Deform mesh along two curves I'm trying to modify a mesh so that one side gets modified along a curve, and one other side gets modified along another curve.

I tried with vertex groups but it only moves the vertexes in the group, without deforming/moving the rest.

Lattice would be an altenative, I guess, but using curves would make my task easier.

Graphic example as usual:


How do I get the mesh to go all wibbly-wobbly with the bottom face following the bottom curve and the top face following the top curve? 

Update:

This is the desired effect


I got it to work in this real simple example by creating a lattice with u:20,v:1,w:2. Grouped top and bottom vertexes in two different groups. Added a a curve modifier to top group along the top curve and another one to the bottom group along the bottom curve. It works in this easy case, but it's not really versatile.

What if I wanted to do something like this? Where the inner edge loop of the torus follows the inner bezierCircle and the outer edge loop follows the outer bezierCircle, with all other edge loops arranging harmonically
You can achieve kind of that modeling manually.

Select 2 curves, join them, convert to mesh and use Bridge Edge Loops to fill space between them:



Add a loop cut, select it, P to separate selection, and delete new created loop. Enter Edit mode of that separated selection, and extrude it in one of horizontal (in my case) directions:



Join 2 meshes, in Edit mode select outer loops and use again Bridge Edge Loops tool to make faces between them.



I added 2 loopcuts to define another form of the mesh and scaled them by X axis with Pivot set to central loop so to make them not on the default position.
After deleting non-manifold geometry the mesh became like this:



And this is what is done with this technique as for torus:



On the left is the curve I used to define that shape, on the right - the resulting mesh.

It's not ideal and automated, but you may always refine loops' position so it to look in another way.



Advantages

The only one as for me (comparing to Lattice using) - is that you definitely use curves you create to define the shape of the resulting meshes.