An extremely fast way to draw and change lots of lines with minimal VRAM usage is to just overlay an ImageGraphic with another pygfx.Image object, and set the alpha of non-contour areas to 0. Would require a simple API to make contours indexable etc. for changing, and events.

Pygfx scaling can make this look decent!

In conjunction with a Heatmap and LinearRegionSelector this is the fastest way to have massive interactivity for calcium data. Connect the Heatmap LinearRegionSelector to a LineStack and limit the max shown temporal lines.