blender/intern/cycles/kernel/kernel_accumulate.h
Brecht Van Lommel f99343d3b8 Cycles: Render Passes
Currently supported passes:
* Combined, Z, Normal, Object Index, Material Index, Emission, Environment,
  Diffuse/Glossy/Transmission x Direct/Indirect/Color

Not supported yet:
* UV, Vector, Mist

Only enabled for CPU devices at the moment, will do GPU tweaks tommorrow,
also for environment importance sampling.

Documentation:
http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Passes
2012-01-25 17:23:52 +00:00

284 lines
7.7 KiB
C

/*
* Copyright 2011, Blender Foundation.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
CCL_NAMESPACE_BEGIN
/* BSDF Eval
*
* BSDF evaluation result, split per BSDF type. This is used to accumulate
* render passes separately. */
__device_inline void bsdf_eval_init(BsdfEval *eval, ClosureType type, float3 value, int use_light_pass)
{
#ifdef __PASSES__
eval->use_light_pass = use_light_pass;
if(eval->use_light_pass) {
eval->diffuse = make_float3(0.0f, 0.0f, 0.0f);
eval->glossy = make_float3(0.0f, 0.0f, 0.0f);
eval->transmission = make_float3(0.0f, 0.0f, 0.0f);
eval->transparent = make_float3(0.0f, 0.0f, 0.0f);
if(type == CLOSURE_BSDF_TRANSPARENT_ID)
eval->transparent = value;
else if(CLOSURE_IS_BSDF_DIFFUSE(type))
eval->diffuse = value;
else if(CLOSURE_IS_BSDF_GLOSSY(type))
eval->glossy = value;
else
eval->transmission = value;
}
else
eval->diffuse = value;
#else
*eval = value;
#endif
}
__device_inline void bsdf_eval_accum(BsdfEval *eval, ClosureType type, float3 value)
{
#ifdef __PASSES__
if(eval->use_light_pass) {
if(CLOSURE_IS_BSDF_DIFFUSE(type))
eval->diffuse += value;
else if(CLOSURE_IS_BSDF_GLOSSY(type))
eval->glossy += value;
else
eval->transmission += value;
/* skipping transparent, this function is used by for eval(), will be zero then */
}
else
eval->diffuse += value;
#else
*eval += value;
#endif
}
__device_inline bool bsdf_eval_is_zero(BsdfEval *eval)
{
#ifdef __PASSES__
if(eval->use_light_pass) {
return is_zero(eval->diffuse)
&& is_zero(eval->glossy)
&& is_zero(eval->transmission)
&& is_zero(eval->transparent);
}
else
return is_zero(eval->diffuse);
#else
return is_zero(*eval);
#endif
}
__device_inline void bsdf_eval_mul(BsdfEval *eval, float3 value)
{
#ifdef __PASSES__
if(eval->use_light_pass) {
eval->diffuse *= value;
eval->glossy *= value;
eval->transmission *= value;
/* skipping transparent, this function is used by for eval(), will be zero then */
}
else
eval->diffuse *= value;
#else
*eval *= value;
#endif
}
/* Path Radiance
*
* We accumulate different render passes separately. After summing at the end
* to get the combined result, it should be identical. We definte directly
* visible as the first non-transparent hit, while indirectly visible are the
* bounces after that. */
__device_inline void path_radiance_init(PathRadiance *L, int use_light_pass)
{
/* clear all */
#ifdef __PASSES__
L->use_light_pass = use_light_pass;
if(use_light_pass) {
L->indirect = make_float3(0.0f, 0.0f, 0.0f);
L->direct_throughput = make_float3(0.0f, 0.0f, 0.0f);
L->direct_emission = make_float3(0.0f, 0.0f, 0.0f);
L->color_diffuse = make_float3(0.0f, 0.0f, 0.0f);
L->color_glossy = make_float3(0.0f, 0.0f, 0.0f);
L->color_transmission = make_float3(0.0f, 0.0f, 0.0f);
L->direct_diffuse = make_float3(0.0f, 0.0f, 0.0f);
L->direct_glossy = make_float3(0.0f, 0.0f, 0.0f);
L->direct_transmission = make_float3(0.0f, 0.0f, 0.0f);
L->indirect_diffuse = make_float3(0.0f, 0.0f, 0.0f);
L->indirect_glossy = make_float3(0.0f, 0.0f, 0.0f);
L->indirect_transmission = make_float3(0.0f, 0.0f, 0.0f);
L->emission = make_float3(0.0f, 0.0f, 0.0f);
L->background = make_float3(0.0f, 0.0f, 0.0f);
}
else
L->emission = make_float3(0.0f, 0.0f, 0.0f);
#else
