blender/intern/cycles/kernel/kernel_shader.h

1169 lines
27 KiB
C

/*
* Copyright 2011-2013 Blender Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License
*/
/*
* ShaderData, used in four steps:
*
* Setup from incoming ray, sampled position and background.
* Execute for surface, volume or displacement.
* Evaluate one or more closures.
* Release.
*
*/
#include "closure/bsdf_util.h"
#include "closure/bsdf.h"
#include "closure/emissive.h"
#include "svm/svm.h"
CCL_NAMESPACE_BEGIN
/* ShaderData setup from incoming ray */
#ifdef __OBJECT_MOTION__
ccl_device void shader_setup_object_transforms(KernelGlobals *kg, ShaderData *sd, float time)
{
if(sd->flag & SD_OBJECT_MOTION) {
sd->ob_tfm = object_fetch_transform_motion(kg, sd->object, time);
sd->ob_itfm= transform_quick_inverse(sd->ob_tfm);
}
else {
sd->ob_tfm = object_fetch_transform(kg, sd->object, OBJECT_TRANSFORM);
sd->ob_itfm = object_fetch_transform(kg, sd->object, OBJECT_INVERSE_TRANSFORM);
}
}
#endif
ccl_device void shader_setup_from_ray(KernelGlobals *kg, ShaderData *sd,
const Intersection *isect, const Ray *ray, int bounce)
{
#ifdef __INSTANCING__
sd->object = (isect->object == ~0)? kernel_tex_fetch(__prim_object, isect->prim): isect->object;
#endif
sd->flag = kernel_tex_fetch(__object_flag, sd->object);
/* matrices and time */
#ifdef __OBJECT_MOTION__
shader_setup_object_transforms(kg, sd, ray->time);
sd->time = ray->time;
#endif
sd->prim = kernel_tex_fetch(__prim_index, isect->prim);
sd->ray_length = isect->t;
sd->ray_depth = bounce;
#ifdef __HAIR__
if(kernel_tex_fetch(__prim_segment, isect->prim) != ~0) {
/* Strand Shader setting*/
float4 curvedata = kernel_tex_fetch(__curves, sd->prim);
sd->shader = __float_as_int(curvedata.z);
sd->segment = isect->segment;
sd->P = bvh_curve_refine(kg, sd, isect, ray);
}
else {
#endif
/* fetch triangle data */
float4 Ns = kernel_tex_fetch(__tri_normal, sd->prim);
float3 Ng = make_float3(Ns.x, Ns.y, Ns.z);
sd->shader = __float_as_int(Ns.w);
#ifdef __HAIR__
sd->segment = ~0;
/*elements for minimum hair width using transparency bsdf*/
/*sd->curve_transparency = 0.0f;*/
/*sd->curve_radius = 0.0f;*/
#endif
#ifdef __UV__
sd->u = isect->u;
sd->v = isect->v;
#endif
/* vectors */
sd->P = bvh_triangle_refine(kg, sd, isect, ray);
sd->Ng = Ng;
sd->N = Ng;
/* smooth normal */
if(sd->shader & SHADER_SMOOTH_NORMAL)
sd->N = triangle_smooth_normal(kg, sd->prim, sd->u, sd->v);
#ifdef __DPDU__
/* dPdu/dPdv */
triangle_dPdudv(kg, &sd->dPdu, &sd->dPdv, sd->prim);
#endif
#ifdef __HAIR__
}
#endif
sd->I = -ray->D;
sd->flag |= kernel_tex_fetch(__shader_flag, (sd->shader & SHADER_MASK)*2);
#ifdef __INSTANCING__
if(isect->object != ~0) {
/* instance transform */
object_normal_transform(kg, sd, &sd->N);
object_normal_transform(kg, sd, &sd->Ng);
#ifdef __DPDU__
object_dir_transform(kg, sd, &sd->dPdu);
object_dir_transform(kg, sd, &sd->dPdv);
#endif
}
#endif
/* backfacing test */
bool backfacing = (dot(sd->Ng, sd->I) < 0.0f);
if(backfacing) {
sd->flag |= SD_BACKFACING;
sd->Ng = -sd->Ng;
sd->N = -sd->N;
#ifdef __DPDU__
sd->dPdu = -sd->dPdu;
sd->dPdv = -sd->dPdv;
#endif
}
#ifdef __RAY_DIFFERENTIALS__
/* differentials */
differential_transfer(&sd->dP, ray->dP, ray->D, ray->dD, sd->Ng, isect->t);
differential_incoming(&sd->dI, ray->dD);
