Discrete Level of Detail

Add scene side discrete level of detail.

New node `LOD` for UI, and `LODManager` within `World` for automatically updating child visibilities based on distance from cameras.

doc/classes/Camera.xml

@@ -137,6 +137,11 @@
 		</method>
 	</methods>
 	<members>
+		<member name="affect_lod" type="bool" setter="set_affect_lod" getter="get_affect_lod" default="true">
+			If [code]true[/code], the camera will be used to calculate the level of detail in [LOD] nodes.
+			Objects further from the camera will select lower levels of detail than those closer to the camera.
+			[b]Note:[/b] This property has no effect if [member projection] is set to [constant PROJECTION_ORTHOGONAL].
+		</member>
 		<member name="cull_mask" type="int" setter="set_cull_mask" getter="get_cull_mask" default="1048575">
 			The culling mask that describes which 3D render layers are rendered by this camera.
 		</member>

doc/classes/GeometryInstance.xml

@@ -45,22 +45,6 @@
 		<member name="lightmap_scale" type="int" setter="set_lightmap_scale" getter="get_lightmap_scale" enum="GeometryInstance.LightmapScale" default="0">
 			Scale factor for the generated baked lightmap. Useful for adding detail to certain mesh instances.
 		</member>
-		<member name="lod_max_distance" type="float" setter="set_lod_max_distance" getter="get_lod_max_distance" default="0.0">
-			The GeometryInstance's max LOD distance.
-			[b]Note:[/b] This property currently has no effect.
-		</member>
-		<member name="lod_max_hysteresis" type="float" setter="set_lod_max_hysteresis" getter="get_lod_max_hysteresis" default="0.0">
-			The GeometryInstance's max LOD margin.
-			[b]Note:[/b] This property currently has no effect.
-		</member>
-		<member name="lod_min_distance" type="float" setter="set_lod_min_distance" getter="get_lod_min_distance" default="0.0">
-			The GeometryInstance's min LOD distance.
-			[b]Note:[/b] This property currently has no effect.
-		</member>
-		<member name="lod_min_hysteresis" type="float" setter="set_lod_min_hysteresis" getter="get_lod_min_hysteresis" default="0.0">
-			The GeometryInstance's min LOD margin.
-			[b]Note:[/b] This property currently has no effect.
-		</member>
 		<member name="material_overlay" type="Material" setter="set_material_overlay" getter="get_material_overlay">
 			The material overlay for the whole geometry.
 			If a material is assigned to this property, it will be rendered on top of any other active material for all the surfaces.

doc/classes/LOD.xml

@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<class name="LOD" inherits="Spatial" version="3.6" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../class.xsd">
+	<brief_description>
+		Provides discrete level of detail.
+	</brief_description>
+	<description>
+		Automatically hides and shows [Spatial] children depending on the distance from the closest [Camera] to the [LOD] node. Child nodes that don't inherit from [Spatial] are ignored by the LOD system.
+		Children are shown in order with the first children shown when closest to the [Camera], and the latter children shown when further away.
+		The threshold distances for changes are determined by [member Spatial.lod_range].
+		For example, a first child with a range of [code]2[/code] will be shown from distance 0 to 2. A second child with a range of [code]5[/code] will be shown from distance 2 to 7, etc.
+	</description>
+	<tutorials>
+	</tutorials>
+	<methods>
+	</methods>
+	<members>
+		<member name="hysteresis" type="float" setter="set_hysteresis" getter="get_hysteresis" default="1.0">
+			To prevent flickering at borders, a hysteresis distance will be added to threshold distances when the object is moving away from the [Camera].
+		</member>
+		<member name="lod_priority" type="int" setter="set_lod_priority" getter="get_lod_priority" default="0">
+			Determines the rate at which level of detail will be updated.
+			Higher priorities will update faster, but use more CPU.
+		</member>
+	</members>
+	<constants>
+	</constants>
+</class>

doc/classes/Spatial.xml

@@ -266,6 +266,10 @@
 		<member name="global_translation" type="Vector3" setter="set_global_translation" getter="get_global_translation">
 			Global position of this node. This is equivalent to [code]global_transform.origin[/code].
 		</member>
+		<member name="lod_range" type="float" setter="set_lod_range" getter="get_lod_range" default="10.0">
+			Determines the threshold distance at which this node will be shown or hidden when this node is parented by a [LOD] node.
+			For example, a first child with a range of [code]2[/code] will be shown from distance 0 to 2. A second child with a range of [code]5[/code] will be shown from distance 2 to 7, etc.
+		</member>
 		<member name="merging_mode" type="int" setter="set_merging_mode" getter="get_merging_mode" enum="Spatial.MergingMode" default="0">
 			The merging mode determines whether merging features of the engine ([MergeGroup] and [RoomManager]) will attempt to operate on branches of the scene tree.
 			The default mode inherited from the scene tree root is [constant MERGING_MODE_ON].

doc/classes/VisualServer.xml

@@ -1462,14 +1462,6 @@
 				Once finished with your RID, you will want to free the RID using the VisualServer's [method free_rid] static method.
 			</description>
 		</method>
-		<method name="instance_geometry_set_as_instance_lod">
-			<return type="void" />
-			<argument index="0" name="instance" type="RID" />
-			<argument index="1" name="as_lod_of_instance" type="RID" />
-			<description>
-				Not implemented in Godot 3.x.
-			</description>
-		</method>
 		<method name="instance_geometry_set_cast_shadows_setting">
 			<return type="void" />
 			<argument index="0" name="instance" type="RID" />
@@ -1478,17 +1470,6 @@
 				Sets the shadow casting setting to one of [enum ShadowCastingSetting]. Equivalent to [member GeometryInstance.cast_shadow].
 			</description>
 		</method>
-		<method name="instance_geometry_set_draw_range">
-			<return type="void" />
-			<argument index="0" name="instance" type="RID" />
-			<argument index="1" name="min" type="float" />
-			<argument index="2" name="max" type="float" />
-			<argument index="3" name="min_margin" type="float" />
-			<argument index="4" name="max_margin" type="float" />
-			<description>
-				Not implemented in Godot 3.x.
-			</description>
-		</method>
 		<method name="instance_geometry_set_flag">
 			<return type="void" />
 			<argument index="0" name="instance" type="RID" />

editor/editor_node.cpp

@@ -1347,7 +1347,17 @@ void EditorNode::_find_node_types(Node *p_node, int &count_2d, int &count_3d) {
 void EditorNode::_save_scene_with_preview(String p_file, int p_idx) {
 	EditorProgress save("save", TTR("Saving Scene"), 4);
 
