Fw: Re: [Liblas-devel] Re: [GRASS-user] LiDAR LAS import

[Markus Metz]

On Wed, May 25, 2011 at 3:48 PM, Hamish <hamish_b at yahoo.com> wrote:
> fyi--
>
> --- On Wed, 5/25/11, Howard Butler <hobu.inc at gmail.com> wrote:
>> Cc: liblas-devel at lists.osgeo.org
>> Date: Wednesday, May 25, 2011, 6:34 AM
>>
>> Awesome news!  I'm glad the GRASS community (er, Markus rather)

A result of the GRASS code sprint where quite a few members of the
GRASS community came together

>> came together to get something done.  I hope it serves its
>> purpose well and beats las2txt | v.in.ascii by a lot.
>>
>> A few points I would like to clear up:
>>
>> - libLAS only supports 1.0, 1.1, 1.2, and 1.3 with support
>> for Point Formats 0-3 in those versions at this time

OK. Not even reading of point formats 4 and 5 ?

>> - OGR will most likely never support LAS or LAZ data
>> natively due to the fact that it isn't practical to stuff
>> millions of individual points into OGR's data model.

I take this as confirmation that using libLAS was the right approach
instead of waiting for OGR.

>> - I hope that Markus' v.in.lidar ingester is not doing
>> Seek() as part of its reading strategy.  Seek() on LAZ
>> data is going to be horribly slow

It uses the libLAS C API function LASReader_GetNextPoint() which
should read sequentially through the LAS file without seeking.

>>
>> Congrats Markus!

Thanks!

Markus M