differential_dudv(&sd->du, &sd->dv, sd->dPdu, sd->dPdv, sd->dP, sd->Ng);
#endif
}
/* ShaderData setup from BSSRDF scatter */
#ifdef __SUBSURFACE__
ccl_device_inline void shader_setup_from_subsurface(KernelGlobals *kg, ShaderData *sd,
const Intersection *isect, const Ray *ray)
{
bool backfacing = sd->flag & SD_BACKFACING;
/* object, matrices, time, ray_length stay the same */
sd->flag = kernel_tex_fetch(__object_flag, sd->object);
sd->prim = kernel_tex_fetch(__prim_index, isect->prim);
/* fetch triangle data */
float4 Ns = kernel_tex_fetch(__tri_normal, sd->prim);
float3 Ng = make_float3(Ns.x, Ns.y, Ns.z);
sd->shader = __float_as_int(Ns.w);
#ifdef __HAIR__
sd->segment = ~0;
#endif
#ifdef __UV__
sd->u = isect->u;
sd->v = isect->v;
#endif
/* vectors */
sd->P = bvh_triangle_refine_subsurface(kg, sd, isect, ray);
sd->Ng = Ng;
sd->N = Ng;
/* smooth normal */
if(sd->shader & SHADER_SMOOTH_NORMAL)
sd->N = triangle_smooth_normal(kg, sd->prim, sd->u, sd->v);
#ifdef __DPDU__
/* dPdu/dPdv */
triangle_dPdudv(kg, &sd->dPdu, &sd->dPdv, sd->prim);
#endif
sd->flag |= kernel_tex_fetch(__shader_flag, (sd->shader & SHADER_MASK)*2);
#ifdef __INSTANCING__
if(isect->object != ~0) {
/* instance transform */
object_normal_transform(kg, sd, &sd->N);
object_normal_transform(kg, sd, &sd->Ng);
#ifdef __DPDU__
object_dir_transform(kg, sd, &sd->dPdu);
object_dir_transform(kg, sd, &sd->dPdv);
#endif
}
#endif
/* backfacing test */
if(backfacing) {
sd->flag |= SD_BACKFACING;
sd->Ng = -sd->Ng;
sd->N = -sd->N;
#ifdef __DPDU__
sd->dPdu = -sd->dPdu;
sd->dPdv = -sd->dPdv;
#endif
}
/* should not get used in principle as the shading will only use a diffuse
* BSDF, but the shader might still access it */
sd->I = sd->N;
#ifdef __RAY_DIFFERENTIALS__
/* differentials */
differential_dudv(&sd->du, &sd->dv, sd->dPdu, sd->dPdv, sd->dP, sd->Ng);
/* don't modify dP and dI */
#endif
}
#endif
/* ShaderData setup from position sampled on mesh */
ccl_device void shader_setup_from_sample(KernelGlobals *kg, ShaderData *sd,
const float3 P, const float3 Ng, const float3 I,
int shader, int object, int prim, float u, float v, float t, float time, int bounce, int segment)
{
/* vectors */
sd->P = P;
sd->N = Ng;
sd->Ng = Ng;
sd->I = I;
sd->shader = shader;
#ifdef __HAIR__
sd->segment = segment;
#endif
/* primitive */
#ifdef __INSTANCING__
sd->object = object;
#endif
/* currently no access to bvh prim index for strand sd->prim*/
sd->prim = prim;
#ifdef __UV__
sd->u = u;
sd->v = v;
#endif
sd->ray_length = t;
sd->ray_depth = bounce;
/* detect instancing, for non-instanced the object index is -object-1 */
#ifdef __INSTANCING__
bool instanced = false;
if(sd->prim != ~0) {
if(sd->object >= 0)
instanced = true;
else
#endif
sd->object = ~sd->object;
#ifdef __INSTANCING__
}
#endif
sd->flag = kernel_tex_fetch(__shader_flag, (sd->shader & SHADER_MASK)*2);
if(sd->object != -1) {
sd->flag |= kernel_tex_fetch(__object_flag, sd->object);
#ifdef __OBJECT_MOTION__
shader_setup_object_transforms(kg, sd, time);
}
sd->time = time;
#else
}
#endif
/* smooth normal */
#ifdef __HAIR__
if(sd->shader & SHADER_SMOOTH_NORMAL && sd->segment == ~0) {
sd->N = triangle_smooth_normal(kg, sd->prim, sd->u, sd->v);
#else
if(sd->shader & SHADER_SMOOTH_NORMAL) {
