UDK Notes - Landscapes, Terrains, Islands And Backgrounds

Landscape objects are great because they can be sculpted right in UDK and will automatically have accurate collision geometry and levels of detail.  It's quite easy to build an environment based around a landscape object.

Remember that a landscape is just a base.  You will create many detail objects (rocks, cliffs, trees, etc) to decorate the landscape with.

If you have an existing scene you can bring in a model from Maya to use as reference and model your landscape to match it.
You can also export your scene, including the landscape, to Maya.

You can use other software to generate landscape but this can be fairly complicated.  Since the sculpting tools in UDK are good, we recommend you just sculpt the landscape in UDK.

For distant background objects, you can just use static mesh objects. Either model them at a large size or set the draw scale large. (You can get away with extreme changes in draw scale here because there are no collisions or other calculations needed for far off background objects.)

A Example Of Using A Landscape For A Small Island

For an explorable but fairly small scale island, the following settings work well

Put the sky, ocean, facades, and landscape in different layers in UDK. (Window > Browser > Layers,  or the layers tab in the content browser.)


  Make a polygon cylinder

  Radius: 512
  Height: 512

  Subdivisions Axis: 32
  Subdivisions Caps: 64
  Delete the sides and the bottom

  Move all the verticies down 256 (so their y location is zero)

Sky sphere

  Make a polygon sphere

  Radius: 512

  Subdivisions Axis: 32
  Subdivisions Height: 64 (delete most edges after)

  Remove extra edges
    keep the ones near the top
    get rid of every second horizontal row
  Invert the normals (select all faces in Maya, Normals > Reverse)

  Load your texture into the incandesence in Maya
  Export the scene as a FBX file.
  In UDK, set the drawscale of the sphere and water to 16 in order to have a full size of 16384
  ( 512 original size * 16 draw scale * 2 )
     2 comes from  2 radius/1 diameter

  Create a material for the sky sphere

  It should be roughly as follows:


  Apply the material to the sky sphere

  Change the properties of the static mesh sky sphere
  (Double click the skybox mesh in the scene)
    Static Mesh Actor
      Static Mesh Component
        Override Lightmap Res:  on
        Override Lightmap Res:  0   (zero, this means vertex lit or no light)
        Cast Shadows: off

Landscape For Island

Background Objects Such As Distant Islands

Paint an island in photoshop on a transparent layer
Create a targa with an alpha channel (save as 32bits)

To use an alpha channel for transparency in UDK:
  set the material type from BLEND_Opaque to BLEND_Mask
  plug the alpha of the texture to the materials opacity mask

Teaching3D is a creation of Joe Crawford