Lakes and Tarns
In a 3D model of the Lake District a good representation of the water bodies is always going to be important. This is quite tricky for the Overview level as it needs to be something that looks good both from a distance and closer up.
In the 3D terrain model the Lakes aren't 100% flat and so this was fixed by creating geometry polygons of the right shape and overlaying these onto the terrain.
Lake Polygon - Red Tarn
A fairly simple texture was found to provide good performance and looks reasonably realistic. However, one issue encountered was "z-fighting" between these textured polygons and the underlying terrain. This is where the graphics system can't work out which surface to show when they are relatively close together, resulting in annoying flickering. This was resolved by cutting away the terrain below these polygons.
Terrain hole below polygon
Finally labelling was added to identify all Lakes and Tarns.
Final Representation of Red Tarn
The waterbodies can now all be seen and identified clearly.