I'm going to hang a six foot swing on my screened in porch and I think I have a problem. The roof of the porch is slanted, and the 4x8 beam that I'll be hanging the swing under and from is also slanted. On the left side of the swing it's 4 feet up to the beam, and on the right side it would be 6 feet up to the beam I'm going to hang the swing from.

If I hang it this way, the swing will not swing in a straight line and will swing crooked. Trust me I know from hanging my kids swing from a crooked branch in the yard!

Any idea how I can hang the swing from this slanted beam so that it can swing in a straight line?? Your help would be appreciated. Thanks,