So I've been experimenting with programmatically generating a font (as UFO), and have got things mostly working, but am noticing some strange "bumps" appearing where contours overlap. Nudging any of the on-curve or off-curve points just 1 unit seems to make them go away.
I'm seeing the bumps both in Glyphs preview and also in the exported fonts. Interestingly in the TrueType flavored version they show up as sharp 90º angles, whereas in the PS flavored OTF they show up as arcs.
Any ideas what's causing this? Tried googling and searching here to no avail.
They are extremely small though, and are only really visible at large sizes (this is a 1000 UPM font).