Closes: #300
K7GMQ3NNZF4Z4RVMTV7FXFDI3NJROAXWNHCH7Y6TYXPFW2Q2C37QC
N5UP6P3PMCBSSWFIEOJCZSWBYFDKWZFWBIRUOJQEJ453KZCHU4SAC
2GP4MXKEDQMZ7E6TCRSMV2AGN7HLEAHR3QEAC2QFCQQNPMNJSIHQC
7B74AT3BXYB7PVW4F6SGQNPMHOU5TEV5TZ54CG6VSQI46XSEKWXQC
c->prev = c->geom;