Table 1: Spatial relations defined in terms of C [18].


DC a is disconnected from b C
P a is part of b
PP a is a proper part of b P  P
EQ a is identical with b P  P
O a overlaps b P P
DR a is discrete from b O
PO a partially overlaps b O P P
EC a is externally connected to b C  ¬ O
TPP a is a tangential proper part of b PP EC  EC
NTPP a is a nontangential proper part of b PP  ¬  EC  EC