viewport::render_direct_to_screen in Godot 3.2-alpha1
Godot 3.2 seems to have a new feature for a viewport: render_direct_to_screen.
According to the docs: https://github.com/godotengine/godot-docs/blob/master/classes/class_viewport.rst#id67
"If true, renders the Viewport directly to the screen instead of to the root viewport. Only available in GLES2. This is a low-level optimization and should not be used in most cases. If used, reading from the Viewport or from SCREEN_TEXTURE becomes unavailable. "
I'm experimenting with a split screen game, and because of weak performance this feature is exactly what I need.
But unfortunately if I enable it I only get a black rectangle for the viewport (I'm using GLES2).
I using this tutorial project for my experiments: http://kidscancode.org/blog/2018/07/godot3_splitscreen/
Can someone provide a working sample project for this new feature or can confirm this is a bug in the current 3.2-alpha1 (and master branch).