Prepare NavigationServer for process() and physics_process() split

Prepares the NavigationServer API for a split of its functionality between frame process() and stepped physics_process().

Author: smix8

main/main.cpp

@@ -4648,10 +4648,10 @@ bool Main::iteration() {
 		uint64_t navigation_begin = OS::get_singleton()->get_ticks_usec();
 
 #ifndef NAVIGATION_2D_DISABLED
-		NavigationServer2D::get_singleton()->process(physics_step * time_scale);
+		NavigationServer2D::get_singleton()->physics_process(physics_step * time_scale);
 #endif // NAVIGATION_2D_DISABLED
 #ifndef NAVIGATION_3D_DISABLED
-		NavigationServer3D::get_singleton()->process(physics_step * time_scale);
+		NavigationServer3D::get_singleton()->physics_process(physics_step * time_scale);
 #endif // NAVIGATION_3D_DISABLED
 
 		navigation_process_ticks = MAX(navigation_process_ticks, OS::get_singleton()->get_ticks_usec() - navigation_begin); // keep the largest one for reference
@@ -4691,6 +4691,13 @@ bool Main::iteration() {
 	}
 	message_queue->flush();
 
+#ifndef NAVIGATION_2D_DISABLED
+	NavigationServer2D::get_singleton()->process(process_step * time_scale);
+#endif // NAVIGATION_2D_DISABLED
+#ifndef NAVIGATION_3D_DISABLED
+	NavigationServer3D::get_singleton()->process(process_step * time_scale);
+#endif // NAVIGATION_3D_DISABLED
+
 	RenderingServer::get_singleton()->sync(); //sync if still drawing from previous frames.
 
 	const bool has_pending_resources_for_processing = RD::get_singleton() && RD::get_singleton()->has_pending_resources_for_processing();

modules/navigation_2d/2d/godot_navigation_server_2d.cpp

@@ -1138,8 +1138,6 @@ Vector<Vector2> GodotNavigationServer2D::obstacle_get_vertices(RID p_obstacle) c
 }
 
 void GodotNavigationServer2D::flush_queries() {
-	// In c++ we can't be sure that this is performed in the main thread
-	// even with mutable functions.
 	MutexLock lock(commands_mutex);
 	MutexLock lock2(operations_mutex);
 
@@ -1259,7 +1257,21 @@ void GodotNavigationServer2D::internal_free_obstacle(RID p_object) {
 	}
 }
 
-void GodotNavigationServer2D::process(real_t p_delta_time) {
+void GodotNavigationServer2D::process(double p_delta_time) {
+	// Called for each main loop iteration AFTER node and user script process() and BEFORE RenderingServer sync.
+	// Will run reliably every rendered frame independent of the physics tick rate.
+	// Use for things that (only) need to update once per main loop iteration and rendered frame or is visible to the user.
+	// E.g. (final) sync of objects for this main loop iteration, updating rendered debug visuals, updating debug statistics, ...
+}
+
+void GodotNavigationServer2D::physics_process(double p_delta_time) {
+	// Called for each physics process step AFTER node and user script physics_process() and BEFORE PhysicsServer sync.
+	// Will NOT run reliably every rendered frame. If there is no physics step this function will not run.
+	// Use for physics or step depending calculations and updates where the result affects the next step calculation.
+	// E.g. anything physics sync related, avoidance simulations, physics space state queries, ...
+	// If physics process needs to play catchup this function will be called multiple times per frame so it should not hold
+	// costly updates that are not important outside the stepped calculations to avoid causing a physics performance death spiral.
+
 	flush_queries();
 
 	if (!active) {

modules/navigation_2d/2d/godot_navigation_server_2d.h

@@ -320,7 +320,9 @@ class GodotNavigationServer2D : public NavigationServer2D {
 	virtual void set_active(bool p_active) override;
 
 	void flush_queries();
-	virtual void process(real_t p_delta_time) override;
+
+	virtual void process(double p_delta_time) override;
+	virtual void physics_process(double p_delta_time) override;
 	virtual void init() override;
 	virtual void sync() override;
 	virtual void finish() override;

modules/navigation_2d/nav_map_2d.cpp

@@ -532,10 +532,8 @@ void NavMap2D::compute_single_avoidance_step(uint32_t p_index, NavAgent2D **p_ag
 	(*(p_agent + p_index))->update();
 }
 
-void NavMap2D::step(real_t p_deltatime) {
-	deltatime = p_deltatime;
-
-	rvo_simulation.setTimeStep(float(deltatime));
+void NavMap2D::step(double p_delta_time) {
+	rvo_simulation.setTimeStep(float(p_delta_time));
 
 	if (active_avoidance_agents.size() > 0) {
 		if (use_threads && avoidance_use_multiple_threads) {

modules/navigation_2d/nav_map_2d.h

@@ -91,9 +91,6 @@ class NavMap2D : public NavRid2D {
 	/// Are rvo obstacles modified?
 	bool obstacles_dirty = true;
 
