Fixes to 2D viewport

* Editor 2D viewport now uses embedded subwindows (windows no longer pop up)
* Restored the ability to disable 3D on the 2D viewport (makes 3D not display on 2D when there is a camera on the scene)

8 files changed, 35 insertions, 2 deletions

diff --git a/doc/classes/Viewport.xml b/doc/classes/Viewport.xml
index 292be34a0d..bc0c3c5516 100644
--- a/doc/classes/Viewport.xml
+++ b/doc/classes/Viewport.xml
@@ -208,6 +208,9 @@
 		<member name="debug_draw" type="int" setter="set_debug_draw" getter="get_debug_draw" enum="Viewport.DebugDraw" default="0">
 			The overlay mode for test rendered geometry in debug purposes.
 		</member>
+		<member name="disable_3d" type="bool" setter="set_disable_3d" getter="is_3d_disabled" default="false">
+			Disable 3D rendering (but keep 2D rendering).
+		</member>
 		<member name="global_canvas_transform" type="Transform2D" setter="set_global_canvas_transform" getter="get_global_canvas_transform">
 			The global canvas transform of the viewport. The canvas transform is relative to this.
 		</member>
diff --git a/editor/editor_node.cpp b/editor/editor_node.cpp
index 1bc04676b7..31f84d2508 100644
--- a/editor/editor_node.cpp
+++ b/editor/editor_node.cpp
@@ -6116,7 +6116,8 @@ EditorNode::EditorNode() {
 	scene_root_parent->set_v_size_flags(Control::SIZE_EXPAND_FILL);
 
 	scene_root = memnew(SubViewport);
-	//scene_root->set_usage(Viewport::USAGE_2D); canvas BG mode prevents usage of this as 2D
+	scene_root->set_embed_subwindows_hint(true);
+	scene_root->set_disable_3d(true);
 
 	RenderingServer::get_singleton()->viewport_set_hide_scenario(scene_root->get_viewport_rid(), true);
 	scene_root->set_disable_input(true);
diff --git a/scene/main/viewport.cpp b/scene/main/viewport.cpp
index cc56d6a49e..319e589036 100644
--- a/scene/main/viewport.cpp
+++ b/scene/main/viewport.cpp
@@ -929,6 +929,15 @@ bool Viewport::is_audio_listener_2d() const {
 	return audio_listener_2d;
 }
 
+void Viewport::set_disable_3d(bool p_disable) {
+	disable_3d = p_disable;
+	RenderingServer::get_singleton()->viewport_set_disable_3d(viewport, disable_3d);
+}
+
+bool Viewport::is_3d_disabled() const {
+	return disable_3d;
+}
+
 void Viewport::enable_canvas_transform_override(bool p_enable) {
 	if (override_canvas_transform == p_enable) {
 		return;
@@ -3516,6 +3525,9 @@ void Viewport::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_as_audio_listener_2d", "enable"), &Viewport::set_as_audio_listener_2d);
 	ClassDB::bind_method(D_METHOD("is_audio_listener_2d"), &Viewport::is_audio_listener_2d);
 
+	ClassDB::bind_method(D_METHOD("set_disable_3d", "disable"), &Viewport::set_disable_3d);
+	ClassDB::bind_method(D_METHOD("is_3d_disabled"), &Viewport::is_3d_disabled);
+
 	ClassDB::bind_method(D_METHOD("get_mouse_position"), &Viewport::get_mouse_position);
 	ClassDB::bind_method(D_METHOD("warp_mouse", "to_position"), &Viewport::warp_mouse);
 
@@ -3582,6 +3594,7 @@ void Viewport::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "snap_2d_transforms_to_pixel"), "set_snap_2d_transforms_to_pixel", "is_snap_2d_transforms_to_pixel_enabled");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "snap_2d_vertices_to_pixel"), "set_snap_2d_vertices_to_pixel", "is_snap_2d_vertices_to_pixel_enabled");
 	ADD_GROUP("Rendering", "");
+	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "disable_3d"), "set_disable_3d", "is_3d_disabled");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "msaa", PROPERTY_HINT_ENUM, "Disabled (Fastest),2x (Fast),4x (Average),8x (Slow),16x (Slower)"), "set_msaa", "get_msaa");
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "screen_space_aa", PROPERTY_HINT_ENUM, "Disabled (Fastest),FXAA (Fast)"), "set_screen_space_aa", "get_screen_space_aa");
 	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "use_debanding"), "set_use_debanding", "is_using_debanding");
diff --git a/scene/main/viewport.h b/scene/main/viewport.h
index d905e44a82..29491a1178 100644
--- a/scene/main/viewport.h
+++ b/scene/main/viewport.h
@@ -288,6 +288,8 @@ private:
 	void _update_listener();
 	void _update_listener_2d();
 
