Varrier Demo Instructions

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I have installed a run script for the Earth demo at

   /DEMO/evl/varrier/bin/RUN_EARTH

The source and data are owned by rlk (that's me), but they are universally readable and executable. I have changed the ownership of the run script to covise.

The Earth demo works just like the Mars demo, and the trigger button engages the navigation. It accesses a LOT more data, so it is much more susceptible to lag during data loading. Make smooth motions and everything will run smoothly.

The RIGHT button resets the view position. The SECOND-to-the-right button toggles monochrome shaded relief (which really shows off the terrain... it's how geologists view terrain data.)

CONTROL-RETURN toggles stereo and mono mode.

Calibration is similar to Electro: CONTROL-TAB engages calibration mode, CONTROL-ARROW keys tweak the tile. One difference: CONTROL-SPACE and CONTROL-BACKSPACE cycle through the tiles. The calibration is automatically stored in the home directory of the current user, so there's no need to worry about updating it by hand.

The data is layered. There are 5 distinct data sets in use:

1) Blue Marble Next Generation (BMNG) is a color map covering the entire Earth with a resolution of 86400x43200 (Yes, that's the same res as the demo on the wall upstairs). That's 10.4GB. It has a spatial resolution of 500m at the equator.

2) Shuttle Radar Topography Mission (SRTM/RAMP2) is a height map of the entire Earth with the same resolution (86400x43200). That's 7GB. It has a vertical resolution of 1 meter.

3) The SRTM/RAMP2 normal map allows for per-pixel illumination at that resolution, consuming another 10.4GB.

4) The National Elevation Database (NED) is a height map covering all US territory. It has a spatial resolution of 30m. It is not rectangular, so it's bounds cannot be easily stated, though it is 34GB of information. It too has a vertical resolution of 1 meter.

5) The NED normal map allows per-pixel illumination and shaded relief of US territory. It consumes 51GB of storage.

So, in the current state, there is a total of 114GB of raw data. This is mipmapped, which imposes a 33% overhead, giving 150GB of data. This is losslessly compressed to PNG, which reduces it to 38GB of data, spread across 189,582 files.

Let me know if there are questions or comments.