Implement game camera override

Implemented uniform API in Viewport class to override 2D and/or
3D camera.

Added buttons in 2D and 3D editor viewport toolbars that override
the running game camera transform with the editor viewport camera
transform. Implemented via remote debugger protocol and camera
override API.

Removed LiveEditFuncs function pointers from ScriptDebugger class.
Since the debugger got access to the SceneTree instance (if one
exists), there is no need to store the function pointers. The live
edit functions in SceneTree are used directly instead. Also removed
the static version of live edit functions in SceneTree for the same
reason. This reduced the SceneTree -> Debugger coupling too since
the function pointers don't need to be set from SceneTree anymore.

Moved script_debugger_remote.h/cpp from 'core/' to 'scene/debugger/'.
This is because the remote debugger is now using SceneTree directly
and 'core/' classes should not depend on 'scene/' classes.

4 files changed, 127 insertions, 5 deletions

diff --git a/editor/plugins/canvas_item_editor_plugin.cpp b/editor/plugins/canvas_item_editor_plugin.cpp
index f9a7b7caf1..7db05ab270 100644
--- a/editor/plugins/canvas_item_editor_plugin.cpp
+++ b/editor/plugins/canvas_item_editor_plugin.cpp
@@ -3730,6 +3730,7 @@ void CanvasItemEditor::_notification(int p_what) {
 		grid_snap_button->set_icon(get_icon("SnapGrid", "EditorIcons"));
 		snap_config_menu->set_icon(get_icon("GuiTabMenu", "EditorIcons"));
 		skeleton_menu->set_icon(get_icon("Bone", "EditorIcons"));
+		override_camera_button->set_icon(get_icon("Camera2D", "EditorIcons"));
 		pan_button->set_icon(get_icon("ToolPan", "EditorIcons"));
 		ruler_button->set_icon(get_icon("Ruler", "EditorIcons"));
 		pivot_button->set_icon(get_icon("EditPivot", "EditorIcons"));
@@ -3799,6 +3800,15 @@ void CanvasItemEditor::_notification(int p_what) {
 
 		anchor_mode_button->set_icon(get_icon("Anchor", "EditorIcons"));
 	}
+
+	if (p_what == NOTIFICATION_VISIBILITY_CHANGED) {
+		if (!is_visible() && override_camera_button->is_pressed()) {
+			ScriptEditorDebugger *debugger = ScriptEditor::get_singleton()->get_debugger();
+
+			debugger->set_camera_override(ScriptEditorDebugger::OVERRIDE_NONE);
+			override_camera_button->set_pressed(false);
+		}
+	}
 }
 
 void CanvasItemEditor::_selection_changed() {
@@ -4140,6 +4150,15 @@ void CanvasItemEditor::_button_toggle_grid_snap(bool p_status) {
 	grid_snap_active = p_status;
 	viewport->update();
 }
+void CanvasItemEditor::_button_override_camera(bool p_pressed) {
+	ScriptEditorDebugger *debugger = ScriptEditor::get_singleton()->get_debugger();
+
+	if (p_pressed) {
+		debugger->set_camera_override(ScriptEditorDebugger::OVERRIDE_2D);
+	} else {
+		debugger->set_camera_override(ScriptEditorDebugger::OVERRIDE_NONE);
+	}
+}
 
 void CanvasItemEditor::_button_tool_select(int p_index) {
 
@@ -4237,6 +4256,17 @@ void CanvasItemEditor::_button_toggle_anchor_mode(bool p_status) {
 	viewport->update();
 }
 
+void CanvasItemEditor::_update_override_camera_button(bool p_game_running) {
+	if (p_game_running) {
+		override_camera_button->set_disabled(false);
+		override_camera_button->set_tooltip(TTR("Game camera override\nOverrides game camera with editor viewport camera."));
+	} else {
+		override_camera_button->set_disabled(true);
+		override_camera_button->set_pressed(false);
+		override_camera_button->set_tooltip(TTR("Game camera override\nNo game instance running."));
+	}
+}
+
 void CanvasItemEditor::_popup_callback(int p_op) {
 
