/*
* Mesa 3-D graphics library
*
* 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
* 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 "c99_math.h"
#include "main/glheader.h"
#include "main/light.h"
#include "main/macros.h"
#include "main/imports.h"
#include "util/simple_list.h"
#include "main/mtypes.h"
#include "math/m_translate.h"
#include "t_context.h"
#include "t_pipeline.h"
#include "tnl.h"
#define LIGHT_TWOSIDE 0x1
#define LIGHT_MATERIAL 0x2
#define MAX_LIGHT_FUNC 0x4
typedef void (*light_func)( struct gl_context *ctx,
struct vertex_buffer *VB,
struct tnl_pipeline_stage *stage,
GLvector4f *input );
/**
* Information for updating current material attributes from vertex color,
* for GL_COLOR_MATERIAL.
*/
struct material_cursor {
const GLfloat *ptr; /* points to src vertex color (in VB array) */
GLuint stride; /* stride to next vertex color (bytes) */
GLfloat *current; /* points to material attribute to update */
GLuint size; /* vertex/color size: 1, 2, 3 or 4 */
};
/**
* Data private to this pipeline stage.
*/
struct light_stage_data {
GLvector4f Input;
GLvector4f LitColor[2];
GLvector4f LitSecondary[2];
light_func *light_func_tab;
struct material_cursor mat[MAT_ATTRIB_MAX];
GLuint mat_count;
GLuint mat_bitmask;
};
#define LIGHT_STAGE_DATA(stage) ((struct light_stage_data *)(stage->privatePtr))
/**********************************************************************/
/***** Lighting computation *****/
/**********************************************************************/
/*
* Notes:
* When two-sided lighting is enabled we compute the color (or index)
* for both the front and back side of the primitive. Then, when the
* orientation of the facet is later learned, we can determine which
* color (or index) to use for rendering.
*
* KW: We now know orientation in advance and only shade for
* the side or sides which are actually required.
*
* Variables:
* n = normal vector
* V = vertex position
* P = light source position
* Pe = (0,0,0,1)
*
* Precomputed:
* IF P[3]==0 THEN
* // light at infinity
* IF local_viewer THEN
* _VP_inf_norm = unit vector from V to P // Precompute
* ELSE
* // eye at infinity
* _h_inf_norm = Normalize( VP + <0,0,1> ) // Precompute
* ENDIF
* ENDIF
*
* Functions:
* Normalize( v ) = normalized vector v
* Magnitude( v ) = length of vector v
*/
static void
validate_shine_table( struct gl_context *ctx, GLuint side, GLfloat shininess )
{
TNLcontext *tnl = TNL_CONTEXT(ctx);
struct tnl_shine_tab *list = tnl->_ShineTabList;
struct tnl_shine_tab *s;
foreach(s, list)
if ( s->shininess == shininess )
break;
if (s == list) {
GLint j;
GLfloat *m;
foreach(s, list)
if (s->refcount == 0)
break;
m = s->tab;
m[0] = 0.0;
if (shininess == 0.0) {
for (j = 1 ; j <= SHINE_TABLE_SIZE ; j++)
m[j] = 1.0;
}
else {
for (j = 1 ; j < SHINE_TABLE_SIZE ; j++) {
GLdouble t, x = j / (GLfloat) (SHINE_TABLE_SIZE - 1);
if (x < 0.005) /* underflow check */
x = 0.005;
if (t > 1e-20)
m[j] = (GLfloat) t;
else
m[j] = 0.0;
}
m[SHINE_TABLE_SIZE] = 1.0;
}
s->shininess = shininess;
}
if (tnl->_ShineTable[side])
tnl->_ShineTable[side]->refcount--;
tnl->_ShineTable[side] = s;
move_to_tail( list, s );
s->refcount++;
}
void
_tnl_validate_shine_tables( struct gl_context *ctx )
{
TNLcontext *tnl = TNL_CONTEXT(ctx);
GLfloat shininess;
shininess = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_SHININESS][0];
if (!tnl->_ShineTable[0] || tnl->_ShineTable[0]->shininess != shininess)
validate_shine_table( ctx, 0, shininess );
shininess = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_SHININESS][0];
if (!tnl->_ShineTable[1] || tnl->_ShineTable[1]->shininess != shininess)
validate_shine_table( ctx, 1, shininess );
}
/**
* In the case of colormaterial, the effected material attributes
* should already have been bound to point to the incoming color data,
* prior to running the pipeline.
