Terragen is a terrain modeling software package that has both a free version and a commercial version available for download. This program has a nice procedural engine for synthesizing realistic terrain relief in a matter of a few minutes. Within Terragen 2 Deep Edition, we created a simple fractal based terrain with a spatial extent of 10km x 10km and exported it to OBJ format via the "micro exporter" contained with the Render node. For the DIRSIG render, we simply created a mid-latitude summer (MODEL=2) and 23km aerosol model (IHAZE=1) MODTRAN based atmosphere and attributed the terrain with a 30% spectrally flat albedo. For a little sizzle, we also added a simple rectangular box and attributed with the fresnel optical property of water (n = 1.33, k=0.0). Additionally, it should be noted that we had to manually rotate the OBJ file (within Blender and re-saved to the same file) by 90 degrees since Terragen uses the +Y is up convention while DIRSIG uses the +z is up con
A blog about the Digital Imaging and Remote Sensing Image Generation (DIRSIG) model featuring posts contributed by the developers. This is not a user manual and it is not a training class. But, it is a place to see what the developers are doing and a little about how we do it. So think of this as a place to learn cool tips, tricks, etc.