Render Distance Fog

[ataulien]

In Gothic, distance fog serves as a way to limit the draw distance. Also it looks nicer:

The fog itself is just simple linear fog calculated by taking the distance of the camera position to the currently shaded vertex. The distance where the fog should start (near) and where it should end (far) are already calculated here:

https://github.com/REGoth-project/REGoth-bs/blob/5ce1261fd48b55d02cc7ff734e67e56f13114d61/src/components/Sky.cpp#L46-L50

It seems like bsf does not support Fog at the moment, and even if it did we'd most likely have to implement it into our custom shaders anyways: https://github.com/REGoth-project/REGoth-bs/blob/master/content/shaders/World.bsl

[ataulien]

Looks like bsf does not support global shader variables just yet, so we would have to assign the distances and color to each material separately. That is highly inefficient, we need to get around that somehow.