Announcing TerraSTREAM 0.2
We are pleased to announce the immediate release of the second milestone beta release of TerraSTREAM. TerraSTREAM provides a series of components that perform flow modeling and terrain analysis tasks on very large digital elevation models and works equally well on TIN and grid DEMs. The algorithms used in the libraries have provable efficient performance in the worst case, even on very large terrains that do not fit in the main memory of the computer. TerraSTREAM 0.2 comes with direct GRASS and ArcGIS support as well as a simple standalone graphical user interface and powerful command line tools that can be used alone or integrated into most GIS environments by scripting. For more information about this release and for contact information, visit http://madalgo.au.dk/Trac-TerraSTREAM/.
Major changes to TerraSTREAM since the 0.1 release include:
- A new native ArcGIS 9.2 raster driver ensures that ArcGIS rasters are imported properly with correct NODATA and cell type interpretations.
- The TerraSTREAM GDAL raster driver now uses GDAL version 1.5 which provide support for a very wide range of raster types.
- The command line tools have been greatly enhanced and now have very flexible input/output options. For instance grids can now be read using the GDAL driver and output using the ArcGIS driver.
- A new separate frontend has been added to compute the LS-factor (the LS factor is an erosion estimation, we refer to external documentation for more information)
- TerraSTREAM now includes a complete set native GRASS modules that work natively with GRASS rasters (using a native GRASS raster driver) and include supports for the GRASS graphical user interface.
- A ArcGIS 9.2 Toolbox has been created with tools for each individual module. Using these tools an ArcGIS user can construct elaborate pipelines using native tools in ArcGIS.
- Communication of bugs and feature requests to the TerraSTREAM developers are now organized and bugs can be easily submitted using the public TRAC system at http://madalgo.au.dk/Trac-TerraSTREAM/ .
Known Bugs and Issues
- The frontends provided for TerraSTREAM 0.2 does not work on TINs. Even though the core components are available for TINs we have not yet developed user-friendly front ends for these since we have not determined what kind of TIN file formats should be supported. If you would like to use TerraSTREAM on your TINs please give use information on the type of file format you use by replying to ticket:8.
- TerraSTREAM does not currently handle terrains with extreme negative elevations, try raising your terrain if the lowest height is less than -9999 units. This is ticket:9.
- If TerraSTREAM crashes when running modules through ArcGIS or the standalone front end, it is not always possible to see the error message that is written to the command line. If the crashing persists users can run the equivalent command from the command line to see the error message. This is ticket:10.
- TerraSTREAM's ArcGIS driver does not currently set the max/min statistics in the generated data sets, thus the user needs to manually bring up the "layers properties" dialog and select the proper stretch factor in the "Symbology" tab.This is ticket:11.
Getting It
TerraSTREAM 0.2 is available from http://madalgo.au.dk/Trac-TerraSTREAM/.
Note that TerraSTREAM is beta grade software. Bug reports and feature requests are very welcome and will hopefully result in more stable and capable future versions of the software.
Cheers, The TerraSTREAM Developers - February 1, 2008.