Fog and Clipmaps

Made a basic implementation of fog by adding an extra step in the fragment shader to calculate distance to a given fragment and blend a fog color based on that. I have also begun with the implementation of a LOD system for rendering terrain.

Included image shows a hemisphere divided in concentric rings, that get larger as the distance to the camera increases. This is largely based on the paper "Terrain Rendering using Spherical Clipmaps" by Malte Clasen and Hans-Christian Hege.

https://www.researchgate.net/publication/220778464_Terrain_Rendering_using_Spher...