[pdal] reader plugin for Leica PTX

[Jed Frechette]

On  Thu, 17 Mar 2022 08:38:00 +0000 Daniel Brookes
<dbrookes at micromine.com> wrote
> Curious if there is any interest in supporting Leica PTX files in pdal.

PTX files are still used pretty commonly by people working with tripod
scanner data so I think supporting them does offer some value.

That being said, the main reason for a user to choose PTX over PTS
would be to store structured data and to preserve scan level
transforms. Therefore, as a user, a PTX reader that simply converts
the scan to an unstructured point cloud and bakes in the transform is
much less useful than one that preserves that information. Pretty much
any software that supports exporting PTX will also support exporting
PTS, since they were basically intended as the structured and
unstructured variants of an ascii exchange format.

e57 has a similar dichotomy, even though in that case you can store
either structured or unstructured data inside the same file. One core
PDAL feature that would make both PTX and e57 support a lot more
useful for structured data would be to simply add rowIndex and
columnIndex dimensions. As a user being able to load structured data
into PDAL, do some stuff to it, then save out structured data would be
really useful. Even if PDAL filters continue to only operate on
unstructured data and simply pass through the array indexes so that
the arrays can be reassembled by the writers that would open up a lot
of potential workflows.

Thanks,

-- 
Jed Frechette