/*
* Mesa 3-D graphics library
* Version: 5.1
*
* Copyright (C) 1999-2003 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:
* Brian Paul
* Keith Whitwell <keith@tungstengraphics.com>
*/
#if IDX & LIGHT_TWOSIDE
# define NR_SIDES 2
#else
# define NR_SIDES 1
#endif
/* define TRACE to trace lighting code */
/* #define TRACE 1 */
/*
* ctx is the current context
* VB is the vertex buffer
* stage is the lighting stage-private data
* input is the vector of eye or object-space vertex coordinates
*/
static void TAG(light_rgba_spec)( struct gl_context *ctx,
struct vertex_buffer *VB,
struct tnl_pipeline_stage *stage,
GLvector4f *input )
{
struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
GLfloat (*base)[3] = ctx->Light._BaseColor;
GLfloat sumA[2];
GLuint j;
const GLuint vstride = input->stride;
const GLfloat *vertex = (GLfloat *)input->data;
const GLuint nstride = VB->AttribPtr[_TNL_ATTRIB_NORMAL]->stride;
const GLfloat *normal = (GLfloat *)VB->AttribPtr[_TNL_ATTRIB_NORMAL]->data;
GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
GLfloat (*Fspec)[4] = (GLfloat (*)[4]) store->LitSecondary[0].data;
#if IDX & LIGHT_TWOSIDE
GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
GLfloat (*Bspec)[4] = (GLfloat (*)[4]) store->LitSecondary[1].data;
#endif
const GLuint nr = VB->Count;
#ifdef TRACE
fprintf(stderr, "%s\n", __FUNCTION__ );
#endif
VB->AttribPtr[_TNL_ATTRIB_COLOR0] = &store->LitColor[0];
VB->AttribPtr[_TNL_ATTRIB_COLOR1] = &store->LitSecondary[0];
sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
#if IDX & LIGHT_TWOSIDE
VB->BackfaceColorPtr = &store->LitColor[1];
VB->BackfaceSecondaryColorPtr = &store->LitSecondary[1];
sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
#endif
store->LitColor[0].stride = 16;
store->LitColor[1].stride = 16;
for (j = 0; j < nr; j++,STRIDE_F(vertex,vstride),STRIDE_F(normal,nstride)) {
GLfloat sum[2][3], spec[2][3];
struct gl_light *light;
#if IDX & LIGHT_MATERIAL
update_materials( ctx, store );
sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
#if IDX & LIGHT_TWOSIDE
sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
#endif
#endif
COPY_3V(sum[0], base[0]);
ZERO_3V(spec[0]);
#if IDX & LIGHT_TWOSIDE
COPY_3V(sum[1], base[1]);
ZERO_3V(spec[1]);
#endif
/* Add contribution from each enabled light source */
foreach (light, &ctx->Light.EnabledList) {
GLfloat n_dot_h;
GLfloat correction;
GLint side;
GLfloat contrib[3];
GLfloat attenuation;
GLfloat VP[3]; /* unit vector from vertex to light */
GLfloat n_dot_VP; /* n dot VP */
GLfloat *h;
/* compute VP and attenuation */
if (!(light->_Flags & LIGHT_POSITIONAL)) {
/* directional light */
COPY_3V(VP, light->_VP_inf_norm);
attenuation = light->_VP_inf_spot_attenuation;
}
else {
GLfloat d; /* distance from vertex to light */
SUB_3V(VP, light->_Position, vertex);
d = (GLfloat) LEN_3FV( VP );
if (d > 1e-6) {
GLfloat invd = 1.0F / d;
SELF_SCALE_SCALAR_3V(VP, invd);
}
