src/mesa/swrast/s_aalinetemp.h

   1 /* $Id: s_aalinetemp.h,v 1.10 2001/05/15 21:30:26 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.5
   6  *
   7  * Copyright (C) 1999-2001  Brian Paul   All Rights Reserved.
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a
  10  * copy of this software and associated documentation files (the "Software"),
  11  * to deal in the Software without restriction, including without limitation
  12  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  13  * and/or sell copies of the Software, and to permit persons to whom the
  14  * Software is furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included
  17  * in all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  22  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  23  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  24  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  */
  26
  27
  28 /*
  29  * Antialiased line template.
  30  */
  31
  32
  33 /*
  34  * Function to render each fragment in the AA line.
  35  */
  36 static void
  37 NAME(plot)(GLcontext *ctx, const struct LineInfo *line,
  38            struct pixel_buffer *pb, int ix, int iy)
  39 {
  40    const GLfloat fx = (GLfloat) ix;
  41    const GLfloat fy = (GLfloat) iy;
  42    const GLfloat coverage = compute_coveragef(line, ix, iy);
  43    GLdepth z;
  44    GLfloat fog;
  45 #ifdef DO_RGBA
  46    GLchan red, green, blue, alpha;
  47 #else
  48    GLint index;
  49 #endif
  50    GLchan specRed, specGreen, specBlue;
  51    GLfloat tex[MAX_TEXTURE_UNITS][4], lambda[MAX_TEXTURE_UNITS];
  52
  53    if (coverage == 0.0)
  54       return;
  55
  56    /*
  57     * Compute Z, color, texture coords, fog for the fragment by
  58     * solving the plane equations at (ix,iy).
  59     */
  60 #ifdef DO_Z
  61    z = (GLdepth) solve_plane(fx, fy, line->zPlane);
  62 #else
  63    z = 0.0;
  64 #endif
  65 #ifdef DO_FOG
  66    fog = solve_plane(fx, fy, line->fPlane);
  67 #else
  68    fog = 0.0;
  69 #endif
  70 #ifdef DO_RGBA
  71    red   = solve_plane_chan(fx, fy, line->rPlane);
  72    green = solve_plane_chan(fx, fy, line->gPlane);
  73    blue  = solve_plane_chan(fx, fy, line->bPlane);
  74    alpha = solve_plane_chan(fx, fy, line->aPlane);
  75 #endif
  76 #ifdef DO_INDEX
  77    index = (GLint) solve_plane(fx, fy, line->iPlane);
  78 #else
  79    (void) index;
  80 #endif
  81 #ifdef DO_SPEC
  82    specRed   = solve_plane_chan(fx, fy, line->srPlane);
  83    specGreen = solve_plane_chan(fx, fy, line->sgPlane);
  84    specBlue  = solve_plane_chan(fx, fy, line->sbPlane);
  85 #else
  86    (void) specRed;
  87    (void) specGreen;
  88    (void) specBlue;
  89 #endif
  90 #ifdef DO_TEX
  91    {
  92       GLfloat invQ = solve_plane_recip(fx, fy, line->vPlane[0]);
  93       tex[0][0] = solve_plane(fx, fy, line->sPlane[0]) * invQ;
  94       tex[0][1] = solve_plane(fx, fy, line->tPlane[0]) * invQ;
  95       tex[0][2] = solve_plane(fx, fy, line->uPlane[0]) * invQ;
  96       lambda[0] = compute_lambda(line->sPlane[0], line->tPlane[0], invQ,
  97                                  line->texWidth[0], line->texHeight[0]);
  98    }
  99 #elif defined(DO_MULTITEX)
 100    {
 101       GLuint unit;
 102       for (unit = 0; unit < ctx->Const.MaxTextureUnits; unit++) {
 103          if (ctx->Texture.Unit[unit]._ReallyEnabled) {
 104             GLfloat invQ = solve_plane_recip(fx, fy, line->vPlane[unit]);
 105             tex[unit][0] = solve_plane(fx, fy, line->sPlane[unit]) * invQ;
 106             tex[unit][1] = solve_plane(fx, fy, line->tPlane[unit]) * invQ;
 107             tex[unit][2] = solve_plane(fx, fy, line->uPlane[unit]) * invQ;
 108             lambda[unit] = compute_lambda(line->sPlane[unit],
 109                                           line->tPlane[unit], invQ,
 110                                           line->texWidth[unit], line->texHeight[unit]);
 111          }
 112       }
 113    }
 114 #else
 115    (void) tex[0][0];
 116    (void) lambda[0];
 117 #endif
 118
 119
 120    PB_COVERAGE(pb, coverage);
 121
 122 #if defined(DO_MULTITEX)
 123 #if defined(DO_SPEC)
