After some experimentation I’ve decided that the best way to create the terrain for the HUD is to create it from scratch in World Machine. I can generate a mesh as a wavefront object that I can open in Photoshop. I don’t know whether Photoshop can handle either tri or quad polygons but World Machine can export meshes of both types so I should be safe either way.
Once in Photoshop I can apply a simple texture and then I have the flexibility of being able to rotate to any angle in order to suit my composition. It has the added bonus of cutting down on render times too.
The images I’ve attached are of the terrain I’ve built for my project. The image shows the devices I’ve connected in order to create the terrain. I’ve attached them to a heightmap output device in this instance so you you can see a clearer thumbnail of the terrain. The mesh output device is just above.
You can see a far clearer snapshot of my terrain in the 2nd image.