* This function copies the vertex's color to the material attributes
* which are tracking glColor.
* It's called per-vertex in the lighting loop.
*/
static void
update_materials(struct gl_context *ctx, struct light_stage_data *store)
{
GLuint i;
for (i = 0 ; i < store->mat_count ; i++) {
/* update the material */
COPY_CLEAN_4V(store->mat[i].current, store->mat[i].size, store->mat[i].ptr);
/* increment src vertex color pointer */
STRIDE_F(store->mat[i].ptr, store->mat[i].stride);
}
/* recompute derived light/material values */
_mesa_update_material( ctx, store->mat_bitmask );
/* XXX we should only call this if we're tracking/changing the specular
* exponent.
*/
_tnl_validate_shine_tables( ctx );
}
/**
* Prepare things prior to running the lighting stage.
* Return number of material attributes which will track vertex color.
*/
static GLuint
prepare_materials(struct gl_context *ctx,
struct vertex_buffer *VB, struct light_stage_data *store)
{
GLuint i;
store->mat_count = 0;
store->mat_bitmask = 0;
/* Examine the _ColorMaterialBitmask to determine which materials
* track vertex color. Override the material attribute's pointer
* with the color pointer for each one.
*/
if (ctx->Light.ColorMaterialEnabled) {
const GLuint bitmask = ctx->Light._ColorMaterialBitmask;
for (i = 0 ; i < MAT_ATTRIB_MAX ; i++)
if (bitmask & (1<<i))
VB->AttribPtr[_TNL_ATTRIB_MAT_FRONT_AMBIENT + i] = VB->AttribPtr[_TNL_ATTRIB_COLOR0];
}
/* Now, for each material attribute that's tracking vertex color, save
* some values (ptr, stride, size, current) that we'll need in
* update_materials(), above, that'll actually copy the vertex color to
* the material attribute(s).
*/
for (i = _TNL_FIRST_MAT; i <= _TNL_LAST_MAT; i++) {
if (VB->AttribPtr[i]->stride) {
const GLuint j = store->mat_count++;
const GLuint attr = i - _TNL_ATTRIB_MAT_FRONT_AMBIENT;
store->mat[j].ptr = VB->AttribPtr[i]->start;
store->mat[j].stride = VB->AttribPtr[i]->stride;
store->mat[j].size = VB->AttribPtr[i]->size;
store->mat[j].current = ctx->Light.Material.Attrib[attr];
store->mat_bitmask |= (1<<attr);
}
}
/* FIXME: Is this already done?
*/
_mesa_update_material( ctx, ~0 );
_tnl_validate_shine_tables( ctx );
return store->mat_count;
}
/*
* Compute dp ^ SpecularExponent.
* Lerp between adjacent values in the f(x) lookup table, giving a
* continuous function, with adequate overall accuracy. (Though still
* pretty good compared to a straight lookup).
*/
static inline GLfloat
lookup_shininess(const struct gl_context *ctx, GLuint face, GLfloat dp)
{
TNLcontext *tnl = TNL_CONTEXT(ctx);
const struct tnl_shine_tab *tab = tnl->_ShineTable[face];
float f = dp * (SHINE_TABLE_SIZE - 1);
int k = (int) f;
if (k < 0 /* gcc may cast an overflow float value to negative int value */
|| k > SHINE_TABLE_SIZE - 2)
return powf(dp, tab->shininess);
else
return tab->tab[k] + (f - k) * (tab->tab[k+1] - tab->tab[k]);
}
/* Tables for all the shading functions.
