Is there some nice formula or algoritm for determining when a circle "hides"/intersects more than half of the perimeter of another circle, in a circle-circle interaction.
Example image: Two example circles on Wolframalpha
A way to either determine if more or less than half of the perimeter is "hidden" or a way to fully calculate the hidden perimeter length is desired.
radii, distance between circles, centers and intersection points (in a x-y coordinate system) are known.
Thanks in advance!