This function is only valid while looping with
int pcimport(int handle, string channel_name, <type>&value)
Imports data from the point cloud file into the given variable.
There are two special channel names you can import:
The number of the point being processed.
The distance of the point being processed from the query point. This is only available when iterating over unshaded points.
If the import succeeds the function overwrites this variable with the channel value.
1 if the import succeeded or
0 if the import failed (usually due to the given channel name not existing).