 124    PB_WRITE_MULTITEX_SPEC_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha,
 125                                 specRed, specGreen, specBlue, tex);
 126 #else
 127    PB_WRITE_MULTITEX_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha, texcoords);
 128 #endif
 129 #elif defined(DO_TEX)
 130    PB_WRITE_TEX_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha,
 131                       tex[0][0], tex[0][1], tex[0][2]);
 132 #elif defined(DO_RGBA)
 133    PB_WRITE_RGBA_PIXEL(pb, ix, iy, z, fog, red, green, blue, alpha);
 134 #elif defined(DO_INDEX)
 135    PB_WRITE_CI_PIXEL(pb, ix, iy, z, fog, index);
 136 #endif
 137
 138    pb->haveCoverage = GL_TRUE;
 139    PB_CHECK_FLUSH(ctx, pb);
 140 }
 141
 142
 143
 144 /*
 145  * Line setup
 146  */
 147 static void
 148 NAME(line)(GLcontext *ctx, const SWvertex *v0, const SWvertex *v1)
 149 {
 150    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 151    struct pixel_buffer *pb = SWRAST_CONTEXT(ctx)->PB;
 152    GLfloat tStart, tEnd;   /* segment start, end along line length */
 153    GLboolean inSegment;
 154    GLint iLen, i;
 155
 156    /* Init the LineInfo struct */
 157    struct LineInfo line;
 158    line.x0 = v0->win[0];
 159    line.y0 = v0->win[1];
 160    line.x1 = v1->win[0];
 161    line.y1 = v1->win[1];
 162    line.dx = line.x1 - line.x0;
 163    line.dy = line.y1 - line.y0;
 164    line.len = sqrt(line.dx * line.dx + line.dy * line.dy);
 165    line.halfWidth = 0.5F * ctx->Line.Width;
 166
 167    if (line.len == 0.0)
 168       return;
 169
 170    line.xAdj = line.dx / line.len * line.halfWidth;
 171    line.yAdj = line.dy / line.len * line.halfWidth;
 172
 173 #ifdef DO_Z
 174    compute_plane(line.x0, line.y0, line.x1, line.y1,
 175                  v0->win[2], v1->win[2], line.zPlane);
 176 #endif
 177 #ifdef DO_FOG
 178    compute_plane(line.x0, line.y0, line.x1, line.y1,
 179                  v0->fog, v1->fog, line.fPlane);
 180 #endif
 181 #ifdef DO_RGBA
 182    if (ctx->Light.ShadeModel == GL_SMOOTH) {
 183       compute_plane(line.x0, line.y0, line.x1, line.y1,
 184                     v0->color[RCOMP], v1->color[RCOMP], line.rPlane);
 185       compute_plane(line.x0, line.y0, line.x1, line.y1,
 186                     v0->color[GCOMP], v1->color[GCOMP], line.gPlane);
 187       compute_plane(line.x0, line.y0, line.x1, line.y1,
 188                     v0->color[BCOMP], v1->color[BCOMP], line.bPlane);
 189       compute_plane(line.x0, line.y0, line.x1, line.y1,
 190                     v0->color[ACOMP], v1->color[ACOMP], line.aPlane);
 191    }
 192    else {
 193       constant_plane(v1->color[RCOMP], line.rPlane);
 194       constant_plane(v1->color[GCOMP], line.gPlane);
 195       constant_plane(v1->color[BCOMP], line.bPlane);
 196       constant_plane(v1->color[ACOMP], line.aPlane);
 197    }
 198 #endif
 199 #ifdef DO_SPEC
 200    if (ctx->Light.ShadeModel == GL_SMOOTH) {
 201       compute_plane(line.x0, line.y0, line.x1, line.y1,
 202                     v0->specular[RCOMP], v1->specular[RCOMP], line.srPlane);
 203       compute_plane(line.x0, line.y0, line.x1, line.y1,
 204                     v0->specular[GCOMP], v1->specular[GCOMP], line.sgPlane);
 205       compute_plane(line.x0, line.y0, line.x1, line.y1,
 206                     v0->specular[BCOMP], v1->specular[BCOMP], line.sbPlane);
 207    }
 208    else {
 209       constant_plane(v1->specular[RCOMP], line.srPlane);
 210       constant_plane(v1->specular[GCOMP], line.sgPlane);
 211       constant_plane(v1->specular[BCOMP], line.sbPlane);
 212    }
 213 #endif
 214 #ifdef DO_INDEX
 215    if (ctx->Light.ShadeModel == GL_SMOOTH) {
 216       compute_plane(line.x0, line.y0, line.x1, line.y1,
 217                     v0->index, v1->index, line.iPlane);
 218    }
 219    else {
 220       constant_plane(v1->index, line.iPlane);
 221    }
 222 #endif
 223 #ifdef DO_TEX
 224    {
 225       const struct gl_texture_object *obj = ctx->Texture.Unit[0]._Current;
 226       const struct gl_texture_image *texImage = obj->Image[obj->BaseLevel];
 227       const GLfloat invW0 = v0->win[3];
 228       const GLfloat invW1 = v1->win[3];
 229       const GLfloat s0 = v0->texcoord[0][0] * invW0;
