Ivy Generator is an open-source graphical interface for generating ivy vine around imported .obj 3D forms.Users can control the growth of the vine with parameters.

The ivy grows from one single root following different forces: a primary growth direction (the weighted average of previous growth directions), a random influence, an adhesion force towards other objects, an up-vector imitating the phototropy of plants, and finally gravity. This simple scheme reveals that the goal was not to provide a biological simulation of growing ivy but rather a simple approach to producing complex and convincing vegetation that adapts to an existing scene. The ivy generator imports and exports obj+mtl files

You can download the application along with the source code here. The gallery is pretty cool, too.