reactos/dll/opengl/mesa/tnl/t_vb_normals.c

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/*
* Mesa 3-D graphics library
* Version: 6.5
*
* 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"),
* 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.
*
* Authors:
* Keith Whitwell <keith@tungstengraphics.com>
*/
#include <precomp.h>
struct normal_stage_data {
normal_func NormalTransform;
GLvector4f normal;
};
#define NORMAL_STAGE_DATA(stage) ((struct normal_stage_data *)stage->privatePtr)
static GLboolean
run_normal_stage(struct gl_context *ctx, struct tnl_pipeline_stage *stage)
{
struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
const GLfloat *lengths;
if (!store->NormalTransform)
return GL_TRUE;
/* We can only use the display list's saved normal lengths if we've
* got a transformation matrix with uniform scaling.
*/
if (_math_matrix_is_general_scale(ctx->ModelviewMatrixStack.Top))
lengths = NULL;
else
lengths = VB->NormalLengthPtr;
store->NormalTransform( ctx->ModelviewMatrixStack.Top,
ctx->_ModelViewInvScale,
VB->AttribPtr[_TNL_ATTRIB_NORMAL], /* input normals */
lengths,
&store->normal ); /* resulting normals */
if (VB->AttribPtr[_TNL_ATTRIB_NORMAL]->count > 1) {
store->normal.stride = 4 * sizeof(GLfloat);
}
else {
store->normal.stride = 0;
}
VB->AttribPtr[_TNL_ATTRIB_NORMAL] = &store->normal;
VB->NormalLengthPtr = NULL; /* no longer valid */
return GL_TRUE;
}
/**
* Examine current GL state and set the store->NormalTransform pointer
* to point to the appropriate normal transformation routine.
*/
static void
validate_normal_stage(struct gl_context *ctx, struct tnl_pipeline_stage *stage)
{
struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
if (!ctx->Light.Enabled &&
!(ctx->Texture._GenFlags & TEXGEN_NEED_NORMALS)) {
store->NormalTransform = NULL;
return;
}
if (ctx->_NeedEyeCoords) {
/* Eye coordinates are needed, for whatever reasons.
* Do lighting in eye coordinates, as the GL spec says.
*/
GLuint transform = NORM_TRANSFORM_NO_ROT;
if (_math_matrix_has_rotation(ctx->ModelviewMatrixStack.Top)) {
/* need to do full (3x3) matrix transform */
transform = NORM_TRANSFORM;
}
if (ctx->Transform.Normalize) {
store->NormalTransform = _mesa_normal_tab[transform | NORM_NORMALIZE];
}
else if (ctx->Transform.RescaleNormals &&
ctx->_ModelViewInvScale != 1.0) {
store->NormalTransform = _mesa_normal_tab[transform | NORM_RESCALE];
}
else {
store->NormalTransform = _mesa_normal_tab[transform];
}
}
else {
/* We don't need eye coordinates.
* Do lighting in object coordinates. Thus, we don't need to fully
* transform normal vectors (just leave them in object coordinates)
* but we still need to do normalization/rescaling if enabled.
*/
if (ctx->Transform.Normalize) {
store->NormalTransform = _mesa_normal_tab[NORM_NORMALIZE];
}
else if (!ctx->Transform.RescaleNormals &&
ctx->_ModelViewInvScale != 1.0) {
store->NormalTransform = _mesa_normal_tab[NORM_RESCALE];
}
else {
store->NormalTransform = NULL;
}
}
}
/**
* Allocate stage's private data (storage for transformed normals).
*/
static GLboolean
alloc_normal_data(struct gl_context *ctx, struct tnl_pipeline_stage *stage)
{
TNLcontext *tnl = TNL_CONTEXT(ctx);
struct normal_stage_data *store;
stage->privatePtr = malloc(sizeof(*store));
store = NORMAL_STAGE_DATA(stage);
if (!store)
return GL_FALSE;
_mesa_vector4f_alloc( &store->normal, 0, tnl->vb.Size, 32 );
return GL_TRUE;
}
/**
* Free stage's private data.
*/
static void
free_normal_data(struct tnl_pipeline_stage *stage)
{
struct normal_stage_data *store = NORMAL_STAGE_DATA(stage);
if (store) {
_mesa_vector4f_free( &store->normal );
free( store );
stage->privatePtr = NULL;
}
}
const struct tnl_pipeline_stage _tnl_normal_transform_stage =
{
"normal transform", /* name */
NULL, /* privatePtr */
alloc_normal_data, /* create */
free_normal_data, /* destroy */
validate_normal_stage, /* validate */
run_normal_stage /* run */
};