godot/core/os/threaded_array_processor.h
Hugo Locurcio 0e943939e2
Add an editor setting to configure number of threads for lightmap baking
This can be used to free some CPU cores when baking lightmaps.
When using fewer CPU cores, lightmap baking is slower but background
tasks aren't slowed down as much.
2021-10-05 17:35:20 +02:00

117 lines
4.3 KiB
C++

/*************************************************************************/
/* threaded_array_processor.h */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/*************************************************************************/
#ifndef THREADED_ARRAY_PROCESSOR_H
#define THREADED_ARRAY_PROCESSOR_H
#include "core/os/mutex.h"
#include "core/os/os.h"
#include "core/os/thread.h"
#include "core/os/thread_safe.h"
#include "core/safe_refcount.h"
template <class C, class U>
struct ThreadArrayProcessData {
uint32_t elements;
SafeNumeric<uint32_t> index;
C *instance;
U userdata;
void (C::*method)(uint32_t, U);
void process(uint32_t p_index) {
(instance->*method)(p_index, userdata);
}
};
#ifndef NO_THREADS
template <class T>
void process_array_thread(void *ud) {
T &data = *(T *)ud;
while (true) {
uint32_t index = data.index.increment();
if (index >= data.elements) {
break;
}
data.process(index);
}
}
// p_num_threads is the number of logical CPU cores to use (0 = use all logical CPU cores available).
// Negative values subtract from the total number of logical CPU cores available.
template <class C, class M, class U>
void thread_process_array(uint32_t p_elements, C *p_instance, M p_method, U p_userdata, int p_num_threads = 0) {
ThreadArrayProcessData<C, U> data;
data.method = p_method;
data.instance = p_instance;
data.userdata = p_userdata;
data.index.set(0);
data.elements = p_elements;
data.process(0); //process first, let threads increment for next
int thread_count;
if (p_num_threads <= 0) {
thread_count = MAX(1, OS::get_singleton()->get_processor_count() + p_num_threads);
} else {
thread_count = p_num_threads;
}
Thread *threads = memnew_arr(Thread, thread_count);
for (int i = 0; i < thread_count; i++) {
threads[i].start(process_array_thread<ThreadArrayProcessData<C, U>>, &data);
}
for (int i = 0; i < thread_count; i++) {
threads[i].wait_to_finish();
}
memdelete_arr(threads);
}
#else
// p_num_threads is intentionally unused when threads are disabled.
template <class C, class M, class U>
void thread_process_array(uint32_t p_elements, C *p_instance, M p_method, U p_userdata, int p_num_threads = 0) {
ThreadArrayProcessData<C, U> data;
data.method = p_method;
data.instance = p_instance;
data.userdata = p_userdata;
data.index.set(0);
data.elements = p_elements;
for (uint32_t i = 0; i < p_elements; i++) {
data.process(i);
}
}
#endif
#endif // THREADED_ARRAY_PROCESSOR_H