+	Ref<World> edited_world;
+
 	if (editor_data.get_edited_scene_root() != nullptr) {
+		// Allow a generic mechanism for the engine to make changes prior, and after saving.
+		if (editor_data.get_edited_scene_root()->get_tree() && editor_data.get_edited_scene_root()->get_tree()->get_root()) {
+			edited_world = editor_data.get_edited_scene_root()->get_tree()->get_root()->get_world();
+			if (edited_world.is_valid()) {
+				edited_world->notify_saving(true);
+			}
+		}
+
 		save.step(TTR("Analyzing"), 0);
 
 		int c2d = 0;
@@ -1428,6 +1438,10 @@ void EditorNode::_save_scene_with_preview(String p_file, int p_idx) {
 	save.step(TTR("Saving Scene"), 4);
 	_save_scene(p_file, p_idx);
 
+	if (edited_world.is_valid()) {
+		edited_world->notify_saving(false);
+	}
+
 	if (!singleton->cmdline_export_mode) {
 		EditorResourcePreview::get_singleton()->check_for_invalidation(p_file);
 	}

editor/icons/icon_l_o_d.svg

@@ -0,0 +1 @@
+<svg height="16" viewBox="0 0 16 16" width="16" xmlns="http://www.w3.org/2000/svg"><path d="m7.8914071 1.0013383-4.4946196 2.5949697-.4014433 6.2245994 5.5913828 2.7646396 4.49462-2.5949696.401443-6.2245994zm.1158866 1.9307015 2.4790833 2.563918.980876 3.428908-2.9964126 1.7299802-2.4790831-2.5639184-.9808766-3.428908z" fill="#fc9c9c" transform="matrix(1.0011971 .5780414 -.5780414 1.0011971 3.677961 -3.564097)"/></svg>

editor/plugins/spatial_editor_plugin.cpp

@@ -45,6 +45,7 @@
 #include "editor/spatial_editor_gizmos.h"
 #include "scene/3d/camera.h"
 #include "scene/3d/collision_shape.h"
+#include "scene/3d/lod_manager.h"
 #include "scene/3d/mesh_instance.h"
 #include "scene/3d/physics_body.h"
 #include "scene/3d/room_manager.h"
@@ -2735,7 +2736,12 @@ void SpatialEditorViewport::_notification(int p_what) {
 		} else {
 			set_freelook_active(false);
 		}
+
 		call_deferred("update_transform_gizmo_view");
+
+		if (camera) {
+			camera->set_affect_lod(visible);
+		}
 	}
 
 	if (p_what == NOTIFICATION_RESIZED) {
@@ -5503,6 +5509,14 @@ void SpatialEditor::_menu_item_pressed(int p_option) {
 			VisualServer::get_singleton()->set_use_occlusion_culling(!is_checked);
 			view_menu->get_popup()->set_item_checked(checkbox_id, !is_checked);
 
+		} break;
+		case MENU_VIEW_LEVEL_OF_DETAIL: {
+			int checkbox_id = view_menu->get_popup()->get_item_index(p_option);
+			bool is_checked = view_menu->get_popup()->is_item_checked(checkbox_id);
+			LODManager::set_enabled(!is_checked);
+			view_menu->get_popup()->set_item_checked(checkbox_id, !is_checked);
+			EditorNode::get_singleton()->get_scene_tree_dock()->get_tree_editor()->update_tree();
+
 		} break;
 		case MENU_VIEW_CAMERA_SETTINGS: {
 			settings_dialog->popup_centered(settings_vbc->get_combined_minimum_size() + Size2(50, 50));
@@ -7076,6 +7090,7 @@ SpatialEditor::SpatialEditor(EditorNode *p_editor) {
 	p->add_check_shortcut(ED_SHORTCUT("spatial_editor/view_grid", TTR("View Grid"), KEY_NUMBERSIGN), MENU_VIEW_GRID);
 	p->add_check_shortcut(ED_SHORTCUT("spatial_editor/view_portal_culling", TTR("View Portal Culling"), KEY_MASK_ALT | KEY_P), MENU_VIEW_PORTAL_CULLING);
 	p->add_check_shortcut(ED_SHORTCUT("spatial_editor/view_occlusion_culling", TTR("View Occlusion Culling")), MENU_VIEW_OCCLUSION_CULLING);
+	p->add_check_shortcut(ED_SHORTCUT("spatial_editor/view_level_of_detail", TTR("View Level of Detail")), MENU_VIEW_LEVEL_OF_DETAIL);
 
 	p->add_separator();
 	p->add_shortcut(ED_SHORTCUT("spatial_editor/settings", TTR("Settings...")), MENU_VIEW_CAMERA_SETTINGS);
@@ -7083,6 +7098,7 @@ SpatialEditor::SpatialEditor(EditorNode *p_editor) {
 	p->set_item_checked(p->get_item_index(MENU_VIEW_ORIGIN), true);
 	p->set_item_checked(p->get_item_index(MENU_VIEW_GRID), true);
 	p->set_item_checked(p->get_item_index(MENU_VIEW_OCCLUSION_CULLING), true);
+	p->set_item_checked(p->get_item_index(MENU_VIEW_LEVEL_OF_DETAIL), true);
 
 	p->connect("id_pressed", this, "_menu_item_pressed");
 

editor/plugins/spatial_editor_plugin.h

@@ -674,6 +674,7 @@ private:
 		MENU_VIEW_GRID,
 		MENU_VIEW_PORTAL_CULLING,
 		MENU_VIEW_OCCLUSION_CULLING,
+		MENU_VIEW_LEVEL_OF_DETAIL,
 		MENU_VIEW_GIZMOS_3D_ICONS,
 		MENU_VIEW_CAMERA_SETTINGS,
 		MENU_LOCK_SELECTED,

editor/scene_tree_editor.cpp

@@ -36,6 +36,7 @@
 #include "editor/node_dock.h"
 #include "editor/plugins/animation_player_editor_plugin.h"
 #include "editor/plugins/canvas_item_editor_plugin.h"
+#include "scene/3d/lod_manager.h"
 #include "scene/gui/label.h"
 #include "scene/main/viewport.h"
 #include "scene/resources/packed_scene.h"
@@ -162,7 +163,7 @@ void SceneTreeEditor::_toggle_visible(Node *p_node) {
 	}
 }
 
