Can a plugin use features of the QT graphics engine beyond what's supported in the plugin API?
I would like to draw semi-transparent, filled rectangles in various colors over noteheads in a score, similar to what you would get with a highlighter. I understand that this isn't a feature of musescore itself and wouldn't exist in the plugin API. Is it possible to use the API for the underlying QT graphics engine to render such rectangles, and the plugin API to help determine the positioning and size?
If such a solution is possible, can any of the folks here offer a hint to get started? Is there another plugin that uses features of the graphic engine does this that I can study?