The idea for the power generation plant came from the thought that alien planets could have almost any type of plants. So I figured why not have a planet where trees generate electricity that is harvested by machines? The original idea was to have the plants grow in a laboratory-like environment, but I later changed it to a forest (Fig.01).
Anyway, once I had finished the basic concept in Photoshop I started to model it in 3ds Max. I quickly realized that modeling the tree in Max wouldn't be the best idea as I wanted to create quite a few variations of the main tree and wanted to keep the structure as procedural or live as possible so that it would be easier to make changes later. So I finally decided to model the entire forest procedurally in Houdini.
Here is a rough breakdown of the modeling process for the tree in Houdini:
I created a central curve. The idea was to create a base curve and have the entire tree twist itself around that curve. In order to do that I started by making a line. Using a Point SOP and basic Sin and Cos functions converted it into a helix (Fig.02).
For the vines I followed the same process except with a larger radius (Fig.03).
I then used a Wiredeform SOP to deform both these lines around the central curve (Fig.04).
Using a Vopsop I added some noise-based deformation on the curves.
To create a tapering effect I created a red gradient going from the base to the top point of the curves. Using a Polywire SOP, I used to red color to drive the width of the curves and made three copies. This got me the central trunk of the tree (Fig.05).
For the vines I followed the same method, but kept the polywire thinner and made more copies but kept the angle randomly switching between 0-360 degrees (Fig.06).