attenuation = 1.0F / (light->ConstantAttenuation + d *
(light->LinearAttenuation + d *
light->QuadraticAttenuation));
/* spotlight attenuation */
if (light->_Flags & LIGHT_SPOT) {
GLfloat PV_dot_dir = - DOT3(VP, light->_NormSpotDirection);
if (PV_dot_dir<light->_CosCutoff) {
continue; /* this light makes no contribution */
}
else {
GLfloat spot = powf(PV_dot_dir, light->SpotExponent);
attenuation *= spot;
}
}
}
if (attenuation < 1e-3)
continue; /* this light makes no contribution */
/* Compute dot product or normal and vector from V to light pos */
n_dot_VP = DOT3( normal, VP );
/* Which side gets the diffuse & specular terms? */
if (n_dot_VP < 0.0F) {
ACC_SCALE_SCALAR_3V(sum[0], attenuation, light->_MatAmbient[0]);
#if IDX & LIGHT_TWOSIDE
side = 1;
correction = -1;
n_dot_VP = -n_dot_VP;
#else
continue;
#endif
}
else {
#if IDX & LIGHT_TWOSIDE
ACC_SCALE_SCALAR_3V( sum[1], attenuation, light->_MatAmbient[1]);
#endif
side = 0;
correction = 1;
}
/* diffuse term */
COPY_3V(contrib, light->_MatAmbient[side]);
ACC_SCALE_SCALAR_3V(contrib, n_dot_VP, light->_MatDiffuse[side]);
ACC_SCALE_SCALAR_3V(sum[side], attenuation, contrib );
/* specular term - cannibalize VP... */
if (ctx->Light.Model.LocalViewer) {
GLfloat v[3];
COPY_3V(v, vertex);
NORMALIZE_3FV(v);
SUB_3V(VP, VP, v); /* h = VP + VPe */
h = VP;
NORMALIZE_3FV(h);
}
else if (light->_Flags & LIGHT_POSITIONAL) {
h = VP;
ACC_3V(h, ctx->_EyeZDir);
NORMALIZE_3FV(h);
}
else {
h = light->_h_inf_norm;
}
n_dot_h = correction * DOT3(normal, h);
if (n_dot_h > 0.0F) {
GLfloat spec_coef = lookup_shininess(ctx, side, n_dot_h);
if (spec_coef > 1.0e-10) {
spec_coef *= attenuation;
ACC_SCALE_SCALAR_3V( spec[side], spec_coef,
light->_MatSpecular[side]);
}
}
} /*loop over lights*/
COPY_3V( Fcolor[j], sum[0] );
COPY_3V( Fspec[j], spec[0] );
Fcolor[j][3] = sumA[0];
#if IDX & LIGHT_TWOSIDE
COPY_3V( Bcolor[j], sum[1] );
COPY_3V( Bspec[j], spec[1] );
Bcolor[j][3] = sumA[1];
#endif
}
}
static void TAG(light_rgba)( struct gl_context *ctx,
struct vertex_buffer *VB,
struct tnl_pipeline_stage *stage,
GLvector4f *input )
{
struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
GLuint j;
GLfloat (*base)[3] = ctx->Light._BaseColor;
GLfloat sumA[2];
const GLuint vstride = input->stride;
const GLfloat *vertex = (GLfloat *) input->data;
const GLuint nstride = VB->AttribPtr[_TNL_ATTRIB_NORMAL]->stride;
const GLfloat *normal = (GLfloat *)VB->AttribPtr[_TNL_ATTRIB_NORMAL]->data;
GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
#if IDX & LIGHT_TWOSIDE
GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
#endif
const GLuint nr = VB->Count;
#ifdef TRACE
fprintf(stderr, "%s\n", __FUNCTION__ );
#endif
VB->AttribPtr[_TNL_ATTRIB_COLOR0] = &store->LitColor[0];
sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
#if IDX & LIGHT_TWOSIDE
VB->BackfaceColorPtr = &store->LitColor[1];
sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
#endif
store->LitColor[0].stride = 16;