sd->N = triangle_smooth_normal(kg, sd->prim, sd->u, sd->v);
#endif
#ifdef __INSTANCING__
if(instanced)
object_normal_transform(kg, sd, &sd->N);
#endif
}
#ifdef __DPDU__
/* dPdu/dPdv */
#ifdef __HAIR__
if(sd->prim == ~0 || sd->segment != ~0) {
sd->dPdu = make_float3(0.0f, 0.0f, 0.0f);
sd->dPdv = make_float3(0.0f, 0.0f, 0.0f);
}
#else
if(sd->prim == ~0) {
sd->dPdu = make_float3(0.0f, 0.0f, 0.0f);
sd->dPdv = make_float3(0.0f, 0.0f, 0.0f);
}
#endif
else {
triangle_dPdudv(kg, &sd->dPdu, &sd->dPdv, sd->prim);
#ifdef __INSTANCING__
if(instanced) {
object_dir_transform(kg, sd, &sd->dPdu);
object_dir_transform(kg, sd, &sd->dPdv);
}
#endif
}
#endif
/* backfacing test */
if(sd->prim != ~0) {
bool backfacing = (dot(sd->Ng, sd->I) < 0.0f);
if(backfacing) {
sd->flag |= SD_BACKFACING;
sd->Ng = -sd->Ng;
sd->N = -sd->N;
#ifdef __DPDU__
sd->dPdu = -sd->dPdu;
sd->dPdv = -sd->dPdv;
#endif
}
}
#ifdef __RAY_DIFFERENTIALS__
/* no ray differentials here yet */
sd->dP = differential3_zero();
sd->dI = differential3_zero();
sd->du = differential_zero();
sd->dv = differential_zero();
#endif
}
/* ShaderData setup for displacement */
ccl_device void shader_setup_from_displace(KernelGlobals *kg, ShaderData *sd,
int object, int prim, float u, float v)
{
float3 P, Ng, I = make_float3(0.0f, 0.0f, 0.0f);
int shader;
P = triangle_point_MT(kg, prim, u, v);
Ng = triangle_normal_MT(kg, prim, &shader);
/* force smooth shading for displacement */
shader |= SHADER_SMOOTH_NORMAL;
/* watch out: no instance transform currently */
shader_setup_from_sample(kg, sd, P, Ng, I, shader, object, prim, u, v, 0.0f, TIME_INVALID, 0, ~0);
}
/* ShaderData setup from ray into background */
ccl_device_inline void shader_setup_from_background(KernelGlobals *kg, ShaderData *sd, const Ray *ray, int bounce)
{
/* vectors */
sd->P = ray->D;
sd->N = -ray->D;
sd->Ng = -ray->D;
sd->I = -ray->D;
sd->shader = kernel_data.background.surface_shader;
sd->flag = kernel_tex_fetch(__shader_flag, (sd->shader & SHADER_MASK)*2);
#ifdef __OBJECT_MOTION__
sd->time = ray->time;
#endif
sd->ray_length = 0.0f;
sd->ray_depth = bounce;
#ifdef __INSTANCING__
sd->object = ~0;
#endif
sd->prim = ~0;
#ifdef __UV__
sd->u = 0.0f;
sd->v = 0.0f;
#endif
#ifdef __DPDU__
/* dPdu/dPdv */
sd->dPdu = make_float3(0.0f, 0.0f, 0.0f);
sd->dPdv = make_float3(0.0f, 0.0f, 0.0f);
#endif
#ifdef __RAY_DIFFERENTIALS__
/* differentials */
sd->dP = ray->dD;
differential_incoming(&sd->dI, sd->dP);
sd->du.dx = 0.0f;
sd->du.dy = 0.0f;
sd->dv.dx = 0.0f;
sd->dv.dy = 0.0f;
#endif
}
/* ShaderData setup from point inside volume */
ccl_device_inline void shader_setup_from_volume(KernelGlobals *kg, ShaderData *sd, const Ray *ray, int bounce)
{
/* vectors */
sd->P = ray->P;
sd->N = -ray->D;
sd->Ng = -ray->D;
sd->I = -ray->D;
sd->shader = SHADER_NO_ID;
sd->flag = 0;
#ifdef __OBJECT_MOTION__
sd->time = ray->time;
#endif
sd->ray_length = 0.0f; /* todo: can we set this to some useful value? */
sd->ray_depth = bounce;
#ifdef __INSTANCING__
sd->object = ~0; /* todo: fill this for texture coordinates */
#endif
sd->prim = ~0;
#ifdef __HAIR__
sd->segment = ~0;
#endif
#ifdef __UV__
sd->u = 0.0f;
sd->v = 0.0f;
#endif
#ifdef __DPDU__
/* dPdu/dPdv */
sd->dPdu = make_float3(0.0f, 0.0f, 0.0f);
sd->dPdv = make_float3(0.0f, 0.0f, 0.0f);
#endif