*L = make_float3(0.0f, 0.0f, 0.0f);
#endif
}
__device_inline void path_radiance_bsdf_bounce(PathRadiance *L, float3 *throughput,
BsdfEval *bsdf_eval, float bsdf_pdf, int bounce, int bsdf_label)
{
float inverse_pdf = 1.0f/bsdf_pdf;
#ifdef __PASSES__
if(L->use_light_pass) {
if(bounce == 0) {
if(bsdf_label & LABEL_TRANSPARENT) {
/* transparent bounce before first hit */
*throughput *= bsdf_eval->transparent*inverse_pdf;
}
else {
/* first on directly visible surface */
float3 value = *throughput*inverse_pdf;
L->indirect_diffuse = bsdf_eval->diffuse*value;
L->indirect_glossy = bsdf_eval->glossy*value;
L->indirect_transmission = bsdf_eval->transmission*value;
*throughput = L->indirect_diffuse + L->indirect_glossy + L->indirect_transmission;
L->direct_throughput = *throughput;
}
}
else {
/* indirectly visible through BSDF */
float3 sum = (bsdf_eval->diffuse + bsdf_eval->glossy + bsdf_eval->transmission + bsdf_eval->transparent)*inverse_pdf;
*throughput *= sum;
}
}
else
*throughput *= bsdf_eval->diffuse*inverse_pdf;
#else
*throughput *= *bsdf_eval*inverse_pdf;
#endif
}
__device_inline void path_radiance_accum_emission(PathRadiance *L, float3 throughput, float3 value, int bounce)
{
#ifdef __PASSES__
if(L->use_light_pass) {
if(bounce == 0)
L->emission += throughput*value;
else if(bounce == 1)
L->direct_emission += throughput*value;
else
L->indirect += throughput*value;
}
else
L->emission += throughput*value;
#else
*L += throughput*value;
#endif
}
__device_inline void path_radiance_accum_light(PathRadiance *L, float3 throughput, BsdfEval *bsdf_eval, int bounce)
{
#ifdef __PASSES__
if(L->use_light_pass) {
if(bounce == 0) {
/* directly visible lighting */
L->direct_diffuse += throughput*bsdf_eval->diffuse;
L->direct_glossy += throughput*bsdf_eval->glossy;
L->direct_transmission += throughput*bsdf_eval->transmission;
}
else {
/* indirectly visible lighting after BSDF bounce */
float3 sum = bsdf_eval->diffuse + bsdf_eval->glossy + bsdf_eval->transmission;
L->indirect += throughput*sum;
}
}
else
L->emission += throughput*bsdf_eval->diffuse;
#else
*L += throughput*(*bsdf_eval);
#endif
}
__device_inline void path_radiance_accum_background(PathRadiance *L, float3 throughput, float3 value, int bounce)
{
#ifdef __PASSES__
if(L->use_light_pass) {
if(bounce == 0)
L->background += throughput*value;
else if(bounce == 1)
L->direct_emission += throughput*value;
else
L->indirect += throughput*value;
}
else
L->emission += throughput*value;
#else
*L += throughput*value;
#endif
}
__device_inline float3 safe_divide_color(float3 a, float3 b)
{
float x, y, z;
x = (b.x != 0.0f)? a.x/b.x: 0.0f;
y = (b.y != 0.0f)? a.y/b.y: 0.0f;
z = (b.z != 0.0f)? a.z/b.z: 0.0f;
return make_float3(x, y, z);
}
__device_inline float3 path_radiance_sum(PathRadiance *L)
{
#ifdef __PASSES__
if(L->use_light_pass) {
/* this division is a bit ugly, but means we only have to keep track of
only a single throughput further along the path, here we recover just
the indirect parth that is not influenced by any particular BSDF type */
L->direct_emission = safe_divide_color(L->direct_emission, L->direct_throughput);
L->direct_diffuse += L->indirect_diffuse*L->direct_emission;
L->direct_glossy += L->indirect_glossy*L->direct_emission;
L->direct_transmission += L->indirect_transmission*L->direct_emission;
L->indirect = safe_divide_color(L->indirect, L->direct_throughput);
L->indirect_diffuse *= L->indirect;
L->indirect_glossy *= L->indirect;
L->indirect_transmission *= L->indirect;
return L->emission + L->background
+ L->direct_diffuse + L->direct_glossy + L->direct_transmission
+ L->indirect_diffuse + L->indirect_glossy + L->indirect_transmission;
}
else
return L->emission;
#else
return *L;
#endif
}
CCL_NAMESPACE_END