How to properly make terrain?

What I would always do is:

-Add a plane, subdivide it a bit
-Raise or lower some faces until satisfied

Doing this has often led to having some faces not behave like it should, and would cause the player to sink slightly into the ground.
It also made faces change shapes when going in/out of edit mode…

http://www.pasteall.org/blend/30329
Here’s an example.

-Notice how it SINKS into the ground, and
-when going in and out of Edit Mode, how the faces change.

This happens all the time, is there a better way to make terrain?!

Did you make the collision bounds into convex hull?

I hadn’t initially, just went and did that now…


Now it hovers slightly over the map.

Did you click the collision bound box.It must have a check by it.

I use an external heightmap generator, such as geomorph, which can do nice stuff such as various types of erosion.
Then I import it and apply it as the displacement modifier.

Finally, the step you’re interested in is:

  • Apply the decimate modifier with collapse to ~0.95 (you can tweak it and generate LOD) and check … the triangulate button.

I had the same problem a while back. I was able to fix it by triangulating the faces. There are multiple ways of doing this. ctrl+T is an easy way of doing this.

It worked!

Never woulda figured that out on my own,
I rarely use the modifiers!

Thanks a bunch Geoff, that’s been bugging me for years.

EDIT: I only saw your post after I posted my this ^
That methods works too, now I have to pick between the two.

Tris do load quicker, and considering there will be many faces for the terrain, would I be better off
doing what Kendrick said?

By checking the triangulate button on the decimate modifier, you do triangulate the mesh, so they are equivalent, except that the decimate modifier will also remove any nearly-flat surfaces and join them into a single face.

Be aware, the GPU always creates triangles. You only “save” faces while modelling. This is btw. the source of your problems.

A) you created distorted quads (they are not flat)
B) the renderer and the physics engine triangulate the quads with different results (there are always two exclusive solutions to triangluate a rectangle)

Solution: Avoid distorted quads. If you can’t - excitedly triangulate the distorted quads by yourself.

Oh… that it does, how embarrassing.

@Monster: It’d be a little tough to avoid them, when you say “By yourself”, you mean triangulating them manually (via the Knife tool)
or just doing what was mentioned above?

Either way. As long as the result is a mesh that does not need to be triangulated by the engines it will be fine.

Btw. You can simply press <ctrl+t> :wink: