Lem is the editor/IDE well-tuned for Common Lisp. https://lem-project.github.io
This is my notes from exploring some Lem codebase and few init files of other people.
The outermost display object.
Each pane which displays a buffer.
Arrangement of the windows.
- You can build a new arrangement and then set the window-tree of the frame to the new arrangement.
It's a moveable location in the buffer. Looks like all the implementations are based on operations on the points. Usually you can't create one directly, but you can move existing points.