Developers are free to create and apply their own custom layout maps whenever they need it! You need a special layout for your app? Just go ahead and create it!
The existing layout endpoint is extended with the new parameter map.
The map is a JSON stringified list of box-definition-lists with x, y, width, height, and objectFit definitions for each box.
Here's an example map that places 2 boxes (640x360px) above eachother in the center of the video podium.
[
[320, 0, 640, 360, "auto"],
[320, 360, 640, 360, "auto"]
]