GitLab

* Most characters had some weird background
* NOT specifying the font on some renderText() invocation fixes it
* Increased font size (first line only) to hide explicit vs. implicit font differences

* Ignoring the aspect ratio during auto-fit stretches/compresses the curve strokes
* Keep aspect ratio and use manual scaling to avoid that
* Increased pen sizes and set nicer styles
* y-Axis ("stretcher") isn't needed anymore as we now retain the y-scaling with fixed ratio

of sliders

I am assuming that the initial lower frequency is 30 Hz.  Need to check code in this
respect.

Normalizing phase to LLO produced a misleading behavior when changing the orientation of LLO. Shifted relative phases to a more sensible convention

Add some frequency and amplitude modulation to the plot