[Liblas-devel] Drivers

[Mateusz Loskot]

Howard Butler wrote:
> A major impetus for this effort is to be able to provide abstract views to
> other LAS-like data formats using libLAS more transparently.  My
> experience with GDAL's driver-based approach informs (though Mateusz might
> say infects :) my sensibilities here, and what I would like to do is mimic
> its approach but in a much more limited way.

I have learned from GDAL/OGR nearly exactly the same what Frank has:

hobu: FrankW: I have a question about the driver registrars. Specifically,
if you were to do it again, would you do anything different?

FrankW: I'd provide a way, from the start, to open with a specific driver
instead of using the generic entry point.

The GDALOpen() is a waste of computational time and also potentially
error-prone point in a solution, in most of practical use
cases I've developing/seen myself.
In fact, we have learned here in libLAS that this kind of abstractions
are not necessarily best idea, vide LASFile.

It usually is and unnecessary abstraction and it does solve very little if
anything (I'm not speaking of applications like gdalinfo, one sink for all
which are rare though widely used cases).

> There are a number of data
> formats that are LAS-like that could fit well within this, including
> things like QFIT, TerraSolid .bin, a simplified Oracle Point Cloud driver,
> gzip/bzip/zip'd LAS, LizardTech's Lidar format, and ASCII-style ones like
> XYZ.
> I plan to build out LASDriver and implement drivers for the Oracle Point
> Cloud and TerraSolid .bin formats in the next months.  Consider this your
> notice of the work that is going on, and your task to think about other
> formats you would like implemented in libLAS :)  Also, if anyone has any
> concerns or comments about this idea, I would be excited to hear about
> them.

And LAS mnemonic will become redundant and confusing.

To keep my usually long stories short, I would leave libLAS alone
as it is and develop new library with a proper and extensible
data model and bunch of drivers. libLAS would be used by LAS driver.


Best regards,
-- 
Mateusz Loskot
http://mateusz.loskot.net