Vertex Detection

This page follows the development of a MEL script that detects the number of vertices in a polygonal model while recording their positions in 3D space. Many interesting effects can be achieved once an artist has control over this data.

The two images above show how polygonal models can be altered at render time for a coil-like effect. Curves are created using the vertices of each model. As expected, the curves pass through every point, but the resulting shape of the coil is pretty random. Automation is possible to give greater control, but it would be difficult to write a procedure that would always create the intended effect for every kind of model.

In addition, even greater problems may occur if a model contains many vertices and is created by "welding" various parts together. The image on the left shows how difficulties may arise if you model half of a character with the intention of mirroring it. I still don't understand exactly why the curves don't continue on to the other half even though the positions of the vertices are correctly recorded.

For all practical purposes, this effect would be pretty useless in a production environment due to the lack of control. However, after learning about this technique, I was determined to find a way to use it for my thesis animation. Any technique that can easily create a greater amount of detail and complexity is a huge advantage for any VFX shot. With this technique, the work is minimal compared to the end result. After all, the 3D models have to be created anyway, right?

The images above show the end result of my script. The image on the right shows the model in Maya's viewport, and the left image shows the same model at render time. Basically, I go through each edge of the model and use the two vertices as endpoints of a curve. I end up with more curves, but the product is much more predictable. I will be using this technique to create two effects for my animation: 1) to create interesting pieces of indoor/outdoor sculptures and 2) to create strutting around windows and buildings. To use this technique most effectively, model topology must be considered from the beginning so that the wires don't overlap. An example of this can be seen in the figure's face, hands, and feet since those areas have a higher polygon count. For future work, I will be placing models inside other models to create even greater complexity.

The strutting procedure can be found here.