def compute_faces(ipl, key):
faces = IPL(data={key: ipl[key]})
shp = faces[key].shape
ipl.logging('Computing faces ...')
faces.get_faces_with_neighbors(keys=key, rtrntype=IPL)
# startpoints = ipl['faces', keys[0]].keys()
additionalinfo = IPL()
startpoints = IPL(data={'xyf': shp[2],
'xyb': shp[2],
'xzf': shp[1],
'xzb': shp[1],
'yzf': shp[0],
'yzb': shp[0]})
areas = IPL(data={'xyf': np.s_[shp[2]:shp[2] + shp[0], shp[2]:shp[2] + shp[1]],
'xyb': np.s_[shp[2]:shp[2] + shp[0], shp[2]:shp[2] + shp[1]],
'xzf': np.s_[shp[1]:shp[1] + shp[0], shp[1]:shp[1] + shp[2]],
'xzb': np.s_[shp[1]:shp[1] + shp[0], shp[1]:shp[1] + shp[2]],
'yzf': np.s_[shp[0]:shp[0] + shp[1], shp[0]:shp[0] + shp[2]],
'yzb': np.s_[shp[0]:shp[0] + shp[1], shp[0]:shp[0] + shp[2]]})
additionalinfo[key, 'startpoints'] = startpoints
additionalinfo[key, 'areas'] = areas
return (faces, additionalinfo)
