wiki:OsgTerrainData

Version 9 (modified by Torben Dannhauer, 13 years ago) (diff)

--

Terrain Data (DEM / Textures)

to use osgVisual, you need a terrain model to visualize. This model can be generated on thy fly (e.g. via osgEarth) or preprocessed with VirtualPlanetBuilder.
This page gives an overview how to obtain digital elevation model (DEM) data and texture data to build such a database.

The following source data could be used:

  • Digital Elevation Data
  • Textures/Imagery/Orthophotos
    • Free global low resolution texture data : Bluemarble Next Generation (NASA)
    • Free local low/medium resolution texture data: Landsat (NASA)
    • Commercial global medium/high resolution texture data: Landsat (atlogis.com, ...)
    • Commercial high resolution national texture data: e.g. Germany (Geocontent), USA (USGS), ...

SRTM-Data

SRTM data with 3 arcs are available for free at

Local high resolution DEM data (mainly based on SRTM)

Tip: Because SRTM data is delivery in many small .zip or tar.gz files, download and unpack it automatically:

wget -r ftp://xftp.jrc.it/pub/srtmV4/tiff/
for zipfile in *.zip;do unzip -o "$zipfile" -d unpacked; done

US texture data

Local High and global resolution Texture and DEM data

To use LANDSAT arial images, read https://zulu.ssc.nasa.gov/mesid/tutorial/LandsatTutorial-V1.html for introduction. LANDSAT datasets are deliverey with up to seven images, each representing a different sensor with different wavelength. Three of this files (sensors for RGB) must be combined for the raw "natural" image.

The image merging is possible with gdal_merge.py (available in FWTools):

gdal_merge.py -o outfile.tif R_sensor.tif  G_sensor.tif B_sensor.tif

National high resolution data

National high resolution data is available from many companies. Germany: GeoContent

compress Data

To shift system load from HDD to CPU, compress all textures lossless with LZW. This will decrease rendering time a lot, because usually the HDD ist the bottleneck.

gdal_translate -co "COMPRESS=LZW" unsw ToDo

Moon Data

To animate earth rising above moon horizon, it could be usefull to model the moon.

http://lunar.arc.nasa.gov/dataviz/datamaps/index.html

Misc data

This website collected data relevant for earth rendering, which includes:

  • Reflectance Maps,
  • Cloud Layers,
  • Bump-maps

http://planetpixelemporium.com/earth.html