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/* $Id: s_aalinetemp.h,v 1.7 2001/03/12 00:48:41 gareth Exp $ */
/*
* Mesa 3-D graphics library
* Version: 3.5
*
* Copyright (C) 1999-2001 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 line template.
*/
/*
* Function to render each fragment in the AA line.
*/
static void
NAME(plot)(GLcontext *ctx, const struct LineInfo *line,
struct pixel_buffer *pb, int ix, int iy)
{
const GLfloat fx = (GLfloat) ix;
const GLfloat fy = (GLfloat) iy;
const GLfloat coverage = compute_coveragef(line, ix, iy);
GLdepth z;
GLfixed fog;
GLchan red, green, blue, alpha;
GLint frac, indx, index;
GLchan specRed, specGreen, specBlue;
GLfloat tex[MAX_TEXTURE_UNITS][4], lambda[MAX_TEXTURE_UNITS];
if (coverage == 0.0)
return;
/*
* Compute Z, color, texture coords, fog for the fragment by
* solving the plane equations at (ix,iy).
*/
#ifdef DO_Z
z = (GLdepth) solve_plane(fx, fy, line->zPlane);
#else
z = 0.0;
#endif
#ifdef DO_FOG
fog = FloatToFixed( solve_plane(fx, fy, line->fPlane) );
#else
fog = 0;
#endif
#ifdef DO_RGBA
red = solve_plane_chan(fx, fy, line->rPlane);
green = solve_plane_chan(fx, fy, line->gPlane);
blue = solve_plane_chan(fx, fy, line->bPlane);
alpha = (GLchan) (solve_plane_chan(fx, fy, line->aPlane) * coverage);;
#else
(void) red;
(void) green;
(void) blue;
(void) alpha;
#endif
#ifdef DO_INDEX
frac = (GLint) (15.0 * coverage);
indx = (GLint) solve_plane(fx, fy, line->iPlane);
index = (indx & ~0xf) | frac;
#else
(void) frac;
(void) indx;
(void) index;
#endif
#ifdef DO_SPEC
specRed = solve_plane_chan(fx, fy, line->srPlane);
specGreen = solve_plane_chan(fx, fy, line->sgPlane);
specBlue = solve_plane_chan(fx, fy, line->sbPlane);
#else
(void) specRed;
(void) specGreen;
(void) specBlue;
#endif
#ifdef DO_TEX
{
GLfloat invQ = solve_plane_recip(fx, fy, line->vPlane[0]);
tex[0][0] = solve_plane(fx, fy, line->sPlane[0]) * invQ;
tex[0][1] = solve_plane(fx, fy, line->tPlane[0]) * invQ;
tex[0][2] = solve_plane(fx, fy, line->uPlane[0]) * invQ;
lambda[0] = compute_lambda(line->sPlane[0], line->tPlane[0], invQ,
line->texWidth[0], line->texHeight[0]);
}
#elif defined(DO_MULTITEX)
{
GLuint unit;
for (unit = 0; unit < ctx->Const.MaxTextureUnits; unit++) {
if (ctx->Texture.Unit[unit]._ReallyEnabled) {
GLfloat invQ = solve_plane_recip(fx, fy, line->vPlane[unit]);
tex[unit][0] = solve_plane(fx, fy, line->sPlane[unit]) * invQ;
tex[unit][1] = solve_plane(fx, fy, line->tPlane[unit]) * invQ;
tex[unit][2] = solve_plane(fx, fy, line->uPlane[unit]) * invQ;
lambda[unit] = compute_lambda(line->sPlane[unit],
line->tPlane[unit], invQ,
line->texWidth[unit], line->texHeight[unit]);
}
}
}
#else
(void) tex[0][0];
(void) lambda[0];
#endif
#if defined(DO_MULTITEX)
#if defined(DO_SPEC)
PB_WRITE_MULTITEX_SPEC_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha,
specRed, specGreen, specBlue, tex);
#else
PB_WRITE_MULTITEX_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha, texcoords);
#endif
