2 * Mesa 3-D graphics library
4 * Copyright (C) 1999-2003 Brian Paul All Rights Reserved.
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
35 _mesa_Fogf(GLenum pname
, GLfloat param
)
39 fparam
[1] = fparam
[2] = fparam
[3] = 0.0F
;
40 _mesa_Fogfv(pname
, fparam
);
45 _mesa_Fogi(GLenum pname
, GLint param
)
48 fparam
[0] = (GLfloat
) param
;
49 fparam
[1] = fparam
[2] = fparam
[3] = 0.0F
;
50 _mesa_Fogfv(pname
, fparam
);
55 _mesa_Fogiv(GLenum pname
, const GLint
*params
)
64 case GL_FOG_COORDINATE_SOURCE_EXT
:
65 p
[0] = (GLfloat
) *params
;
68 p
[0] = INT_TO_FLOAT( params
[0] );
69 p
[1] = INT_TO_FLOAT( params
[1] );
70 p
[2] = INT_TO_FLOAT( params
[2] );
71 p
[3] = INT_TO_FLOAT( params
[3] );
74 /* Error will be caught later in _mesa_Fogfv */
75 ASSIGN_4V(p
, 0.0F
, 0.0F
, 0.0F
, 0.0F
);
77 _mesa_Fogfv(pname
, p
);
82 * Update the gl_fog_attrib::_Scale field.
85 update_fog_scale(struct gl_context
*ctx
)
87 if (ctx
->Fog
.End
== ctx
->Fog
.Start
)
88 ctx
->Fog
._Scale
= 1.0f
;
90 ctx
->Fog
._Scale
= 1.0f
/ (ctx
->Fog
.End
- ctx
->Fog
.Start
);
95 _mesa_Fogfv( GLenum pname
, const GLfloat
*params
)
97 GET_CURRENT_CONTEXT(ctx
);
102 m
= (GLenum
) (GLint
) *params
;
109 _mesa_error( ctx
, GL_INVALID_ENUM
, "glFog" );
112 if (ctx
->Fog
.Mode
== m
)
114 FLUSH_VERTICES(ctx
, _NEW_FOG
);
119 _mesa_error( ctx
, GL_INVALID_VALUE
, "glFog" );
122 if (ctx
->Fog
.Density
== *params
)
124 FLUSH_VERTICES(ctx
, _NEW_FOG
);
125 ctx
->Fog
.Density
= *params
;
128 if (ctx
->Fog
.Start
== *params
)
130 FLUSH_VERTICES(ctx
, _NEW_FOG
);
131 ctx
->Fog
.Start
= *params
;
132 update_fog_scale(ctx
);
135 if (ctx
->Fog
.End
== *params
)
137 FLUSH_VERTICES(ctx
, _NEW_FOG
);
138 ctx
->Fog
.End
= *params
;
139 update_fog_scale(ctx
);
142 if (ctx
->API
!= API_OPENGL_COMPAT
)
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
->API
!= API_OPENGL_COMPAT
||
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
;
175 case GL_FOG_DISTANCE_MODE_NV
: {
176 GLenum p
= (GLenum
) (GLint
) *params
;
177 if (ctx
->API
!= API_OPENGL_COMPAT
|| !ctx
->Extensions
.NV_fog_distance
||
178 (p
!= GL_EYE_RADIAL_NV
&& p
!= GL_EYE_PLANE
&& p
!= GL_EYE_PLANE_ABSOLUTE_NV
)) {
179 _mesa_error(ctx
, GL_INVALID_ENUM
, "glFog");
182 if (ctx
->Fog
.FogDistanceMode
== p
)
184 FLUSH_VERTICES(ctx
, _NEW_FOG
);
185 ctx
->Fog
.FogDistanceMode
= p
;
192 if (ctx
->Driver
.Fogfv
) {
193 ctx
->Driver
.Fogfv( ctx
, pname
, params
);
199 _mesa_error( ctx
, GL_INVALID_ENUM
, "glFog" );
204 /**********************************************************************/
205 /***** Initialization *****/
206 /**********************************************************************/
208 void _mesa_init_fog( struct gl_context
* ctx
)
211 ctx
->Fog
.Enabled
= GL_FALSE
;
212 ctx
->Fog
.Mode
= GL_EXP
;
213 ASSIGN_4V( ctx
->Fog
.Color
, 0.0, 0.0, 0.0, 0.0 );
214 ASSIGN_4V( ctx
->Fog
.ColorUnclamped
, 0.0, 0.0, 0.0, 0.0 );
215 ctx
->Fog
.Index
= 0.0;
216 ctx
->Fog
.Density
= 1.0;
217 ctx
->Fog
.Start
= 0.0;
219 ctx
->Fog
.ColorSumEnabled
= GL_FALSE
;
220 ctx
->Fog
.FogCoordinateSource
= GL_FRAGMENT_DEPTH_EXT
;
221 ctx
->Fog
._Scale
= 1.0f
;
222 ctx
->Fog
.FogDistanceMode
= GL_EYE_PLANE_ABSOLUTE_NV
;