-void SceneTreeEditor::_add_nodes(Node *p_node, TreeItem *p_parent) {
+void SceneTreeEditor::_add_nodes(Node *p_node, TreeItem *p_parent, bool p_disable_visibility) {
 	if (!p_node) {
 		return;
 	}
@@ -405,9 +406,9 @@ void SceneTreeEditor::_add_nodes(Node *p_node, TreeItem *p_parent) {
 
 			bool v = p_node->call("is_visible");
 			if (v) {
-				item->add_button(0, get_icon("GuiVisibilityVisible", "EditorIcons"), BUTTON_VISIBILITY, false, TTR("Toggle Visibility"));
+				item->add_button(0, get_icon("GuiVisibilityVisible", "EditorIcons"), BUTTON_VISIBILITY, p_disable_visibility, TTR("Toggle Visibility"));
 			} else {
-				item->add_button(0, get_icon("GuiVisibilityHidden", "EditorIcons"), BUTTON_VISIBILITY, false, TTR("Toggle Visibility"));
+				item->add_button(0, get_icon("GuiVisibilityHidden", "EditorIcons"), BUTTON_VISIBILITY, p_disable_visibility, TTR("Toggle Visibility"));
 			}
 
 			if (!p_node->is_connected("visibility_changed", this, "_node_visibility_changed")) {
@@ -437,8 +438,12 @@ void SceneTreeEditor::_add_nodes(Node *p_node, TreeItem *p_parent) {
 		item->set_as_cursor(0);
 	}
 
+	// In some cases we want to disable visibility control by the user
+	// for automatically visibility-controlled children.
+	bool disable_visibility = p_node->is_class("LOD") && LODManager::is_enabled();
+
 	for (int i = 0; i < p_node->get_child_count(); i++) {
-		_add_nodes(p_node->get_child(i), item);
+		_add_nodes(p_node->get_child(i), item, disable_visibility);
 	}
 
 	if (valid_types.size()) {

editor/scene_tree_editor.h

@@ -73,7 +73,7 @@ class SceneTreeEditor : public Control {
 
 	void _compute_hash(Node *p_node, uint64_t &hash);
 
-	void _add_nodes(Node *p_node, TreeItem *p_parent);
+	void _add_nodes(Node *p_node, TreeItem *p_parent, bool p_disable_visibility = false);
 	void _test_update_tree();
 	void _update_tree(bool p_scroll_to_selected = false);
 	bool _update_filter(TreeItem *p_parent = nullptr, bool p_scroll_to_selected = false);

scene/3d/camera.cpp

@@ -504,6 +504,8 @@ void Camera::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_doppler_tracking"), &Camera::get_doppler_tracking);
 	ClassDB::bind_method(D_METHOD("get_frustum"), &Camera::get_frustum);
 	ClassDB::bind_method(D_METHOD("get_camera_rid"), &Camera::get_camera);
+	ClassDB::bind_method(D_METHOD("set_affect_lod", "enable"), &Camera::set_affect_lod);
+	ClassDB::bind_method(D_METHOD("get_affect_lod"), &Camera::get_affect_lod);
 
 	ClassDB::bind_method(D_METHOD("set_cull_mask_bit", "layer", "enable"), &Camera::set_cull_mask_bit);
 	ClassDB::bind_method(D_METHOD("get_cull_mask_bit", "layer"), &Camera::get_cull_mask_bit);
@@ -523,6 +525,7 @@ void Camera::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::VECTOR2, "frustum_offset"), "set_frustum_offset", "get_frustum_offset");
 	ADD_PROPERTY(PropertyInfo(Variant::REAL, "near", PROPERTY_HINT_EXP_RANGE, "0.01,8192,0.01,or_greater"), "set_znear", "get_znear");
 	ADD_PROPERTY(PropertyInfo(Variant::REAL, "far", PROPERTY_HINT_EXP_RANGE, "0.1,8192,0.1,or_greater"), "set_zfar", "get_zfar");
+	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "affect_lod"), "set_affect_lod", "get_affect_lod");
 
 	BIND_ENUM_CONSTANT(PROJECTION_PERSPECTIVE);
 	BIND_ENUM_CONSTANT(PROJECTION_ORTHOGONAL);

scene/3d/camera.h

@@ -88,6 +88,7 @@ private:
 
 	DopplerTracking doppler_tracking;
 	Ref<SpatialVelocityTracker> velocity_tracker;
+	bool affect_lod = true;
 
 protected:
 	void _update_camera();
@@ -170,6 +171,9 @@ public:
 
 	Vector3 get_doppler_tracked_velocity() const;
 
+	void set_affect_lod(bool p_enable) { affect_lod = p_enable; }
+	bool get_affect_lod() const { return affect_lod; }
+
 	Camera();
 	~Camera();
 };