-	/// Physics delta time.
-	real_t deltatime = 0.0;
-
 	/// Change the id each time the map is updated.
 	uint32_t iteration_id = 0;
 
@@ -203,7 +200,7 @@ class NavMap2D : public NavRid2D {
 	Vector2 get_random_point(uint32_t p_navigation_layers, bool p_uniformly) const;
 
 	void sync();
-	void step(real_t p_deltatime);
+	void step(double p_delta_time);
 	void dispatch_callbacks();
 
 	// Performance Monitor

modules/navigation_3d/3d/godot_navigation_server_3d.cpp

@@ -1306,8 +1306,6 @@ void GodotNavigationServer3D::set_active(bool p_active) {
 }
 
 void GodotNavigationServer3D::flush_queries() {
-	// In c++ we can't be sure that this is performed in the main thread
-	// even with mutable functions.
 	MutexLock lock(commands_mutex);
 	MutexLock lock2(operations_mutex);
 
@@ -1340,7 +1338,21 @@ void GodotNavigationServer3D::sync() {
 	}
 }
 
-void GodotNavigationServer3D::process(real_t p_delta_time) {
+void GodotNavigationServer3D::process(double p_delta_time) {
+	// Called for each main loop iteration AFTER node and user script process() and BEFORE RenderingServer sync.
+	// Will run reliably every rendered frame independent of the physics tick rate.
+	// Use for things that (only) need to update once per main loop iteration and rendered frame or is visible to the user.
+	// E.g. (final) sync of objects for this main loop iteration, updating rendered debug visuals, updating debug statistics, ...
+}
+
+void GodotNavigationServer3D::physics_process(double p_delta_time) {
+	// Called for each physics process step AFTER node and user script physics_process() and BEFORE PhysicsServer sync.
+	// Will NOT run reliably every rendered frame. If there is no physics step this function will not run.
+	// Use for physics or step depending calculations and updates where the result affects the next step calculation.
+	// E.g. anything physics sync related, avoidance simulations, physics space state queries, ...
+	// If physics process needs to play catchup this function will be called multiple times per frame so it should not hold
+	// costly updates that are not important outside the stepped calculations to avoid causing a physics performance death spiral.
+
 	flush_queries();
 
 	if (!active) {

modules/navigation_3d/3d/godot_navigation_server_3d.h

@@ -280,7 +280,9 @@ class GodotNavigationServer3D : public NavigationServer3D {
 	virtual void set_active(bool p_active) override;
 
 	void flush_queries();
-	virtual void process(real_t p_delta_time) override;
+
+	virtual void process(double p_delta_time) override;
+	virtual void physics_process(double p_delta_time) override;
 	virtual void init() override;
 	virtual void sync() override;
 	virtual void finish() override;

modules/navigation_3d/nav_map_3d.cpp

@@ -614,11 +614,9 @@ void NavMap3D::compute_single_avoidance_step_3d(uint32_t index, NavAgent3D **age
 	(*(agent + index))->update();
 }
 
-void NavMap3D::step(real_t p_deltatime) {
-	deltatime = p_deltatime;
-
-	rvo_simulation_2d.setTimeStep(float(deltatime));
-	rvo_simulation_3d.setTimeStep(float(deltatime));
+void NavMap3D::step(double p_delta_time) {
+	rvo_simulation_2d.setTimeStep(float(p_delta_time));
+	rvo_simulation_3d.setTimeStep(float(p_delta_time));
 
 	if (active_2d_avoidance_agents.size() > 0) {
 		if (use_threads && avoidance_use_multiple_threads) {

modules/navigation_3d/nav_map_3d.h

@@ -99,9 +99,6 @@ class NavMap3D : public NavRid3D {
 	/// Are rvo obstacles modified?
 	bool obstacles_dirty = true;
 
-	/// Physics delta time
-	real_t deltatime = 0.0;
-
 	/// Change the id each time the map is updated.
 	uint32_t iteration_id = 0;
 
@@ -221,7 +218,7 @@ class NavMap3D : public NavRid3D {
 	Vector3 get_random_point(uint32_t p_navigation_layers, bool p_uniformly) const;
 
 	void sync();
-	void step(real_t p_deltatime);
+	void step(double p_delta_time);
 	void dispatch_callbacks();
 
 	// Performance Monitor

servers/navigation_server_2d.h

@@ -308,7 +308,8 @@ class NavigationServer2D : public Object {
 	/// The result of this process is needed by the physics server,
 	/// so this must be called in the main thread.
 	/// Note: This function is not thread safe.
-	virtual void process(real_t delta_time) = 0;
+	virtual void process(double p_delta_time) = 0;
+	virtual void physics_process(double p_delta_time) = 0;
 	virtual void init() = 0;
 	virtual void sync() = 0;
 	virtual void finish() = 0;