Add Extra Anchorpoints

Only for circles? Rotate 45 degrees and add extremes, then rotate back if you like.

Or in the middle of all segments of all sorts of shapes? That is a task for a script:

for thisPath in Layer.paths:
	# step backwards through nodes so we do not mess up point indexes:
	for thisNode in thisPath.nodes[::-1]:
		if thisNode.type != OFFCURVE:
			# on-curve index + 0.5 is the center of the segment:
			pathTime = thisNode.index+0.5
			thisPath.insertNodeWithPathTime_(pathTime)

(Sidenote: Please use the term on-curve because anchor means something else in fontmaking land.)

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