Internal_whether this constraint is currently pooled, in which case it should be ignored
Internal_whether both bodies are sleeping (set each frame before constraint solving)
index of first body
index of second body
constraint priority (higher = solved first)
whether constraint is enabled
unique constraint identifier
index from constraint ID
position iteration override (0 = use default)
velocity iteration override (0 = use default)
sequence number from constraint ID
user data
base constraint fields shared by all constraint types