*/
static light_func _tnl_light_tab[MAX_LIGHT_FUNC];
static light_func _tnl_light_fast_tab[MAX_LIGHT_FUNC];
static light_func _tnl_light_fast_single_tab[MAX_LIGHT_FUNC];
static light_func _tnl_light_spec_tab[MAX_LIGHT_FUNC];
#define TAG(x) x
#define IDX (0)
#include "t_vb_lighttmp.h"
#define TAG(x) x##_twoside
#define IDX (LIGHT_TWOSIDE)
#include "t_vb_lighttmp.h"
#define TAG(x) x##_material
#define IDX (LIGHT_MATERIAL)
#include "t_vb_lighttmp.h"
#define TAG(x) x##_twoside_material
#define IDX (LIGHT_TWOSIDE|LIGHT_MATERIAL)
#include "t_vb_lighttmp.h"
static void init_lighting_tables( void )
{
static int done;
if (!done) {
init_light_tab();
init_light_tab_twoside();
init_light_tab_material();
init_light_tab_twoside_material();
done = 1;
}
}
static GLboolean run_lighting( struct gl_context *ctx,
struct tnl_pipeline_stage *stage )
{
struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
TNLcontext *tnl = TNL_CONTEXT(ctx);
struct vertex_buffer *VB = &tnl->vb;
GLvector4f *input = ctx->_NeedEyeCoords ? VB->EyePtr : VB->AttribPtr[_TNL_ATTRIB_POS];
GLuint idx;
if (!ctx->Light.Enabled || ctx->VertexProgram._Current)
return GL_TRUE;
/* Make sure we can talk about position x,y and z:
*/
if (input->size <= 2 && input == VB->AttribPtr[_TNL_ATTRIB_POS]) {
_math_trans_4f( store->Input.data,
VB->AttribPtr[_TNL_ATTRIB_POS]->data,
VB->AttribPtr[_TNL_ATTRIB_POS]->stride,
GL_FLOAT,
VB->AttribPtr[_TNL_ATTRIB_POS]->size,
0,
VB->Count );
if (input->size <= 2) {
/* Clean z.
*/
_mesa_vector4f_clean_elem(&store->Input, VB->Count, 2);
}
if (input->size <= 1) {
/* Clean y.
*/
_mesa_vector4f_clean_elem(&store->Input, VB->Count, 1);
}
input = &store->Input;
}
idx = 0;
if (prepare_materials( ctx, VB, store ))
idx |= LIGHT_MATERIAL;
if (ctx->Light.Model.TwoSide)
idx |= LIGHT_TWOSIDE;
/* The individual functions know about replaying side-effects
* vs. full re-execution.
*/
store->light_func_tab[idx]( ctx, VB, stage, input );
return GL_TRUE;
}
/* Called in place of do_lighting when the light table may have changed.
*/
static void validate_lighting( struct gl_context *ctx,
struct tnl_pipeline_stage *stage )
{
light_func *tab;
if (!ctx->Light.Enabled || ctx->VertexProgram._Current)
return;
if (ctx->Light._NeedVertices) {
if (ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)
tab = _tnl_light_spec_tab;
else
tab = _tnl_light_tab;
}
else {
if (ctx->Light.EnabledList.next == ctx->Light.EnabledList.prev)
tab = _tnl_light_fast_single_tab;
else
tab = _tnl_light_fast_tab;
}
LIGHT_STAGE_DATA(stage)->light_func_tab = tab;
/* This and the above should only be done on _NEW_LIGHT:
*/
TNL_CONTEXT(ctx)->Driver.NotifyMaterialChange( ctx );
}
/* Called the first time stage->run is called. In effect, don't
* allocate data until the first time the stage is run.
*/
static GLboolean init_lighting( struct gl_context *ctx,
struct tnl_pipeline_stage *stage )
{
TNLcontext *tnl = TNL_CONTEXT(ctx);
struct light_stage_data *store;
GLuint size = tnl->vb.Size;
stage
->privatePtr
= malloc(sizeof(*store
)); store = LIGHT_STAGE_DATA(stage);
if (!store)
return GL_FALSE;
/* Do onetime init.
*/
init_lighting_tables();
_mesa_vector4f_alloc( &store->Input, 0, size, 32 );
_mesa_vector4f_alloc( &store->LitColor[0], 0, size, 32 );
_mesa_vector4f_alloc( &store->LitColor[1], 0, size, 32 );
_mesa_vector4f_alloc( &store->LitSecondary[0], 0, size, 32 );
_mesa_vector4f_alloc( &store->LitSecondary[1], 0, size, 32 );
store->LitColor[0].size = 4;
store->LitColor[1].size = 4;
store->LitSecondary[0].size = 3;
store->LitSecondary[1].size = 3;
return GL_TRUE;
}
static void dtr( struct tnl_pipeline_stage *stage )
{
struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
if (store) {
_mesa_vector4f_free( &store->Input );
_mesa_vector4f_free( &store->LitColor[0] );
_mesa_vector4f_free( &store->LitColor[1] );
_mesa_vector4f_free( &store->LitSecondary[0] );
_mesa_vector4f_free( &store->LitSecondary[1] );
stage->privatePtr = NULL;
}
}
const struct tnl_pipeline_stage _tnl_lighting_stage =
{
"lighting", /* name */
NULL, /* private_data */
init_lighting,
dtr, /* destroy */
validate_lighting,
run_lighting
};