displaz - A viewer for geospatial point clouds

displaz is a cross platform viewer for displaying lidar point clouds and derived artifacts such as fitted meshes. The interface was originally developed for viewing large airborne laser scans, but also works quite well for point clouds acquired using terrestrial lidar and other sources such as bathymetric sonar.

The goal is to provide a flexible and programmable technical tool for exploring large lidar point data sets and derived geometry.

• Open point clouds up to the size of main memory. Performance remains interactive as the number of points becomes too large to draw in a single frame.
• Create custom point visualizations. The OpenGL shader can be edited interactively. In the shader program, you automatically have access to any per-point attributes defined in the input file. Shader parameters are connected to user-defined GUI controls.
• Plot interactively from your favourite programming language. Displaz IPC lets you script the interface from the command line. Experimental language bindings are available for C++, python, julia and Matlab.

User guide

See the user guide for usage examples and instructions.

Installation

Binary installer packages for windows are provided on the releases page. For linux, it should be fairly easy to build it yourself by following the instructions below.

Building

Linux

Install dependencies using your package manager. Here's a handy list of dependencies for several distributions:

# Ubuntu >= 14.04 (and probably other debian-based distributions)
sudo apt-get install git g++ cmake qt5-default python-docutils

# Mint
sudo apt-get install git g++ cmake qt5-default libqt5opengl5-dev python-docutils

# Older ubuntu (qt4 based - add cmake flag -DDISPLAZ_USE_QT4=TRUE)
sudo apt-get install git g++ cmake libqt4-dev libqt4-opengl-dev python-docutils

# Fedora 23
sudo yum install git gcc-c++ make patch cmake qt5-qtbase-devel python-docutils

# OpenSuse
sudo zypper install git gcc-c++ libqt5-qtbase-devel glu-devel python-docutils

The following commands may be used to build displaz on linux:

# Get the source code
git clone https://github.com/c42f/displaz.git
cd displaz

# Build LASlib and ilmbase
mkdir build_external
cd build_external
cmake ../thirdparty/external
make -j4
cd ..

# Build displaz
mkdir build
cd build
cmake ..
make -j4

# Install into CMAKE_INSTALL_PREFIX=/usr/local
sudo make install

Windows x64

The windows releases are built using the Visual Studio 2013 x64 command prompt. To install the dependencies on windows, manually download and install the following tools:

• cmake
• msysgit
• qt5 (ensure you get the correct version for your compiler)
• nsis (only required for installable package creation)

The release builds of displaz itself use nmake Makefiles, as generated by cmake. First, clone the repository using the msysgit command line:

# Get the source code
git clone https://github.com/c42f/displaz.git

Next, in the x64 cross tools command prompt:

rem Build LASlib and ilmbase
cd displaz
mkdir build_external
cd build_external
cmake -G "NMake Makefiles" -D CMAKE_BUILD_TYPE=Release ..\thirdparty\external
nmake
cd ..

rem Build displaz.
rem Assumes that Qt has been installed into C:\Qt\Qt5.5.1\5.5\msvc2013_64
mkdir build
cd build
cmake -G "NMake Makefiles" ^
    -D CMAKE_PREFIX_PATH=C:\Qt\Qt5.5.1\5.5\msvc2013_64 ^
    -D CMAKE_INSTALL_PREFIX:PATH=dist ^
    ..
nmake

rem Optionally, create the installer package
nmake package

OSX

TODO - for the moment see the generic build instructions below.

Generic build

To build displaz, install the following tools:

• cmake >= 2.8.8
• Python docutils (optional - required to build the html documentation)

Displaz also depends on several libraries. For simplicity, the smaller dependencies are bundled in the thirdparty directory. There's also an automated download/build system for some of the larger ones (LASlib and ilmbase) available at thirdparty/external/CMakeLists.txt. However, you will need to install the following manually:

• Qt >= 5.0 (qt-4.8 is still semi-supported on linux)
• OpenGL >= 3.2
• ilmbase >= 1.0.1 (You don't need to install this if you're using the automated thirdparty build)

Both the LASlib and IlmBase libraries may be built using the separate third party build system in thirdparty/external/CMakeLists.txt.

Build options

To read the .las and .laz file formats, you'll need one of the following:

• LASlib >= something-recent (known to work with 150406). This is the default because it's reasonably fast and has no additional library dependencies.
• PDAL >= something-recent (known to work with 0.1.0-3668-gff73c08). You may select PDAL by setting the build option DISPLAZ_USE_PDAL=TRUE. Note that building PDAL also requires several libraries including boost, laszip and GDAL.

If you only want to read ply files (for example, to use the scripting language bindings), and don't care about las you may set the build option DISPLAZ_USE_LAS=FALSE.

Supported Systems

displaz is regularly compiled on linux, OSX and windows. It's known to work well with recent NVidia and ATI graphics cards and drivers. Some issues have been observed with Intel integrated graphics and older ATI drivers. If you observe rendering artifacts there's a reasonable chance that your graphics card or drivers are playing dirty tricks

Third party libraries used in displaz

Behind the scenes displaz uses code written by many people. The following third party projects are gratefully acknowledged:

• Qt - http://qt-project.org
• LASLib - http://www.cs.unc.edu/~isenburg/lastools
• PDAL - http://www.pdal.io
• ilmbase - http://www.openexr.com
• rply - http://www.impa.br/~diego/software/rply
• GLEW - http://glew.sourceforge.net/
• Small pieces from OpenImageIO - http://openimageio.org