store->LitColor[1].stride = 16;
for (j = 0; j < nr; j++,STRIDE_F(vertex,vstride),STRIDE_F(normal,nstride)) {
GLfloat sum[2][3];
struct gl_light *light;
#if IDX & LIGHT_MATERIAL
update_materials( ctx, store );
sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
#if IDX & LIGHT_TWOSIDE
sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
#endif
#endif
COPY_3V(sum[0], base[0]);
#if IDX & LIGHT_TWOSIDE
COPY_3V(sum[1], base[1]);
#endif
/* Add contribution from each enabled light source */
foreach (light, &ctx->Light.EnabledList) {
GLfloat n_dot_h;
GLfloat correction;
GLint side;
GLfloat contrib[3];
GLfloat attenuation = 1.0;
GLfloat VP[3]; /* unit vector from vertex to light */
GLfloat n_dot_VP; /* n dot VP */
GLfloat *h;
/* compute VP and attenuation */
if (!(light->_Flags & LIGHT_POSITIONAL)) {
/* directional light */
COPY_3V(VP, light->_VP_inf_norm);
attenuation = light->_VP_inf_spot_attenuation;
}
else {
GLfloat d; /* distance from vertex to light */
SUB_3V(VP, light->_Position, vertex);
d = (GLfloat) LEN_3FV( VP );
if ( d > 1e-6) {
GLfloat invd = 1.0F / d;
SELF_SCALE_SCALAR_3V(VP, invd);
}
attenuation = 1.0F / (light->ConstantAttenuation + d *
(light->LinearAttenuation + d *
light->QuadraticAttenuation));
/* spotlight attenuation */
if (light->_Flags & LIGHT_SPOT) {
GLfloat PV_dot_dir = - DOT3(VP, light->_NormSpotDirection);
if (PV_dot_dir<light->_CosCutoff) {
continue; /* this light makes no contribution */
}
else {
GLfloat spot = powf(PV_dot_dir, light->SpotExponent);
attenuation *= spot;
}
}
}
if (attenuation < 1e-3)
continue; /* this light makes no contribution */
/* Compute dot product or normal and vector from V to light pos */
n_dot_VP = DOT3( normal, VP );
/* which side are we lighting? */
if (n_dot_VP < 0.0F) {
ACC_SCALE_SCALAR_3V(sum[0], attenuation, light->_MatAmbient[0]);
#if IDX & LIGHT_TWOSIDE
side = 1;
correction = -1;
n_dot_VP = -n_dot_VP;
#else
continue;
#endif
}
else {
#if IDX & LIGHT_TWOSIDE
ACC_SCALE_SCALAR_3V( sum[1], attenuation, light->_MatAmbient[1]);
#endif
side = 0;
correction = 1;
}
COPY_3V(contrib, light->_MatAmbient[side]);
/* diffuse term */
ACC_SCALE_SCALAR_3V(contrib, n_dot_VP, light->_MatDiffuse[side]);
/* specular term - cannibalize VP... */
{
if (ctx->Light.Model.LocalViewer) {
GLfloat v[3];
COPY_3V(v, vertex);
NORMALIZE_3FV(v);
SUB_3V(VP, VP, v); /* h = VP + VPe */
h = VP;
NORMALIZE_3FV(h);
}
else if (light->_Flags & LIGHT_POSITIONAL) {
h = VP;
ACC_3V(h, ctx->_EyeZDir);
NORMALIZE_3FV(h);
}
else {
h = light->_h_inf_norm;
}
n_dot_h = correction * DOT3(normal, h);
if (n_dot_h > 0.0F) {
GLfloat spec_coef = lookup_shininess(ctx, side, n_dot_h);
ACC_SCALE_SCALAR_3V( contrib, spec_coef,
light->_MatSpecular[side]);
}
}
ACC_SCALE_SCALAR_3V( sum[side], attenuation, contrib );
}
COPY_3V( Fcolor[j], sum[0] );
Fcolor[j][3] = sumA[0];
#if IDX & LIGHT_TWOSIDE
COPY_3V( Bcolor[j], sum[1] );
Bcolor[j][3] = sumA[1];
#endif
}
}
/* As below, but with just a single light.
