wavefront object terrains

OpenGL OpenGL: Basic Coding
1

Hi,

I was just wondering if anyone had any wavefront object terrains (flat land, mountains, desert, whatever), or knew of any links to find some? For whatever reason they’re impossible to find on google. Thanks…

GaMEFRo

2

you mean .obj terrain objects ?

actually if you mean it is not a very good solution, the way i do it is the make picture and then set the terrain’s height to the image’s brightness. It’s because then you’ll have objects stored well to process and select which to draw and which not to.
For other details:

http://www.swiftless.cdadc.com/tutorials/opengl/heightmap.html

and also a in book Opengl Game prorgramming.

3

Well, using general 3D formats for terrain is not a bad thing - you are free to create shapes that could be difficult to achieve with heightmaps.
If you split such object into smaller sectors, then you only need frustum culling and you’re done.
Beter yet - you can create terrains at different levels of detail and use scene graph.

4

Originally posted by k_szczech:
Well, using general 3D formats for terrain is not a bad thing - you are free to create shapes that could be difficult to achieve with heightmaps.
If you split such object into smaller sectors, then you only need frustum culling and you’re done.
Better yet - you can create terrains at different levels of detail and use scene graph.
Another upside is that you can have your mesh pre optimized where flatter areas have less polygons and other areas have more where needed.
Though one thing is worse when using that method, filesize, though the number of vertics are less you do have to store extra data, like normals and texture coordinates, in theory each vertex will take 8-32 times as much data compared to regular texture based heightfields (but it will still load a bit faster since there is no data processing done for it).

And on a brighter note, it doesn’t have to look bad just because you use a texture based heightmap, just run around Hellfire peninsula in WoW:BC for a while and you will see what i am talking about, texturing is key to a good height map.

5

texturing is key to a good height map
Yep. This is what I get with heightmaps:
http://ks-media.ehost.pl/images/landscape/03.jpg
http://ks-media.ehost.pl/images/landscape/04.jpg

http://ks-media.ehost.pl/images/landscape/05.jpg

Ok, but we’re running off-topic here.
To get an .obj file with terrain I would suggest to make a simple converter from heightmap to .obj - it shouldn’t be too difficult to create.
Now we just need a heightmap. Go to www.planetside.co.uk and download terragen - it’s free for personal use and you can generate heightmaps very easily with it.
I’m actually using Paint Shop Pro to draw my heightmaps.