blender/intern/cycles/kernel/kernel_adaptive_sampling.h

240 lines
10 KiB
C

/*
* Copyright 2019 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.
*/
#ifndef __KERNEL_ADAPTIVE_SAMPLING_H__
#define __KERNEL_ADAPTIVE_SAMPLING_H__
CCL_NAMESPACE_BEGIN
/* Determines whether to continue sampling a given pixel or if it has sufficiently converged. */
ccl_device void kernel_do_adaptive_stopping(KernelGlobals *kg,
ccl_global float *buffer,
int sample)
{
/* TODO Stefan: Is this better in linear, sRGB or something else? */
float4 I = *((ccl_global float4 *)buffer);
float4 A = *(ccl_global float4 *)(buffer + kernel_data.film.pass_adaptive_aux_buffer);
/* The per pixel error as seen in section 2.1 of
* "A hierarchical automatic stopping condition for Monte Carlo global illumination"
* A small epsilon is added to the divisor to prevent division by zero. */
float error = (fabsf(I.x - A.x) + fabsf(I.y - A.y) + fabsf(I.z - A.z)) /
(sample * 0.0001f + sqrtf(I.x + I.y + I.z));
if (error < kernel_data.integrator.adaptive_threshold * (float)sample) {
/* Set the fourth component to non-zero value to indicate that this pixel has converged. */
buffer[kernel_data.film.pass_adaptive_aux_buffer + 3] += 1.0f;
}
}
/* Adjust the values of an adaptively sampled pixel. */
ccl_device void kernel_adaptive_post_adjust(KernelGlobals *kg,
ccl_global float *buffer,
float sample_multiplier)
{
*(ccl_global float4 *)(buffer) *= sample_multiplier;
/* Scale the aux pass too, this is necessary for progressive rendering to work properly. */
kernel_assert(kernel_data.film.pass_adaptive_aux_buffer);
*(ccl_global float4 *)(buffer + kernel_data.film.pass_adaptive_aux_buffer) *= sample_multiplier;
#ifdef __PASSES__
int flag = kernel_data.film.pass_flag;
if (flag & PASSMASK(NORMAL))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_normal) *= sample_multiplier;
if (flag & PASSMASK(UV))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_uv) *= sample_multiplier;
if (flag & PASSMASK(MOTION)) {
*(ccl_global float4 *)(buffer + kernel_data.film.pass_motion) *= sample_multiplier;
*(ccl_global float *)(buffer + kernel_data.film.pass_motion_weight) *= sample_multiplier;
}
if (kernel_data.film.use_light_pass) {
int light_flag = kernel_data.film.light_pass_flag;
if (light_flag & PASSMASK(MIST))
*(ccl_global float *)(buffer + kernel_data.film.pass_mist) *= sample_multiplier;
/* Shadow pass omitted on purpose. It has its own scale parameter. */
if (light_flag & PASSMASK(DIFFUSE_INDIRECT))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_diffuse_indirect) *= sample_multiplier;
if (light_flag & PASSMASK(GLOSSY_INDIRECT))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_glossy_indirect) *= sample_multiplier;
if (light_flag & PASSMASK(TRANSMISSION_INDIRECT))
*(ccl_global float3 *)(buffer +
kernel_data.film.pass_transmission_indirect) *= sample_multiplier;
if (light_flag & PASSMASK(VOLUME_INDIRECT))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_volume_indirect) *= sample_multiplier;
if (light_flag & PASSMASK(DIFFUSE_DIRECT))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_diffuse_direct) *= sample_multiplier;
if (light_flag & PASSMASK(GLOSSY_DIRECT))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_glossy_direct) *= sample_multiplier;
if (light_flag & PASSMASK(TRANSMISSION_DIRECT))
*(ccl_global float3 *)(buffer +
kernel_data.film.pass_transmission_direct) *= sample_multiplier;
if (light_flag & PASSMASK(VOLUME_DIRECT))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_volume_direct) *= sample_multiplier;
if (light_flag & PASSMASK(EMISSION))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_emission) *= sample_multiplier;
if (light_flag & PASSMASK(BACKGROUND))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_background) *= sample_multiplier;
if (light_flag & PASSMASK(AO))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_ao) *= sample_multiplier;
if (light_flag & PASSMASK(DIFFUSE_COLOR))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_diffuse_color) *= sample_multiplier;
if (light_flag & PASSMASK(GLOSSY_COLOR))
*(ccl_global float3 *)(buffer + kernel_data.film.pass_glossy_color) *= sample_multiplier;
if (light_flag & PASSMASK(TRANSMISSION_COLOR))
*(ccl_global float3 *)(buffer +
kernel_data.film.pass_transmission_color) *= sample_multiplier;
}
#endif