 230       const GLfloat s1 = v1->texcoord[0][0] * invW1;
 231       const GLfloat t0 = v0->texcoord[0][1] * invW0;
 232       const GLfloat t1 = v1->texcoord[0][1] * invW0;
 233       const GLfloat r0 = v0->texcoord[0][2] * invW0;
 234       const GLfloat r1 = v1->texcoord[0][2] * invW0;
 235       const GLfloat q0 = v0->texcoord[0][3] * invW0;
 236       const GLfloat q1 = v1->texcoord[0][3] * invW0;
 237       compute_plane(line.x0, line.y0, line.x1, line.y1, s0, s1, line.sPlane[0]);
 238       compute_plane(line.x0, line.y0, line.x1, line.y1, t0, t1, line.tPlane[0]);
 239       compute_plane(line.x0, line.y0, line.x1, line.y1, r0, r1, line.uPlane[0]);
 240       compute_plane(line.x0, line.y0, line.x1, line.y1, q0, q1, line.vPlane[0]);
 241       line.texWidth[0] = (GLfloat) texImage->Width;
 242       line.texHeight[0] = (GLfloat) texImage->Height;
 243    }
 244 #elif defined(DO_MULITEX)
 245    {
 246       GLuint u;
 247       for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
 248          if (ctx->Texture.Unit[u].ReallyEnabled) {
 249             const struct gl_texture_object *obj = ctx->Texture.Unit[u].Current;
 250             const struct gl_texture_image *texImage = obj->Image[obj->BaseLevel];
 251             const GLfloat invW0 = v0->win[3];
 252             const GLfloat invW1 = v1->win[3];
 253             GLfloat (*texCoord)[4] = VB->TexCoordPtr[u]->data;
 254             const GLfloat s0 = v0->texcoord[u][0] * invW0;
 255             const GLfloat s1 = v1->texcoord[u][0] * invW1;
 256             const GLfloat t0 = v0->texcoord[u][1] * invW0;
 257             const GLfloat t1 = v1->texcoord[u][1] * invW0;
 258             const GLfloat r0 = v0->texcoord[u][2] * invW0;
 259             const GLfloat r1 = v1->texcoord[u][2] * invW0;
 260             const GLfloat q0 = v0->texcoord[u][3] * invW0;
 261             const GLfloat q1 = v1->texcoord[u][3] * invW0;
 262             compute_plane(line.x0, line.y0, line.x1, line.y1, s0, s1, line.sPlane[u]);
 263             compute_plane(line.x0, line.y0, line.x1, line.y1, t0, t1, line.tPlane[u]);
 264             compute_plane(line.x0, line.y0, line.x1, line.y1, u0, u1, line.uPlane[u]);
 265             compute_plane(line.x0, line.y0, line.x1, line.y1, v0, v1, line.vPlane[u]);
 266             line.texWidth[u]  = (GLfloat) texImage->Width;
 267             line.texHeight[u] = (GLfloat) texImage->Height;
 268          }
 269       }
 270    }
 271 #endif
 272
 273    tStart = tEnd = 0.0;
 274    inSegment = GL_FALSE;
 275    iLen = (GLint) line.len;
 276
 277    if (ctx->Line.StippleFlag) {
 278       for (i = 0; i < iLen; i++) {
 279          const GLuint bit = (swrast->StippleCounter / ctx->Line.StippleFactor) & 0xf;
 280          if ((1 << bit) & ctx->Line.StipplePattern) {
 281             /* stipple bit is on */
 282             const GLfloat t = (GLfloat) i / (GLfloat) line.len;
 283             if (!inSegment) {
 284                /* start new segment */
 285                inSegment = GL_TRUE;
 286                tStart = t;
 287             }
 288             else {
 289                /* still in the segment, extend it */
 290                tEnd = t;
 291             }
 292          }
 293          else {
 294             /* stipple bit is off */
 295             if (inSegment && (tEnd > tStart)) {
 296                /* draw the segment */
 297                segment(ctx, &line, NAME(plot), pb, tStart, tEnd);
 298                inSegment = GL_FALSE;
 299             }
 300             else {
 301                /* still between segments, do nothing */
 302             }
 303          }
 304          swrast->StippleCounter++;
 305       }
 306
 307       if (inSegment) {
 308          /* draw the final segment of the line */
 309          segment(ctx, &line, NAME(plot), pb, tStart, 1.0F);
 310       }
 311    }
 312    else {
 313       /* non-stippled */
 314       segment(ctx, &line, NAME(plot), pb, 0.0, 1.0);
 315    }
 316 }
 317
 318
 319
 320
 321 #undef DO_Z
 322 #undef DO_FOG
 323 #undef DO_RGBA
 324 #undef DO_INDEX
 325 #undef DO_SPEC
 326 #undef DO_TEX
 327 #undef DO_MULTITEX
 328 #undef NAME