blender/intern/cycles/render/session.cpp
Brecht Van Lommel b20a7e01d0 Cycles: experimental correlated multi-jittered sampling pattern that can be used
instead of sobol. So far one doesn't seem to be consistently better or worse than
the other for the same number of samples but more testing is needed.

The random number generator itself is slower than sobol for most number of samples,
except 16, 64, 256, .. because they can be computed faster. This can probably be
optimized, but we can do that when/if this actually turns out to be useful.

Paper this implementation is based on:
http://graphics.pixar.com/library/MultiJitteredSampling/

Also includes some refactoring of RNG code, fixing a Sobol correlation issue with
the first BSDF and < 16 samples, skipping some unneeded RNG calls and using a
simpler unit square to unit disk function.
2013-06-07 16:06:22 +00:00

906 lines
21 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.
*/
#include <string.h>
#include <limits.h>
#include "buffers.h"
#include "camera.h"
#include "device.h"
#include "integrator.h"
#include "scene.h"
#include "session.h"
#include "util_foreach.h"
#include "util_function.h"
#include "util_math.h"
#include "util_opengl.h"
#include "util_task.h"
#include "util_time.h"
CCL_NAMESPACE_BEGIN
/* Note about preserve_tile_device option for tile manager:
* progressive refine and viewport rendering does requires tiles to
* always be allocated for the same device
*/
Session::Session(const SessionParams& params_)
: params(params_),
tile_manager(params.progressive, params.samples, params.tile_size, params.start_resolution,
params.background == false || params.progressive_refine, params.background, params.tile_order,
max(params.device.multi_devices.size(), 1)),
stats()
{
device_use_gl = ((params.device.type != DEVICE_CPU) && !params.background);
TaskScheduler::init(params.threads);
device = Device::create(params.device, stats, params.background);
if(params.background) {
buffers = NULL;
display = NULL;
}
else {
buffers = new RenderBuffers(device);
display = new DisplayBuffer(device);
}
session_thread = NULL;
scene = NULL;
start_time = 0.0;
reset_time = 0.0;
preview_time = 0.0;
paused_time = 0.0;
delayed_reset.do_reset = false;
delayed_reset.samples = 0;
display_outdated = false;
gpu_draw_ready = false;
gpu_need_tonemap = false;
pause = false;
kernels_loaded = false;
}
Session::~Session()
{
if(session_thread) {
progress.set_cancel("Exiting");
gpu_need_tonemap = false;
gpu_need_tonemap_cond.notify_all();
{
thread_scoped_lock pause_lock(pause_mutex);
pause = false;
}
pause_cond.notify_all();
wait();
}
if(display && params.output_path != "") {
tonemap();
progress.set_status("Writing Image", params.output_path);
display->write(device, params.output_path);
}
foreach(RenderBuffers *buffers, tile_buffers)
delete buffers;
delete buffers;
delete display;
delete scene;
delete device;
TaskScheduler::exit();
}
void Session::start()
{
session_thread = new thread(function_bind(&Session::run, this));
}
bool Session::ready_to_reset()
{
double dt = time_dt() - reset_time;
if(!display_outdated)
return (dt > params.reset_timeout);
else
return (dt > params.cancel_timeout);
}
/* GPU Session */
void Session::reset_gpu(BufferParams& buffer_params, int samples)
{
thread_scoped_lock pause_lock(pause_mutex);
/* block for buffer acces and reset immediately. we can't do this
* in the thread, because we need to allocate an OpenGL buffer, and
* that only works in the main thread */
thread_scoped_lock display_lock(display_mutex);
thread_scoped_lock buffers_lock(buffers_mutex);
display_outdated = true;
reset_time = time_dt();
reset_(buffer_params, samples);
gpu_need_tonemap = false;
gpu_need_tonemap_cond.notify_all();
pause_cond.notify_all();
}
bool Session::draw_gpu(BufferParams& buffer_params)
{
/* block for buffer access */
thread_scoped_lock display_lock(display_mutex);
/* first check we already rendered something */
if(gpu_draw_ready) {
/* then verify the buffers have the expected size, so we don't
* draw previous results in a resized window */
if(!buffer_params.modified(display->params)) {
/* for CUDA we need to do tonemapping still, since we can
* only access GL buffers from the main thread */
if(gpu_need_tonemap) {
thread_scoped_lock buffers_lock(buffers_mutex);
tonemap();
gpu_need_tonemap = false;
gpu_need_tonemap_cond.notify_all();
}
display->draw(device);
if(display_outdated && (time_dt() - reset_time) > params.text_timeout)
return false;
return true;
}
}
return false;
}
void Session::run_gpu()
{
bool tiles_written = false;
start_time = time_dt();
reset_time = time_dt();
paused_time = 0.0;
last_update_time = time_dt();
if(!params.background)
progress.set_start_time(start_time + paused_time);
while(!progress.get_cancel()) {
/* advance to next tile */
bool no_tiles = !tile_manager.next();
if(params.background) {
/* if no work left and in background mode, we can stop immediately */
if(no_tiles) {
progress.set_status("Finished");
break;
}
}
else {
/* if in interactive mode, and we are either paused or done for now,
* wait for pause condition notify to wake up again */
thread_scoped_lock pause_lock(pause_mutex);
if(!pause && !tile_manager.done()) {
/* reset could have happened after no_tiles was set, before this lock.
