src/mesa/main/fog.c

   1 /* $Id: fog.c,v 1.29 2000/11/16 21:05:35 keithw Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.5
   6  *
   7  * Copyright (C) 1999-2000  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 #ifdef PC_HEADER
  29 #include "all.h"
  30 #else
  31 #include "glheader.h"
  32 #include "colormac.h"
  33 #include "context.h"
  34 #include "fog.h"
  35 #include "types.h"
  36 #endif
  37
  38
  39
  40 void
  41 _mesa_Fogf(GLenum pname, GLfloat param)
  42 {
  43    _mesa_Fogfv(pname, &param);
  44 }
  45
  46
  47 void
  48 _mesa_Fogi(GLenum pname, GLint param )
  49 {
  50    GLfloat fparam = (GLfloat) param;
  51    _mesa_Fogfv(pname, &fparam);
  52 }
  53
  54
  55 void
  56 _mesa_Fogiv(GLenum pname, const GLint *params )
  57 {
  58    GLfloat p[4];
  59    switch (pname) {
  60       case GL_FOG_MODE:
  61       case GL_FOG_DENSITY:
  62       case GL_FOG_START:
  63       case GL_FOG_END:
  64       case GL_FOG_INDEX:
  65       case GL_FOG_COORDINATE_SOURCE_EXT:
  66          p[0] = (GLfloat) *params;
  67          break;
  68       case GL_FOG_COLOR:
  69          p[0] = INT_TO_FLOAT( params[0] );
  70          p[1] = INT_TO_FLOAT( params[1] );
  71          p[2] = INT_TO_FLOAT( params[2] );
  72          p[3] = INT_TO_FLOAT( params[3] );
  73          break;
  74       default:
  75          /* Error will be caught later in _mesa_Fogfv */
  76          ;
  77    }
  78    _mesa_Fogfv(pname, p);
  79 }
  80
  81
  82 void
  83 _mesa_Fogfv( GLenum pname, const GLfloat *params )
  84 {
  85    GET_CURRENT_CONTEXT(ctx);
  86    GLenum m;
  87
  88    ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx, "glFog");
  89
  90    switch (pname) {
  91       case GL_FOG_MODE:
  92          m = (GLenum) (GLint) *params;
  93          if (m==GL_LINEAR || m==GL_EXP || m==GL_EXP2) {
  94             ctx->Fog.Mode = m;
  95          }
  96          else {
  97             gl_error( ctx, GL_INVALID_ENUM, "glFog" );
  98             return;
  99          }
 100          break;
 101       case GL_FOG_DENSITY:
 102          if (*params<0.0) {
 103             gl_error( ctx, GL_INVALID_VALUE, "glFog" );
 104             return;
 105          }
 106          else {
 107             ctx->Fog.Density = *params;
 108          }
 109          break;
 110       case GL_FOG_START:
 111          ctx->Fog.Start = *params;
 112          break;
 113       case GL_FOG_END:
 114          ctx->Fog.End = *params;
 115          break;
 116       case GL_FOG_INDEX:
 117          ctx->Fog.Index = *params;
 118          break;
 119       case GL_FOG_COLOR:
 120          ctx->Fog.Color[0] = params[0];
 121          ctx->Fog.Color[1] = params[1];
 122          ctx->Fog.Color[2] = params[2];
 123          ctx->Fog.Color[3] = params[3];
 124          break;
 125       case GL_FOG_COORDINATE_SOURCE_EXT: {
 126          GLenum p = (GLenum)(GLint) *params;
 127          if (p == GL_FOG_COORDINATE_EXT || p == GL_FRAGMENT_DEPTH_EXT)
 128             ctx->Fog.FogCoordinateSource = p;
 129          else
 130             gl_error( ctx, GL_INVALID_ENUM, "glFog" );
 131          break;
 132       }
 133       default:
 134          gl_error( ctx, GL_INVALID_ENUM, "glFog" );
 135          return;
 136    }
 137
 138    if (ctx->Driver.Fogfv) {
 139       (*ctx->Driver.Fogfv)( ctx, pname, params );
 140    }
 141
 142    ctx->NewState |= _NEW_FOG;
 143 }
 144
 145