Another test on this terrain set....
Well you've heard me rant about canopy and landcover maps.. and I've posted samples of tree distribution using the canopy map. The landcover map is not immediately useful but it does contain some very useful data (if only low res). What you do with it is limited only by your imagination. Here's the result of my morning train ride
I selected the two main colours from the map that represent concrete/pavement and constructed a mask to simulate artificial lights (cities and highways). Quick and crude... but interesting all the same. Apart from tweaking the colour/luminosity, I'd also increase the contrast in the mask (only two colours, but separating them more would make it look more realistic) add a noise function to the mask to break it up a bit more. You could also add some extra glow by creating a second luminous layer with less luminosity using a scaled down version of the mask image. Anti-aliasing should blur the edges enough to create the soft spread.
As a hack I think it works quite well and it's easier to set up for elevation data than the global city lights image (and possibly higher res?).
The view is from the NW corner of the 410km terrain looking back towards Rainier etc...
(canopy and landcover masks are now added to the url above... I'll set up a proper page tonight with the extra info)
