def init_cells(direction_map):
cells = []
nx, ny = direction_map.shape
for i in xrange(nx):
cells.append([])
for j in xrange(ny):
theCell = Cell()
theCell.x = i
theCell.y = j
cells[-1].append(Cell())
for i in xrange(nx):
for j in xrange(ny):
i_next, j_next = direction_and_value.to_indices(i, j, direction_map[i,j])
if i_next < 0 or j_next < 0 or i_next == nx or j_next == ny:
nextCell = None
else:
nextCell = cells[i_next][j_next]
cells[i][j].set_next(nextCell)
return cells
