Add displacement maps to Descriptions

If you generate primitives on a displaced surface, you can add the same Ptex-based vector displacement map to the Description so that primitives get properly positioned and orientated on the displaced surface. For example, if you instance trees on a landscape mesh shaped by a displacement map, adding the map to the Description ensures the trees generate based on the shape of the mesh.

1. In the XGen Editor, click the Primitives tab.
2. In the Displacement attribute group, turn on Use Vector Displacement for maps.
3. To add the displacement map to the Description, you need to create a map expression. To do this:
   • Click this icon beside Displacement.
   • In the XGen Expression Editor, type a map expression to source the location of your displacement map.

     For example:

     
   • Click Accept.

   The position and orientation of primitives now follow the shape of the displaced surface.