src/mesa/swrast/s_trispan.h

   1 /* $Id: s_trispan.h,v 1.1 2001/05/14 16:23:04 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 #ifndef S_TRISPAN_H
  29 #define S_TRISPAN_H
  30
  31
  32 /*
  33  * The triangle_span structure is used by the triangle template code in
  34  * s_tritemp.h.  It describes how colors, Z, texcoords, etc are to be
  35  * interpolated across each scanline of triangle.
  36  * With this structure it's easy to hand-off span rasterization to a
  37  * subroutine instead of doing it all inline like we used to do.
  38  * It also cleans up the local variable namespace a great deal.
  39  *
  40  * It would be interesting to experiment with multiprocessor rasterization
  41  * with this structure.  The triangle rasterizer could simply emit a
  42  * stream of these structures which would be consumed by one or more
  43  * span-processing threads which could run in parallel.
  44  */
  45
  46
  47 #define SPAN_RGBA         0x01
  48 #define SPAN_SPEC         0x02
  49 #define SPAN_INDEX        0x04
  50 #define SPAN_Z            0x08
  51 #define SPAN_FOG          0x10
  52 #define SPAN_TEXTURE      0x20
  53 #define SPAN_INT_TEXTURE  0x40
  54 #define SPAN_LAMBDA       0x80
  55
  56
  57 struct triangle_span {
  58    GLint x, y;
  59    GLuint count;
  60    GLuint activeMask;  /* OR of the SPAN_* flags */
  61    GLfixed red, redStep;
  62    GLfixed green, greenStep;
  63    GLfixed blue, blueStep;
  64    GLfixed alpha, alphaStep;
  65    GLfixed specRed, specRedStep;
  66    GLfixed specGreen, specGreenStep;
  67    GLfixed specBlue, specBlueStep;
  68    GLfixed index, indexStep;
  69    GLfixed z, zStep;
  70    GLfloat fog, fogStep;
  71    GLfloat tex[MAX_TEXTURE_UNITS][4], texStep[MAX_TEXTURE_UNITS][4];
  72    GLfixed intTex[2], intTexStep[2];
  73    /* Needed for texture lambda (LOD) computation */
  74    GLfloat rho[MAX_TEXTURE_UNITS];
  75    GLfloat texWidth[MAX_TEXTURE_UNITS], texHeight[MAX_TEXTURE_UNITS];
  76 };
  77
  78
  79 #endif /* S_TRISPAN_H */