blender/intern/cycles/kernel/kernel_shader.h
Brecht Van Lommel fe222643b4 Cycles Volume Render: add volume emission support.
This is done using the existing Emission node and closure (we may add a volume
emission node, not clear yet if it will be needed).

Volume emission only supports indirect light sampling which means it's not very
efficient to make small or far away bright light sources. Using direct light
sampling and MIS would be tricky and probably won't be added anytime soon. Other
renderers don't support this either as far as I know, lamps and ray visibility
tricks may be used instead.
2013-12-28 23:20:53 +01:00

1088 lines
25 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 "closure/volume.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 float3 shader_volume_eval_phase(KernelGlobals *kg, ShaderData *sd,
float3 omega_in, float3 omega_out)
{
#ifdef __MULTI_CLOSURE__
float3 eval = make_float3(0.0f, 0.0f, 0.0f);
float pdf;
for(int i = 0; i< sd->num_closure; i++) {
const ShaderClosure *sc = &sd->closure[i];
if(CLOSURE_IS_VOLUME(sc->type))
eval += volume_eval_phase(sc, omega_in, omega_out, &pdf);
}
return eval;
#else
float pdf;
return volume_eval_phase(&sd->closure, omega_in, omega_out, &pdf);
#endif
}
/* Volume Evaluation */
ccl_device void shader_eval_volume(KernelGlobals *kg, ShaderData *sd,
VolumeStack *stack, float randb, 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;
sd->randb_closure = randb;
#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, randb, 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