Heightmaps

There is an article on Gamedev about them. You can use them in a variety of ways.

Typically they are rendered using a limited form of ray-casting. That is, you shoot out an ''line'' from your eye, and when it hits something, you draw what it hits.

That advantage that a heightmap has in this area comes from the fact that no two things can share the same space. So, if you hit something, you figure out the height and how this relates to the screen, and then adjust the angle of the ''line'' your shooting out so that it just overshoots the current height.

You should really read an article on it, because I can''t explain it properly here.


ie:
/
3
o ---- 23 2
12312
abcde

a would be rendered from the bottom of the screen up 1 unit (plus perspective).
b would be rendered where a left off.
c would be rendered where b left off.
d would be skipped, because it''s lowerer than c.
e is the same as d.


Best of luck
Will

You can find a fairly simple example of how to use a heightmap in the billboard-sample from the SDK.

Thanks for the quick responses!

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Bad Monkey Productions

[edited by - shakazed on March 7, 2003 4:54:11 AM]

If ya find a better example please post it, Im interested in the same subject.

www.gametutorials.com
has a great height map tutorial

Another term for heightmaping is Voxel ( A pixel with volume). Search google.

I''m in the process of trying to learn the same thing. My sources are as follows:

I came across a book which has apparently just been released called 3D Terrain Programming by Trent Polack. I''m about 30 pages into it and so far have been very impressed. It definitely would have saved me some time if I''d had it a week ago. I would recommend reading it first, then reading some of the more advanced whitepapers and case studies on the subject. These can be a little overwhelming without a good foundation on the basics.

Whitepapers and other resources can be found here:

http://www.vterrain.org/LOD/Papers/index.html

Also, gameinstitute.com has a class on the subject. Realtime 3d Rendering of Terrains (or something to that effect). It''s a 2 section course and each section is $65.00. I''m currently taking the 1st section and it has been helpful. I could have probably done without it (espeically with the help of the book above), but the course materials have been very useful and some decent demo code is provided as part of the course.

Heightmaps aren''t only used for voxel-terrain, you can just aswell generate triangles using the heightmap, which is what most games does today.

--
MFC is sorta like the swedish police... It''''s full of crap, and nothing can communicate with anything else.

Not DirectX related. Moved to Graphics Programming.