def addFacesByGrid(faces, grid):
 cellTopLoops = getIndexedCellLoopsFromIndexedGrid(grid)
 for cellTopLoop in cellTopLoops:
  addFacesByConvex(faces, cellTopLoop)

def addFacesByGrid ( faces , grid ) : cellTopLoops = getIndexedCellLoopsFromIndexedGrid ( grid ) for cellTopLoop in cellTopLoops : addFacesByConvex ( faces , cellTopLoop )
add faces from grid .