First create the terrain you want to export in WorldCreator… Done? Good! Now, the next step.
You should have something like this:
First we want to make sure the "height" and "width" of the terrain matches something we can work with.
In WC set width to match the terrain size (that is match the size of the image), and scale down the height proportionally so that it matches.
E.g. if the width was 12000 and height 2500, and you are exporting a terrain with a resolution of 2048 then it would be:
First you want to make sure that the output will have the correct color, I'm using the shader to color my terrain so I will select the "Use Shader" option, but you should pick the one that suits you.
Now, what you want to do is turn off the relief, so you can get a clean output as T3D will handle the shadowing of the terrain, so make sure "No Relief" is selected:
Now you should export the diffuse texture:
And finally export the heightmap, use the 16bit tiff output, I know T3D doesn't like tiff very much, but we want our heightmap to be in 16bit.
Now we want our heightmap to be in a format that we like, but finding an image converter that preserves the 16-bit heightmap is very difficult. So I cooked one together using imagemagick. You can download the converter here: WC2T3D.zip
To use it, simply drag-and-drop the heightmap on top of the .bat file like this:
Now simply follow Import of terrain heightmap tutorial