scene/3d/lod.cpp

@@ -0,0 +1,250 @@
+/**************************************************************************/
+/*  lod.cpp                                                               */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* 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 "lod.h"
+
+#include "core/engine.h"
+#include "scene/3d/visual_instance.h"
+
+void LOD::_lod_register() {
+	if (!data.registered) {
+		Ref<World> world = get_world();
+		ERR_FAIL_COND(!world.is_valid());
+		world->_register_lod(this, data.queue_id);
+		data.registered = true;
+	}
+}
+
+void LOD::_lod_unregister() {
+	if (data.registered) {
+		Ref<World> world = get_world();
+		ERR_FAIL_COND(!world.is_valid());
+		world->_unregister_lod(this, data.queue_id);
+		data.registered = false;
+	}
+}
+
+void LOD::_notification(int p_what) {
+	switch (p_what) {
+		case NOTIFICATION_ENTER_TREE: {
+			if (is_visible_in_tree()) {
+				_lod_register();
+			}
+		} break;
+		case NOTIFICATION_EXIT_TREE: {
+			if (is_visible_in_tree()) {
+				_lod_unregister();
+			}
+		} break;
+		case NOTIFICATION_VISIBILITY_CHANGED: {
+			if (is_inside_tree()) {
+				if (is_visible_in_tree()) {
+					_lod_register();
+				} else {
+					_lod_unregister();
+				}
+			}
+		} break;
+		default:
+			break;
+	}
+}
+
+void LOD::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("set_hysteresis", "distance"), &LOD::set_hysteresis);
+	ClassDB::bind_method(D_METHOD("get_hysteresis"), &LOD::get_hysteresis);
+
+	ADD_PROPERTY(PropertyInfo(Variant::REAL, "hysteresis", PROPERTY_HINT_RANGE, "0,1024,0.01,or_greater"), "set_hysteresis", "get_hysteresis");
+
+	ClassDB::bind_method(D_METHOD("set_lod_priority", "priority"), &LOD::set_lod_priority);
+	ClassDB::bind_method(D_METHOD("get_lod_priority"), &LOD::get_lod_priority);
+	ADD_PROPERTY(PropertyInfo(Variant::INT, "lod_priority", PROPERTY_HINT_RANGE, "0,4"), "set_lod_priority", "get_lod_priority");
+}
+
+void LOD::set_hysteresis(real_t p_distance) {
+	data.hysteresis = CLAMP((float)p_distance, 0.0f, 100000.0f);
+}
+
+void LOD::set_lod_priority(int p_priority) {
+	// We are just using priority as a user facing
+	// description. Internally we use queues.
+	int queue_id = CLAMP(p_priority, 0, 4);
+
+	if (queue_id == data.queue_id) {
+		return;
+	}
+
+	if (is_inside_tree()) {
+		// If already in the world, we must remove the LOD
+		// and re-add in a different queue.
+		Ref<World> world = get_world();
+		ERR_FAIL_COND(!world.is_valid());
+		world->_unregister_lod(this, data.queue_id);
+
+		data.queue_id = queue_id;
+
+		world->_register_lod(this, data.queue_id);
+	} else {
+		data.queue_id = queue_id;
+	}
+}
+
+void LOD::_lod_pre_save() {
+	// The pre-save is primarily for the editor,
+	// to ensure that saved scenes do not have unnecessary
+	// diffs because of changes to which LOD child is active.
+	// We standardize on just showing the first child in saved scenes.
+	_update_child_distances();
+
+	int32_t num_lods = data.lod_children.size();
+
+	// Make first visible, and all others invisible.
+	data.current_lod_child = 0;
+
+	for (int32_t n = 0; n < num_lods; n++) {
+		uint32_t child_id = data.lod_children[n].child_id;
+		Spatial *child = Object::cast_to<Spatial>(get_child(child_id));
+
+		if (child) {
+			child->set_visible(n == data.current_lod_child);
+		}
+	}
+}
+
+// Returns whether a visibility change was triggered.
+bool LOD::_lod_update(float p_camera_dist_squared) {
+	// This should later be done as a one-off, as
+	// this is expensive.
+	_update_child_distances();
+
+	int32_t num_lods = data.lod_children.size();
+
+	// LOD node has no valid children to update.
+	if (!num_lods) {
+		return false;
+	}
+
+	data.current_lod_child = MIN(data.current_lod_child, num_lods - 1);
+	int32_t curr = data.current_lod_child;
+
+	float dist = Math::sqrt(p_camera_dist_squared);
+
+	bool changed = true;
+
+	while (changed) {
+		changed = false;
+		if ((curr < num_lods - 1) && (dist >= (data.lod_children[curr + 1].distance) + data.hysteresis)) {
+			// Lower detail.
+			curr += 1;
+			changed = true;
+		}
+
+		if (curr && (dist < data.lod_children[curr].distance)) {
+			// Increase detail.
+			curr -= 1;
+			changed = true;
+		}
+	}
+
+	// No change?
+	if ((curr == data.current_lod_child) && (data.current_lod_node == get_child(data.lod_children[curr].child_id))) {
+		return false;
+	}
+
+	data.current_lod_child = curr;
+
+	// Make current visible, and all others invisible.
+	for (int32_t n = 0; n < num_lods; n++) {
+		uint32_t child_id = data.lod_children[n].child_id;
+
+		Spatial *child = Object::cast_to<Spatial>(get_child(child_id));
+
+		if (child) {
+			child->set_visible(n == curr);
+			if (n == curr) {
+				data.current_lod_node = child;
+			}
+		}
+	}
+
+	return true;
+}
+
+void LOD::_update_child_distances() {
+	// Reserve enough space for all children, assuming they are all valid.
+	LODChild *lod_children = (LODChild *)alloca(sizeof(LODChild) * get_child_count());
+
+	// Reset prior to loop.
+	float total_dist = 0.0f;
+	uint32_t valid_count = 0;
+
+#ifdef TOOLS_ENABLED
+	bool is_editor = Engine::get_singleton()->is_editor_hint();
+	uint32_t visible_count = 0;
+#endif
+
+	// Check every possible node child, not all will be valid lod children.
+	for (int32_t n = 0; n < get_child_count(); n++) {
+		// Destination for a valid child.
+		LODChild &lod_child = lod_children[valid_count];
+
+		const Spatial *child = Object::cast_to<Spatial>(get_child(n));
+		if (child) {
+			// Fill the data.
+			lod_child.distance = total_dist;
+			lod_child.child_id = n;
+
+			// Keep running total of the distance range used by each lod child.
+			total_dist += child->get_lod_range();
+
+#ifdef TOOLS_ENABLED
+			if (is_editor && child->is_visible()) {
+				visible_count++;
+			}
+#endif
+			valid_count++;
+		}
+	}
+
+	// Size the actual vector, and copy data across.
+	data.lod_children.resize(valid_count);
+	if (valid_count) {
+		memcpy(&data.lod_children[0], lod_children, valid_count * sizeof(LODChild));
+	}
+
+#ifdef TOOLS_ENABLED
+	// Something external has changed the visibilities of the children,
+	// such as the editor.
+	if (is_editor && visible_count != 1) {
+		// Force the current child to reset.
+		data.current_lod_child = -1;
+	}
+#endif
+}

scene/3d/lod.h

@@ -0,0 +1,73 @@
+/**************************************************************************/
+/*  lod.h                                                                 */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* 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 LOD_H
+#define LOD_H
+
+#include "spatial.h"
+
+class LOD : public Spatial {
+	GDCLASS(LOD, Spatial);
+
+	struct LODChild {
+		float distance;
+		int32_t child_id;
+	};
+
+	struct Data {
+		LocalVector<LODChild> lod_children;
+		int32_t current_lod_child = 0;
+		float hysteresis = 1.0f;
+		int32_t queue_id = 0;
+		const Spatial *current_lod_node = nullptr;
+		bool registered = false;
+	} data;
+
+	friend class LODManager;
+	bool _lod_update(float p_camera_dist_squared);
+	void _lod_pre_save();
+	void _update_child_distances();
+
+	void _lod_register();
+	void _lod_unregister();
+
+protected:
+	void _notification(int p_what);
+	static void _bind_methods();
+
+public:
+	void set_hysteresis(real_t p_distance);
+	real_t get_hysteresis() const { return data.hysteresis; }
+
+	void set_lod_priority(int p_priority);
+	int get_lod_priority() const { return data.queue_id; }
+};
+
+#endif // LOD_H

