I'm still at the design stage for my terrain system. A lot of the other work on my flight sim has gone very well, but I've been battering around ideas for the terrain for months now without coming up with a design I like.
I can generate whole planets worth of random terrain no problem, but generating terrain based on real world locations is another whole barrel of triangles.
The input data I already have is in the form of two textures per map, Each map is something like 1000 miles by 1000 miles.
The first texture is a height map. Standard stuff, but at a resolution of 1 pixel = 400 square meters .... not very useful as it stands.
The second has type information in it. it is broken down into 16 terrain types,(4 bits) (water, grass, mountain, etc.) and two bits for roads and railways.
My original plan was to generate a terrain patch for each pixel of the source data, but when you get to above 35,000 feet the number of terrain patches visible becomes ridiculous.
So I'm thinking I am going to need a terrain patch to be about 10 miles square. These will have to be generated from the original data and include a really good CLOD system. Which one is up for debate.
To get the level of detail I need from this is going to be a major challenge. I need to have terrain that looks good when you are stood next to your aircraft, and still looks good at 35,000 feet. Not easy.
So I am looking for guidance from the folks here.
Anybody seen any good papers worth reading?
Anybody got experience writing terrain systems for flight simulators and is willing to share knowledge?
At the moment I have a dozen possible solutions in my head, none of which solve all the problems, all of which solve some of the problems.
I keep starting writing code, and then stopping what I am doing because I realise it won't work.