Future Platform Support

According to the webpage, DIRSIG4 is currently only supporting Solaris/SPARC 2.9+ and Linux/x86 2.4 kernels.

The next set of releases (dirsig-3.6.5 and dirsig-4.0.7) will come with experimental support for the x86-64 platform. Internally, we have a cluster of Athlon64 machines running Fedora Core 5. The added registers on the 64-bit x86 architecture give a significant speed boost over the 32-bit counterpart.

The biggest issue with supporting new platforms is packaging the end product. Solaris is a particular pain because users are poor at keeping their installations up to date. There are still people out there using Solaris 8 when the current OS version is Solaris 10.

Another issue is which version of LAM MPI to use for the Linux builds. The key contenders are 7.0.6 and 7.1.2. Most of our userbase tend to have older OS setups, so we will probably use the former.

Comments

LIDAR Point Cloud Visualization

A common question we get asked is how to visualize the point cloud data produced by either the Linear-mode or Geiger-mode LIDAR simulations. First, you should remember that the point cloud files produced by the "APD Processor" are simple ASCII/text files. Each line is the entry for a single return or "point" in the point cloud, including the point location and some attributes that vary depending on whether you modeled a Linear-mode or Geiger-mode system. For a Linear-mode system, a point cloud file will generally look like the example below: 12.7388 -45.3612 -0.0256 5.0290 0 0 0 0 12.8169 -45.3612 -0.0264 4.8362 0 1 0 0 12.8950 -45.3612 -0.0271 4.8362 0 2 0 0 ... 32.4008 -25.5446 10.5945 4.6783 0 65533 0 0 32.4781 -25.5446 10.5953 5.8959 0 65534 0 0 32.5360 -25.5640 12.5408 5.9185 0 65535 0 0 The first three columns are the X/Y/Z location of the point return. The 4th column is the intensity (in photons). Since Linear mode can support multiple returns per pulse, t...

Viewing and Importing DIRSIG Output Images

We are often asked what programs can view DIRSIG's image outputs and how to import the raw DIRSIG image data files into other tools for further processing. For basic image viewing, DIRSIG-4.4.0 now includes a very simple viewing tool. Launch it from the main simulation editor window by selecting the "Start image viewer" option from the "Tools" menu. If you run your simulation from the GUI simulation editor, new image files are automatically added to the list in the image viewer as they are generated. If you want to manually add files to the list, simply select the "Open" item from the "File" menu or the toolbar. Here is a screenshot of the main image viewer window. The top part contains the list of currently opened files and the bands within those image files. To view a single band as a gray-scale image, choose "Single Band Display" from the combo box and then click on the image band that you want. Finally, click "Load Band...

DIRSIG5: An introduction, a timeline and a paper

Although we will be devoting more time to this topic in the blog, many of you are aware that the next generation version of DIRSIG (aka DIRSIG5) has been under development for the past 2 years. This was a ground-up, restart from zero, etc. effort that establishes the DIRSIG modeling toolkit for the next decade. New core, new approach Although we have developed a compatibility layer to allow existing DIRSIG4 simulations to run, the DIRSIG5 model is radically different under the hood. The lightweight and highly optimized radiometry core uses a different numerical radiometry (light transport) approach than we used in DIRSIG4. In addition to being faster (less work to get an accurate answer) this algorithm is far better suited for parallelization. As a result, we have implemented micro-scale parallelization (multi-threading on multi-core CPUs) from the start and work on macro-scale parallelization (MPI distribution on cluster-style computing) is getting underway. This radiometry core al...

DIRSIG

Search This Blog