The deformed fields of four synthetic point sets. (a)-(d) are the forward and backward deformed fields for data 1 to data 4 respectively. The up rows in (a)-(d) are the forward deformed fields, and the bottom rows in (a)-(d) are the backward deformed fields. From left to right: MCRPM, CRPM and RPM. The area marked by green cross is the topology non-preserving field.