 	last_option = MenuOption(p_op);
@@ -4829,6 +4859,8 @@ void CanvasItemEditor::_bind_methods() {
 	ClassDB::bind_method("_button_zoom_plus", &CanvasItemEditor::_button_zoom_plus);
 	ClassDB::bind_method("_button_toggle_smart_snap", &CanvasItemEditor::_button_toggle_smart_snap);
 	ClassDB::bind_method("_button_toggle_grid_snap", &CanvasItemEditor::_button_toggle_grid_snap);
+	ClassDB::bind_method(D_METHOD("_button_override_camera", "pressed"), &CanvasItemEditor::_button_override_camera);
+	ClassDB::bind_method(D_METHOD("_update_override_camera_button", "game_running"), &CanvasItemEditor::_update_override_camera_button);
 	ClassDB::bind_method("_button_toggle_anchor_mode", &CanvasItemEditor::_button_toggle_anchor_mode);
 	ClassDB::bind_method("_update_scroll", &CanvasItemEditor::_update_scroll);
 	ClassDB::bind_method("_update_scrollbars", &CanvasItemEditor::_update_scrollbars);
@@ -5141,6 +5173,9 @@ CanvasItemEditor::CanvasItemEditor(EditorNode *p_editor) {
 	editor_selection->connect("selection_changed", this, "update");
 	editor_selection->connect("selection_changed", this, "_selection_changed");
 
+	editor->call_deferred("connect", "play_pressed", this, "_update_override_camera_button", make_binds(true));
+	editor->call_deferred("connect", "stop_pressed", this, "_update_override_camera_button", make_binds(false));
+
 	hb = memnew(HBoxContainer);
 	add_child(hb);
 	hb->set_anchors_and_margins_preset(Control::PRESET_WIDE);
@@ -5385,6 +5420,15 @@ CanvasItemEditor::CanvasItemEditor(EditorNode *p_editor) {
 
 	hb->add_child(memnew(VSeparator));
 
+	override_camera_button = memnew(ToolButton);
+	hb->add_child(override_camera_button);
+	override_camera_button->connect("toggled", this, "_button_override_camera");
+	override_camera_button->set_toggle_mode(true);
+	override_camera_button->set_disabled(true);
+	_update_override_camera_button(false);
+
+	hb->add_child(memnew(VSeparator));
+
 	view_menu = memnew(MenuButton);
 	view_menu->set_text(TTR("View"));
 	hb->add_child(view_menu);
diff --git a/editor/plugins/canvas_item_editor_plugin.h b/editor/plugins/canvas_item_editor_plugin.h
index 480fb89621..4b419ffcce 100644
--- a/editor/plugins/canvas_item_editor_plugin.h
+++ b/editor/plugins/canvas_item_editor_plugin.h
@@ -360,6 +360,7 @@ private:
 	ToolButton *ungroup_button;
 
 	MenuButton *skeleton_menu;
+	ToolButton *override_camera_button;
 	MenuButton *view_menu;
 	HBoxContainer *animation_hb;
 	MenuButton *animation_menu;
@@ -533,8 +534,11 @@ private:
 	void _button_zoom_plus();
 	void _button_toggle_smart_snap(bool p_status);
 	void _button_toggle_grid_snap(bool p_status);
+	void _button_override_camera(bool p_pressed);
 	void _button_tool_select(int p_index);
 
+	void _update_override_camera_button(bool p_game_running);
+
 	HSplitContainer *palette_split;
 	VSplitContainer *bottom_split;
 
diff --git a/editor/plugins/spatial_editor_plugin.cpp b/editor/plugins/spatial_editor_plugin.cpp
index 1d8fd38858..29ae57af18 100644
--- a/editor/plugins/spatial_editor_plugin.cpp
+++ b/editor/plugins/spatial_editor_plugin.cpp
@@ -901,6 +901,8 @@ void SpatialEditorViewport::_sinput(const Ref<InputEvent> &p_event) {
 	Ref<InputEventMouseButton> b = p_event;
 
 	if (b.is_valid()) {
+		emit_signal("clicked", this);
+
 		float zoom_factor = 1 + (ZOOM_MULTIPLIER - 1) * b->get_factor();
 		switch (b->get_button_index()) {
 
@@ -3096,6 +3098,7 @@ void SpatialEditorViewport::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("drop_data_fw"), &SpatialEditorViewport::drop_data_fw);
 
 	ADD_SIGNAL(MethodInfo("toggle_maximize_view", PropertyInfo(Variant::OBJECT, "viewport")));
+	ADD_SIGNAL(MethodInfo("clicked", PropertyInfo(Variant::OBJECT, "viewport")));
 }
 
 void SpatialEditorViewport::reset() {
@@ -4369,6 +4372,19 @@ void SpatialEditor::_menu_item_toggled(bool pressed, int p_option) {
 			tool_option_button[TOOL_OPT_USE_SNAP]->set_pressed(pressed);
 			snap_enabled = pressed;
 		} break;
+
+		case MENU_TOOL_OVERRIDE_CAMERA: {
+			ScriptEditorDebugger *const debugger = ScriptEditor::get_singleton()->get_debugger();
+
+			if (pressed) {
+				using Override = ScriptEditorDebugger::CameraOverride;
+
+				debugger->set_camera_override((Override)(Override::OVERRIDE_3D_1 + camera_override_viewport_id));
+			} else {
+				debugger->set_camera_override(ScriptEditorDebugger::OVERRIDE_NONE);
+			}
+
+		} break;
 	}
 }
 