* in this case we shall not wait for pause condition
*/
}
else if(pause || no_tiles) {
update_status_time(pause, no_tiles);
while(1) {
double pause_start = time_dt();
pause_cond.wait(pause_lock);
paused_time += time_dt() - pause_start;
if(!params.background)
progress.set_start_time(start_time + paused_time);
update_status_time(pause, no_tiles);
progress.set_update();
if(!pause)
break;
}
}
if(progress.get_cancel())
break;
}
if(!no_tiles) {
/* update scene */
update_scene();
if(device->error_message() != "")
progress.set_cancel(device->error_message());
if(progress.get_cancel())
break;
}
if(!no_tiles) {
/* buffers mutex is locked entirely while rendering each
* sample, and released/reacquired on each iteration to allow
* reset and draw in between */
thread_scoped_lock buffers_lock(buffers_mutex);
/* update status and timing */
update_status_time();
/* path trace */
path_trace();
device->task_wait();
if(device->error_message() != "")
progress.set_cancel(device->error_message());
/* update status and timing */
update_status_time();
gpu_need_tonemap = true;
gpu_draw_ready = true;
progress.set_update();
/* wait for tonemap */
if(!params.background) {
while(gpu_need_tonemap) {
if(progress.get_cancel())
break;
gpu_need_tonemap_cond.wait(buffers_lock);
}
}
if(device->error_message() != "")
progress.set_cancel(device->error_message());
tiles_written = update_progressive_refine(progress.get_cancel());
if(progress.get_cancel())
break;
}
}
if(!tiles_written)
update_progressive_refine(true);
}
/* CPU Session */
void Session::reset_cpu(BufferParams& buffer_params, int samples)
{
thread_scoped_lock reset_lock(delayed_reset.mutex);
thread_scoped_lock pause_lock(pause_mutex);
display_outdated = true;
reset_time = time_dt();
delayed_reset.params = buffer_params;
delayed_reset.samples = samples;
delayed_reset.do_reset = true;
device->task_cancel();
pause_cond.notify_all();
}
bool Session::draw_cpu(BufferParams& buffer_params)
{
thread_scoped_lock display_lock(display_mutex);
/* first check we already rendered something */
if(display->draw_ready()) {
/* then verify the buffers have the expected size, so we don't
* draw previous results in a resized window */
if(!buffer_params.modified(display->params)) {
display->draw(device);
if(display_outdated && (time_dt() - reset_time) > params.text_timeout)
return false;
return true;
}
}
return false;
}
bool Session::acquire_tile(Device *tile_device, RenderTile& rtile)
{
if(progress.get_cancel()) {
if(params.progressive_refine == false) {
/* for progressive refine current sample should be finished for all tiles */
return false;
}
}
thread_scoped_lock tile_lock(tile_mutex);
/* get next tile from manager */
Tile tile;
int device_num = device->device_number(tile_device);
if(!tile_manager.next_tile(tile, device_num))
return false;
/* fill render tile */
rtile.x = tile_manager.state.buffer.full_x + tile.x;
rtile.y = tile_manager.state.buffer.full_y + tile.y;
rtile.w = tile.w;
rtile.h = tile.h;
rtile.start_sample = tile_manager.state.sample;
rtile.num_samples = tile_manager.state.num_samples;
rtile.resolution = tile_manager.state.resolution_divider;
tile_lock.unlock();
/* in case of a permanent buffer, return it, otherwise we will allocate
* a new temporary buffer */
if(!params.background) {
tile_manager.state.buffer.get_offset_stride(rtile.offset, rtile.stride);
rtile.buffer = buffers->buffer.device_pointer;
rtile.rng_state = buffers->rng_state.device_pointer;
rtile.rgba = display->rgba.device_pointer;
rtile.buffers = buffers;
device->map_tile(tile_device, rtile);
return true;
}
/* fill buffer parameters */
BufferParams buffer_params = tile_manager.params;
buffer_params.full_x = rtile.x;
buffer_params.full_y = rtile.y;
buffer_params.width = rtile.w;
buffer_params.height = rtile.h;
buffer_params.get_offset_stride(rtile.offset, rtile.stride);
RenderBuffers *tilebuffers;
/* allocate buffers */
if(params.progressive_refine) {
tile_lock.lock();
if(tile_buffers.size() == 0)
tile_buffers.resize(tile_manager.state.num_tiles, NULL);
tilebuffers = tile_buffers[tile.index];
if(tilebuffers == NULL) {
