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.
28 _mesa_Fogf(GLenum pname
, GLfloat param
)
32 fparam
[1] = fparam
[2] = fparam
[3] = 0.0F
;
33 _mesa_Fogfv(pname
, fparam
);
38 _mesa_Fogi(GLenum pname
, GLint param
)
41 fparam
[0] = (GLfloat
) param
;
42 fparam
[1] = fparam
[2] = fparam
[3] = 0.0F
;
43 _mesa_Fogfv(pname
, fparam
);
48 _mesa_Fogiv(GLenum pname
, const GLint
*params
)
57 case GL_FOG_COORDINATE_SOURCE_EXT
:
58 p
[0] = (GLfloat
) *params
;
61 p
[0] = INT_TO_FLOAT( params
[0] );
62 p
[1] = INT_TO_FLOAT( params
[1] );
63 p
[2] = INT_TO_FLOAT( params
[2] );
64 p
[3] = INT_TO_FLOAT( params
[3] );
67 /* Error will be caught later in _mesa_Fogfv */
68 ASSIGN_4V(p
, 0.0F
, 0.0F
, 0.0F
, 0.0F
);
70 _mesa_Fogfv(pname
, p
);
75 * Update the gl_fog_attrib::_Scale field.
78 update_fog_scale(struct gl_context
*ctx
)
80 if (ctx
->Fog
.End
== ctx
->Fog
.Start
)
81 ctx
->Fog
._Scale
= 1.0f
;
83 ctx
->Fog
._Scale
= 1.0f
/ (ctx
->Fog
.End
- ctx
->Fog
.Start
);
88 _mesa_Fogfv( GLenum pname
, const GLfloat
*params
)
90 GET_CURRENT_CONTEXT(ctx
);
92 ASSERT_OUTSIDE_BEGIN_END(ctx
);
96 m
= (GLenum
) (GLint
) *params
;
103 _mesa_error( ctx
, GL_INVALID_ENUM
, "glFog" );
106 if (ctx
->Fog
.Mode
== m
)
108 FLUSH_VERTICES(ctx
, _NEW_FOG
);
113 _mesa_error( ctx
, GL_INVALID_VALUE
, "glFog" );
116 if (ctx
->Fog
.Density
== *params
)
118 FLUSH_VERTICES(ctx
, _NEW_FOG
);
119 ctx
->Fog
.Density
= *params
;
122 if (ctx
->Fog
.Start
== *params
)
124 FLUSH_VERTICES(ctx
, _NEW_FOG
);
125 ctx
->Fog
.Start
= *params
;
126 update_fog_scale(ctx
);
129 if (ctx
->Fog
.End
== *params
)
131 FLUSH_VERTICES(ctx
, _NEW_FOG
);
132 ctx
->Fog
.End
= *params
;
133 update_fog_scale(ctx
);
136 if (ctx
->Fog
.Index
== *params
)
138 FLUSH_VERTICES(ctx
, _NEW_FOG
);
139 ctx
->Fog
.Index
= *params
;
142 if (TEST_EQ_4V(ctx
->Fog
.Color
, params
))
144 FLUSH_VERTICES(ctx
, _NEW_FOG
);
145 ctx
->Fog
.Color
[0] = params
[0];
146 ctx
->Fog
.Color
[1] = params
[1];
147 ctx
->Fog
.Color
[2] = params
[2];
148 ctx
->Fog
.Color
[3] = params
[3];
150 case GL_FOG_COORDINATE_SOURCE_EXT
: {
151 GLenum p
= (GLenum
) (GLint
) *params
;
152 if (!ctx
->Extensions
.EXT_fog_coord
||
153 (p
!= GL_FOG_COORDINATE_EXT
&& p
!= GL_FRAGMENT_DEPTH_EXT
)) {
154 _mesa_error(ctx
, GL_INVALID_ENUM
, "glFog");
157 if (ctx
->Fog
.FogCoordinateSource
== p
)
159 FLUSH_VERTICES(ctx
, _NEW_FOG
);
160 ctx
->Fog
.FogCoordinateSource
= p
;
163 case GL_FOG_DISTANCE_MODE_NV
: {
164 GLenum p
= (GLenum
) (GLint
) *params
;
165 if (!ctx
->Extensions
.NV_fog_distance
||
166 (p
!= GL_EYE_RADIAL_NV
&& p
!= GL_EYE_PLANE
&& p
!= GL_EYE_PLANE_ABSOLUTE_NV
)) {
167 _mesa_error(ctx
, GL_INVALID_ENUM
, "glFog");
170 if (ctx
->Fog
.FogDistanceMode
== p
)
172 FLUSH_VERTICES(ctx
, _NEW_FOG
);
173 ctx
->Fog
.FogDistanceMode
= p
;
177 _mesa_error( ctx
, GL_INVALID_ENUM
, "glFog" );
181 if (ctx
->Driver
.Fogfv
) {
182 (*ctx
->Driver
.Fogfv
)( ctx
, pname
, params
);
187 /**********************************************************************/
188 /***** Initialization *****/
189 /**********************************************************************/
191 void _mesa_init_fog( struct gl_context
* ctx
)
194 ctx
->Fog
.Enabled
= GL_FALSE
;
195 ctx
->Fog
.Mode
= GL_EXP
;
196 ASSIGN_4V( ctx
->Fog
.Color
, 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
.FogCoordinateSource
= GL_FRAGMENT_DEPTH_EXT
;
202 ctx
->Fog
._Scale
= 1.0f
;
203 ctx
->Fog
.FogDistanceMode
= GL_EYE_PLANE_ABSOLUTE_NV
;