/*
* Mesa 3-D graphics library
*
* Copyright (C) 1999-2003 Brian Paul All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
#include "glheader.h"
#include "context.h"
#include "fog.h"
#include "macros.h"
#include "mtypes.h"
void GLAPIENTRY
_mesa_Fogf(GLenum pname, GLfloat param)
{
GLfloat fparam[4];
fparam[0] = param;
fparam[1] = fparam[2] = fparam[3] = 0.0F;
_mesa_Fogfv(pname, fparam);
}
void GLAPIENTRY
_mesa_Fogi(GLenum pname, GLint param )
{
GLfloat fparam[4];
fparam[0] = (GLfloat) param;
fparam[1] = fparam[2] = fparam[3] = 0.0F;
_mesa_Fogfv(pname, fparam);
}
void GLAPIENTRY
_mesa_Fogiv(GLenum pname, const GLint *params )
{
GLfloat p[4];
switch (pname) {
case GL_FOG_MODE:
case GL_FOG_DENSITY:
case GL_FOG_START:
case GL_FOG_END:
case GL_FOG_INDEX:
case GL_FOG_COORDINATE_SOURCE_EXT:
p[0] = (GLfloat) *params;
break;
case GL_FOG_COLOR:
p[0] = INT_TO_FLOAT( params[0] );
p[1] = INT_TO_FLOAT( params[1] );
p[2] = INT_TO_FLOAT( params[2] );
p[3] = INT_TO_FLOAT( params[3] );
break;
default:
/* Error will be caught later in _mesa_Fogfv */
ASSIGN_4V(p, 0.0F, 0.0F, 0.0F, 0.0F);
}
_mesa_Fogfv(pname, p);
}
/**
* Update the gl_fog_attrib::_Scale field.
*/
static void
update_fog_scale(struct gl_context *ctx)
{
if (ctx->Fog.End == ctx->Fog.Start)
ctx->Fog._Scale = 1.0f;
else
ctx->Fog._Scale = 1.0f / (ctx->Fog.End - ctx->Fog.Start);
}
void GLAPIENTRY
_mesa_Fogfv( GLenum pname, const GLfloat *params )
{
GET_CURRENT_CONTEXT(ctx);
GLenum m;
switch (pname) {
case GL_FOG_MODE:
m = (GLenum) (GLint) *params;
switch (m) {
case GL_LINEAR:
case GL_EXP:
case GL_EXP2:
break;
default:
_mesa_error( ctx, GL_INVALID_ENUM, "glFog" );
return;
}
if (ctx->Fog.Mode == m)
return;
FLUSH_VERTICES(ctx, _NEW_FOG);
ctx->Fog.Mode = m;
break;
case GL_FOG_DENSITY:
if (*params<0.0) {
_mesa_error( ctx, GL_INVALID_VALUE, "glFog" );
return;
}
if (ctx->Fog.Density == *params)
return;
FLUSH_VERTICES(ctx, _NEW_FOG);
ctx->Fog.Density = *params;
break;
case GL_FOG_START:
if (ctx->Fog.Start == *params)
return;
FLUSH_VERTICES(ctx, _NEW_FOG);
ctx->Fog.Start = *params;
update_fog_scale(ctx);
break;
case GL_FOG_END:
if (ctx->Fog.End == *params)
return;
FLUSH_VERTICES(ctx, _NEW_FOG);
ctx->Fog.End = *params;
update_fog_scale(ctx);
break;
case GL_FOG_INDEX:
if (ctx->API != API_OPENGL_COMPAT)
goto invalid_pname;
if (ctx->Fog.Index == *params)
return;
FLUSH_VERTICES(ctx, _NEW_FOG);
ctx->Fog.Index = *params;
break;
case GL_FOG_COLOR:
if (TEST_EQ_4V(ctx->Fog.Color, params))
return;
FLUSH_VERTICES(ctx, _NEW_FOG);
ctx->Fog.ColorUnclamped[0] = params[0];
ctx->Fog.ColorUnclamped[1] = params[1];
ctx->Fog.ColorUnclamped[2] = params[2];
ctx->Fog.ColorUnclamped[3] = params[3];
ctx->Fog.Color[0] = CLAMP(params[0], 0.0F, 1.0F);
ctx->Fog.Color[1] = CLAMP(params[1], 0.0F, 1.0F);
ctx->Fog.Color[2] = CLAMP(params[2], 0.0F, 1.0F);
ctx->Fog.Color[3] = CLAMP(params[3], 0.0F, 1.0F);
break;
case GL_FOG_COORDINATE_SOURCE_EXT: {
GLenum p = (GLenum) (GLint) *params;
if (ctx->API != API_OPENGL_COMPAT ||
(p != GL_FOG_COORDINATE_EXT && p != GL_FRAGMENT_DEPTH_EXT)) {
_mesa_error(ctx, GL_INVALID_ENUM, "glFog");
return;
}
if (ctx->Fog.FogCoordinateSource == p)
return;
FLUSH_VERTICES(ctx, _NEW_FOG);
ctx->Fog.FogCoordinateSource = p;
break;
}
case GL_FOG_DISTANCE_MODE_NV: {
GLenum p = (GLenum) (GLint) *params;
if (ctx->API != API_OPENGL_COMPAT || !ctx->Extensions.NV_fog_distance ||
(p != GL_EYE_RADIAL_NV && p != GL_EYE_PLANE && p != GL_EYE_PLANE_ABSOLUTE_NV)) {
_mesa_error(ctx, GL_INVALID_ENUM, "glFog");
return;
}
if (ctx->Fog.FogDistanceMode == p)
return;
FLUSH_VERTICES(ctx, _NEW_FOG);
ctx->Fog.FogDistanceMode = p;
break;
}
default:
goto invalid_pname;
}
if (ctx->Driver.Fogfv) {
(*ctx->Driver.Fogfv)( ctx, pname, params );
}
return;
invalid_pname:
_mesa_error( ctx, GL_INVALID_ENUM, "glFog" );
return;
}
/**********************************************************************/
/***** Initialization *****/
/**********************************************************************/
void _mesa_init_fog( struct gl_context * ctx )
{
/* Fog group */
ctx->Fog.Enabled = GL_FALSE;
ctx->Fog.Mode = GL_EXP;
ASSIGN_4V( ctx->Fog.Color, 0.0, 0.0, 0.0, 0.0 );
ASSIGN_4V( ctx->Fog.ColorUnclamped, 0.0, 0.0, 0.0, 0.0 );
ctx->Fog.Index = 0.0;
ctx->Fog.Density = 1.0;
ctx->Fog.Start = 0.0;
ctx->Fog.End = 1.0;
ctx->Fog.ColorSumEnabled = GL_FALSE;
ctx->Fog.FogCoordinateSource = GL_FRAGMENT_DEPTH_EXT;
ctx->Fog._Scale = 1.0f;
ctx->Fog.FogDistanceMode = GL_EYE_PLANE_ABSOLUTE_NV;
}