def construct_tree(d):
items = []
for idx in d:
x = X[self.index_map == idx]
y = Y[self.index_map == idx]
z = Z[self.index_map == idx]
f = self.data[self.index_map == idx]
if type(d[idx]) == tuple:
sub_items = construct_tree(d[idx][0])
b = Branch(sub_items, x[0], y[0], z[0], f[0], id=idx)
for i in range(1, len(x)):
b.add_point(x[i], y[i], z[i], f[i])
items.append(b)
else:
l = Leaf(x[0], y[0], z[0], f[0], id=idx)
for i in range(1, len(x)):
l.add_point(x[i], y[i], z[i], f[i])
items.append(l)
return items
