reactos/dll/opengl/mesa/swrast/s_aalinetemp.h

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.1
   4  *
   5  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25
  26 /*
  27  * Antialiased line template.
  28  */
  29
  30
  31 /*
  32  * Function to render each fragment in the AA line.
  33  * \param ix  - integer fragment window X coordiante
  34  * \param iy  - integer fragment window Y coordiante
  35  */
  36 static void
  37 NAME(plot)(struct gl_context *ctx, struct LineInfo *line, int ix, int iy)
  38 {
  39    const SWcontext *swrast = SWRAST_CONTEXT(ctx);
  40    const GLfloat fx = (GLfloat) ix;
  41    const GLfloat fy = (GLfloat) iy;
  42    const GLfloat coverage = compute_coveragef(line, ix, iy);
  43    const GLuint i = line->span.end;
  44
  45    (void) swrast;
  46
  47    if (coverage == 0.0)
  48       return;
  49
  50    line->span.end++;
  51    line->span.array->coverage[i] = coverage;
  52    line->span.array->x[i] = ix;
  53    line->span.array->y[i] = iy;
  54
  55    /*
  56     * Compute Z, color, texture coords, fog for the fragment by
  57     * solving the plane equations at (ix,iy).
  58     */
  59 #ifdef DO_Z
  60    line->span.array->z[i] = (GLuint) solve_plane(fx, fy, line->zPlane);
  61 #endif
  62    line->span.array->rgba[i][RCOMP] = solve_plane_chan(fx, fy, line->rPlane);
  63    line->span.array->rgba[i][GCOMP] = solve_plane_chan(fx, fy, line->gPlane);
  64    line->span.array->rgba[i][BCOMP] = solve_plane_chan(fx, fy, line->bPlane);
  65    line->span.array->rgba[i][ACOMP] = solve_plane_chan(fx, fy, line->aPlane);
  66 #if defined(DO_ATTRIBS)
  67    ATTRIB_LOOP_BEGIN
  68       GLfloat (*attribArray)[4] = line->span.array->attribs[attr];
  69       if (attr == FRAG_ATTRIB_TEX) {
  70          /* texcoord w/ divide by Q */
  71          const GLfloat invQ = solve_plane_recip(fx, fy, line->attrPlane[attr][3]);
  72          GLuint c;
  73          for (c = 0; c < 3; c++) {
  74             attribArray[i][c] = solve_plane(fx, fy, line->attrPlane[attr][c]) * invQ;
  75          }
  76          line->span.array->lambda[i]
  77             = compute_lambda(line->attrPlane[attr][0],
  78                              line->attrPlane[attr][1], invQ,
  79                              line->texWidth[attr], line->texHeight[attr]);
  80       }
  81       else {
  82          /* non-texture attrib */
  83          const GLfloat invW = solve_plane_recip(fx, fy, line->wPlane);
  84          GLuint c;
  85          for (c = 0; c < 4; c++) {
  86             attribArray[i][c] = solve_plane(fx, fy, line->attrPlane[attr][c]) * invW;
  87          }
  88       }
  89    ATTRIB_LOOP_END
  90 #endif
  91
  92    if (line->span.end == MAX_WIDTH) {
  93       _swrast_write_rgba_span(ctx, &(line->span));
  94       line->span.end = 0; /* reset counter */
  95    }
  96 }
  97
  98
  99
 100 /*
 101  * Line setup
 102  */
 103 static void
 104 NAME(line)(struct gl_context *ctx, const SWvertex *v0, const SWvertex *v1)
 105 {
 106    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 107    GLfloat tStart, tEnd;   /* segment start, end along line length */
 108    GLboolean inSegment;
 109    GLint iLen, i;
 110
 111    /* Init the LineInfo struct */
 112    struct LineInfo line;
 113    line.x0 = v0->attrib[FRAG_ATTRIB_WPOS][0];
 114    line.y0 = v0->attrib[FRAG_ATTRIB_WPOS][1];
 115    line.x1 = v1->attrib[FRAG_ATTRIB_WPOS][0];
 116    line.y1 = v1->attrib[FRAG_ATTRIB_WPOS][1];
 117    line.dx = line.x1 - line.x0;
 118    line.dy = line.y1 - line.y0;
 119    line.len = SQRTF(line.dx * line.dx + line.dy * line.dy);
 120    line.halfWidth = 0.5F * CLAMP(ctx->Line.Width,
 121                                  ctx->Const.MinLineWidthAA,
 122                                  ctx->Const.MaxLineWidthAA);
 123
 124    if (line.len == 0.0 || IS_INF_OR_NAN(line.len))
 125       return;
 126
 127    INIT_SPAN(line.span, GL_LINE);
 128    line.span.arrayMask = SPAN_XY | SPAN_COVERAGE;
 129    line.span.facing = swrast->PointLineFacing;
 130    line.xAdj = line.dx / line.len * line.halfWidth;
 131    line.yAdj = line.dy / line.len * line.halfWidth;
 132
 133 #ifdef DO_Z