#ifdef __RAY_DIFFERENTIALS__
/* differentials */
sd->dP = ray->dD;
differential_incoming(&sd->dI, sd->dP);
sd->du = differential_zero();
sd->dv = differential_zero();
#endif
/* for NDC coordinates */
sd->ray_P = ray->P;
sd->ray_dP = ray->dP;
}
/* Merging */
#if defined(__BRANCHED_PATH__) || defined(__VOLUME__)
ccl_device void shader_merge_closures(ShaderData *sd)
{
/* merge identical closures, better when we sample a single closure at a time */
for(int i = 0; i < sd->num_closure; i++) {
ShaderClosure *sci = &sd->closure[i];
for(int j = i + 1; j < sd->num_closure; j++) {
ShaderClosure *scj = &sd->closure[j];
#ifdef __OSL__
if(!sci->prim && !scj->prim && sci->type == scj->type && sci->data0 == scj->data0 && sci->data1 == scj->data1) {
#else
if(sci->type == scj->type && sci->data0 == scj->data0 && sci->data1 == scj->data1) {
#endif
sci->weight += scj->weight;
sci->sample_weight += scj->sample_weight;
int size = sd->num_closure - (j+1);
if(size > 0) {
for(int k = 0; k < size; k++) {
scj[k] = scj[k+1];
}
}
sd->num_closure--;
j--;
}
}
}
}
#endif
/* BSDF */
#ifdef __MULTI_CLOSURE__
ccl_device_inline void _shader_bsdf_multi_eval(KernelGlobals *kg, const ShaderData *sd, const float3 omega_in, float *pdf,
int skip_bsdf, BsdfEval *result_eval, float sum_pdf, float sum_sample_weight)
{
/* this is the veach one-sample model with balance heuristic, some pdf
* factors drop out when using balance heuristic weighting */
for(int i = 0; i< sd->num_closure; i++) {
if(i == skip_bsdf)
continue;
const ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_BSDF(sc->type)) {
float bsdf_pdf = 0.0f;
float3 eval = bsdf_eval(kg, sd, sc, omega_in, &bsdf_pdf);
if(bsdf_pdf != 0.0f) {
bsdf_eval_accum(result_eval, sc->type, eval*sc->weight);
sum_pdf += bsdf_pdf*sc->sample_weight;
}
sum_sample_weight += sc->sample_weight;
}
}
*pdf = (sum_sample_weight > 0.0f)? sum_pdf/sum_sample_weight: 0.0f;
}
#endif
ccl_device void shader_bsdf_eval(KernelGlobals *kg, const ShaderData *sd,
const float3 omega_in, BsdfEval *eval, float *pdf)
{
#ifdef __MULTI_CLOSURE__
bsdf_eval_init(eval, NBUILTIN_CLOSURES, make_float3(0.0f, 0.0f, 0.0f), kernel_data.film.use_light_pass);
_shader_bsdf_multi_eval(kg, sd, omega_in, pdf, -1, eval, 0.0f, 0.0f);
#else
const ShaderClosure *sc = &sd->closure;
*pdf = 0.0f;
*eval = bsdf_eval(kg, sd, sc, omega_in, pdf)*sc->weight;
#endif
}
ccl_device int shader_bsdf_sample(KernelGlobals *kg, const ShaderData *sd,
float randu, float randv, BsdfEval *bsdf_eval,
float3 *omega_in, differential3 *domega_in, float *pdf)
{
#ifdef __MULTI_CLOSURE__
int sampled = 0;
if(sd->num_closure > 1) {
/* pick a BSDF closure based on sample weights */
float sum = 0.0f;
for(sampled = 0; sampled < sd->num_closure; sampled++) {
const ShaderClosure *sc = &sd->closure[sampled];
if(CLOSURE_IS_BSDF(sc->type))
sum += sc->sample_weight;
}
float r = sd->randb_closure*sum;
sum = 0.0f;
for(sampled = 0; sampled < sd->num_closure; sampled++) {
const ShaderClosure *sc = &sd->closure[sampled];
if(CLOSURE_IS_BSDF(sc->type)) {
sum += sc->sample_weight;
if(r <= sum)
break;
}
}
if(sampled == sd->num_closure) {
*pdf = 0.0f;
return LABEL_NONE;
}
}
const ShaderClosure *sc = &sd->closure[sampled];
int label;
float3 eval;
*pdf = 0.0f;
label = bsdf_sample(kg, sd, sc, randu, randv, &eval, omega_in, domega_in, pdf);
