I've been looking around and i haven't quite found a way to do this yet without going through a lot of trouble.. I'm trying to curve a plane. To be clear,i'm not trying to do this: What is the fastest way to create a curved plane?
What i'm trying to do, is this:

What i want to do is put inward curves on all 4 edges, and possibly a curve on 'top' of the plane as well. I managed to get one inwards curve by using the Curve Modifier, but i haven't managed to get multiple curves at once by using this. also, it messes up the rest of the plane when i do that. So, is there a way to do this?
P.S. For anyone who wants to know, i'm trying to make a shadesail for a 3D house project. The last time i did a shadesail, I made it manually and it took AGES so i'm just trying to find a way around this problem. Thanks :)












