X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=src%2Fmesa%2Ftnl%2Ft_vb_fog.c;h=5489ed6857f6b8eff26c2ba1c0dc7fe260007092;hb=08c7474189da25729e4e0bc8755b676e13c2c2c8;hp=d0e87cdbd8a96030fa96d4d17dacb24126073a9a;hpb=363049160da54f4aafe88f99bb2140a9bfed142b;p=mesa.git diff --git a/src/mesa/tnl/t_vb_fog.c b/src/mesa/tnl/t_vb_fog.c index d0e87cdbd8a..5489ed6857f 100644 --- a/src/mesa/tnl/t_vb_fog.c +++ b/src/mesa/tnl/t_vb_fog.c @@ -1,10 +1,7 @@ -/* $Id: t_vb_fog.c,v 1.16 2002/01/06 03:54:12 brianp Exp $ */ - /* * Mesa 3-D graphics library - * Version: 4.1 * - * Copyright (C) 1999-2002 Brian Paul All Rights Reserved. + * Copyright (C) 1999-2006 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"), @@ -19,22 +16,21 @@ * 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. + * 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. * * Authors: - * Keith Whitwell + * Keith Whitwell */ -#include "glheader.h" -#include "colormac.h" -#include "context.h" -#include "macros.h" -#include "mem.h" -#include "mmath.h" -#include "mtypes.h" +#include "c99_math.h" +#include "main/glheader.h" +#include "main/macros.h" +#include "main/imports.h" +#include "main/mtypes.h" #include "math/m_xform.h" @@ -44,14 +40,13 @@ struct fog_stage_data { GLvector4f fogcoord; /* has actual storage allocated */ - GLvector4f input; /* points into VB->EyePtr Z values */ }; #define FOG_STAGE_DATA(stage) ((struct fog_stage_data *)stage->privatePtr) #define FOG_EXP_TABLE_SIZE 256 -#define FOG_MAX (10.0) -#define EXP_FOG_MAX .0006595 +#define FOG_MAX (10.0F) +#define EXP_FOG_MAX .0006595F #define FOG_INCR (FOG_MAX/FOG_EXP_TABLE_SIZE) static GLfloat exp_table[FOG_EXP_TABLE_SIZE]; static GLfloat inited = 0; @@ -59,7 +54,7 @@ static GLfloat inited = 0; #if 1 #define NEG_EXP( result, narg ) \ do { \ - GLfloat f = (GLfloat) (narg * (1.0/FOG_INCR)); \ + GLfloat f = (GLfloat) (narg * (1.0F / FOG_INCR)); \ GLint k = (GLint) f; \ if (k > FOG_EXP_TABLE_SIZE-2) \ result = (GLfloat) EXP_FOG_MAX; \ @@ -74,19 +69,32 @@ do { \ #endif -static void init_static_data( void ) +/** + * Initialize the exp_table[] lookup table for approximating exp(). + */ +static void +init_static_data( void ) { GLfloat f = 0.0F; GLint i = 0; for ( ; i < FOG_EXP_TABLE_SIZE ; i++, f += FOG_INCR) { - exp_table[i] = (GLfloat) exp(-f); + exp_table[i] = expf(-f); } inited = 1; } -static void make_win_fog_coords( GLcontext *ctx, GLvector4f *out, - const GLvector4f *in ) +/** + * Compute per-vertex fog blend factors from fog coordinates by + * evaluating the GL_LINEAR, GL_EXP or GL_EXP2 fog function. + * Fog coordinates are distances from the eye (typically between the + * near and far clip plane distances). + * Note that fogcoords may be negative, if eye z is source absolute + * value must be taken earlier. + * Fog blend factors are in the range [0,1]. + */ +static void +compute_fog_blend_factors(struct gl_context *ctx, GLvector4f *out, const GLvector4f *in) { GLfloat end = ctx->Fog.End; GLfloat *v = in->start; @@ -105,19 +113,22 @@ static void make_win_fog_coords( GLcontext *ctx, GLvector4f *out, else d = 1.0F / (ctx->Fog.End - ctx->Fog.Start); for ( i = 0 ; i < n ; i++, STRIDE_F(v, stride)) { - GLfloat f = (end - ABSF(*v)) * d; + const GLfloat z = *v; + GLfloat f = (end - z) * d; data[i][0] = CLAMP(f, 0.0F, 1.0F); } break; case GL_EXP: d = ctx->Fog.Density; - for ( i = 0 ; i < n ; i++, STRIDE_F(v,stride)) - NEG_EXP( data[i][0], d * ABSF(*v) ); + for ( i = 0 ; i < n ; i++, STRIDE_F(v,stride)) { + const GLfloat z = *v; + NEG_EXP( data[i][0], d * z ); + } break; case GL_EXP2: d = ctx->Fog.Density*ctx->Fog.Density; for ( i = 0 ; i < n ; i++, STRIDE_F(v, stride)) { - GLfloat z = *v; + const GLfloat z = *v; NEG_EXP( data[i][0], d * z * z ); } break; @@ -128,23 +139,28 @@ static void make_win_fog_coords( GLcontext *ctx, GLvector4f *out, } -static GLboolean run_fog_stage( GLcontext *ctx, - struct gl_pipeline_stage *stage ) +static GLboolean +run_fog_stage(struct gl_context *ctx, struct tnl_pipeline_stage *stage) { - struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb; + TNLcontext *tnl = TNL_CONTEXT(ctx); + struct vertex_buffer *VB = &tnl->vb; struct fog_stage_data *store = FOG_STAGE_DATA(stage); GLvector4f *input; - if (stage->changed_inputs == 0) + + if (!ctx->Fog.Enabled) return GL_TRUE; - if (ctx->Fog.FogCoordinateSource == GL_FRAGMENT_DEPTH_EXT) { - /* fog computed from Z depth */ - /* source = VB->ObjPtr or VB->EyePtr coords */ - /* dest = VB->FogCoordPtr = fog stage private storage */ - VB->FogCoordPtr = &store->fogcoord; + if (ctx->Fog.FogCoordinateSource == GL_FRAGMENT_DEPTH_EXT && !ctx->VertexProgram._Current) { + GLuint i; + GLfloat *coord; + /* Fog is computed from vertex or fragment Z values */ + /* source = VB->AttribPtr[_TNL_ATTRIB_POS] or VB->EyePtr coords */ + /* dest = VB->AttribPtr[_TNL_ATTRIB_FOG] = fog stage private storage */ + VB->AttribPtr[_TNL_ATTRIB_FOG] = &store->fogcoord; if (!ctx->_NeedEyeCoords) { + /* compute fog coords from object coords */ const GLfloat *m = ctx->ModelviewMatrixStack.Top->m; GLfloat plane[4]; @@ -156,99 +172,105 @@ static GLboolean run_fog_stage( GLcontext *ctx, plane[1] = m[6]; plane[2] = m[10]; plane[3] = m[14]; - /* Full eye coords weren't required, just calculate the * eye Z values. */ - _mesa_dotprod_tab[VB->ObjPtr->size]( (GLfloat *) input->data, - 4 * sizeof(GLfloat), - VB->ObjPtr, plane ); - - input->count = VB->ObjPtr->count; + _mesa_dotprod_tab[VB->AttribPtr[_TNL_ATTRIB_POS]->size] + ( (GLfloat *) input->data, + 4 * sizeof(GLfloat), + VB->AttribPtr[_TNL_ATTRIB_POS], plane ); + + input->count = VB->AttribPtr[_TNL_ATTRIB_POS]->count; + + /* make sure coords are really positive + NOTE should avoid going through array twice */ + coord = input->start; + for (i = 0; i < input->count; i++) { + *coord = fabsf(*coord); + STRIDE_F(coord, input->stride); + } } else { - input = &store->input; + /* fog coordinates = eye Z coordinates - need to copy for ABS */ + input = &store->fogcoord; if (VB->EyePtr->size < 2) _mesa_vector4f_clean_elem( VB->EyePtr, VB->Count, 2 ); - input->data = (GLfloat (*)[4]) &(VB->EyePtr->data[0][2]); - input->start = VB->EyePtr->start+2; - input->stride = VB->EyePtr->stride; + input->stride = 4 * sizeof(GLfloat); input->count = VB->EyePtr->count; + coord = VB->EyePtr->start; + for (i = 0 ; i < VB->EyePtr->count; i++) { + input->data[i][0] = fabsf(coord[2]); + STRIDE_F(coord, VB->EyePtr->stride); + } } } else { /* use glFogCoord() coordinates */ - /* source = VB->FogCoordPtr */ - input = VB->FogCoordPtr; - /* dest = fog stage private storage */ - VB->FogCoordPtr = &store->fogcoord; - } + input = VB->AttribPtr[_TNL_ATTRIB_FOG]; /* source data */ - make_win_fog_coords( ctx, VB->FogCoordPtr, input ); - return GL_TRUE; -} + /* input->count may be one if glFogCoord was only called once + * before glBegin. But we need to compute fog for all vertices. + */ + input->count = VB->AttribPtr[_TNL_ATTRIB_POS]->count; + VB->AttribPtr[_TNL_ATTRIB_FOG] = &store->fogcoord; /* dest data */ + } -static void check_fog_stage( GLcontext *ctx, struct gl_pipeline_stage *stage ) -{ - stage->active = ctx->Fog.Enabled && !ctx->VertexProgram.Enabled; + if (tnl->_DoVertexFog) { + /* compute blend factors from fog coordinates */ + compute_fog_blend_factors( ctx, VB->AttribPtr[_TNL_ATTRIB_FOG], input ); + } + else { + /* results = incoming fog coords (compute fog per-fragment later) */ + VB->AttribPtr[_TNL_ATTRIB_FOG] = input; + } - if (ctx->Fog.FogCoordinateSource == GL_FRAGMENT_DEPTH_EXT) - stage->inputs = VERT_EYE; - else - stage->inputs = VERT_FOG_BIT; + return GL_TRUE; } + /* Called the first time stage->run() is invoked. */ -static GLboolean alloc_fog_data( GLcontext *ctx, - struct gl_pipeline_stage *stage ) +static GLboolean +alloc_fog_data(struct gl_context *ctx, struct tnl_pipeline_stage *stage) { TNLcontext *tnl = TNL_CONTEXT(ctx); struct fog_stage_data *store; - stage->privatePtr = MALLOC(sizeof(*store)); + stage->privatePtr = malloc(sizeof(*store)); store = FOG_STAGE_DATA(stage); if (!store) return GL_FALSE; _mesa_vector4f_alloc( &store->fogcoord, 0, tnl->vb.Size, 32 ); - _mesa_vector4f_init( &store->input, 0, 0 ); if (!inited) init_static_data(); - /* Now run the stage. - */ - stage->run = run_fog_stage; - return stage->run( ctx, stage ); + return GL_TRUE; } -static void free_fog_data( struct gl_pipeline_stage *stage ) +static void +free_fog_data(struct tnl_pipeline_stage *stage) { struct fog_stage_data *store = FOG_STAGE_DATA(stage); if (store) { _mesa_vector4f_free( &store->fogcoord ); - FREE( store ); + free( store ); stage->privatePtr = NULL; } } -const struct gl_pipeline_stage _tnl_fog_coordinate_stage = +const struct tnl_pipeline_stage _tnl_fog_coordinate_stage = { "build fog coordinates", /* name */ - _NEW_FOG, /* check_state */ - _NEW_FOG, /* run_state */ - GL_FALSE, /* active? */ - 0, /* inputs */ - VERT_FOG_BIT, /* outputs */ - 0, /* changed_inputs */ NULL, /* private_data */ + alloc_fog_data, /* dtr */ free_fog_data, /* dtr */ - check_fog_stage, /* check */ - alloc_fog_data /* run -- initially set to init. */ + NULL, /* check */ + run_fog_stage /* run -- initially set to init. */ };