If any of the surfaces will not fit in octree, an error message is printed and the program aborts. If no octree is given, a new one is created large enough for all of the surfaces. The -b option allows the user to give a bounding cube for the scene, starting at xmin ymin zmin and having a side length size. If the cube does not contain all of the surfaces, an error results. The -n option specifies the maximum surface set size for each voxel.
Larger numbers result in quicker octree generation, but potentially slower rendering.
The -r option specifies the maximum octree resolution. The default is 1024. The -f option produces a frozen octree containing all the scene information. Normally, only a reference to the scene files is stored in the octree, and changes to those files may invalidate the result. If the input octree is frozen, the output will be also.