Snaking sliders are cut off

[itdelatrisu]

Snaking sliders should be rounded, but are cut off (in #205). This is noticeable with the higher-level slider changes in #211, when the end hit circle is faded in after snaking completes (as in osu!).

@mad-s, how difficult would it be to change this?

[mad-s]

It would not be too hard to implement.
My solution would be to draw a (semi-)cone at the end of the curve. I will probably be able to do it without uploading new geometry each frame using some vertex shader trickery.