Implement worse Upsampling for more Oscilloscope-like look

Like https://dood.al/oscilloscope/, which features the best look of all simulators I know so far: > This uses an upsampling filter to simulate a digital-analogue converter between the computer and the oscilloscope. It turns sharp corners in the signal into curves, loops or ringing artefacts. If the page is running slowly, try disabling upsampling. It uses a Lanczos kernel, the code for that is here: https://git.s-ol.nu/xxy-oscilloscope/blob/master/oscilloscope.js#L-221 (not written by me, but looks port-able). That scope also has nice line-rendering in general, which is taken from [woscope](https://github.com/m1el/woscope) (docs here: http://m1el.github.io/woscope-how/). I'm not sure what your rendering is like at the moment, but it might be worth taking that in as well. Porting from WebGL should be pretty straightforward