typedef enum {DM_POINTLOCATION_NONE, DM_POINTLOCATION_NEAREST, DM_POINTLOCATION_REMOVE} DMPointLocationType;
If a search using DM_POINTLOCATION_NONE fails, the failure is signaled with a negative cell number. On the other hand, if DM_POINTLOCATION_NEAREST is used, on failure, the (approximate) nearest point in the mesh is used, replacing the given point in the input vector. DM_POINTLOCATION_REMOVE returns values only for points which were located.