Method _process_picking

scene/main/viewport.cpp:736–1037

#if !defined(PHYSICS_2D_DISABLED) || !defined(PHYSICS_3D_DISABLED)
void Viewport::_process_picking() {
	if (!is_inside_tree()) {
		return;
	}
	if (!physics_object_picking) {
		return;
	}
	if (Object::cast_to<Window>(this) && Input::get_singleton()->get_mouse_mode() == Input::MOUSE_MODE_CAPTURED) {
		return;
	}
	if (!gui.mouse_in_viewport || gui.subwindow_over) {
		// Clear picking events if the mouse has left the viewport or is over an embedded window.
		// These are locations, that are expected to not trigger physics picking.
		physics_picking_events.clear();
		return;
	}
#ifndef XR_DISABLED
	if (use_xr) {
		if (XRServer::get_singleton() != nullptr) {
			Ref<XRInterface> xr_interface = XRServer::get_singleton()->get_primary_interface();
			if (xr_interface.is_valid() && xr_interface->is_initialized() && xr_interface->get_view_count() > 1) {
				WARN_PRINT_ONCE("Object picking can't be used when stereo rendering, this will be turned off!");
				physics_object_picking = false; // don't try again.
				return;
			}
		}
	}
#endif // XR_DISABLED

	_drop_physics_mouseover(true);

#ifndef PHYSICS_3D_DISABLED
	Vector2 last_pos(1e20, 1e20);
	CollisionObject3D *last_object = nullptr;
	ObjectID last_id;
	PhysicsDirectSpaceState3D::RayResult result;
#endif // PHYSICS_3D_DISABLED

#ifndef PHYSICS_2D_DISABLED
	PhysicsDirectSpaceState2D *ss2d = PhysicsServer2D::get_singleton()->space_get_direct_state(find_world_2d()->get_space());
#endif // PHYSICS_2D_DISABLED

	SubViewportContainer *parent_svc = Object::cast_to<SubViewportContainer>(get_parent());
	bool parent_ignore_mouse = (parent_svc && parent_svc->get_mouse_filter_with_override() == Control::MOUSE_FILTER_IGNORE);
	bool create_passive_hover_event = true;
	if (gui.mouse_over || parent_ignore_mouse) {
		// When the mouse is over a Control node, passive hovering would cause input events for Colliders, that are behind Control nodes.
		// When parent SubViewportContainer ignores mouse, that setting should be respected.
		create_passive_hover_event = false;
	} else {
		for (const Ref<InputEvent> &e : physics_picking_events) {
			Ref<InputEventMouse> m = e;
			if (m.is_valid()) {
				// A mouse event exists, so passive hovering isn't necessary.
				create_passive_hover_event = false;
				break;
			}
		}