The base of the animation was constructed from 3 different simulations, each with slight variation in the motion to create visual interest throughout. Using various camera angles in the final animation helped mask what was happening under the hood, and create more appealing and abstract results. The first simulation was a simple noise force applied to the leaves in order to create a natural, flowing motion. The second used animation spheres to act as collision object to create so intersting patterns in the leaves, and the final also used spheres but instead used the velocity of the movement to drive the simulation so that the results looked more organic.
To push the vellum simulation (and the machines) as far as possible, thousands of colliding leaves were used in the process. This created it’s own problems in that geometry had to be low enough resolution to keep simulation times realistic. In the end simulation was done on low resolution geometry created with the remesh node, and the high resolution geometry with UV’s were used as a post-process using the point deform node. This also helped fixed interesections and collision issues that came with simulating such a high number of geometry.
A big contributing factor to the overlook and additional interst to the animation was the colour variation throughout. The power of Houdini and Vellum allows for harnassing attributes provided by the simulation to create extra visual appeal – in this instance, the variation in blue hues throughout was created using the Velocity attribute to calculate the speed of the motion, and driving the colour variation with the resulting colour.