+	bool disable_3d = false;
+
 	void _propagate_enter_world(Node *p_node);
 	void _propagate_exit_world(Node *p_node);
 	void _propagate_viewport_notification(Node *p_node, int p_what);
@@ -503,6 +505,9 @@ public:
 	void set_as_audio_listener_2d(bool p_enable);
 	bool is_audio_listener_2d() const;
 
+	void set_disable_3d(bool p_disable);
+	bool is_3d_disabled() const;
+
 	void update_canvas_items();
 
 	Rect2 get_visible_rect() const;
diff --git a/servers/rendering/renderer_viewport.cpp b/servers/rendering/renderer_viewport.cpp
index e34d36bfff..2cf4c035a9 100644
--- a/servers/rendering/renderer_viewport.cpp
+++ b/servers/rendering/renderer_viewport.cpp
@@ -122,7 +122,7 @@ void RendererViewport::_draw_viewport(Viewport *p_viewport, uint32_t p_view_coun
 		}
 	}
 
-	bool can_draw_3d = RSG::scene->is_camera(p_viewport->camera);
+	bool can_draw_3d = RSG::scene->is_camera(p_viewport->camera) && !p_viewport->disable_3d;
 
 	if (p_viewport->clear_mode != RS::VIEWPORT_CLEAR_NEVER) {
 		if (p_viewport->transparent_bg) {
@@ -812,6 +812,13 @@ void RendererViewport::viewport_set_disable_environment(RID p_viewport, bool p_d
 	viewport->disable_environment = p_disable;
 }
 
+void RendererViewport::viewport_set_disable_3d(RID p_viewport, bool p_disable) {
+	Viewport *viewport = viewport_owner.getornull(p_viewport);
+	ERR_FAIL_COND(!viewport);
+
+	viewport->disable_3d = p_disable;
+}
+
 void RendererViewport::viewport_attach_camera(RID p_viewport, RID p_camera) {
 	Viewport *viewport = viewport_owner.getornull(p_viewport);
 	ERR_FAIL_COND(!viewport);
diff --git a/servers/rendering/renderer_viewport.h b/servers/rendering/renderer_viewport.h
index 8fedf32c04..ca40829648 100644
--- a/servers/rendering/renderer_viewport.h
+++ b/servers/rendering/renderer_viewport.h
@@ -71,6 +71,7 @@ public:
 		bool hide_scenario;
 		bool hide_canvas;
 		bool disable_environment;
+		bool disable_3d = false;
 		bool measure_render_time;
 
 		bool snap_2d_transforms_to_pixel;
@@ -220,6 +221,7 @@ public:
 	void viewport_set_hide_scenario(RID p_viewport, bool p_hide);
 	void viewport_set_hide_canvas(RID p_viewport, bool p_hide);
 	void viewport_set_disable_environment(RID p_viewport, bool p_disable);
+	void viewport_set_disable_3d(RID p_viewport, bool p_disable);
 
 	void viewport_attach_camera(RID p_viewport, RID p_camera);
 	void viewport_set_scenario(RID p_viewport, RID p_scenario);
diff --git a/servers/rendering/rendering_server_default.h b/servers/rendering/rendering_server_default.h
index 16e9f1fc77..b9afeafbab 100644
--- a/servers/rendering/rendering_server_default.h
+++ b/servers/rendering/rendering_server_default.h
@@ -585,6 +585,7 @@ public:
 	FUNC2(viewport_set_hide_scenario, RID, bool)
 	FUNC2(viewport_set_hide_canvas, RID, bool)
 	FUNC2(viewport_set_disable_environment, RID, bool)
+	FUNC2(viewport_set_disable_3d, RID, bool)
 
 	FUNC2(viewport_attach_camera, RID, RID)
 	FUNC2(viewport_set_scenario, RID, RID)
diff --git a/servers/rendering_server.h b/servers/rendering_server.h
index 594e2d885c..0a568eeb13 100644
--- a/servers/rendering_server.h
+++ b/servers/rendering_server.h
@@ -799,6 +799,7 @@ public:
 	virtual void viewport_set_hide_scenario(RID p_viewport, bool p_hide) = 0;
 	virtual void viewport_set_hide_canvas(RID p_viewport, bool p_hide) = 0;
 	virtual void viewport_set_disable_environment(RID p_viewport, bool p_disable) = 0;
+	virtual void viewport_set_disable_3d(RID p_viewport, bool p_disable) = 0;
 
 	virtual void viewport_attach_camera(RID p_viewport, RID p_camera) = 0;
 	virtual void viewport_set_scenario(RID p_viewport, RID p_scenario) = 0;