if(*pdf != 0.0f) {
bsdf_eval_init(bsdf_eval, sc->type, eval*sc->weight, kernel_data.film.use_light_pass);
if(sd->num_closure > 1) {
float sweight = sc->sample_weight;
_shader_bsdf_multi_eval(kg, sd, *omega_in, pdf, sampled, bsdf_eval, *pdf*sweight, sweight);
}
}
return label;
#else
/* sample the single closure that we picked */
*pdf = 0.0f;
int label = bsdf_sample(kg, sd, &sd->closure, randu, randv, bsdf_eval, omega_in, domega_in, pdf);
*bsdf_eval *= sd->closure.weight;
return label;
#endif
}
ccl_device int shader_bsdf_sample_closure(KernelGlobals *kg, const ShaderData *sd,
const ShaderClosure *sc, float randu, float randv, BsdfEval *bsdf_eval,
float3 *omega_in, differential3 *domega_in, float *pdf)
{
int label;
float3 eval;
*pdf = 0.0f;
label = bsdf_sample(kg, sd, sc, randu, randv, &eval, omega_in, domega_in, pdf);
if(*pdf != 0.0f)
bsdf_eval_init(bsdf_eval, sc->type, eval*sc->weight, kernel_data.film.use_light_pass);
return label;
}
ccl_device void shader_bsdf_blur(KernelGlobals *kg, ShaderData *sd, float roughness)
{
#ifdef __MULTI_CLOSURE__
for(int i = 0; i< sd->num_closure; i++) {
ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_BSDF(sc->type))
bsdf_blur(kg, sc, roughness);
}
#else
bsdf_blur(kg, &sd->closure, roughness);
#endif
}
ccl_device float3 shader_bsdf_transparency(KernelGlobals *kg, ShaderData *sd)
{
#ifdef __MULTI_CLOSURE__
float3 eval = make_float3(0.0f, 0.0f, 0.0f);
for(int i = 0; i< sd->num_closure; i++) {
ShaderClosure *sc = &sd->closure[i];
if(sc->type == CLOSURE_BSDF_TRANSPARENT_ID) // todo: make this work for osl
eval += sc->weight;
}
return eval;
#else
if(sd->closure.type == CLOSURE_BSDF_TRANSPARENT_ID)
return sd->closure.weight;
else
return make_float3(0.0f, 0.0f, 0.0f);
#endif
}
ccl_device float3 shader_bsdf_alpha(KernelGlobals *kg, ShaderData *sd)
{
float3 alpha = make_float3(1.0f, 1.0f, 1.0f) - shader_bsdf_transparency(kg, sd);
alpha = max(alpha, make_float3(0.0f, 0.0f, 0.0f));
alpha = min(alpha, make_float3(1.0f, 1.0f, 1.0f));
return alpha;
}
ccl_device float3 shader_bsdf_diffuse(KernelGlobals *kg, ShaderData *sd)
{
#ifdef __MULTI_CLOSURE__
float3 eval = make_float3(0.0f, 0.0f, 0.0f);
for(int i = 0; i< sd->num_closure; i++) {
ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_BSDF_DIFFUSE(sc->type))
eval += sc->weight;
}
return eval;
#else
if(CLOSURE_IS_BSDF_DIFFUSE(sd->closure.type))
return sd->closure.weight;
else
return make_float3(0.0f, 0.0f, 0.0f);
#endif
}
ccl_device float3 shader_bsdf_glossy(KernelGlobals *kg, ShaderData *sd)
{
#ifdef __MULTI_CLOSURE__
float3 eval = make_float3(0.0f, 0.0f, 0.0f);
for(int i = 0; i< sd->num_closure; i++) {
ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_BSDF_GLOSSY(sc->type))
eval += sc->weight;
}
return eval;
#else
if(CLOSURE_IS_BSDF_GLOSSY(sd->closure.type))
return sd->closure.weight;
else
return make_float3(0.0f, 0.0f, 0.0f);
#endif
}
ccl_device float3 shader_bsdf_transmission(KernelGlobals *kg, ShaderData *sd)
{
#ifdef __MULTI_CLOSURE__
float3 eval = make_float3(0.0f, 0.0f, 0.0f);
for(int i = 0; i< sd->num_closure; i++) {
ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_BSDF_TRANSMISSION(sc->type))
eval += sc->weight;
}
return eval;
#else
if(CLOSURE_IS_BSDF_TRANSMISSION(sd->closure.type))
