This is a small demo of using the WRLD Unity SDK to place the map on any surface you want. The SDK just provides rendering the whole map according to the camera's view. So you can't limit that to a specific size.
This demo renders the map only inside the cube which acts like a stencil mask. The demo is heavily based on the excellent blog post from the WRLD guys which used this method for AR. Read part 1 and part 2 to understand what is done exactly.
If you move the map, it will automatically downloads the new map tiles and displays it. For using this demo you will need a valid API SDK key from WRLD, to get one just register at their website.
This demo includes the official WRLD Unity SDK from the asset store, have a look there for a newer version. The SDK was modified according to the changes mentioned in their blog posts.