#ifdef __DENOISING_FEATURES__
# define scale_float3_variance(buffer, offset, scale) \
*(buffer + offset) *= scale; \
*(buffer + offset + 1) *= scale; \
*(buffer + offset + 2) *= scale; \
*(buffer + offset + 3) *= scale * scale; \
*(buffer + offset + 4) *= scale * scale; \
*(buffer + offset + 5) *= scale * scale;
# define scale_shadow_variance(buffer, offset, scale) \
*(buffer + offset) *= scale; \
*(buffer + offset + 1) *= scale; \
*(buffer + offset + 2) *= scale * scale;
if (kernel_data.film.pass_denoising_data) {
scale_shadow_variance(
buffer, kernel_data.film.pass_denoising_data + DENOISING_PASS_SHADOW_A, sample_multiplier);
scale_shadow_variance(
buffer, kernel_data.film.pass_denoising_data + DENOISING_PASS_SHADOW_B, sample_multiplier);
if (kernel_data.film.pass_denoising_clean) {
scale_float3_variance(
buffer, kernel_data.film.pass_denoising_data + DENOISING_PASS_COLOR, sample_multiplier);
*(buffer + kernel_data.film.pass_denoising_clean) *= sample_multiplier;
*(buffer + kernel_data.film.pass_denoising_clean + 1) *= sample_multiplier;
*(buffer + kernel_data.film.pass_denoising_clean + 2) *= sample_multiplier;
}
else {
scale_float3_variance(
buffer, kernel_data.film.pass_denoising_data + DENOISING_PASS_COLOR, sample_multiplier);
}
scale_float3_variance(
buffer, kernel_data.film.pass_denoising_data + DENOISING_PASS_NORMAL, sample_multiplier);
scale_float3_variance(
buffer, kernel_data.film.pass_denoising_data + DENOISING_PASS_ALBEDO, sample_multiplier);
*(buffer + kernel_data.film.pass_denoising_data + DENOISING_PASS_DEPTH) *= sample_multiplier;
*(buffer + kernel_data.film.pass_denoising_data + DENOISING_PASS_DEPTH +
1) *= sample_multiplier * sample_multiplier;
}
#endif /* __DENOISING_FEATURES__ */
/* Cryptomatte. */
if (kernel_data.film.cryptomatte_passes) {
int num_slots = 0;
num_slots += (kernel_data.film.cryptomatte_passes & CRYPT_OBJECT) ? 1 : 0;
num_slots += (kernel_data.film.cryptomatte_passes & CRYPT_MATERIAL) ? 1 : 0;
num_slots += (kernel_data.film.cryptomatte_passes & CRYPT_ASSET) ? 1 : 0;
num_slots = num_slots * 2 * kernel_data.film.cryptomatte_depth;
ccl_global float2 *id_buffer = (ccl_global float2 *)(buffer +
kernel_data.film.pass_cryptomatte);
for (int slot = 0; slot < num_slots; slot++) {
id_buffer[slot].y *= sample_multiplier;
}
}
/* AOVs. */
for (int i = 0; i < kernel_data.film.pass_aov_value_num; i++) {
*(buffer + kernel_data.film.pass_aov_value + i) *= sample_multiplier;
}
for (int i = 0; i < kernel_data.film.pass_aov_color_num; i++) {
*((ccl_global float4 *)(buffer + kernel_data.film.pass_aov_color) + i) *= sample_multiplier;
}
}
/* This is a simple box filter in two passes.
* When a pixel demands more adaptive samples, let its neighboring pixels draw more samples too. */
ccl_device bool kernel_do_adaptive_filter_x(KernelGlobals *kg, int y, ccl_global WorkTile *tile)
{
bool any = false;
bool prev = false;
for (int x = tile->x; x < tile->x + tile->w; ++x) {
int index = tile->offset + x + y * tile->stride;
ccl_global float *buffer = tile->buffer + index * kernel_data.film.pass_stride;
ccl_global float4 *aux = (ccl_global float4 *)(buffer +
kernel_data.film.pass_adaptive_aux_buffer);
if ((*aux).w == 0.0f) {
any = true;
if (x > tile->x && !prev) {
index = index - 1;
buffer = tile->buffer + index * kernel_data.film.pass_stride;
aux = (ccl_global float4 *)(buffer + kernel_data.film.pass_adaptive_aux_buffer);
(*aux).w = 0.0f;
}
prev = true;
}
else {
if (prev) {
(*aux).w = 0.0f;
}
prev = false;
}
}
return any;
}
ccl_device bool kernel_do_adaptive_filter_y(KernelGlobals *kg, int x, ccl_global WorkTile *tile)
{
bool prev = false;
bool any = false;
for (int y = tile->y; y < tile->y + tile->h; ++y) {
int index = tile->offset + x + y * tile->stride;
ccl_global float *buffer = tile->buffer + index * kernel_data.film.pass_stride;
ccl_global float4 *aux = (ccl_global float4 *)(buffer +
kernel_data.film.pass_adaptive_aux_buffer);
if ((*aux).w == 0.0f) {
any = true;
if (y > tile->y && !prev) {
index = index - tile->stride;
buffer = tile->buffer + index * kernel_data.film.pass_stride;
aux = (ccl_global float4 *)(buffer + kernel_data.film.pass_adaptive_aux_buffer);
(*aux).w = 0.0f;
}
prev = true;
}
else {
if (prev) {
(*aux).w = 0.0f;
}
prev = false;
}
}
return any;
}
CCL_NAMESPACE_END
#endif /* __KERNEL_ADAPTIVE_SAMPLING_H__ */