return sd->closure.weight;
else
return make_float3(0.0f, 0.0f, 0.0f);
#endif
}
ccl_device float3 shader_bsdf_subsurface(KernelGlobals *kg, ShaderData *sd)
{
#ifdef __MULTI_CLOSURE__
float3 eval = make_float3(0.0f, 0.0f, 0.0f);
for(int i = 0; i< sd->num_closure; i++) {
ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_BSSRDF(sc->type))
eval += sc->weight;
}
return eval;
#else
if(CLOSURE_IS_BSSRDF(sd->closure.type))
return sd->closure.weight;
else
return make_float3(0.0f, 0.0f, 0.0f);
#endif
}
ccl_device float3 shader_bsdf_ao(KernelGlobals *kg, ShaderData *sd, float ao_factor, float3 *N_)
{
#ifdef __MULTI_CLOSURE__
float3 eval = make_float3(0.0f, 0.0f, 0.0f);
float3 N = make_float3(0.0f, 0.0f, 0.0f);
for(int i = 0; i< sd->num_closure; i++) {
ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_BSDF_DIFFUSE(sc->type)) {
eval += sc->weight*ao_factor;
N += sc->N*average(sc->weight);
}
else if(CLOSURE_IS_AMBIENT_OCCLUSION(sc->type)) {
eval += sc->weight;
N += sd->N*average(sc->weight);
}
}
if(is_zero(N))
N = sd->N;
else
N = normalize(N);
*N_ = N;
return eval;
#else
*N_ = sd->N;
if(CLOSURE_IS_BSDF_DIFFUSE(sd->closure.type))
return sd->closure.weight*ao_factor;
else if(CLOSURE_IS_AMBIENT_OCCLUSION(sd->closure.type))
return sd->closure.weight;
else
return make_float3(0.0f, 0.0f, 0.0f);
#endif
}
ccl_device float3 shader_bssrdf_sum(ShaderData *sd, float3 *N_, float *texture_blur_)
{
#ifdef __MULTI_CLOSURE__
float3 eval = make_float3(0.0f, 0.0f, 0.0f);
float3 N = make_float3(0.0f, 0.0f, 0.0f);
float texture_blur = 0.0f, weight_sum = 0.0f;
for(int i = 0; i< sd->num_closure; i++) {
ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_BSSRDF(sc->type)) {
float avg_weight = fabsf(average(sc->weight));
N += sc->N*avg_weight;
eval += sc->weight;
texture_blur += sc->data1*avg_weight;
weight_sum += avg_weight;
}
}
if(N_)
*N_ = (is_zero(N))? sd->N: normalize(N);
if(texture_blur_)
*texture_blur_ = texture_blur/weight_sum;
return eval;
#else
if(CLOSURE_IS_BSSRDF(sd->closure.type)) {
if(N_) *N_ = sd->closure.N;
if(texture_blur_) *texture_blur_ = sd->closure.data1;
return sd->closure.weight;
}
else {
if(N_) *N_ = sd->N;
if(texture_blur_) *texture_blur_ = 0.0f;
return make_float3(0.0f, 0.0f, 0.0f);
}
#endif
}
/* Emission */
ccl_device float3 emissive_eval(KernelGlobals *kg, ShaderData *sd, ShaderClosure *sc)
{
return emissive_simple_eval(sd->Ng, sd->I);
}
ccl_device float3 shader_emissive_eval(KernelGlobals *kg, ShaderData *sd)
{
float3 eval;
#ifdef __MULTI_CLOSURE__
eval = make_float3(0.0f, 0.0f, 0.0f);
for(int i = 0; i < sd->num_closure; i++) {
ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_EMISSION(sc->type))
eval += emissive_eval(kg, sd, sc)*sc->weight;
}
#else
eval = emissive_eval(kg, sd, &sd->closure)*sd->closure.weight;
#endif
return eval;
}
/* Holdout */
ccl_device float3 shader_holdout_eval(KernelGlobals *kg, ShaderData *sd)
{
#ifdef __MULTI_CLOSURE__
float3 weight = make_float3(0.0f, 0.0f, 0.0f);
for(int i = 0; i < sd->num_closure; i++) {
ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_HOLDOUT(sc->type))
weight += sc->weight;
}
return weight;
#else
if(sd->closure.type == CLOSURE_HOLDOUT_ID)
return make_float3(1.0f, 1.0f, 1.0f);
return make_float3(0.0f, 0.0f, 0.0f);
#endif
}