#elif defined(DO_TEX)
PB_WRITE_TEX_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha,
tex[0][0], tex[0][1], tex[0][2]);
#elif defined(DO_RGBA)
PB_WRITE_RGBA_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha);
#elif defined(DO_INDEX)
PB_WRITE_CI_PIXEL(pb, ix, iy, z, fog, index);
#endif
PB_CHECK_FLUSH(ctx, pb);
}
/*
* Line setup
*/
static void
NAME(line)(GLcontext *ctx, const SWvertex *v0, const SWvertex *v1)
{
SWcontext *swrast = SWRAST_CONTEXT(ctx);
struct pixel_buffer *pb = SWRAST_CONTEXT(ctx)->PB;
GLfloat tStart, tEnd; /* segment start, end along line length */
GLboolean inSegment;
GLint iLen, i;
/* Init the LineInfo struct */
struct LineInfo line;
line.x0 = v0->win[0];
line.y0 = v0->win[1];
line.x1 = v1->win[0];
line.y1 = v1->win[1];
line.dx = line.x1 - line.x0;
line.dy = line.y1 - line.y0;
line.len = sqrt(line.dx * line.dx + line.dy * line.dy);
line.halfWidth = 0.5F * ctx->Line.Width;
if (line.len == 0.0) {
line.xAdj = 0.0;
line.yAdj = 0.0;
}
else {
line.xAdj = line.dx / line.len * line.halfWidth;
line.yAdj = line.dy / line.len * line.halfWidth;
}
#ifdef DO_Z
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->win[2], v1->win[2], line.zPlane);
#endif
#ifdef DO_FOG
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->fog, v1->fog, line.fPlane);
#endif
#ifdef DO_RGBA
if (ctx->Light.ShadeModel == GL_SMOOTH) {
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->color[RCOMP], v1->color[RCOMP], line.rPlane);
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->color[GCOMP], v1->color[GCOMP], line.gPlane);
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->color[BCOMP], v1->color[BCOMP], line.bPlane);
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->color[ACOMP], v1->color[ACOMP], line.aPlane);
}
else {
constant_plane(v1->color[RCOMP], line.rPlane);
constant_plane(v1->color[GCOMP], line.gPlane);
constant_plane(v1->color[BCOMP], line.bPlane);
constant_plane(v1->color[ACOMP], line.aPlane);
}
#endif
#ifdef DO_SPEC
if (ctx->Light.ShadeModel == GL_SMOOTH) {
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->specular[RCOMP], v1->specular[RCOMP], line.srPlane);
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->specular[GCOMP], v1->specular[GCOMP], line.sgPlane);
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->specular[BCOMP], v1->specular[BCOMP], line.sbPlane);
}
else {
constant_plane(v1->specular[RCOMP], line.srPlane);
constant_plane(v1->specular[GCOMP], line.sgPlane);
constant_plane(v1->specular[BCOMP], line.sbPlane);
}
#endif
#ifdef DO_INDEX
if (ctx->Light.ShadeModel == GL_SMOOTH) {
compute_plane(line.x0, line.y0, line.x1, line.y1,
v0->index, v1->index, line.iPlane);
}
else {
constant_plane(v1->index, line.iPlane);
}
#endif
#ifdef DO_TEX
{
const struct gl_texture_object *obj = ctx->Texture.Unit[0]._Current;
const struct gl_texture_image *texImage = obj->Image[obj->BaseLevel];
const GLfloat invW0 = v0->win[3];
const GLfloat invW1 = v1->win[3];
