Better stroke smoothing

[personalizedrefrigerator]

Currently, js-draw uses heuristics to fit pen input points to Bézier curves. The current stroke smoothing method leads to handwriting that looks somewhat like this:

While the current stroke smoother has the advantage of producing a small number of curves (good because js-draw drawings are uncompressed, Joplin seems not to support SVGZ), it makes handwriting somewhat difficult to read.

Progress

• So far, an InputStabilizer preprocessor has been created — it leads to better results, but also has delay.
• v1.15 should slightly improve this.
• https://github.com/personalizedrefrigerator/js-draw/tree/work/pressure-inference contains incomplete work done on making the default pen pressure sensitive (which should make strokes more readable).

[personalizedrefrigerator]

Related: personalizedrefrigerator/joplin-plugin-freehand-drawing#10

[personalizedrefrigerator]

Related: e328438