Dynamic Relief Mapping

EarthBrowser 3.0 is starting to shape up nicely. I've created a normal map generator using a Sobel filter and SRTM data. Normal maps are just a texture respresenting compressed normal directions and they enable one to create the illusion of very detailed geometry with the help of hardware accelerated shaders.


Africa Relief


Asia Relief


Using the mosaic and raster classes that I described in my previous post, I generate a normal map in the gnomonic projection and put that together with the texture map and a wgs84 ellipsoid and it is starting to look pretty nice. The great thing about it is the shadows move where they should when the light source moves. Someday I'll make a youtube video to demonstrate that effect.