LASlib or liblas: document the choice

[EricBoix]

Issue by frogsapo Friday Apr 15, 2016 at 13:57 GMT Originally opened as https://github.com/MEPP-team/VCity/issues/98

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Concerning VCity LASlib dependency further inquire on the following:

• they are two libraries for reading LIDAR format: LASlib (which is part of LASTools and libLAS)
• VCity embarks an old version dating from 2014 of LASlib
  • libLAS is the packaged version for MacOSX. Is this also the case for Linux distros ?
  • The two libraries (libLAS and LASlib) have a common ancestor but are now diverging (refer to Utilities seciont): "Additionally, the libLAS version of the LAStools utilities are no longer command-line compatible. So while they may have some common heritage, and the two packages copy each other in terms of features and behaviors, they are now quite divergent."

Should VCity opt for LASlib or libLAS:

• No difference between the two solutions in terms of license (libLAS is BSD and LASlib is LGPL)
• lisLAS states: "As of 2014, libLAS has been almost entirely superceded by Martin Isenburg‘s LASlib library. The only functionality that libLAS provides over LASlib is the ability to work with GDAL-derived coordinate system information and reproject into infrequently-used coordinate systems."
• LibLAS and LASlib seem to agree on the following:
  • libLAS is a software component for LIDA data representation and LASlib is more processing oriented (watch out most processing is not open source though)
  • libLAS is commercial oriented (all BSD) whereas LASlib would be academic oriented (LGPL): this point is arguable though
  • LAStools (that uses LASlib) offer advanced (non open source) treatments.
• No found elements to compare the communities of users.
• LASlib seems to be a one man job although the Owning company is hard to evaluate in terms of contributors.
• libLAS comes packaged for MacOS and for some Unixes whereas you're on your own for LASlib. Neither of them uses cmake for its building.

[andredaa]

When trying to install 3DUSE the make fails, because it misses the LASLIB package. Make Error at CMakeLists.txt:375 (message): LASLIB not found. even though I installed LASTOOLS.zip sucessfully. Do you have an idea how to fix this?

[EricBoix]

@andredaa , 3DUse currently embarks its own copy of Laslib (in order to freeze the version). This embarked version needs to be installed manually as documented (e.g. for Ubuntu) in the manual installation of LASlib section of the installation docs. When your system is Linux/OSX, and if you chose to install LASlib somewhere in your user directory (as opposed to /usr/local e.g. because you don't have root or do not wish to mess up your /usr/local), you will then need (when configuring the 3DUse build) to point cmake to where you installed LASlib... What is the OS on which you are trying to build ?