BUG: Fix ugly bug in 3D viz code that was not using the given anatomy.
BUG: Fix ugly bug in 3D viz code that was not using the given anatomy.

alexis-roche/nireg,alexis-roche/nireg,alexis-roche/nipy,alexis-roche/niseg,alexis-roche/register,alexis-roche/register,alexis-roche/niseg,nipy/nireg,alexis-roche/register,bthirion/nipy,arokem/nipy,arokem/nipy,arokem/nipy,alexis-roche/nipy,nipy/nipy-labs,nipy/nireg,alexis-roche/nipy,bthirion/nipy,nipy/nipy-labs,bthirion/nipy,alexis-roche/nipy,bthirion/nipy,arokem/nipy