex2, ey2; + GLfloat ex3, ey3; + + /* DO_Z */ + GLfloat zPlane[4]; + /* DO_RGBA */ + GLfloat rPlane[4], gPlane[4], bPlane[4], aPlane[4]; + /* DO_INDEX */ + GLfloat iPlane[4]; + /* DO_ATTRIBS */ + GLfloat wPlane[4]; + GLfloat attrPlane[FRAG_ATTRIB_MAX][4][4]; + GLfloat lambda[FRAG_ATTRIB_MAX]; + GLfloat texWidth[FRAG_ATTRIB_MAX]; + GLfloat texHeight[FRAG_ATTRIB_MAX]; + + SWspan span; +}; + + + +/* + * Compute the equation of a plane used to interpolate line fragment data + * such as color, Z, texture coords, etc. + * Input: (x0, y0) and (x1,y1) are the endpoints of the line. + * z0, and z1 are the end point values to interpolate. + * Output: plane - the plane equation. + * + * Note: we don't really have enough parameters to specify a plane. + * We take the endpoints of the line and compute a plane such that + * the cross product of the line vector and the plane normal is + * parallel to the projection plane. + */ +static void +compute_plane(GLfloat x0, GLfloat y0, GLfloat x1, GLfloat y1, + GLfloat z0, GLfloat z1, GLfloat plane[4]) +{ +#if 0 + /* original */ + const GLfloat px = x1 - x0; + const GLfloat py = y1 - y0; + const GLfloat pz = z1 - z0; + const GLfloat qx = -py; + const GLfloat qy = px; + const GLfloat qz = 0; + const GLfloat a = py * qz - pz * qy; + const GLfloat b = pz * qx - px * qz; + const GLfloat c = px * qy - py * qx; + const GLfloat d = -(a * x0 + b * y0 + c * z0); + plane[0] = a; + plane[1] = b; + plane[2] = c; + plane[3] = d; +#else + /* simplified */ + const GLfloat px = x1 - x0; + const GLfloat py = y1 - y0; + const GLfloat pz = z0 - z1; + const GLfloat a = pz * px; + const GLfloat b = pz * py; + const GLfloat c = px * px + py * py; + const GLfloat d = -(a * x0 + b * y0 + c * z0); + if (a == 0.0 && b == 0.0 && c == 0.0 && d == 0.0) { + plane[0] = 0.0; + plane[1] = 0.0; + plane[2] = 1.0; + plane[3] = 0.0; + } + else { + plane[0] = a; + plane[1] = b; + plane[2] = c; + plane[3] = d; + } +#endif +} + + +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; +} + + +static INLINE GLfloat +solve_plane(GLfloat x, GLfloat y, const GLfloat plane[4]) +{ + const GLfloat z = (plane[3] + plane[0] * x + plane[1] * y) / -plane[2]; + return z; +} + +#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 == 0.0) + return 0.0; + 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 mipmap level of detail. + */ +static INLINE GLfloat +compute_lambda(const GLfloat sPlane[4], const GLfloat tPlane[4], + GLfloat invQ, GLfloat width, GLfloat height) +{ + GLfloat dudx = sPlane[0] / sPlane[2] * invQ * width; + GLfloat dudy = sPlane[1] / sPlane[2] * invQ * width; + GLfloat dvdx = tPlane[0] / tPlane[2] * invQ * height; + GLfloat dvdy = tPlane[1] / tPlane[2] * invQ * height; + GLfloat r1 = dudx * dudx + dudy * dudy; + GLfloat r2 = dvdx * dvdx + dvdy * dvdy; + GLfloat rho2 = r1 + r2; + /* return log base 2 of rho */ + if (rho2 == 0.0F) + return 0.0; + else + return (GLfloat) (LOGF(rho2) * 1.442695 * 0.5);/* 1.442695 = 1/log(2) */ +} + + + + +/* + * Fill in the samples[] array with the (x,y) subpixel positions of + * xSamples * ySamples sample positions. + * Note that the four corner samples are put into the first four + * positions of the array. This allows us to optimize for the common + * case of all samples being inside the polygon. + */ +static void +make_sample_table(GLint xSamples, GLint ySamples, GLfloat samples[][2]) +{ + const GLfloat dx = 1.0F / (GLfloat) xSamples; + const GLfloat dy = 1.0F / (GLfloat) ySamples; + GLint x, y; + GLint i; + + i = 4; + for (x = 0; x < xSamples; x++) { + for (y = 0; y < ySamples; y++) { + GLint j; + if (x == 0 && y == 0) { + /* lower left */ + j = 0; + } + else if (x == xSamples - 1 && y == 0) { + /* lower right */ + j = 1; + } + else if (x == 0 && y == ySamples - 1) { + /* upper left */ + j = 2; + } + else if (x == xSamples - 1 && y == ySamples - 1) { + /* upper right */ + j = 3; + } + else { + j = i++; + } + samples[j][0] = x * dx + 0.5F * dx; + samples[j][1] = y * dy + 0.5F * dy; + } + } +} + + + +/* + * Compute how much of the given pixel's area is inside the rectangle + * defined by vertices v0, v1, v2, v3. + * Vertices MUST be specified in counter-clockwise order. + * Return: coverage in [0, 1]. + */ +static GLfloat +compute_coveragef(const struct LineInfo *info, + GLint winx, GLint winy) +{ + static GLfloat samples[SUB_PIXEL * SUB_PIXEL][2]; + static GLboolean haveSamples = GL_FALSE; + const GLfloat x = (GLfloat) winx; + const GLfloat y = (GLfloat) winy; + GLint stop = 4, i; + GLfloat insideCount = SUB_PIXEL * SUB_PIXEL; + + if (!haveSamples) { + make_sample_table(SUB_PIXEL, SUB_PIXEL, samples); + haveSamples = GL_TRUE; + } + +#if 0 /*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 - info->qx0; + const GLfloat fy0 = sy - info->qy0; + const GLfloat fx1 = sx - info->qx1; + const GLfloat fy1 = sy - info->qy1; + const GLfloat fx2 = sx - info->qx2; + const GLfloat fy2 = sy - info->qy2; + const GLfloat fx3 = sx - info->qx3; + const GLfloat fy3 = sy - info->qy3; + /* cross product determines if sample is inside or outside each edge */ + GLfloat cross0 = (info->ex0 * fy0 - info->ey0 * fx0); + GLfloat cross1 = (info->ex1 * fy1 - info->ey1 * fx1); + GLfloat cross2 = (info->ex2 * fy2 - info->ey2 * fx2); + GLfloat cross3 = (info->ex3 * fy3 - info->ey3 * fx3); + /* 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 = info->ex0 + info->ey0; + if (cross1 == 0.0F) + cross1 = info->ex1 + info->ey1; + if (cross2 == 0.0F) + cross2 = info->ex2 + info->ey2; + if (cross3 == 0.0F) + cross3 = info->ex3 + info->ey3; + if (cross0 < 0.0F || cross1 < 0.0F || cross2 < 0.0F || cross3 < 0.0F) { + /* point is outside quadrilateral */ + insideCount -= 1.0F; + stop = SUB_PIXEL * SUB_PIXEL; + } + } + if (stop == 4) + return 1.0F; + else + return insideCount * (1.0F / (SUB_PIXEL * SUB_PIXEL)); +} + + +/** + * Compute coverage value for color index mode. + * XXX this may not be quite correct. + * \return coverage in [0,15]. + */ +static GLfloat +compute_coveragei(const struct LineInfo *info, + GLint winx, GLint winy) +{ + return compute_coveragef(info, winx, winy) * 15.0F; +} + + + +typedef void (*plot_func)(GLcontext *ctx, struct LineInfo *line, + int ix, int iy); + + + +/* + * Draw an AA line segment (called many times per line when stippling) + */ +static void +segment(GLcontext *ctx, + struct LineInfo *line, + plot_func plot, + GLfloat t0, GLfloat t1) +{ + const GLfloat absDx = (line->dx < 0.0F) ? -line->dx : line->dx; + const GLfloat absDy = (line->dy < 0.0F) ? -line->dy : line->dy; + /* compute the actual segment's endpoints */ + const GLfloat x0 = line->x0 + t0 * line->dx; + const GLfloat y0 = line->y0 + t0 * line->dy; + const GLfloat x1 = line->x0 + t1 * line->dx; + const GLfloat y1 = line->y0 + t1 * line->dy; + + /* compute vertices of the line-aligned quadrilateral */ + line->qx0 = x0 - line->yAdj; + line->qy0 = y0 + line->xAdj; + line->qx1 = x0 + line->yAdj; + line->qy1 = y0 - line->xAdj; + line->qx2 = x1 + line->yAdj; + line->qy2 = y1 - line->xAdj; + line->qx3 = x1 - line->yAdj; + line->qy3 = y1 + line->xAdj; + /* compute the quad's edge vectors (for coverage calc) */ + line->ex0 = line->qx1 - line->qx0; + line->ey0 = line->qy1 - line->qy0; + line->ex1 = line->qx2 - line->qx1; + line->ey1 = line->qy2 - line->qy1; + line->ex2 = line->qx3 - line->qx2; + line->ey2 = line->qy3 - line->qy2; + line->ex3 = line->qx0 - line->qx3; + line->ey3 = line->qy0 - line->qy3; + + if (absDx > absDy) { + /* X-major line */ + GLfloat dydx = line->dy / line->dx; + GLfloat xLeft, xRight, yBot, yTop; + GLint ix, ixRight; + if (x0 < x1) { + xLeft = x0 - line->halfWidth; + xRight = x1 + line->halfWidth; + if (line->dy >= 0.0) { + yBot = y0 - 3.0F * line->halfWidth; + yTop = y0 + line->halfWidth; + } + else { + yBot = y0 - line->halfWidth; + yTop = y0 + 3.0F * line->halfWidth; + } + } + else { + xLeft = x1 - line->halfWidth; + xRight = x0 + line->halfWidth; + if (line->dy <= 0.0) { + yBot = y1 - 3.0F * line->halfWidth; + yTop = y1 + line->halfWidth; + } + else { + yBot = y1 - line->halfWidth; + yTop = y1 + 3.0F * line->halfWidth; + } + } + + /* scan along the line, left-to-right */ + ixRight = (GLint) (xRight + 1.0F); + + /*printf("avg span height: %g\n", yTop - yBot);*/ + for (ix = (GLint) xLeft; ix < ixRight; ix++) { + const GLint iyBot = (GLint) yBot; + const GLint iyTop = (GLint) (yTop + 1.0F); + GLint iy; + /* scan across the line, bottom-to-top */ + for (iy = iyBot; iy < iyTop; iy++) { + (*plot)(ctx, line, ix, iy); + } + yBot += dydx; + yTop += dydx; + } + } + else { + /* Y-major line */ + GLfloat dxdy = line->dx / line->dy; + GLfloat yBot, yTop, xLeft, xRight; + GLint iy, iyTop; + if (y0 < y1) { + yBot = y0 - line->halfWidth; + yTop = y1 + line->halfWidth; + if (line->dx >= 0.0) { + xLeft = x0 - 3.0F * line->halfWidth; + xRight = x0 + line->halfWidth; + } + else { + xLeft = x0 - line->halfWidth; + xRight = x0 + 3.0F * line->halfWidth; + } + } + else { + yBot = y1 - line->halfWidth; + yTop = y0 + line->halfWidth; + if (line->dx <= 0.0) { + xLeft = x1 - 3.0F * line->halfWidth; + xRight = x1 + line->halfWidth; + } + else { + xLeft = x1 - line->halfWidth; + xRight = x1 + 3.0F * line->halfWidth; + } + } + + /* scan along the line, bottom-to-top */ + iyTop = (GLint) (yTop + 1.0F); + + /*printf("avg span width: %g\n", xRight - xLeft);*/ + for (iy = (GLint) yBot; iy < iyTop; iy++) { + const GLint ixLeft = (GLint) xLeft; + const GLint ixRight = (GLint) (xRight + 1.0F); + GLint ix; + /* scan across the line, left-to-right */ + for (ix = ixLeft; ix < ixRight; ix++) { + (*plot)(ctx, line, ix, iy); + } + xLeft += dxdy; + xRight += dxdy; + } + } +} + + +#define NAME(x) aa_ci_##x +#define DO_Z +#define DO_ATTRIBS /* for fog */ +#define DO_INDEX +#include "s_aalinetemp.h" + + +#define NAME(x) aa_rgba_##x +#define DO_Z +#define DO_RGBA +#include "s_aalinetemp.h" + + +#define NAME(x) aa_general_rgba_##x +#define DO_Z +#define DO_RGBA +#define DO_ATTRIBS +#include "s_aalinetemp.h" + + + +void +_swrast_choose_aa_line_function(GLcontext *ctx) +{ + SWcontext *swrast = SWRAST_CONTEXT(ctx); + + ASSERT(ctx->Line.SmoothFlag); + + if (ctx->Visual.rgbMode) { + /* RGBA */ + if (ctx->Texture._EnabledCoordUnits != 0 + || ctx->FragmentProgram._Current + || (ctx->Light.Enabled && + ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR) + || ctx->Fog.ColorSumEnabled + || swrast->_FogEnabled) { + swrast->Line = aa_general_rgba_line; + } + else { + swrast->Line = aa_rgba_line; + } + } + else { + /* Color Index */ + swrast->Line = aa_ci_line; + } +} |