*/
static void TAG(light_fast_rgba_single)( struct gl_context *ctx,
struct vertex_buffer *VB,
struct tnl_pipeline_stage *stage,
GLvector4f *input )
{
struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
const GLuint nstride = VB->AttribPtr[_TNL_ATTRIB_NORMAL]->stride;
const GLfloat *normal = (GLfloat *)VB->AttribPtr[_TNL_ATTRIB_NORMAL]->data;
GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
#if IDX & LIGHT_TWOSIDE
GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
#endif
const struct gl_light *light = ctx->Light.EnabledList.next;
GLuint j = 0;
GLfloat base[2][4];
#if IDX & LIGHT_MATERIAL
const GLuint nr = VB->Count;
#else
const GLuint nr = VB->AttribPtr[_TNL_ATTRIB_NORMAL]->count;
#endif
#ifdef TRACE
fprintf(stderr, "%s\n", __FUNCTION__ );
#endif
(void) input; /* doesn't refer to Eye or Obj */
VB->AttribPtr[_TNL_ATTRIB_COLOR0] = &store->LitColor[0];
#if IDX & LIGHT_TWOSIDE
VB->BackfaceColorPtr = &store->LitColor[1];
#endif
if (nr > 1) {
store->LitColor[0].stride = 16;
store->LitColor[1].stride = 16;
}
else {
store->LitColor[0].stride = 0;
store->LitColor[1].stride = 0;
}
for (j = 0; j < nr; j++, STRIDE_F(normal,nstride)) {
GLfloat n_dot_VP;
#if IDX & LIGHT_MATERIAL
update_materials( ctx, store );
#endif
/* No attenuation, so incoporate _MatAmbient into base color.
*/
#if !(IDX & LIGHT_MATERIAL)
if ( j == 0 )
#endif
{
COPY_3V(base[0], light->_MatAmbient[0]);
ACC_3V(base[0], ctx->Light._BaseColor[0] );
base[0][3] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
#if IDX & LIGHT_TWOSIDE
COPY_3V(base[1], light->_MatAmbient[1]);
ACC_3V(base[1], ctx->Light._BaseColor[1]);
base[1][3] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
#endif
}
n_dot_VP = DOT3(normal, light->_VP_inf_norm);
if (n_dot_VP < 0.0F) {
#if IDX & LIGHT_TWOSIDE
GLfloat n_dot_h = -DOT3(normal, light->_h_inf_norm);
GLfloat sum[3];
COPY_3V(sum, base[1]);
ACC_SCALE_SCALAR_3V(sum, -n_dot_VP, light->_MatDiffuse[1]);
if (n_dot_h > 0.0F) {
GLfloat spec = lookup_shininess(ctx, 1, n_dot_h);
ACC_SCALE_SCALAR_3V(sum, spec, light->_MatSpecular[1]);
}
COPY_3V(Bcolor[j], sum );
Bcolor[j][3] = base[1][3];
#endif
COPY_4FV(Fcolor[j], base[0]);
}
else {
GLfloat n_dot_h = DOT3(normal, light->_h_inf_norm);
GLfloat sum[3];
COPY_3V(sum, base[0]);
ACC_SCALE_SCALAR_3V(sum, n_dot_VP, light->_MatDiffuse[0]);
if (n_dot_h > 0.0F) {
GLfloat spec = lookup_shininess(ctx, 0, n_dot_h);
ACC_SCALE_SCALAR_3V(sum, spec, light->_MatSpecular[0]);
}
COPY_3V(Fcolor[j], sum );
Fcolor[j][3] = base[0][3];
#if IDX & LIGHT_TWOSIDE
COPY_4FV(Bcolor[j], base[1]);
#endif
}
}
}
/* Light infinite lights
*/
static void TAG(light_fast_rgba)( struct gl_context *ctx,
struct vertex_buffer *VB,