tilebuffers = new RenderBuffers(tile_device);
tile_buffers[tile.index] = tilebuffers;
tilebuffers->reset(tile_device, buffer_params);
}
tile_lock.unlock();
}
else {
tilebuffers = new RenderBuffers(tile_device);
tilebuffers->reset(tile_device, buffer_params);
}
rtile.buffer = tilebuffers->buffer.device_pointer;
rtile.rng_state = tilebuffers->rng_state.device_pointer;
rtile.rgba = 0;
rtile.buffers = tilebuffers;
/* this will tag tile as IN PROGRESS in blender-side render pipeline,
* which is needed to highlight currently rendering tile before first
* sample was processed for it
*/
update_tile_sample(rtile);
return true;
}
void Session::update_tile_sample(RenderTile& rtile)
{
thread_scoped_lock tile_lock(tile_mutex);
if(update_render_tile_cb) {
if(params.progressive_refine == false) {
/* todo: optimize this by making it thread safe and removing lock */
update_render_tile_cb(rtile);
}
}
update_status_time();
}
void Session::release_tile(RenderTile& rtile)
{
thread_scoped_lock tile_lock(tile_mutex);
if(write_render_tile_cb) {
if(params.progressive_refine == false) {
/* todo: optimize this by making it thread safe and removing lock */
write_render_tile_cb(rtile);
delete rtile.buffers;
}
}
update_status_time();
}
void Session::run_cpu()
{
bool tiles_written = false;
last_update_time = time_dt();
{
/* reset once to start */
thread_scoped_lock reset_lock(delayed_reset.mutex);
thread_scoped_lock buffers_lock(buffers_mutex);
thread_scoped_lock display_lock(display_mutex);
reset_(delayed_reset.params, delayed_reset.samples);
delayed_reset.do_reset = false;
}
while(!progress.get_cancel()) {
/* advance to next tile */
bool no_tiles = !tile_manager.next();
bool need_tonemap = false;
if(params.background) {
/* if no work left and in background mode, we can stop immediately */
if(no_tiles) {
progress.set_status("Finished");
break;
}
}
else {
/* if in interactive mode, and we are either paused or done for now,
* wait for pause condition notify to wake up again */
thread_scoped_lock pause_lock(pause_mutex);
if(!pause && delayed_reset.do_reset) {
/* reset once to start */
thread_scoped_lock reset_lock(delayed_reset.mutex);
thread_scoped_lock buffers_lock(buffers_mutex);
thread_scoped_lock display_lock(display_mutex);
reset_(delayed_reset.params, delayed_reset.samples);
delayed_reset.do_reset = false;
}
else if(pause || no_tiles) {
update_status_time(pause, no_tiles);
while(1) {
double pause_start = time_dt();
pause_cond.wait(pause_lock);
paused_time += time_dt() - pause_start;
if(!params.background)
progress.set_start_time(start_time + paused_time);
update_status_time(pause, no_tiles);
progress.set_update();
if(!pause)
break;
}
}
if(progress.get_cancel())
break;
}
if(!no_tiles) {
/* buffers mutex is locked entirely while rendering each
* sample, and released/reacquired on each iteration to allow
* reset and draw in between */
thread_scoped_lock buffers_lock(buffers_mutex);
/* update scene */
update_scene();
if(device->error_message() != "")
progress.set_cancel(device->error_message());
if(progress.get_cancel())
break;
/* update status and timing */
update_status_time();
/* path trace */
path_trace();
/* update status and timing */
update_status_time();
if(!params.background)
need_tonemap = true;
if(device->error_message() != "")
progress.set_cancel(device->error_message());
}
device->task_wait();
{
thread_scoped_lock reset_lock(delayed_reset.mutex);
thread_scoped_lock buffers_lock(buffers_mutex);
thread_scoped_lock display_lock(display_mutex);
if(delayed_reset.do_reset) {
/* reset rendering if request from main thread */
delayed_reset.do_reset = false;
reset_(delayed_reset.params, delayed_reset.samples);
}
else if(need_tonemap) {
/* tonemap only if we do not reset, we don't we don't
* want to show the result of an incomplete sample*/
tonemap();
}
if(device->error_message() != "")
progress.set_cancel(device->error_message());
tiles_written = update_progressive_refine(progress.get_cancel());
}
progress.set_update();
}
if(!tiles_written)
update_progressive_refine(true);
}
void Session::run()
{
/* load kernels */
