Online demo: https://justinclift.github.io/wasmGraph4/
This renders points of a basic 2D equation, and it's first derivative, onto the canvas.
Use the wasd, arrow, and numpad keys (including + and -) to rotate the graph around the origin. Use the mouse wheel to zoom in and out.
The code for this started from https://github.com/stdiopt/gowasm-experiments, and has been fairly radically reworked from there. 😄