public void AllInvalid()
{
for (int index1 = 0; index1 < (int)_size.X; ++index1)
{
for (int index2 = 0; index2 < (int)_size.Y; ++index2)
{
if (_data[index1, index2] != 0)
_data[index1, index2] = 2;
}
}
}
}