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, 23 insertions, 11 deletions

diff --git a/servers/rendering/renderer_canvas_cull.h b/servers/rendering/renderer_canvas_cull.h
index 7496a413ee..b71f8e5a9a 100644
--- a/servers/rendering/renderer_canvas_cull.h
+++ b/servers/rendering/renderer_canvas_cull.h
@@ -101,9 +101,9 @@ public:
 		}
 	};
 
-	RID_PtrOwner<LightOccluderPolygon> canvas_light_occluder_polygon_owner;
+	RID_PtrOwner<LightOccluderPolygon, true> canvas_light_occluder_polygon_owner;
 
-	RID_PtrOwner<RendererCanvasRender::LightOccluderInstance> canvas_light_occluder_owner;
+	RID_PtrOwner<RendererCanvasRender::LightOccluderInstance, true> canvas_light_occluder_owner;
 
 	struct Canvas : public RendererViewport::CanvasBase {
 		Set<RID> viewports;
@@ -148,9 +148,9 @@ public:
 		}
 	};
 
-	mutable RID_PtrOwner<Canvas> canvas_owner;
-	RID_PtrOwner<Item> canvas_item_owner;
-	RID_PtrOwner<RendererCanvasRender::Light> canvas_light_owner;
+	mutable RID_PtrOwner<Canvas, true> canvas_owner;
+	RID_PtrOwner<Item, true> canvas_item_owner;
+	RID_PtrOwner<RendererCanvasRender::Light, true> canvas_light_owner;
 
 	bool disable_scale;
 	bool sdf_used = false;
@@ -168,13 +168,17 @@ public:
 
 	bool was_sdf_used();
 
-	RID canvas_create();
+	RID canvas_allocate();
+	void canvas_initialize(RID p_rid);
+
 	void canvas_set_item_mirroring(RID p_canvas, RID p_item, const Point2 &p_mirroring);
 	void canvas_set_modulate(RID p_canvas, const Color &p_color);
 	void canvas_set_parent(RID p_canvas, RID p_parent, float p_scale);
 	void canvas_set_disable_scale(bool p_disable);
 
-	RID canvas_item_create();
+	RID canvas_item_allocate();
+	void canvas_item_initialize(RID p_rid);
+
 	void canvas_item_set_parent(RID p_item, RID p_parent);
 
 	void canvas_item_set_visible(RID p_item, bool p_visible);
@@ -222,7 +226,9 @@ public:
 
 	void canvas_item_set_canvas_group_mode(RID p_item, RS::CanvasGroupMode p_mode, float p_clear_margin = 5.0, bool p_fit_empty = false, float p_fit_margin = 0.0, bool p_blur_mipmaps = false);
 
-	RID canvas_light_create();
+	RID canvas_light_allocate();
+	void canvas_light_initialize(RID p_rid);
+
 	void canvas_light_set_mode(RID p_light, RS::CanvasLightMode p_mode);
 	void canvas_light_attach_to_canvas(RID p_light, RID p_canvas);
 	void canvas_light_set_enabled(RID p_light, bool p_enabled);
@@ -246,7 +252,9 @@ public:
 	void canvas_light_set_shadow_color(RID p_light, const Color &p_color);
 	void canvas_light_set_shadow_smooth(RID p_light, float p_smooth);
 
-	RID canvas_light_occluder_create();
+	RID canvas_light_occluder_allocate();
+	void canvas_light_occluder_initialize(RID p_rid);
+
 	void canvas_light_occluder_attach_to_canvas(RID p_occluder, RID p_canvas);
 	void canvas_light_occluder_set_enabled(RID p_occluder, bool p_enabled);
 	void canvas_light_occluder_set_polygon(RID p_occluder, RID p_polygon);
@@ -254,14 +262,18 @@ public:
 	void canvas_light_occluder_set_transform(RID p_occluder, const Transform2D &p_xform);
 	void canvas_light_occluder_set_light_mask(RID p_occluder, int p_mask);
 
-	RID canvas_occluder_polygon_create();
+	RID canvas_occluder_polygon_allocate();
+	void canvas_occluder_polygon_initialize(RID p_rid);
+
 	void canvas_occluder_polygon_set_shape(RID p_occluder_polygon, const Vector<Vector2> &p_shape, bool p_closed);
 
 	void canvas_occluder_polygon_set_cull_mode(RID p_occluder_polygon, RS::CanvasOccluderPolygonCullMode p_mode);
 
 	void canvas_set_shadow_texture_size(int p_size);
 
-	RID canvas_texture_create();
+	RID canvas_texture_allocate();
+	void canvas_texture_initialize(RID p_rid);
+
 	void canvas_texture_set_channel(RID p_canvas_texture, RS::CanvasTextureChannel p_channel, RID p_texture);
 	void canvas_texture_set_shading_parameters(RID p_canvas_texture, const Color &p_base_color, float p_shininess);