There’s an implementation of a shadow buffered display driver in telescope. It’s not well-documented, but it comports to the specification set out in the display’s documentation, which is required reading if you want to play with the graphics acceleration engine.
Many of the implemented API calls related to drawing modes have been written and tested to some extent, but do not feature in the implementation of telescope. I had fun playing around with the scrolling modes and the box drawing and it all worked.
The diff-based update engine in use in telescope is well-appropriate to a scope, with few pixels changing each update. Depending on your needs, you may wish to use other re-map modes for better performance in complex scenes.
There are some builds of it starting about here:
As you can see in that thread, the diff engine in the final build was 4x faster than the full-column write in the initial builds, but only for the scope. It will be slower for a full-screen redraw, which is capped at 141 Hz, IIRC.