scene/3d/lod_manager.cpp

@@ -0,0 +1,182 @@
+/**************************************************************************/
+/*  lod_manager.cpp                                                       */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* 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 "lod_manager.h"
+
+#include "scene/3d/camera.h"
+#include "scene/3d/lod.h"
+
+bool LODManager::_enabled = true;
+
+void LODManager::register_camera(Camera *p_camera) {
+	DEV_ASSERT(p_camera);
+	data.cameras.push_back(p_camera);
+}
+
+void LODManager::remove_camera(Camera *p_camera) {
+	data.cameras.erase(p_camera);
+}
+
+void LODManager::register_lod(LOD *p_lod, uint32_t p_queue_id) {
+	ERR_FAIL_UNSIGNED_INDEX(p_queue_id, NUM_LOD_QUEUES);
+	data.queues[p_queue_id].lods.push_back(p_lod);
+}
+
+void LODManager::unregister_lod(LOD *p_lod, uint32_t p_queue_id) {
+	ERR_FAIL_UNSIGNED_INDEX(p_queue_id, NUM_LOD_QUEUES);
+	data.queues[p_queue_id].lods.erase(p_lod);
+}
+
+void LODManager::_update_queue(uint32_t p_queue_id, const Vector3 *p_camera_positions, uint32_t p_num_cameras) {
+	// Some local aliases.
+	Queue &queue = data.queues[p_queue_id];
+	LocalVector<LOD *> &lods = queue.lods;
+
+	uint32_t total_lods = lods.size();
+
+	if (!total_lods) {
+		return;
+	}
+
+	// Wraparound.
+	queue.lod_iterator %= total_lods;
+
+	uint32_t first_lod = queue.lod_iterator;
+
+	uint32_t num_lods_to_check = 1;
+	uint32_t num_lods_to_change = 1;
+
+	switch (p_queue_id) {
+		case 4: {
+			num_lods_to_check = 3125;
+			num_lods_to_change = 32;
+		} break;
+		case 3: {
+			num_lods_to_check = 256;
+			num_lods_to_change = 8;
+		} break;
+		case 2: {
+			num_lods_to_check = 27;
+			num_lods_to_change = 4;
+		} break;
+		case 1: {
+			num_lods_to_check = 4;
+			num_lods_to_change = 1;
+		} break;
+		default: {
+		} break;
+	}
+
+	// No point updating more lods than the total.
+	num_lods_to_check = MIN(num_lods_to_check, total_lods);
+	num_lods_to_change = MIN(num_lods_to_change, total_lods);
+
+	// Find minimum distances to cameras...
+	uint32_t changed = 0;
+
+	for (uint32_t l = 0; l < num_lods_to_check; l++) {
+		uint32_t lod_id = (first_lod + l) % total_lods;
+		LOD *lod = lods[lod_id];
+		Vector3 lod_pos = lod->get_global_translation();
+
+		float min_dist = FLT_MAX;
+		for (uint32_t c = 0; c < p_num_cameras; c++) {
+			float dist = (lod_pos - p_camera_positions[c]).length_squared();
+			min_dist = MIN(min_dist, dist);
+		}
+
+		if (lod->_lod_update(min_dist)) {
+			changed++;
+			if (changed >= num_lods_to_change) {
+				// Only update the iterator to where we got to.
+				num_lods_to_check = l + 1;
+				break;
+			}
+		}
+	}
+
+	queue.lod_iterator += num_lods_to_check;
+}
+
+void LODManager::notify_saving(bool p_active) {
+	// When saving in the editor, to prevent file delta due to
+	// different visibilities from LOD childs, we standardize
+	// to showing the first LOD.
+	MutexLock lock(data.mutex);
+	data.saving = p_active;
+
+	if (p_active) {
+		for (uint32_t n = 0; n < NUM_LOD_QUEUES; n++) {
+			Queue &queue = data.queues[n];
+			LocalVector<LOD *> &lods = queue.lods;
+
+			for (uint32_t l = 0; l < lods.size(); l++) {
+				lods[l]->_lod_pre_save();
+			}
+		}
+	}
+}
+
+void LODManager::update() {
+	if (!_enabled) {
+		return;
+	}
+
+	MutexLock lock(data.mutex);
+
+	// We don't want to change the visibilities while saving from the editor.
+	if (data.saving) {
+		return;
+	}
+
+	// Get all camera positions
+	// Reserve enough for all cameras, some may not be used.
+	Vector3 *camera_positions = (Vector3 *)alloca(data.cameras.size() * sizeof(Vector3));
+
+	uint32_t num_cameras = 0;
+	for (uint32_t c = 0; c < data.cameras.size(); c++) {
+		const Camera *camera = data.cameras[c];
+
+		// Ignore ortho cameras for LOD.
+		if (!camera->get_affect_lod() || !camera->is_current() || (camera->get_projection() == Camera::PROJECTION_ORTHOGONAL)) {
+			continue;
+		}
+
+		camera_positions[num_cameras++] = camera->get_global_transform().origin;
+	}
+
+	if (!num_cameras) {
+		return;
+	}
+
+	for (uint32_t n = 0; n < NUM_LOD_QUEUES; n++) {
+		_update_queue(n, camera_positions, num_cameras);
+	}
+}

