From afb833d4e89c312460a4ab9ed6a7a8ca4ebbfe1c Mon Sep 17 00:00:00 2001 From: jtg Date: Thu, 19 Aug 1999 00:55:39 +0000 Subject: Initial revision --- src/mesa/main/fog.c | 327 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 327 insertions(+) create mode 100644 src/mesa/main/fog.c (limited to 'src/mesa/main/fog.c') diff --git a/src/mesa/main/fog.c b/src/mesa/main/fog.c new file mode 100644 index 0000000..1579c8c --- /dev/null +++ b/src/mesa/main/fog.c @@ -0,0 +1,327 @@ +/* $Id: fog.c,v 1.1 1999/08/19 00:55:41 jtg Exp $ */ + +/* + * Mesa 3-D graphics library + * Version: 3.1 + * + * Copyright (C) 1999 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 + * BRIAN PAUL 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. + */ + + +#ifdef PC_HEADER +#include "all.h" +#else +#include +#include +#include "context.h" +#include "fog.h" +#include "macros.h" +#include "mmath.h" +#include "types.h" +#ifdef XFree86Server +#include "GL/xf86glx.h" +#endif +#endif + + + +void gl_Fogfv( GLcontext *ctx, GLenum pname, const GLfloat *params ) +{ + GLenum m; + + switch (pname) { + case GL_FOG_MODE: + m = (GLenum) (GLint) *params; + if (m==GL_LINEAR || m==GL_EXP || m==GL_EXP2) { + ctx->Fog.Mode = m; + } + else { + gl_error( ctx, GL_INVALID_ENUM, "glFog" ); + return; + } + break; + case GL_FOG_DENSITY: + if (*params<0.0) { + gl_error( ctx, GL_INVALID_VALUE, "glFog" ); + return; + } + else { + ctx->Fog.Density = *params; + } + break; + case GL_FOG_START: +#if 0 + /* Prior to OpenGL 1.1, this was an error */ + if (*params<0.0F) { + gl_error( ctx, GL_INVALID_VALUE, "glFog(GL_FOG_START)" ); + return; + } +#endif + ctx->Fog.Start = *params; + break; + case GL_FOG_END: +#if 0 + /* Prior to OpenGL 1.1, this was an error */ + if (*params<0.0F) { + gl_error( ctx, GL_INVALID_VALUE, "glFog(GL_FOG_END)" ); + return; + } +#endif + ctx->Fog.End = *params; + break; + case GL_FOG_INDEX: + ctx->Fog.Index = *params; + break; + case GL_FOG_COLOR: + ctx->Fog.Color[0] = params[0]; + ctx->Fog.Color[1] = params[1]; + ctx->Fog.Color[2] = params[2]; + ctx->Fog.Color[3] = params[3]; + break; + default: + gl_error( ctx, GL_INVALID_ENUM, "glFog" ); + return; + } + + if (ctx->Driver.Fogfv) { + (*ctx->Driver.Fogfv)( ctx, pname, params ); + } + + ctx->NewState |= NEW_FOG; +} + + +typedef void (*fog_func)( struct vertex_buffer *VB, GLuint side, + GLubyte flag ); + + +static fog_func fog_ci_tab[2]; +static fog_func fog_rgba_tab[2]; + +/* + * Compute the fogged color for an array of vertices. + * Input: n - number of vertices + * v - array of vertices + * color - the original vertex colors + * Output: color - the fogged colors + * + */ +#define TAG(x) x##_raw +#define CULLCHECK +#define IDX 0 +#include "fog_tmp.h" + +#define TAG(x) x##_masked +#define CULLCHECK if (cullmask[i]&flag) +#define IDX 1 +#include "fog_tmp.h" + +void gl_init_fog( void ) +{ + init_fog_tab_masked(); + init_fog_tab_raw(); +} + +/* + * Compute fog for the vertices in the vertex buffer. + */ +void gl_fog_vertices( struct vertex_buffer *VB ) +{ + GLcontext *ctx = VB->ctx; + GLuint i = VB->CullMode & 1; + + if (ctx->Visual->RGBAflag) { + /* Fog RGB colors */ + if (ctx->TriangleCaps & DD_TRI_LIGHT_TWOSIDE) { + fog_rgba_tab[i]( VB, 0, VERT_FACE_FRONT ); + fog_rgba_tab[i]( VB, 1, VERT_FACE_REAR ); + } else { + fog_rgba_tab[i]( VB, 0, VERT_FACE_FRONT|VERT_FACE_REAR ); + } + } + else { + /* Fog color indexes */ + if (ctx->TriangleCaps & DD_TRI_LIGHT_TWOSIDE) { + fog_ci_tab[i]( VB, 0, VERT_FACE_FRONT ); + fog_ci_tab[i]( VB, 1, VERT_FACE_REAR ); + } else { + fog_ci_tab[i]( VB, 0, VERT_FACE_FRONT|VERT_FACE_REAR ); + } + } +} + +/* + * Apply fog to an array of RGBA pixels. + * Input: n - number of pixels + * z - array of integer depth values + * red, green, blue, alpha - pixel colors + * Output: red, green, blue, alpha - fogged pixel colors + */ +void gl_fog_rgba_pixels( const GLcontext *ctx, + GLuint n, const GLdepth z[], GLubyte rgba[][4] ) +{ + GLfloat c = ctx->ProjectionMatrix.m[10]; + GLfloat d = ctx->ProjectionMatrix.m[14]; + GLuint i; + + GLfloat rFog = ctx->Fog.Color[0] * 255.0F; + GLfloat gFog = ctx->Fog.Color[1] * 255.0F; + GLfloat bFog = ctx->Fog.Color[2] * 255.0F; + + GLfloat tz = ctx->Viewport.WindowMap.m[MAT_TZ]; + GLfloat szInv = 1.0F / ctx->Viewport.WindowMap.m[MAT_SZ]; + + switch (ctx->Fog.Mode) { + case GL_LINEAR: + { + GLfloat fogEnd = ctx->Fog.End; + GLfloat fogScale = 1.0F / (ctx->Fog.End - ctx->Fog.Start); + for (i=0;iFog.Density * eyez ); + g = 1.0F - f; + rgba[i][RCOMP] = (GLint) (f * rgba[i][RCOMP] + g * rFog); + rgba[i][GCOMP] = (GLint) (f * rgba[i][GCOMP] + g * gFog); + rgba[i][BCOMP] = (GLint) (f * rgba[i][BCOMP] + g * bFog); + } + break; + case GL_EXP2: + { + GLfloat negDensitySquared = -ctx->Fog.Density * ctx->Fog.Density; + for (i=0;iProjectionMatrix.m[10]; + GLfloat d = ctx->ProjectionMatrix.m[14]; + GLuint i; + + GLfloat tz = ctx->Viewport.WindowMap.m[MAT_TZ]; + GLfloat szInv = 1.0F / ctx->Viewport.WindowMap.m[MAT_SZ]; + + switch (ctx->Fog.Mode) { + case GL_LINEAR: + { + GLfloat fogEnd = ctx->Fog.End; + GLfloat fogScale = 1.0F / (ctx->Fog.End - ctx->Fog.Start); + for (i=0;iFog.Index); + } + } + break; + case GL_EXP: + for (i=0;iFog.Density * eyez ); + f = CLAMP( f, 0.0F, 1.0F ); + index[i] = (GLuint) ((GLfloat) index[i] + (1.0F-f) * ctx->Fog.Index); + } + break; + case GL_EXP2: + { + GLfloat negDensitySquared = -ctx->Fog.Density * ctx->Fog.Density; + for (i=0;iFog.Index); + } + } + break; + default: + gl_problem(ctx, "Bad fog mode in gl_fog_ci_pixels"); + return; + } +} + -- cgit v1.1