2 * Mesa 3-D graphics library
5 * Copyright (C) 1999-2003 Brian Paul All Rights Reserved.
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:
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
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.
36 _mesa_Fogf(GLenum pname, GLfloat param)
40 fparam[1] = fparam[2] = fparam[3] = 0.0F;
41 _mesa_Fogfv(pname, fparam);
46 _mesa_Fogi(GLenum pname, GLint param )
49 fparam[0] = (GLfloat) param;
50 fparam[1] = fparam[2] = fparam[3] = 0.0F;
51 _mesa_Fogfv(pname, fparam);
56 _mesa_Fogiv(GLenum pname, const GLint *params )
65 case GL_FOG_COORDINATE_SOURCE_EXT:
66 p[0] = (GLfloat) *params;
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] );
75 /* Error will be caught later in _mesa_Fogfv */
76 ASSIGN_4V(p, 0.0F, 0.0F, 0.0F, 0.0F);
78 _mesa_Fogfv(pname, p);
83 * Update the gl_fog_attrib::_Scale field.
86 update_fog_scale(struct gl_context *ctx)
88 if (ctx->Fog.End == ctx->Fog.Start)
89 ctx->Fog._Scale = 1.0f;
91 ctx->Fog._Scale = 1.0f / (ctx->Fog.End - ctx->Fog.Start);
96 _mesa_Fogfv( GLenum pname, const GLfloat *params )
98 GET_CURRENT_CONTEXT(ctx);
100 ASSERT_OUTSIDE_BEGIN_END(ctx);
104 m = (GLenum) (GLint) *params;
111 _mesa_error( ctx, GL_INVALID_ENUM, "glFog" );
114 if (ctx->Fog.Mode == m)
116 FLUSH_VERTICES(ctx, _NEW_FOG);
121 _mesa_error( ctx, GL_INVALID_VALUE, "glFog" );
124 if (ctx->Fog.Density == *params)
126 FLUSH_VERTICES(ctx, _NEW_FOG);
127 ctx->Fog.Density = *params;
130 if (ctx->Fog.Start == *params)
132 FLUSH_VERTICES(ctx, _NEW_FOG);
133 ctx->Fog.Start = *params;
134 update_fog_scale(ctx);
137 if (ctx->Fog.End == *params)
139 FLUSH_VERTICES(ctx, _NEW_FOG);
140 ctx->Fog.End = *params;
141 update_fog_scale(ctx);
144 if (ctx->Fog.Index == *params)
146 FLUSH_VERTICES(ctx, _NEW_FOG);
147 ctx->Fog.Index = *params;
150 if (TEST_EQ_4V(ctx->Fog.Color, params))
152 FLUSH_VERTICES(ctx, _NEW_FOG);
153 ctx->Fog.ColorUnclamped[0] = params[0];
154 ctx->Fog.ColorUnclamped[1] = params[1];
155 ctx->Fog.ColorUnclamped[2] = params[2];
156 ctx->Fog.ColorUnclamped[3] = params[3];
157 ctx->Fog.Color[0] = CLAMP(params[0], 0.0F, 1.0F);
158 ctx->Fog.Color[1] = CLAMP(params[1], 0.0F, 1.0F);
159 ctx->Fog.Color[2] = CLAMP(params[2], 0.0F, 1.0F);
160 ctx->Fog.Color[3] = CLAMP(params[3], 0.0F, 1.0F);
162 case GL_FOG_COORDINATE_SOURCE_EXT: {
163 GLenum p = (GLenum) (GLint) *params;
164 if (!ctx->Extensions.EXT_fog_coord ||
165 (p != GL_FOG_COORDINATE_EXT && p != GL_FRAGMENT_DEPTH_EXT)) {
166 _mesa_error(ctx, GL_INVALID_ENUM, "glFog");
169 if (ctx->Fog.FogCoordinateSource == p)
171 FLUSH_VERTICES(ctx, _NEW_FOG);
172 ctx->Fog.FogCoordinateSource = p;
176 _mesa_error( ctx, GL_INVALID_ENUM, "glFog" );
180 if (ctx->Driver.Fogfv) {
181 (*ctx->Driver.Fogfv)( ctx, pname, params );
186 /**********************************************************************/
187 /***** Initialization *****/
188 /**********************************************************************/
190 void _mesa_init_fog( struct gl_context * ctx )
193 ctx->Fog.Enabled = GL_FALSE;
194 ctx->Fog.Mode = GL_EXP;
195 ASSIGN_4V( ctx->Fog.Color, 0.0, 0.0, 0.0, 0.0 );
196 ASSIGN_4V( ctx->Fog.ColorUnclamped, 0.0, 0.0, 0.0, 0.0 );
197 ctx->Fog.Index = 0.0;
198 ctx->Fog.Density = 1.0;
199 ctx->Fog.Start = 0.0;
201 ctx->Fog.ColorSumEnabled = GL_FALSE;
202 ctx->Fog.FogCoordinateSource = GL_FRAGMENT_DEPTH_EXT;
203 ctx->Fog._Scale = 1.0f;