 134    line.span.arrayMask |= SPAN_Z;
 135    compute_plane(line.x0, line.y0, line.x1, line.y1,
 136                  v0->attrib[FRAG_ATTRIB_WPOS][2], v1->attrib[FRAG_ATTRIB_WPOS][2], line.zPlane);
 137 #endif
 138    line.span.arrayMask |= SPAN_RGBA;
 139    if (ctx->Light.ShadeModel == GL_SMOOTH) {
 140       compute_plane(line.x0, line.y0, line.x1, line.y1,
 141                     v0->color[RCOMP], v1->color[RCOMP], line.rPlane);
 142       compute_plane(line.x0, line.y0, line.x1, line.y1,
 143                     v0->color[GCOMP], v1->color[GCOMP], line.gPlane);
 144       compute_plane(line.x0, line.y0, line.x1, line.y1,
 145                     v0->color[BCOMP], v1->color[BCOMP], line.bPlane);
 146       compute_plane(line.x0, line.y0, line.x1, line.y1,
 147                     v0->color[ACOMP], v1->color[ACOMP], line.aPlane);
 148    }
 149    else {
 150       constant_plane(v1->color[RCOMP], line.rPlane);
 151       constant_plane(v1->color[GCOMP], line.gPlane);
 152       constant_plane(v1->color[BCOMP], line.bPlane);
 153       constant_plane(v1->color[ACOMP], line.aPlane);
 154    }
 155 #if defined(DO_ATTRIBS)
 156    {
 157       const GLfloat invW0 = v0->attrib[FRAG_ATTRIB_WPOS][3];
 158       const GLfloat invW1 = v1->attrib[FRAG_ATTRIB_WPOS][3];
 159       line.span.arrayMask |= SPAN_LAMBDA;
 160       compute_plane(line.x0, line.y0, line.x1, line.y1, invW0, invW1, line.wPlane);
 161       ATTRIB_LOOP_BEGIN
 162          GLuint c;
 163          if (swrast->_InterpMode[attr] == GL_FLAT) {
 164             for (c = 0; c < 4; c++) {
 165                constant_plane(v1->attrib[attr][c], line.attrPlane[attr][c]);
 166             }
 167          }
 168          else {
 169             for (c = 0; c < 4; c++) {
 170                const GLfloat a0 = v0->attrib[attr][c] * invW0;
 171                const GLfloat a1 = v1->attrib[attr][c] * invW1;
 172                compute_plane(line.x0, line.y0, line.x1, line.y1, a0, a1,
 173                              line.attrPlane[attr][c]);
 174             }
 175          }
 176          line.span.arrayAttribs |= BITFIELD64_BIT(attr);
 177          if (attr == FRAG_ATTRIB_TEX) {
 178             const struct gl_texture_object *obj = ctx->Texture.Unit._Current;
 179             const struct gl_texture_image *texImage = obj->Image[0][obj->BaseLevel];
 180             line.texWidth[attr]  = (GLfloat) texImage->Width;
 181             line.texHeight[attr] = (GLfloat) texImage->Height;
 182          }
 183       ATTRIB_LOOP_END
 184    }
 185 #endif
 186
 187    tStart = tEnd = 0.0;
 188    inSegment = GL_FALSE;
 189    iLen = (GLint) line.len;
 190
 191    if (ctx->Line.StippleFlag) {
 192       for (i = 0; i < iLen; i++) {
 193          const GLuint bit = (swrast->StippleCounter / ctx->Line.StippleFactor) & 0xf;
 194          if ((1 << bit) & ctx->Line.StipplePattern) {
 195             /* stipple bit is on */
 196             const GLfloat t = (GLfloat) i / (GLfloat) line.len;
 197             if (!inSegment) {
 198                /* start new segment */
 199                inSegment = GL_TRUE;
 200                tStart = t;
 201             }
 202             else {
 203                /* still in the segment, extend it */
 204                tEnd = t;
 205             }
 206          }
 207          else {
 208             /* stipple bit is off */
 209             if (inSegment && (tEnd > tStart)) {
 210                /* draw the segment */
 211                segment(ctx, &line, NAME(plot), tStart, tEnd);
 212                inSegment = GL_FALSE;
 213             }
 214             else {
 215                /* still between segments, do nothing */
 216             }
 217          }
 218          swrast->StippleCounter++;
 219       }
 220
 221       if (inSegment) {
 222          /* draw the final segment of the line */
 223          segment(ctx, &line, NAME(plot), tStart, 1.0F);
 224       }
 225    }
 226    else {
 227       /* non-stippled */
 228       segment(ctx, &line, NAME(plot), 0.0, 1.0);
 229    }
 230
 231    _swrast_write_rgba_span(ctx, &(line.span));
 232 }
 233
 234
 235
 236
 237 #undef DO_Z
 238 #undef DO_ATTRIBS
 239 #undef NAME