if(!kernels_loaded) {
progress.set_status("Loading render kernels (may take a few minutes the first time)");
if(!device->load_kernels(params.experimental)) {
string message = device->error_message();
if(message == "")
message = "Failed loading render kernel, see console for errors";
progress.set_status("Error", message);
progress.set_update();
return;
}
kernels_loaded = true;
}
/* session thread loop */
progress.set_status("Waiting for render to start");
/* run */
if(!progress.get_cancel()) {
/* reset number of rendered samples */
progress.reset_sample();
if(device_use_gl)
run_gpu();
else
run_cpu();
}
/* progress update */
if(progress.get_cancel())
progress.set_status("Cancel", progress.get_cancel_message());
else
progress.set_update();
}
bool Session::draw(BufferParams& buffer_params)
{
if(device_use_gl)
return draw_gpu(buffer_params);
else
return draw_cpu(buffer_params);
}
void Session::reset_(BufferParams& buffer_params, int samples)
{
if(buffers) {
if(buffer_params.modified(buffers->params)) {
gpu_draw_ready = false;
buffers->reset(device, buffer_params);
display->reset(device, buffer_params);
}
}
tile_manager.reset(buffer_params, samples);
start_time = time_dt();
preview_time = 0.0;
paused_time = 0.0;
if(!params.background)
progress.set_start_time(start_time + paused_time);
}
void Session::reset(BufferParams& buffer_params, int samples)
{
if(device_use_gl)
reset_gpu(buffer_params, samples);
else
reset_cpu(buffer_params, samples);
if(params.progressive_refine) {
thread_scoped_lock buffers_lock(buffers_mutex);
foreach(RenderBuffers *buffers, tile_buffers)
delete buffers;
tile_buffers.clear();
}
}
void Session::set_samples(int samples)
{
if(samples != params.samples) {
params.samples = samples;
tile_manager.set_samples(samples);
{
thread_scoped_lock pause_lock(pause_mutex);
}
pause_cond.notify_all();
}
}
void Session::set_pause(bool pause_)
{
bool notify = false;
{
thread_scoped_lock pause_lock(pause_mutex);
if(pause != pause_) {
pause = pause_;
notify = true;
}
}
if(notify)
pause_cond.notify_all();
}
void Session::wait()
{
session_thread->join();
delete session_thread;
session_thread = NULL;
}
void Session::update_scene()
{
thread_scoped_lock scene_lock(scene->mutex);
/* update camera if dimensions changed for progressive render. the camera
* knows nothing about progressive or cropped rendering, it just gets the
* image dimensions passed in */
Camera *cam = scene->camera;
int width = tile_manager.state.buffer.full_width;
int height = tile_manager.state.buffer.full_height;
int resolution = tile_manager.state.resolution_divider;
if(width != cam->width || height != cam->height) {
cam->width = width;
cam->height = height;
cam->resolution = resolution;
cam->tag_update();
}
/* number of samples is needed by multi jittered sampling pattern */
Integrator *integrator = scene->integrator;
if(integrator->sampling_pattern == SAMPLING_PATTERN_CMJ) {
int aa_samples = tile_manager.num_samples;
if(aa_samples != integrator->aa_samples) {
integrator->aa_samples = aa_samples;
integrator->tag_update(scene);
}
}
/* update scene */
if(scene->need_update()) {
progress.set_status("Updating Scene");
scene->device_update(device, progress);
}
}
void Session::update_status_time(bool show_pause, bool show_done)
{
int sample = tile_manager.state.sample;
int resolution = tile_manager.state.resolution_divider;
int num_tiles = tile_manager.state.num_tiles;
int tile = tile_manager.state.num_rendered_tiles;
/* update status */
string status, substatus;
if(!params.progressive) {
bool is_gpu = params.device.type == DEVICE_CUDA || params.device.type == DEVICE_OPENCL;
bool is_multidevice = params.device.multi_devices.size() > 1;
bool is_cpu = params.device.type == DEVICE_CPU;
substatus = string_printf("Path Tracing Tile %d/%d", tile, num_tiles);
if((is_gpu && !is_multidevice) || (is_cpu && num_tiles == 1)) {
/* when rendering on GPU multithreading happens within single tile, as in
* tiles are handling sequentially and in this case we could display
* currently rendering sample number
* this helps a lot from feedback point of view.