/* Surface Evaluation */
ccl_device void shader_eval_surface(KernelGlobals *kg, ShaderData *sd,
float randb, int path_flag, ShaderContext ctx)
{
#ifdef __MULTI_CLOSURE__
sd->num_closure = 0;
sd->randb_closure = randb;
#else
sd->closure.type = NBUILTIN_CLOSURES;
#endif
#ifdef __OSL__
if(kg->osl)
OSLShader::eval_surface(kg, sd, path_flag, ctx);
else
#endif
{
#ifdef __SVM__
svm_eval_nodes(kg, sd, SHADER_TYPE_SURFACE, randb, path_flag);
#else
sd->closure.weight = make_float3(0.8f, 0.8f, 0.8f);
sd->closure.N = sd->N;
sd->flag |= bsdf_diffuse_setup(&sd->closure);
#endif
}
}
/* Background Evaluation */
ccl_device float3 shader_eval_background(KernelGlobals *kg, ShaderData *sd, int path_flag, ShaderContext ctx)
{
#ifdef __MULTI_CLOSURE__
sd->num_closure = 0;
sd->randb_closure = 0.0f;
#else
sd->closure.type = NBUILTIN_CLOSURES;
#endif
#ifdef __OSL__
if(kg->osl) {
return OSLShader::eval_background(kg, sd, path_flag, ctx);
}
else
#endif
{
#ifdef __SVM__
svm_eval_nodes(kg, sd, SHADER_TYPE_SURFACE, 0.0f, path_flag);
#ifdef __MULTI_CLOSURE__
float3 eval = make_float3(0.0f, 0.0f, 0.0f);
for(int i = 0; i< sd->num_closure; i++) {
const ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_BACKGROUND(sc->type))
eval += sc->weight;
}
return eval;
#else
if(sd->closure.type == CLOSURE_BACKGROUND_ID)
return sd->closure.weight;
else
return make_float3(0.0f, 0.0f, 0.0f);
#endif
#else
return make_float3(0.8f, 0.8f, 0.8f);
#endif
}
}
/* Volume */
#ifdef __VOLUME__
ccl_device_inline void _shader_volume_phase_multi_eval(const ShaderData *sd, const float3 omega_in, float *pdf,
int skip_phase, BsdfEval *result_eval, float sum_pdf, float sum_sample_weight)
{
for(int i = 0; i< sd->num_closure; i++) {
if(i == skip_phase)
continue;
const ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_PHASE(sc->type)) {
float phase_pdf = 0.0f;
float3 eval = volume_phase_eval(sd, sc, omega_in, &phase_pdf);
if(phase_pdf != 0.0f) {
bsdf_eval_accum(result_eval, sc->type, eval);
sum_pdf += phase_pdf;
}
sum_sample_weight += sc->sample_weight;
}
}
*pdf = (sum_sample_weight > 0.0f)? sum_pdf/sum_sample_weight: 0.0f;
}
ccl_device void shader_volume_phase_eval(KernelGlobals *kg, const ShaderData *sd,
const float3 omega_in, BsdfEval *eval, float *pdf)
{
bsdf_eval_init(eval, NBUILTIN_CLOSURES, make_float3(0.0f, 0.0f, 0.0f), kernel_data.film.use_light_pass);
_shader_volume_phase_multi_eval(sd, omega_in, pdf, -1, eval, 0.0f, 0.0f);
}
ccl_device int shader_volume_phase_sample(KernelGlobals *kg, const ShaderData *sd,
float randu, float randv, BsdfEval *phase_eval,
float3 *omega_in, differential3 *domega_in, float *pdf)
{
int sampled = 0;
if(sd->num_closure > 1) {
/* pick a phase closure based on sample weights */
float sum = 0.0f;
for(sampled = 0; sampled < sd->num_closure; sampled++) {
const ShaderClosure *sc = &sd->closure[sampled];
if(CLOSURE_IS_PHASE(sc->type))
sum += sc->sample_weight;
}
float r = sd->randb_closure*sum;
sum = 0.0f;
for(sampled = 0; sampled < sd->num_closure; sampled++) {
const ShaderClosure *sc = &sd->closure[sampled];
if(CLOSURE_IS_PHASE(sc->type)) {
sum += sc->sample_weight;
if(r <= sum)
break;
}
}
if(sampled == sd->num_closure) {
*pdf = 0.0f;
return LABEL_NONE;
}
}
/* todo: this isn't quite correct, we don't weight anisotropy properly