scene/3d/lod_manager.h

@@ -0,0 +1,74 @@
+/**************************************************************************/
+/*  lod_manager.h                                                         */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* 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 LOD_MANAGER_H
+#define LOD_MANAGER_H
+
+#include "core/local_vector.h"
+#include "core/os/mutex.h"
+
+class Camera;
+class LOD;
+struct Vector3;
+
+class LODManager {
+public:
+	enum { NUM_LOD_QUEUES = 5 };
+
+	void register_camera(Camera *p_camera);
+	void remove_camera(Camera *p_camera);
+	void register_lod(LOD *p_lod, uint32_t p_queue_id);
+	void unregister_lod(LOD *p_lod, uint32_t p_queue_id);
+	void update();
+
+	void notify_saving(bool p_active);
+
+	static void set_enabled(bool p_enabled) { _enabled = p_enabled; }
+	static bool is_enabled() { return _enabled; }
+
+private:
+	void _update_queue(uint32_t p_queue_id, const Vector3 *p_camera_positions, uint32_t p_num_cameras);
+
+	struct Queue {
+		LocalVector<LOD *> lods;
+		uint32_t lod_iterator = 0;
+	};
+
+	struct Data {
+		LocalVector<Camera *> cameras;
+		Queue queues[NUM_LOD_QUEUES];
+		BinaryMutex mutex;
+		bool saving = false;
+	} data;
+
+	static bool _enabled;
+};
+
+#endif // LOD_MANAGER_H

scene/3d/spatial.cpp

@@ -915,6 +915,10 @@ void Spatial::set_merging_mode(MergingMode p_mode) {
 	_propagate_merging_allowed(merging_allowed);
 }
 
+void Spatial::set_lod_range(float p_range) {
+	data.lod_range = p_range;
+}
+
 void Spatial::force_update_transform() {
 	ERR_FAIL_COND(!is_inside_tree());
 	if (!xform_change.in_list()) {
@@ -993,6 +997,9 @@ void Spatial::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_merging_mode", "mode"), &Spatial::set_merging_mode);
 	ClassDB::bind_method(D_METHOD("get_merging_mode"), &Spatial::get_merging_mode);
 
+	ClassDB::bind_method(D_METHOD("set_lod_range", "range"), &Spatial::set_lod_range);
+	ClassDB::bind_method(D_METHOD("get_lod_range"), &Spatial::get_lod_range);
+
 	ClassDB::bind_method(D_METHOD("to_local", "global_point"), &Spatial::to_local);
 	ClassDB::bind_method(D_METHOD("to_global", "local_point"), &Spatial::to_global);
 
@@ -1024,6 +1031,7 @@ void Spatial::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "visible"), "set_visible", "is_visible");
 	ADD_PROPERTY(PropertyInfo(Variant::OBJECT, "gizmo", PROPERTY_HINT_RESOURCE_TYPE, "SpatialGizmo", 0), "set_gizmo", "get_gizmo");
 	ADD_GROUP("Misc", "");
+	ADD_PROPERTY(PropertyInfo(Variant::REAL, "lod_range", PROPERTY_HINT_RANGE, "0,1024,0.01,or_greater"), "set_lod_range", "get_lod_range");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "merging_mode", PROPERTY_HINT_ENUM, "Inherit,Off,On"), "set_merging_mode", "get_merging_mode");
 
 	ADD_SIGNAL(MethodInfo("visibility_changed"));

scene/3d/spatial.h

@@ -115,6 +115,7 @@ private:
 		List<Spatial *> children;
 		List<Spatial *>::Element *C;
 
+		float lod_range = 10.0f;
 		ClientPhysicsInterpolationData *client_physics_interpolation_data;
 
 #ifdef TOOLS_ENABLED
@@ -248,6 +249,9 @@ public:
 
 	void force_update_transform();
 
+	void set_lod_range(float p_range);
+	float get_lod_range() const { return data.lod_range; }
+
 	Spatial();
 	~Spatial();
 };

scene/3d/visual_instance.cpp

@@ -266,42 +266,6 @@ GeometryInstance::LightmapScale GeometryInstance::get_lightmap_scale() const {
 	return lightmap_scale;
 }
 
-void GeometryInstance::set_lod_min_distance(float p_dist) {
-	lod_min_distance = p_dist;
-	VS::get_singleton()->instance_geometry_set_draw_range(get_instance(), lod_min_distance, lod_max_distance, lod_min_hysteresis, lod_max_hysteresis);
-}
-
-float GeometryInstance::get_lod_min_distance() const {
-	return lod_min_distance;
-}
-
-void GeometryInstance::set_lod_max_distance(float p_dist) {
-	lod_max_distance = p_dist;
-	VS::get_singleton()->instance_geometry_set_draw_range(get_instance(), lod_min_distance, lod_max_distance, lod_min_hysteresis, lod_max_hysteresis);
-}
-
-float GeometryInstance::get_lod_max_distance() const {
-	return lod_max_distance;
-}
-
-void GeometryInstance::set_lod_min_hysteresis(float p_dist) {
-	lod_min_hysteresis = p_dist;
-	VS::get_singleton()->instance_geometry_set_draw_range(get_instance(), lod_min_distance, lod_max_distance, lod_min_hysteresis, lod_max_hysteresis);
-}
-
-float GeometryInstance::get_lod_min_hysteresis() const {
-	return lod_min_hysteresis;
-}
-
-void GeometryInstance::set_lod_max_hysteresis(float p_dist) {
-	lod_max_hysteresis = p_dist;
-	VS::get_singleton()->instance_geometry_set_draw_range(get_instance(), lod_min_distance, lod_max_distance, lod_min_hysteresis, lod_max_hysteresis);
-}
-
-float GeometryInstance::get_lod_max_hysteresis() const {
-	return lod_max_hysteresis;
-}
-
 void GeometryInstance::_notification(int p_what) {
 }
 
@@ -367,18 +331,6 @@ void GeometryInstance::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_lightmap_scale", "scale"), &GeometryInstance::set_lightmap_scale);
 	ClassDB::bind_method(D_METHOD("get_lightmap_scale"), &GeometryInstance::get_lightmap_scale);
 
-	ClassDB::bind_method(D_METHOD("set_lod_max_hysteresis", "mode"), &GeometryInstance::set_lod_max_hysteresis);
-	ClassDB::bind_method(D_METHOD("get_lod_max_hysteresis"), &GeometryInstance::get_lod_max_hysteresis);
-
-	ClassDB::bind_method(D_METHOD("set_lod_max_distance", "mode"), &GeometryInstance::set_lod_max_distance);
-	ClassDB::bind_method(D_METHOD("get_lod_max_distance"), &GeometryInstance::get_lod_max_distance);
-
-	ClassDB::bind_method(D_METHOD("set_lod_min_hysteresis", "mode"), &GeometryInstance::set_lod_min_hysteresis);
-	ClassDB::bind_method(D_METHOD("get_lod_min_hysteresis"), &GeometryInstance::get_lod_min_hysteresis);
-
-	ClassDB::bind_method(D_METHOD("set_lod_min_distance", "mode"), &GeometryInstance::set_lod_min_distance);
-	ClassDB::bind_method(D_METHOD("get_lod_min_distance"), &GeometryInstance::get_lod_min_distance);
-
 	ClassDB::bind_method(D_METHOD("set_extra_cull_margin", "margin"), &GeometryInstance::set_extra_cull_margin);
 	ClassDB::bind_method(D_METHOD("get_extra_cull_margin"), &GeometryInstance::get_extra_cull_margin);
 