* also display the info on CPU, when using 1 tile only
*/
int sample = progress.get_sample(), num_samples = tile_manager.num_samples;
if(tile > 1) {
/* sample counter is global for all tiles, subtract samples
* from already finished tiles to get sample counter for
* current tile only
*/
sample -= (tile - 1) * num_samples;
}
substatus += string_printf(", Sample %d/%d", sample, num_samples);
}
}
else if(tile_manager.num_samples == INT_MAX)
substatus = string_printf("Path Tracing Sample %d", sample+1);
else
substatus = string_printf("Path Tracing Sample %d/%d", sample+1, tile_manager.num_samples);
if(show_pause)
status = "Paused";
else if(show_done)
status = "Done";
else
status = "Rendering";
progress.set_status(status, substatus);
/* update timing */
if(preview_time == 0.0 && resolution == 1)
preview_time = time_dt();
double tile_time = (tile == 0 || sample == 0)? 0.0: (time_dt() - preview_time - paused_time) / sample;
/* negative can happen when we pause a bit before rendering, can discard that */
if(preview_time < 0.0) preview_time = 0.0;
progress.set_tile(tile, tile_time);
}
void Session::update_progress_sample()
{
progress.increment_sample();
}
void Session::path_trace()
{
/* add path trace task */
DeviceTask task(DeviceTask::PATH_TRACE);
task.acquire_tile = function_bind(&Session::acquire_tile, this, _1, _2);
task.release_tile = function_bind(&Session::release_tile, this, _1);
task.get_cancel = function_bind(&Progress::get_cancel, &this->progress);
task.update_tile_sample = function_bind(&Session::update_tile_sample, this, _1);
task.update_progress_sample = function_bind(&Session::update_progress_sample, this);
task.need_finish_queue = params.progressive_refine;
device->task_add(task);
}
void Session::tonemap()
{
/* add tonemap task */
DeviceTask task(DeviceTask::TONEMAP);
task.x = tile_manager.state.buffer.full_x;
task.y = tile_manager.state.buffer.full_y;
task.w = tile_manager.state.buffer.width;
task.h = tile_manager.state.buffer.height;
task.rgba = display->rgba.device_pointer;
task.buffer = buffers->buffer.device_pointer;
task.sample = tile_manager.state.sample;
tile_manager.state.buffer.get_offset_stride(task.offset, task.stride);
if(task.w > 0 && task.h > 0) {
device->task_add(task);
device->task_wait();
/* set display to new size */
display->draw_set(task.w, task.h);
}
display_outdated = false;
}
bool Session::update_progressive_refine(bool cancel)
{
int sample = tile_manager.state.sample + 1;
bool write = sample == tile_manager.num_samples || cancel;
double current_time = time_dt();
if (current_time - last_update_time < 1.0) {
/* if last sample was processed, we need to write buffers anyway */
if (!write)
return false;
}
if(params.progressive_refine) {
foreach(RenderBuffers *buffers, tile_buffers) {
RenderTile rtile;
rtile.buffers = buffers;
rtile.sample = sample;
if(write)
write_render_tile_cb(rtile);
else
update_render_tile_cb(rtile);
}
}
last_update_time = current_time;
return write;
}
void Session::device_free()
{
scene->device_free();
foreach(RenderBuffers *buffers, tile_buffers)
delete buffers;
tile_buffers.clear();
/* used from background render only, so no need to
* re-create render/display buffers here
*/
}
CCL_NAMESPACE_END