HTML DOM is slow. More apparent on low-end devices. Try this: render the static parts of each room to a single image using canvas and display that instead. Might reduce GPU render time. * Re-render when the resolution changes. See: https://developer.mozilla.org/en-US/docs/Web/API/Window/devicePixelRatio#monitoring_screen_resolution_or_zoom_level_changes
HTML DOM is slow. More apparent on low-end devices.
Try this: render the static parts of each room to a single image using canvas and display that instead. Might reduce GPU render time.