t_vb_normals.c revision a328e469d328f8b6fd5afdfc21d576fa1a2c43fc
1/* 2 * Mesa 3-D graphics library 3 * Version: 6.5 4 * 5 * Copyright (C) 1999-2006 Brian Paul All Rights Reserved. 6 * 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: 13 * 14 * The above copyright notice and this permission notice shall be included 15 * in all copies or substantial portions of the Software. 16 * 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. 23 * 24 * Authors: 25 * Keith Whitwell <keith@tungstengraphics.com> 26 */ 27 28 29#include "glheader.h" 30#include "colormac.h" 31#include "context.h" 32#include "macros.h" 33#include "imports.h" 34#include "mtypes.h" 35 36#include "math/m_xform.h" 37 38#include "t_context.h" 39#include "t_pipeline.h" 40 41 42struct normal_stage_data { 43 normal_func NormalTransform; 44 GLvector4f normal; 45}; 46 47#define NORMAL_STAGE_DATA(stage) ((struct normal_stage_data *)stage->privatePtr) 48 49 50static GLboolean 51run_normal_stage(GLcontext *ctx, struct tnl_pipeline_stage *stage) 52{ 53 struct normal_stage_data *store = NORMAL_STAGE_DATA(stage); 54 struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb; 55 const GLfloat *lengths; 56 57 if (!store->NormalTransform) 58 return GL_TRUE; 59 60 /* We can only use the display list's saved normal lengths if we've 61 * got a transformation matrix with uniform scaling. 62 */ 63 if (_math_matrix_is_general_scale(ctx->ModelviewMatrixStack.Top)) 64 lengths = NULL; 65 else 66 lengths = VB->NormalLengthPtr; 67 68 store->NormalTransform( ctx->ModelviewMatrixStack.Top, 69 ctx->_ModelViewInvScale, 70 VB->AttribPtr[_TNL_ATTRIB_NORMAL], /* input normals */ 71 lengths, 72 &store->normal ); /* resulting normals */ 73 74 if (VB->AttribPtr[_TNL_ATTRIB_NORMAL]->count > 1) { 75 store->normal.stride = 4 * sizeof(GLfloat); 76 } 77 else { 78 store->normal.stride = 0; 79 } 80 81 VB->AttribPtr[_TNL_ATTRIB_NORMAL] = &store->normal; 82 VB->NormalPtr = &store->normal; 83 84 VB->NormalLengthPtr = NULL; /* no longer valid */ 85 return GL_TRUE; 86} 87 88 89/** 90 * Examine current GL state and set the store->NormalTransform pointer 91 * to point to the appropriate normal transformation routine. 92 */ 93static void 94validate_normal_stage(GLcontext *ctx, struct tnl_pipeline_stage *stage) 95{ 96 struct normal_stage_data *store = NORMAL_STAGE_DATA(stage); 97 98 if (ctx->VertexProgram._Current || 99 (!ctx->Light.Enabled && 100 !(ctx->Texture._GenFlags & TEXGEN_NEED_NORMALS))) { 101 store->NormalTransform = NULL; 102 return; 103 } 104 105 if (ctx->_NeedEyeCoords) { 106 /* Eye coordinates are needed, for whatever reasons. 107 * Do lighting in eye coordinates, as the GL spec says. 108 */ 109 GLuint transform = NORM_TRANSFORM_NO_ROT; 110 111 if (_math_matrix_has_rotation(ctx->ModelviewMatrixStack.Top)) { 112 /* need to do full (3x3) matrix transform */ 113 transform = NORM_TRANSFORM; 114 } 115 116 if (ctx->Transform.Normalize) { 117 store->NormalTransform = _mesa_normal_tab[transform | NORM_NORMALIZE]; 118 } 119 else if (ctx->Transform.RescaleNormals && 120 ctx->_ModelViewInvScale != 1.0) { 121 store->NormalTransform = _mesa_normal_tab[transform | NORM_RESCALE]; 122 } 123 else { 124 store->NormalTransform = _mesa_normal_tab[transform]; 125 } 126 } 127 else { 128 /* We don't need eye coordinates. 129 * Do lighting in object coordinates. Thus, we don't need to fully 130 * transform normal vectors (just leave them in object coordinates) 131 * but we still need to do normalization/rescaling if enabled. 132 */ 133 if (ctx->Transform.Normalize) { 134 store->NormalTransform = _mesa_normal_tab[NORM_NORMALIZE]; 135 } 136 else if (!ctx->Transform.RescaleNormals && 137 ctx->_ModelViewInvScale != 1.0) { 138 store->NormalTransform = _mesa_normal_tab[NORM_RESCALE]; 139 } 140 else { 141 store->NormalTransform = NULL; 142 } 143 } 144} 145 146 147/** 148 * Allocate stage's private data (storage for transformed normals). 149 */ 150static GLboolean 151alloc_normal_data(GLcontext *ctx, struct tnl_pipeline_stage *stage) 152{ 153 TNLcontext *tnl = TNL_CONTEXT(ctx); 154 struct normal_stage_data *store; 155 156 stage->privatePtr = _mesa_malloc(sizeof(*store)); 157 store = NORMAL_STAGE_DATA(stage); 158 if (!store) 159 return GL_FALSE; 160 161 _mesa_vector4f_alloc( &store->normal, 0, tnl->vb.Size, 32 ); 162 return GL_TRUE; 163} 164 165 166/** 167 * Free stage's private data. 168 */ 169static void 170free_normal_data(struct tnl_pipeline_stage *stage) 171{ 172 struct normal_stage_data *store = NORMAL_STAGE_DATA(stage); 173 if (store) { 174 _mesa_vector4f_free( &store->normal ); 175 _mesa_free( store ); 176 stage->privatePtr = NULL; 177 } 178} 179 180 181const struct tnl_pipeline_stage _tnl_normal_transform_stage = 182{ 183 "normal transform", /* name */ 184 NULL, /* privatePtr */ 185 alloc_normal_data, /* create */ 186 free_normal_data, /* destroy */ 187 validate_normal_stage, /* validate */ 188 run_normal_stage /* run */ 189}; 190