struct tnl_pipeline_stage *stage,
GLvector4f *input )
{
struct light_stage_data *store = LIGHT_STAGE_DATA(stage);
GLfloat sumA[2];
const GLuint nstride = VB->AttribPtr[_TNL_ATTRIB_NORMAL]->stride;
const GLfloat *normal = (GLfloat *)VB->AttribPtr[_TNL_ATTRIB_NORMAL]->data;
GLfloat (*Fcolor)[4] = (GLfloat (*)[4]) store->LitColor[0].data;
#if IDX & LIGHT_TWOSIDE
GLfloat (*Bcolor)[4] = (GLfloat (*)[4]) store->LitColor[1].data;
#endif
GLuint j = 0;
#if IDX & LIGHT_MATERIAL
const GLuint nr = VB->Count;
#else
const GLuint nr = VB->AttribPtr[_TNL_ATTRIB_NORMAL]->count;
#endif
const struct gl_light *light;
#ifdef TRACE
fprintf(stderr, "%s %d\n", __FUNCTION__, nr );
#endif
(void) input;
sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
VB->AttribPtr[_TNL_ATTRIB_COLOR0] = &store->LitColor[0];
#if IDX & LIGHT_TWOSIDE
VB->BackfaceColorPtr = &store->LitColor[1];
#endif
if (nr > 1) {
store->LitColor[0].stride = 16;
store->LitColor[1].stride = 16;
}
else {
store->LitColor[0].stride = 0;
store->LitColor[1].stride = 0;
}
for (j = 0; j < nr; j++, STRIDE_F(normal,nstride)) {
GLfloat sum[2][3];
#if IDX & LIGHT_MATERIAL
update_materials( ctx, store );
sumA[0] = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_DIFFUSE][3];
#if IDX & LIGHT_TWOSIDE
sumA[1] = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_DIFFUSE][3];
#endif
#endif
COPY_3V(sum[0], ctx->Light._BaseColor[0]);
#if IDX & LIGHT_TWOSIDE
COPY_3V(sum[1], ctx->Light._BaseColor[1]);
#endif
foreach (light, &ctx->Light.EnabledList) {
GLfloat n_dot_h, n_dot_VP, spec;
ACC_3V(sum[0], light->_MatAmbient[0]);
#if IDX & LIGHT_TWOSIDE
ACC_3V(sum[1], light->_MatAmbient[1]);
#endif
n_dot_VP = DOT3(normal, light->_VP_inf_norm);
if (n_dot_VP > 0.0F) {
ACC_SCALE_SCALAR_3V(sum[0], n_dot_VP, light->_MatDiffuse[0]);
n_dot_h = DOT3(normal, light->_h_inf_norm);
if (n_dot_h > 0.0F) {
spec = lookup_shininess(ctx, 0, n_dot_h);
ACC_SCALE_SCALAR_3V( sum[0], spec, light->_MatSpecular[0]);
}
}
#if IDX & LIGHT_TWOSIDE
else {
ACC_SCALE_SCALAR_3V(sum[1], -n_dot_VP, light->_MatDiffuse[1]);
n_dot_h = -DOT3(normal, light->_h_inf_norm);
if (n_dot_h > 0.0F) {
spec = lookup_shininess(ctx, 1, n_dot_h);
ACC_SCALE_SCALAR_3V( sum[1], spec, light->_MatSpecular[1]);
}
}
#endif
}
COPY_3V( Fcolor[j], sum[0] );
Fcolor[j][3] = sumA[0];
#if IDX & LIGHT_TWOSIDE
COPY_3V( Bcolor[j], sum[1] );
Bcolor[j][3] = sumA[1];
#endif
}
}
static void TAG(init_light_tab)( void )
{
_tnl_light_tab[IDX] = TAG(light_rgba);
_tnl_light_fast_tab[IDX] = TAG(light_fast_rgba);
_tnl_light_fast_single_tab[IDX] = TAG(light_fast_rgba_single);
_tnl_light_spec_tab[IDX] = TAG(light_rgba_spec);
}
#undef TAG
#undef IDX
#undef NR_SIDES