@@ -4396,6 +4412,35 @@ void SpatialEditor::_menu_gizmo_toggled(int p_option) {
 	update_all_gizmos();
 }
 
+void SpatialEditor::_update_camera_override_button(bool p_game_running) {
+	Button *const button = tool_option_button[TOOL_OPT_OVERRIDE_CAMERA];
+
+	if (p_game_running) {
+		button->set_disabled(false);
+		button->set_tooltip(TTR("Game camera override\nNo game instance running."));
+	} else {
+		button->set_disabled(true);
+		button->set_pressed(false);
+		button->set_tooltip(TTR("Game camera override\nOverrides game camera with editor viewport camera."));
+	}
+}
+
+void SpatialEditor::_update_camera_override_viewport(Object *p_viewport) {
+	SpatialEditorViewport *current_viewport = Object::cast_to<SpatialEditorViewport>(p_viewport);
+
+	if (!current_viewport)
+		return;
+
+	ScriptEditorDebugger *const debugger = ScriptEditor::get_singleton()->get_debugger();
+
+	camera_override_viewport_id = current_viewport->index;
+	if (debugger->get_camera_override() >= ScriptEditorDebugger::OVERRIDE_3D_1) {
+		using Override = ScriptEditorDebugger::CameraOverride;
+
+		debugger->set_camera_override((Override)(Override::OVERRIDE_3D_1 + camera_override_viewport_id));
+	}
+}
+
 void SpatialEditor::_menu_item_pressed(int p_option) {
 
 	switch (p_option) {
@@ -5290,6 +5335,7 @@ void SpatialEditor::_notification(int p_what) {
 
 		tool_option_button[SpatialEditor::TOOL_OPT_LOCAL_COORDS]->set_icon(get_icon("Object", "EditorIcons"));
 		tool_option_button[SpatialEditor::TOOL_OPT_USE_SNAP]->set_icon(get_icon("Snap", "EditorIcons"));
+		tool_option_button[SpatialEditor::TOOL_OPT_OVERRIDE_CAMERA]->set_icon(get_icon("Camera", "EditorIcons"));
 
 		view_menu->get_popup()->set_item_icon(view_menu->get_popup()->get_item_index(MENU_VIEW_USE_1_VIEWPORT), get_icon("Panels1", "EditorIcons"));
 		view_menu->get_popup()->set_item_icon(view_menu->get_popup()->get_item_index(MENU_VIEW_USE_2_VIEWPORTS), get_icon("Panels2", "EditorIcons"));
@@ -5305,6 +5351,9 @@ void SpatialEditor::_notification(int p_what) {
 		get_tree()->connect("node_removed", this, "_node_removed");
 		EditorNode::get_singleton()->get_scene_tree_dock()->get_tree_editor()->connect("node_changed", this, "_refresh_menu_icons");
 		editor_selection->connect("selection_changed", this, "_refresh_menu_icons");
+
+		editor->connect("stop_pressed", this, "_update_camera_override_button", make_binds(false));
+		editor->connect("play_pressed", this, "_update_camera_override_button", make_binds(true));
 	} else if (p_what == NOTIFICATION_ENTER_TREE) {
 
 		_register_all_gizmos();
@@ -5339,6 +5388,13 @@ void SpatialEditor::_notification(int p_what) {
 		// Update grid color by rebuilding grid.
 		_finish_grid();
 		_init_grid();
+	} else if (p_what == NOTIFICATION_VISIBILITY_CHANGED) {
+		if (!is_visible() && tool_option_button[TOOL_OPT_OVERRIDE_CAMERA]->is_pressed()) {
+			ScriptEditorDebugger *debugger = ScriptEditor::get_singleton()->get_debugger();
+
+			debugger->set_camera_override(ScriptEditorDebugger::OVERRIDE_NONE);
+			tool_option_button[TOOL_OPT_OVERRIDE_CAMERA]->set_pressed(false);
+		}
 	}
 }
 
@@ -5483,6 +5539,8 @@ void SpatialEditor::_bind_methods() {
 	ClassDB::bind_method("_request_gizmo", &SpatialEditor::_request_gizmo);
 	ClassDB::bind_method("_toggle_maximize_view", &SpatialEditor::_toggle_maximize_view);
 	ClassDB::bind_method("_refresh_menu_icons", &SpatialEditor::_refresh_menu_icons);
+	ClassDB::bind_method("_update_camera_override_button", &SpatialEditor::_update_camera_override_button);
+	ClassDB::bind_method("_update_camera_override_viewport", &SpatialEditor::_update_camera_override_viewport);
 
