It’s a winforms app, and there isn’t much nonstandard about it other than that large performance sensitive drawing apps are perhaps quite nonstandard to begin with. We want to handle some large cad scenarios in it (e.g smooth pan/zoom in drawings with 500k lines), it’s not the default use case, but it happens. The main advandtage over gdi+ ) is better support for retained mode drawing (record/playback style drawing), more efficient automatic culling, etc.