@@ -397,12 +349,6 @@ void GeometryInstance::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "generate_lightmap"), "set_generate_lightmap", "get_generate_lightmap");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "lightmap_scale", PROPERTY_HINT_ENUM, "1x,2x,4x,8x"), "set_lightmap_scale", "get_lightmap_scale");
 
-	ADD_GROUP("LOD", "lod_");
-	ADD_PROPERTY(PropertyInfo(Variant::INT, "lod_min_distance", PROPERTY_HINT_RANGE, "0,32768,0.01"), "set_lod_min_distance", "get_lod_min_distance");
-	ADD_PROPERTY(PropertyInfo(Variant::INT, "lod_min_hysteresis", PROPERTY_HINT_RANGE, "0,32768,0.01"), "set_lod_min_hysteresis", "get_lod_min_hysteresis");
-	ADD_PROPERTY(PropertyInfo(Variant::INT, "lod_max_distance", PROPERTY_HINT_RANGE, "0,32768,0.01"), "set_lod_max_distance", "get_lod_max_distance");
-	ADD_PROPERTY(PropertyInfo(Variant::INT, "lod_max_hysteresis", PROPERTY_HINT_RANGE, "0,32768,0.01"), "set_lod_max_hysteresis", "get_lod_max_hysteresis");
-
 	//ADD_SIGNAL( MethodInfo("visibility_changed"));
 
 	BIND_ENUM_CONSTANT(LIGHTMAP_SCALE_1X);
@@ -422,11 +368,6 @@ void GeometryInstance::_bind_methods() {
 }
 
 GeometryInstance::GeometryInstance() {
-	lod_min_distance = 0;
-	lod_max_distance = 0;
-	lod_min_hysteresis = 0;
-	lod_max_hysteresis = 0;
-
 	for (int i = 0; i < FLAG_MAX; i++) {
 		flags[i] = false;
 	}

scene/3d/visual_instance.h

@@ -121,10 +121,6 @@ private:
 	ShadowCastingSetting shadow_casting_setting;
 	Ref<Material> material_override;
 	Ref<Material> material_overlay;
-	float lod_min_distance;
-	float lod_max_distance;
-	float lod_min_hysteresis;
-	float lod_max_hysteresis;
 
 	float extra_cull_margin;
 
@@ -145,18 +141,6 @@ public:
 	void set_lightmap_scale(LightmapScale p_scale);
 	LightmapScale get_lightmap_scale() const;
 
-	void set_lod_min_distance(float p_dist);
-	float get_lod_min_distance() const;
-
-	void set_lod_max_distance(float p_dist);
-	float get_lod_max_distance() const;
-
-	void set_lod_min_hysteresis(float p_dist);
-	float get_lod_min_hysteresis() const;
-
-	void set_lod_max_hysteresis(float p_dist);
-	float get_lod_max_hysteresis() const;
-
 	virtual void set_material_override(const Ref<Material> &p_material);
 	Ref<Material> get_material_override() const;
 

scene/register_scene_types.cpp

@@ -194,6 +194,7 @@
 #include "scene/3d/label_3d.h"
 #include "scene/3d/light.h"
 #include "scene/3d/listener.h"
+#include "scene/3d/lod.h"
 #include "scene/3d/merge_group.h"
 #include "scene/3d/mesh_instance.h"
 #include "scene/3d/multimesh_instance.h"
@@ -441,6 +442,7 @@ void register_scene_types() {
 	ClassDB::register_class<ARVROrigin>();
 	ClassDB::register_class<InterpolatedCamera>();
 	ClassDB::register_class<MeshInstance>();
+	ClassDB::register_class<LOD>();
 	ClassDB::register_class<ImmediateGeometry>();
 	ClassDB::register_virtual_class<SpriteBase3D>();
 	ClassDB::register_class<Sprite3D>();

scene/resources/world.cpp

@@ -33,6 +33,7 @@
 #include "core/math/camera_matrix.h"
 #include "core/math/octree.h"
 #include "scene/3d/camera.h"
+#include "scene/3d/lod_manager.h"
 #include "scene/3d/visibility_notifier.h"
 #include "scene/scene_string_names.h"
 #include "servers/navigation_server.h"
@@ -216,6 +217,7 @@ struct SpatialIndexer {
 void World::_register_camera(Camera *p_camera) {
 #ifndef _3D_DISABLED
 	indexer->_add_camera(p_camera);
+	lod_manager->register_camera(p_camera);
 #endif
 }
 
@@ -227,6 +229,19 @@ void World::_update_camera(Camera *p_camera) {
 void World::_remove_camera(Camera *p_camera) {
 #ifndef _3D_DISABLED
 	indexer->_remove_camera(p_camera);
+	lod_manager->remove_camera(p_camera);
+#endif
+}
+
+void World::_register_lod(LOD *p_lod, uint32_t p_queue_id) {
+#ifndef _3D_DISABLED
+	lod_manager->register_lod(p_lod, p_queue_id);
+#endif
+}
+
+void World::_unregister_lod(LOD *p_lod, uint32_t p_queue_id) {
+#ifndef _3D_DISABLED
+	lod_manager->unregister_lod(p_lod, p_queue_id);
 #endif
 }
 
@@ -251,6 +266,7 @@ void World::_remove_notifier(VisibilityNotifier *p_notifier) {
 void World::_update(uint64_t p_frame) {
 #ifndef _3D_DISABLED
 	indexer->_update(p_frame);
+	lod_manager->update();
 #endif
 }
 
@@ -314,6 +330,12 @@ void World::get_camera_list(List<Camera *> *r_cameras) {
 	}
 }
 