const GLfloat s0 = v0->texcoord[0][0] * invW0;
const GLfloat s1 = v1->texcoord[0][0] * invW1;
const GLfloat t0 = v0->texcoord[0][1] * invW0;
const GLfloat t1 = v1->texcoord[0][1] * invW0;
const GLfloat r0 = v0->texcoord[0][2] * invW0;
const GLfloat r1 = v1->texcoord[0][2] * invW0;
const GLfloat q0 = v0->texcoord[0][3] * invW0;
const GLfloat q1 = v1->texcoord[0][3] * invW0;
compute_plane(line.x0, line.y0, line.x1, line.y1, s0, s1, line.sPlane[0]);
compute_plane(line.x0, line.y0, line.x1, line.y1, t0, t1, line.tPlane[0]);
compute_plane(line.x0, line.y0, line.x1, line.y1, r0, r1, line.uPlane[0]);
compute_plane(line.x0, line.y0, line.x1, line.y1, q0, q1, line.vPlane[0]);
line.texWidth[0] = (GLfloat) texImage->Width;
line.texHeight[0] = (GLfloat) texImage->Height;
}
#elif defined(DO_MULITEX)
{
GLuint u;
for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
if (ctx->Texture.Unit[u].ReallyEnabled) {
const struct gl_texture_object *obj = ctx->Texture.Unit[u].Current;
const struct gl_texture_image *texImage = obj->Image[obj->BaseLevel];
const GLfloat invW0 = v0->win[3];
const GLfloat invW1 = v1->win[3];
GLfloat (*texCoord)[4] = VB->TexCoordPtr[u]->data;
const GLfloat s0 = v0->texcoord[u][0] * invW0;
const GLfloat s1 = v1->texcoord[u][0] * invW1;
const GLfloat t0 = v0->texcoord[u][1] * invW0;
const GLfloat t1 = v1->texcoord[u][1] * invW0;
const GLfloat r0 = v0->texcoord[u][2] * invW0;
const GLfloat r1 = v1->texcoord[u][2] * invW0;
const GLfloat q0 = v0->texcoord[u][3] * invW0;
const GLfloat q1 = v1->texcoord[u][3] * invW0;
compute_plane(line.x0, line.y0, line.x1, line.y1, s0, s1, line.sPlane[u]);
compute_plane(line.x0, line.y0, line.x1, line.y1, t0, t1, line.tPlane[u]);
compute_plane(line.x0, line.y0, line.x1, line.y1, u0, u1, line.uPlane[u]);
compute_plane(line.x0, line.y0, line.x1, line.y1, v0, v1, line.vPlane[u]);
line.texWidth[u] = (GLfloat) texImage->Width;
line.texHeight[u] = (GLfloat) texImage->Height;
}
}
}
#endif
tStart = tEnd = 0.0;
inSegment = GL_FALSE;
iLen = (GLint) line.len;
if (ctx->Line.StippleFlag) {
for (i = 0; i < iLen; i++) {
const GLuint bit = (swrast->StippleCounter / ctx->Line.StippleFactor) & 0xf;
if ((1 << bit) & ctx->Line.StipplePattern) {
/* stipple bit is on */
const GLfloat t = (GLfloat) i / (GLfloat) line.len;
if (!inSegment) {
/* start new segment */
inSegment = GL_TRUE;
tStart = t;
}
else {
/* still in the segment, extend it */
tEnd = t;
}
}
else {
/* stipple bit is off */
if (inSegment && (tEnd > tStart)) {
/* draw the segment */
segment(ctx, &line, NAME(plot), pb, tStart, tEnd);
inSegment = GL_FALSE;
}
else {
/* still between segments, do nothing */
}
}
swrast->StippleCounter++;
}
if (inSegment) {
/* draw the final segment of the line */
segment(ctx, &line, NAME(plot), pb, tStart, 1.0F);
}
}
else {
/* non-stippled */
segment(ctx, &line, NAME(plot), pb, 0.0, 1.0);
}
}
#undef DO_Z
#undef DO_FOG
#undef DO_RGBA
#undef DO_INDEX
#undef DO_SPEC
#undef DO_TEX
#undef DO_MULTITEX
#undef NAME
|
