I’m trying to figure out how to take over the UI layer of Vorple like I can do with glk by making my own GlkOte object. Vorple doesn’t set up the main interface the way I need but I want to make use of the Javascript functionality.
It depends on what you want to do, but generally you manipulate the UI just as any other web page. See the Screen Effects and Status Line extensions for examples.
Use vorple.prompt.hide() to hide the original prompt, add your own input method and have it trigger vorple.prompt.queueCommand(cmd) (where cmd is the command) to pass commands to the engine.