src/mesa/swrast/s_pixeltex.c

   1 /* $Id: s_pixeltex.c,v 1.4 2002/01/10 16:54:29 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  4.1
   6  *
   7  * Copyright (C) 1999-2002  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  * This file implements both the GL_SGIX_pixel_texture and
  30  * GL_SIGS_pixel_texture extensions. Luckily, they pretty much
  31  * overlap in functionality so we use the same state variables
  32  * and execution code for both.
  33  */
  34
  35
  36 #include "glheader.h"
  37 #include "colormac.h"
  38
  39 #include "s_context.h"
  40 #include "s_pixeltex.h"
  41
  42
  43 /*
  44  * Convert RGBA values into strq texture coordinates.
  45  */
  46 void
  47 _mesa_pixeltexgen(GLcontext *ctx, GLuint n, const GLchan rgba[][4],
  48                   GLfloat texcoord[][4])
  49 {
  50    if (ctx->Pixel.FragmentRgbSource == GL_CURRENT_RASTER_COLOR) {
  51       GLuint i;
  52       for (i = 0; i < n; i++) {
  53          texcoord[i][0] = ctx->Current.RasterColor[RCOMP];
  54          texcoord[i][1] = ctx->Current.RasterColor[GCOMP];
  55          texcoord[i][2] = ctx->Current.RasterColor[BCOMP];
  56       }
  57    }
  58    else {
  59       GLuint i;
  60       ASSERT(ctx->Pixel.FragmentRgbSource == GL_PIXEL_GROUP_COLOR_SGIS);
  61       for (i = 0; i < n; i++) {
  62          texcoord[i][0] = CHAN_TO_FLOAT(rgba[i][RCOMP]);
  63          texcoord[i][1] = CHAN_TO_FLOAT(rgba[i][GCOMP]);
  64          texcoord[i][2] = CHAN_TO_FLOAT(rgba[i][BCOMP]);
  65       }
  66    }
  67
  68    if (ctx->Pixel.FragmentAlphaSource == GL_CURRENT_RASTER_COLOR) {
  69       GLuint i;
  70       for (i = 0; i < n; i++) {
  71          texcoord[i][3] = ctx->Current.RasterColor[ACOMP];
  72       }
  73    }
  74    else {
  75       GLuint i;
  76       ASSERT(ctx->Pixel.FragmentAlphaSource == GL_PIXEL_GROUP_COLOR_SGIS);
  77       for (i = 0; i < n; i++) {
  78          texcoord[i][3] = CHAN_TO_FLOAT(rgba[i][ACOMP]);
  79       }
  80    }
  81 }