+void World::notify_saving(bool p_active) {
+	if (lod_manager) {
+		lod_manager->notify_saving(p_active);
+	}
+}
+
 void World::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("get_space"), &World::get_space);
 	ClassDB::bind_method(D_METHOD("get_scenario"), &World::get_scenario);
@@ -355,6 +377,7 @@ World::World() {
 	indexer = NULL;
 #else
 	indexer = memnew(SpatialIndexer);
+	lod_manager = memnew(LODManager);
 #endif
 }
 
@@ -365,5 +388,7 @@ World::~World() {
 
 #ifndef _3D_DISABLED
 	memdelete(indexer);
+	memdelete(lod_manager);
+	lod_manager = nullptr;
 #endif
 }

scene/resources/world.h

@@ -38,7 +38,9 @@
 
 class Camera;
 class VisibilityNotifier;
+class LOD;
 struct SpatialIndexer;
+class LODManager;
 
 class World : public Resource {
 	GDCLASS(World, Resource);
@@ -50,6 +52,7 @@ private:
 	RID navigation_map;
 
 	SpatialIndexer *indexer;
+	LODManager *lod_manager = nullptr;
 	Ref<Environment> environment;
 	Ref<Environment> fallback_environment;
 
@@ -58,6 +61,7 @@ protected:
 
 	friend class Camera;
 	friend class VisibilityNotifier;
+	friend class LOD;
 
 	void _register_camera(Camera *p_camera);
 	void _update_camera(Camera *p_camera);
@@ -66,6 +70,10 @@ protected:
 	void _register_notifier(VisibilityNotifier *p_notifier, const AABB &p_rect);
 	void _update_notifier(VisibilityNotifier *p_notifier, const AABB &p_rect);
 	void _remove_notifier(VisibilityNotifier *p_notifier);
+
+	void _register_lod(LOD *p_lod, uint32_t p_queue_id);
+	void _unregister_lod(LOD *p_lod, uint32_t p_queue_id);
+
 	friend class Viewport;
 	void _update(uint64_t p_frame);
 
@@ -84,6 +92,8 @@ public:
 
 	PhysicsDirectSpaceState *get_direct_space_state();
 
+	void notify_saving(bool p_active);
+
 	World();
 	~World();
 };

servers/visual/visual_server_raster.h

@@ -658,9 +658,6 @@ public:
 	BIND2(instance_geometry_set_material_override, RID, RID)
 	BIND2(instance_geometry_set_material_overlay, RID, RID)
 
-	BIND5(instance_geometry_set_draw_range, RID, float, float, float, float)
-	BIND2(instance_geometry_set_as_instance_lod, RID, RID)
-
 #undef BINDBASE
 //from now on, calls forwarded to this singleton
 #define BINDBASE VSG::canvas

servers/visual/visual_server_scene.cpp

@@ -2027,11 +2027,6 @@ void VisualServerScene::instance_geometry_set_material_overlay(RID p_instance, R
 	}
 }
 
-void VisualServerScene::instance_geometry_set_draw_range(RID p_instance, float p_min, float p_max, float p_min_margin, float p_max_margin) {
-}
-void VisualServerScene::instance_geometry_set_as_instance_lod(RID p_instance, RID p_as_lod_of_instance) {
-}
-
 void VisualServerScene::_update_instance(Instance *p_instance) {
 	p_instance->version++;
 

servers/visual/visual_server_scene.h

@@ -892,9 +892,6 @@ public:
 	virtual void instance_geometry_set_material_override(RID p_instance, RID p_material);
 	virtual void instance_geometry_set_material_overlay(RID p_instance, RID p_material);
 
-	virtual void instance_geometry_set_draw_range(RID p_instance, float p_min, float p_max, float p_min_margin, float p_max_margin);
-	virtual void instance_geometry_set_as_instance_lod(RID p_instance, RID p_as_lod_of_instance);
-
 	_FORCE_INLINE_ void _update_instance(Instance *p_instance);
 	_FORCE_INLINE_ void _update_instance_aabb(Instance *p_instance);
 	_FORCE_INLINE_ void _update_dirty_instance(Instance *p_instance);

servers/visual/visual_server_wrap_mt.h

@@ -566,9 +566,6 @@ public:
 	FUNC2(instance_geometry_set_material_override, RID, RID)
 	FUNC2(instance_geometry_set_material_overlay, RID, RID)
 
-	FUNC5(instance_geometry_set_draw_range, RID, float, float, float, float)
-	FUNC2(instance_geometry_set_as_instance_lod, RID, RID)
-
 	/* CANVAS (2D) */
 
 	FUNCRID(canvas)

servers/visual_server.cpp

@@ -2188,8 +2188,6 @@ void VisualServer::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("instance_geometry_set_cast_shadows_setting", "instance", "shadow_casting_setting"), &VisualServer::instance_geometry_set_cast_shadows_setting);
 	ClassDB::bind_method(D_METHOD("instance_geometry_set_material_override", "instance", "material"), &VisualServer::instance_geometry_set_material_override);
 	ClassDB::bind_method(D_METHOD("instance_geometry_set_material_overlay", "instance", "material"), &VisualServer::instance_geometry_set_material_overlay);
-	ClassDB::bind_method(D_METHOD("instance_geometry_set_draw_range", "instance", "min", "max", "min_margin", "max_margin"), &VisualServer::instance_geometry_set_draw_range);
-	ClassDB::bind_method(D_METHOD("instance_geometry_set_as_instance_lod", "instance", "as_lod_of_instance"), &VisualServer::instance_geometry_set_as_instance_lod);
 
 	ClassDB::bind_method(D_METHOD("instances_cull_aabb", "aabb", "scenario"), &VisualServer::_instances_cull_aabb_bind, DEFVAL(RID()));
 	ClassDB::bind_method(D_METHOD("instances_cull_ray", "from", "to", "scenario"), &VisualServer::_instances_cull_ray_bind, DEFVAL(RID()));

servers/visual_server.h

@@ -1001,9 +1001,6 @@ public:
 	virtual void instance_geometry_set_material_override(RID p_instance, RID p_material) = 0;
 	virtual void instance_geometry_set_material_overlay(RID p_instance, RID p_material) = 0;
 
-	virtual void instance_geometry_set_draw_range(RID p_instance, float p_min, float p_max, float p_min_margin, float p_max_margin) = 0;
-	virtual void instance_geometry_set_as_instance_lod(RID p_instance, RID p_as_lod_of_instance) = 0;
-
 	/* CANVAS (2D) */
 
 	virtual RID canvas_create() = 0;