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).
Could you send me some of the outlines that I can have a look.
oftentimes in Glyphs, nudging back and forth by 1UPM can address rounding issues and the like, but I've never seen that strange wavy pattern before
edit: disregard me, Georg has entered the chat
Same UFO in RoboFont:
And @Thomas Phinney really just doing some exercises in computing béziers: (approximated) circles connected by paths with parametrically-controlled amount “pucker”. Still need to tweak it to avoid overlapping handles, and to more gracefully handle where two connectors overlap to make that angle smoother. Might take a stab at actually removing overlap/flattening into one curve as well.
You might want to draw the shapes in a way that they don’t overlap this way.
To show the problem. You can see the red line being on both sides of the black line and each time it crosses over Glyphs will add a node.
Sorry my geometric vocabulary is limited, but what I'm doing is currently is: given the desired angle of the control handle, find the points on the circles where the tangents are at that angle, and use those for the four corners of the "connector". I think theoretically if it weren't for rounding errors, that should never actually intersect the circle right? I wonder if I should also put on-curve points on the circle to make sure the curve is nudged just the right amount to fit on the unit grid (even if it ever-so-slightly distorts the circle)…