Make Servers truly Thread Safe

-Rendering server now uses a split RID allocate/initialize internally, this allows generating RIDs immediately but initialization to happen later on the proper thread (as rendering APIs generally requiere to call on the right thread).
-RenderingServerWrapMT is no more, multithreading is done in RenderingServerDefault.
-Some functions like texture or mesh creation, when renderer supports it, can register and return immediately (so no waiting for server API to flush, and saving staging and command buffer memory).
-3D physics server changed to be made multithread friendly.
-Added PhysicsServer3DWrapMT to use 3D physics server from multiple threads.
-Disablet Bullet (too much effort to make multithread friendly, this needs to be fixed eventually).

1 files changed, 0 insertions, 174 deletions

diff --git a/servers/rendering/rendering_server_wrap_mt.cpp b/servers/rendering/rendering_server_wrap_mt.cpp
deleted file mode 100644
index 9b8d35e5b3..0000000000
--- a/servers/rendering/rendering_server_wrap_mt.cpp
+++ /dev/null
@@ -1,174 +0,0 @@
-/*************************************************************************/
-/*  rendering_server_wrap_mt.cpp                                         */
-/*************************************************************************/
-/*                       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.                */
-/*************************************************************************/
-
-#include "rendering_server_wrap_mt.h"
-#include "core/config/project_settings.h"
-#include "core/os/os.h"
-#include "servers/display_server.h"
-
-void RenderingServerWrapMT::thread_exit() {
-	exit = true;
-}
-
-void RenderingServerWrapMT::thread_draw(bool p_swap_buffers, double frame_step) {
-	if (!atomic_decrement(&draw_pending)) {
-		rendering_server->draw(p_swap_buffers, frame_step);
-	}
-}
-
-void RenderingServerWrapMT::thread_flush() {
-	atomic_decrement(&draw_pending);
-}
-
-void RenderingServerWrapMT::_thread_callback(void *_instance) {
-	RenderingServerWrapMT *vsmt = reinterpret_cast<RenderingServerWrapMT *>(_instance);
-
-	vsmt->thread_loop();
-}
-
-void RenderingServerWrapMT::thread_loop() {
-	server_thread = Thread::get_caller_id();
-
-	DisplayServer::get_singleton()->make_rendering_thread();
-
-	rendering_server->init();
-
-	exit = false;
-	draw_thread_up = true;
-	while (!exit) {
-		// flush commands one by one, until exit is requested
-		command_queue.wait_and_flush_one();
-	}
-
-	command_queue.flush_all(); // flush all
-
-	rendering_server->finish();
-}
-
-/* EVENT QUEUING */
-
-void RenderingServerWrapMT::sync() {
-	if (create_thread) {
-		atomic_increment(&draw_pending);
-		command_queue.push_and_sync(this, &RenderingServerWrapMT::thread_flush);
-	} else {
-		command_queue.flush_all(); //flush all pending from other threads
-	}
-}
-
-void RenderingServerWrapMT::draw(bool p_swap_buffers, double frame_step) {
-	if (create_thread) {
-		atomic_increment(&draw_pending);
-		command_queue.push(this, &RenderingServerWrapMT::thread_draw, p_swap_buffers, frame_step);
-	} else {
-		rendering_server->draw(p_swap_buffers, frame_step);
-	}
-}
-
-void RenderingServerWrapMT::init() {
-	if (create_thread) {
-		print_verbose("RenderingServerWrapMT: Creating render thread");
-		DisplayServer::get_singleton()->release_rendering_thread();
-		if (create_thread) {
-			thread.start(_thread_callback, this);
-			print_verbose("RenderingServerWrapMT: Starting render thread");
-		}
-		while (!draw_thread_up) {
-			OS::get_singleton()->delay_usec(1000);
-		}
-		print_verbose("RenderingServerWrapMT: Finished render thread");
-	} else {
-		rendering_server->init();
-	}
-}
-
-void RenderingServerWrapMT::finish() {
-	sky_free_cached_ids();
-	shader_free_cached_ids();
-	material_free_cached_ids();
-	mesh_free_cached_ids();
-	multimesh_free_cached_ids();
-	immediate_free_cached_ids();
-	skeleton_free_cached_ids();
-	directional_light_free_cached_ids();
-	omni_light_free_cached_ids();
-	spot_light_free_cached_ids();
-	reflection_probe_free_cached_ids();
-	gi_probe_free_cached_ids();
-	lightmap_free_cached_ids();
-	particles_free_cached_ids();
-	particles_collision_free_cached_ids();
-	camera_free_cached_ids();
-	viewport_free_cached_ids();
-	environment_free_cached_ids();
-	camera_effects_free_cached_ids();
-	scenario_free_cached_ids();
-	instance_free_cached_ids();
-	canvas_free_cached_ids();
-	canvas_item_free_cached_ids();
-	canvas_light_occluder_free_cached_ids();
-	canvas_occluder_polygon_free_cached_ids();
-
-	if (create_thread) {
-		command_queue.push(this, &RenderingServerWrapMT::thread_exit);
-		thread.wait_to_finish();
-	} else {
-		rendering_server->finish();
-	}
-}
-
-void RenderingServerWrapMT::set_use_vsync_callback(bool p_enable) {
-	singleton_mt->call_set_use_vsync(p_enable);
-}
-
-RenderingServerWrapMT *RenderingServerWrapMT::singleton_mt = nullptr;
-
-RenderingServerWrapMT::RenderingServerWrapMT(RenderingServer *p_contained, bool p_create_thread) :
-		command_queue(p_create_thread) {
-	singleton_mt = this;
-	DisplayServer::switch_vsync_function = set_use_vsync_callback; //as this goes to another thread, make sure it goes properly
-
-	rendering_server = p_contained;
-	create_thread = p_create_thread;
-	draw_pending = 0;
-	draw_thread_up = false;
-	pool_max_size = GLOBAL_GET("memory/limits/multithreaded_server/rid_pool_prealloc");
-
-	if (!p_create_thread) {
-		server_thread = Thread::get_caller_id();
-	} else {
-		server_thread = 0;
-	}
-}
-
-RenderingServerWrapMT::~RenderingServerWrapMT() {
-	memdelete(rendering_server);
-	//finish();
-}