* depending on color channels, even if this is perhaps not a common case */
const ShaderClosure *sc = &sd->closure[sampled];
int label;
float3 eval;
*pdf = 0.0f;
label = volume_phase_sample(sd, sc, randu, randv, &eval, omega_in, domega_in, pdf);
if(*pdf != 0.0f) {
bsdf_eval_init(phase_eval, sc->type, eval, kernel_data.film.use_light_pass);
}
return label;
}
ccl_device int shader_phase_sample_closure(KernelGlobals *kg, const ShaderData *sd,
const ShaderClosure *sc, float randu, float randv, BsdfEval *phase_eval,
float3 *omega_in, differential3 *domega_in, float *pdf)
{
int label;
float3 eval;
*pdf = 0.0f;
label = volume_phase_sample(sd, sc, randu, randv, &eval, omega_in, domega_in, pdf);
if(*pdf != 0.0f)
bsdf_eval_init(phase_eval, sc->type, eval, kernel_data.film.use_light_pass);
return label;
}
/* Volume Evaluation */
ccl_device void shader_eval_volume(KernelGlobals *kg, ShaderData *sd,
VolumeStack *stack, int path_flag, ShaderContext ctx)
{
/* reset closures once at the start, we will be accumulating the closures
* for all volumes in the stack into a single array of closures */
#ifdef __MULTI_CLOSURE__
sd->num_closure = 0;
#else
sd->closure.type = NBUILTIN_CLOSURES;
#endif
sd->flag = 0;
for(int i = 0; stack[i].shader != SHADER_NO_ID; i++) {
/* setup shaderdata from stack. it's mostly setup already in
* shader_setup_from_volume, this switching should be quick */
sd->object = stack[i].object;
sd->shader = stack[i].shader;
sd->flag &= ~(SD_SHADER_FLAGS|SD_OBJECT_FLAGS);
sd->flag |= kernel_tex_fetch(__shader_flag, (sd->shader & SHADER_MASK)*2);
if(sd->object != ~0) {
sd->flag |= kernel_tex_fetch(__object_flag, sd->object);
#ifdef __OBJECT_MOTION__
/* todo: this is inefficient for motion blur, we should be
* caching matrices instead of recomputing them each step */
shader_setup_object_transforms(kg, sd, sd->time);
#endif
}
/* evaluate shader */
#ifdef __SVM__
#ifdef __OSL__
if(kg->osl) {
OSLShader::eval_volume(kg, sd, path_flag, ctx);
}
else
#endif
{
svm_eval_nodes(kg, sd, SHADER_TYPE_VOLUME, 0.0f, path_flag);
}
#endif
/* merge closures to avoid exceeding number of closures limit */
if(i > 0)
shader_merge_closures(sd);
}
}
#endif
/* Displacement Evaluation */
ccl_device void shader_eval_displacement(KernelGlobals *kg, ShaderData *sd, ShaderContext ctx)
{
#ifdef __MULTI_CLOSURE__
sd->num_closure = 0;
sd->randb_closure = 0.0f;
#else
sd->closure.type = NBUILTIN_CLOSURES;
#endif
/* this will modify sd->P */
#ifdef __SVM__
#ifdef __OSL__
if(kg->osl)
OSLShader::eval_displacement(kg, sd, ctx);
else
#endif
{
svm_eval_nodes(kg, sd, SHADER_TYPE_DISPLACEMENT, 0.0f, 0);
}
#endif
}
/* Transparent Shadows */
#ifdef __TRANSPARENT_SHADOWS__
ccl_device bool shader_transparent_shadow(KernelGlobals *kg, Intersection *isect)
{
int prim = kernel_tex_fetch(__prim_index, isect->prim);
int shader = 0;
#ifdef __HAIR__
if(kernel_tex_fetch(__prim_segment, isect->prim) == ~0) {
#endif
float4 Ns = kernel_tex_fetch(__tri_normal, prim);
shader = __float_as_int(Ns.w);
#ifdef __HAIR__
}
else {
float4 str = kernel_tex_fetch(__curves, prim);
shader = __float_as_int(str.z);
}
#endif
int flag = kernel_tex_fetch(__shader_flag, (shader & SHADER_MASK)*2);
return (flag & SD_HAS_TRANSPARENT_SHADOW) != 0;
}
#endif
CCL_NAMESPACE_END