Merge pull request #75751 from KoBeWi/eradicate_ViewportTexture_errors_entirely_and_surely

Prevent errors when using ViewportTexture

doc/classes/Node.xml

@@ -500,6 +500,13 @@
 				Returns [code]true[/code] if the local system is the multiplayer authority of this node.
 			</description>
 		</method>
+		<method name="is_node_ready" qualifiers="const">
+			<return type="bool" />
+			<description>
+				Returns [code]true[/code] if the node is ready, i.e. it's inside scene tree and all its children are initialized.
+				[method request_ready] resets it back to [code]false[/code].
+			</description>
+		</method>
 		<method name="is_physics_processing" qualifiers="const">
 			<return type="bool" />
 			<description>

doc/classes/ViewportTexture.xml

@@ -6,7 +6,7 @@
 	<description>
 		Displays the content of a [Viewport] node as a dynamic [Texture2D]. This can be used to mix controls, 2D, and 3D elements in the same scene.
 		To create a ViewportTexture in code, use the [method Viewport.get_texture] method on the target viewport.
-		[b]Note:[/b] When local to scene, this texture uses [method Resource.setup_local_to_scene] to set the proxy texture and flags in the local viewport.
+		[b]Note:[/b] When local to scene, this texture uses [method Resource.setup_local_to_scene] to set the proxy texture and flags in the local viewport. Local to scene viewport textures will return incorrect data until the scene root is ready (see [signal Node.ready]).
 	</description>
 	<tutorials>
 		<link title="GUI in 3D Demo">https://godotengine.org/asset-library/asset/127</link>