blender/intern/cycles/kernel/kernel_sum_all_radiance.cl
George Kyriazis 7f4479da42 Cycles: OpenCL kernel split
This commit contains all the work related on the AMD megakernel split work
which was mainly done by Varun Sundar, George Kyriazis and Lenny Wang, plus
some help from Sergey Sharybin, Martijn Berger, Thomas Dinges and likely
someone else which we're forgetting to mention.

Currently only AMD cards are enabled for the new split kernel, but it is
possible to force split opencl kernel to be used by setting the following
environment variable: CYCLES_OPENCL_SPLIT_KERNEL_TEST=1.

Not all the features are supported yet, and that being said no motion blur,
camera blur, SSS and volumetrics for now. Also transparent shadows are
disabled on AMD device because of some compiler bug.

This kernel is also only implements regular path tracing and supporting
branched one will take a bit. Branched path tracing is exposed to the
interface still, which is a bit misleading and will be hidden there soon.

More feature will be enabled once they're ported to the split kernel and
tested.

Neither regular CPU nor CUDA has any difference, they're generating the
same exact code, which means no regressions/improvements there.

Based on the research paper:

  https://research.nvidia.com/sites/default/files/publications/laine2013hpg_paper.pdf

Here's the documentation:

  https://docs.google.com/document/d/1LuXW-CV-sVJkQaEGZlMJ86jZ8FmoPfecaMdR-oiWbUY/edit

Design discussion of the patch:

  https://developer.blender.org/T44197

Differential Revision: https://developer.blender.org/D1200
2015-05-09 19:52:40 +05:00

60 lines
2.3 KiB
Common Lisp

/*
* Copyright 2011-2015 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.
*/
#include "kernel_compat_opencl.h"
#include "kernel_math.h"
#include "kernel_types.h"
#include "kernel_globals.h"
/*
* Since we process various samples in parallel; The output radiance of different samples
* are stored in different locations; This kernel combines the output radiance contributed
* by all different samples and stores them in the RenderTile's output buffer.
*/
__kernel void kernel_ocl_path_trace_sum_all_radiance(
ccl_constant KernelData *data, /* To get pass_stride to offet into buffer */
ccl_global float *buffer, /* Output buffer of RenderTile */
ccl_global float *per_sample_output_buffer, /* Radiance contributed by all samples */
int parallel_samples, int sw, int sh, int stride,
int buffer_offset_x,
int buffer_offset_y,
int buffer_stride,
int start_sample)
{
int x = get_global_id(0);
int y = get_global_id(1);
if(x < sw && y < sh) {
buffer += ((buffer_offset_x + x) + (buffer_offset_y + y) * buffer_stride) * (data->film.pass_stride);
per_sample_output_buffer += ((x + y * stride) * parallel_samples) * (data->film.pass_stride);
int sample_stride = (data->film.pass_stride);
int sample_iterator = 0;
int pass_stride_iterator = 0;
int num_floats = data->film.pass_stride;
for(sample_iterator = 0; sample_iterator < parallel_samples; sample_iterator++) {
for(pass_stride_iterator = 0; pass_stride_iterator < num_floats; pass_stride_iterator++) {
*(buffer + pass_stride_iterator) = (start_sample == 0 && sample_iterator == 0) ? *(per_sample_output_buffer + pass_stride_iterator)
: *(buffer + pass_stride_iterator) + *(per_sample_output_buffer + pass_stride_iterator);
}
per_sample_output_buffer += sample_stride;
}
}
}