Footprinted Objects

Footprinting is a system that provides the engine with cell-based information for static objects, such as buildings and bridges.  To create a footprinted object, the geometry should include a grid called "SP-0" (shadow plane zero) at the same size as the terrain cells (8m). This is the primary grid and provides most of the data used in footprinting.  Additionally, each footprint can contain another grid called "SP-1". This grid is optional, and provides a "terrain overlay" heightfield on which units can travel (e.g.. for a bridge), and on which shadows are cast.  

Building a footprinted model

Build a grid called "SP-0" the size of model's footprint. The spacing between each vert should match the cell size (8m).
The grid's verts should never be moved in the x/z - snap the object geometry to the grid, not the other way around.
Build an optional grid "SP-1".  The model's geometry must match it exactly whereever units will move or shadows will be cast.
Both grids must be complete (no verts can be missing from the grid)  and the same size (identical in the x/z).
Both grids should be children of the model's root object.
After the art is complete, additional information can be edited in the studio using the footprint editor. By default, each cell is set to be hidden and zipping.  On a per cell (or per vertex) basis, each of the following attributes can be changed:
Hide a terrain cell (turn off its display so it can be replaced by geometry).
Set a cell to base terrain type.
Use second layer (should a cell use the SP-1 layer for floor finding).
Zip a vertex to the SP-0 layer (height of cell is set from the primary grid).
Use grid color (the color on the grid is applied to the terrain).
Path searching directions (specify that an object can walk up a ramp, but not off the side).