I have been experimenting with the new terrain, trying to work out some of the issues.
The default “size” of a terrain in World Machine is 8 kilometers square. But this is completely relative. The main output from World Machine is a heightmap (or optional OBJ mesh) and colour textures.
When I open the OBJ file in LightWave, it is only 1 meter square. So I have been scaling it up by a factor of 8,000 so that it “matches” World Machine. This had the unintended effect of diluting the normal and bump map effects that I was trying to introduce.
This time, I only scaled up the mesh to be 100 meters per side. This brought out the normal and bump effects. It also revealed another issue – the normal map should be producing erosion cuts into the rock. However, these are looking like veins on a steroid-abusing power lifter’s arms!
I think I know the cause though. The OBJ file is using the Z-axis as “up.” Carrara did the same thing. In LightWave the Y-axis is up and I have rotated the mesh to fit LightWave. So I need to adjust the normal map, either in LightWave or figure how to adjust it in World Machine. That will be what I experiment with tonight.
The sky is darker than before. I previously adjusted the brightness in the LightWave Image World tool. This caused too much light from the HDRI and I had to reduce the effect of the global illumination. This is not the best solution. I now know that the HDRI gamma needs to be changed.
So I am slowly getting there. Pretty soon I should be able to create good looking terrains on a regular basis.