konva

[slowkow]

https://github.com/konvajs/konva

This might be worth checking out :)

Example: https://konvajs.github.io/docs/sandbox/Free_Drawing.html

[slowkow]

Also d3.conventions for stacking several layers of HTML, SVG, and Canvas on top of each other on a shared coordinate system.

Great demo:

https://bl.ocks.org/1wheel/f9b9909f10ed0f01780c5338ad38bd50