 	ADD_SIGNAL(MethodInfo("transform_key_request"));
 	ADD_SIGNAL(MethodInfo("item_lock_status_changed"));
@@ -5536,6 +5594,8 @@ SpatialEditor::SpatialEditor(EditorNode *p_editor) {
 	snap_key_enabled = false;
 	tool_mode = TOOL_MODE_SELECT;
 
+	camera_override_viewport_id = 0;
+
 	hbc_menu = memnew(HBoxContainer);
 	vbc->add_child(hbc_menu);
 
@@ -5633,6 +5693,17 @@ SpatialEditor::SpatialEditor(EditorNode *p_editor) {
 
 	hbc_menu->add_child(memnew(VSeparator));
 
+	tool_option_button[TOOL_OPT_OVERRIDE_CAMERA] = memnew(ToolButton);
+	hbc_menu->add_child(tool_option_button[TOOL_OPT_OVERRIDE_CAMERA]);
+	tool_option_button[TOOL_OPT_OVERRIDE_CAMERA]->set_toggle_mode(true);
+	tool_option_button[TOOL_OPT_OVERRIDE_CAMERA]->set_flat(true);
+	tool_option_button[TOOL_OPT_OVERRIDE_CAMERA]->set_disabled(true);
+	button_binds.write[0] = MENU_TOOL_OVERRIDE_CAMERA;
+	tool_option_button[TOOL_OPT_OVERRIDE_CAMERA]->connect("toggled", this, "_menu_item_toggled", button_binds);
+	_update_camera_override_button(false);
+
+	hbc_menu->add_child(memnew(VSeparator));
+
 	// Drag and drop support;
 	preview_node = memnew(Spatial);
 	preview_bounds = AABB();
@@ -5721,6 +5792,7 @@ SpatialEditor::SpatialEditor(EditorNode *p_editor) {
 
 		viewports[i] = memnew(SpatialEditorViewport(this, editor, i));
 		viewports[i]->connect("toggle_maximize_view", this, "_toggle_maximize_view");
+		viewports[i]->connect("clicked", this, "_update_camera_override_viewport");
 		viewports[i]->assign_pending_data_pointers(preview_node, &preview_bounds, accept);
 		viewport_base->add_child(viewports[i]);
 	}
diff --git a/editor/plugins/spatial_editor_plugin.h b/editor/plugins/spatial_editor_plugin.h
index fe91c33642..65e3c32ca8 100644
--- a/editor/plugins/spatial_editor_plugin.h
+++ b/editor/plugins/spatial_editor_plugin.h
@@ -494,6 +494,7 @@ public:
 
 		TOOL_OPT_LOCAL_COORDS,
 		TOOL_OPT_USE_SNAP,
+		TOOL_OPT_OVERRIDE_CAMERA,
 		TOOL_OPT_MAX
 
 	};
@@ -559,6 +560,7 @@ private:
 		MENU_TOOL_LIST_SELECT,
 		MENU_TOOL_LOCAL_COORDS,
 		MENU_TOOL_USE_SNAP,
+		MENU_TOOL_OVERRIDE_CAMERA,
 		MENU_TRANSFORM_CONFIGURE_SNAP,
 		MENU_TRANSFORM_DIALOG,
 		MENU_VIEW_USE_1_VIEWPORT,
@@ -585,9 +587,6 @@ private:
 	PopupMenu *gizmos_menu;
 	MenuButton *view_menu;
 
-	ToolButton *lock_button;
-	ToolButton *unlock_button;
-
 	AcceptDialog *accept;
 
 	ConfirmationDialog *snap_dialog;
@@ -615,13 +614,16 @@ private:
 	void _menu_item_pressed(int p_option);
 	void _menu_item_toggled(bool pressed, int p_option);
 	void _menu_gizmo_toggled(int p_option);
+	void _update_camera_override_button(bool p_game_running);
+	void _update_camera_override_viewport(Object *p_viewport);
 
 	HBoxContainer *hbc_menu;
 
 	void _generate_selection_box();
 	UndoRedo *undo_redo;
 
-	void _instance_scene();
+	int camera_override_viewport_id;
+
 	void _init_indicators();
 	void _update_gizmos_menu();
 	void _update_gizmos_menu_theme();
@@ -716,7 +718,7 @@ public:
 	void set_can_preview(Camera *p_preview);
 
 	SpatialEditorViewport *get_editor_viewport(int p_idx) {
-		ERR_FAIL_INDEX_V(p_idx, 4, NULL);
+		ERR_FAIL_INDEX_V(p_idx, static_cast<int>(VIEWPORTS_COUNT), NULL);
 		return viewports[p_idx];
 	}