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Liquid Simulation in Houdini

RBD & FLIP Interactions with Stavros Sofianos


Simulate milk pouring into a bowl of cereal to learn the art of interacting with Rigid Body Dynamic objects and FLIP Fluid Particles. This 3.5-hour workshop by Stavros Sofianos will teach you how to craft a dynamic, art-directable splash effect, filling the bowl with milk and allowing your cereal pieces to float. This tutorial is created for intermediate-level artists with a basic understanding of Houdini.

Stavros begins by creating various layers of cereal and placing them in a simple yet effective way that will allow you to create a pleasing splash interaction later using the FLIP solver. You’ll also explore a Voronoi fracture technique to correctly create proxies that can be used in an RBD simulation to generate the initial state of the cereal in the bowl.

You will discover how to reconnect the proxies back to the original geometries, how to create the emitters for the FLIP simulation, how to master a custom stick field technique so you can control the stickiness of the milk on the bowl and on the cereal, and you’ll learn how to efficiently set up an RBD and FLIP solver together to interact with each other.

This workshop also details how to create our own custom mesh for the FLIP simulation, shows a technique for generating wet maps, and covers Stavros’s shading and rendering techniques using the Arnold renderer.

Project files provided with this workshop include two bowl geometry files (one in Alembic and one in FBX format) and the Houdini file with the setup that Stavros created for this workshop. Links to the models and free assets used are also provided.

Duration: 3h 46m

Format: HD 1920x1080

Stavros Sofianos

Senior FX Artist

Stavros Sofianos has a decade of experience in the production field; to Stavros, creating visual effects is more of a passion than just a job. He’s explored various paths as a CG Artist over the years, using a variety of software in his roles, though he has always been most attracted to creating VFX. He is constantly learning and seeking out new applications and approaches to creating impressive FX and has worked on many TV commercials, TV series, and films as both an in-house Senior FX Artist as well as a freelancer. He works for local studios as well as worldwide clients creating all manner of abstract particle setups, liquid, smoke, fire, and rigid-body simulations. 

Learn more about Stavros and follow his career on LinkedIn.

  • I have collaborated with Stavros on different VFX projects over the years. I have been amazed at the talent that he has, especially when dealing with heavy and complex simulations. He is a remarkable FX artist, blending his technical skills with his artistic flair and point of view in every project.

    - Mike Avramis
    Digital Sculptor

  • I had the pleasure of working with Stavros on various projects. Stavros is a very passionate FX artist with strong technical and artistic skills, and he has always been delivering stunning FX simulations.

    - Tony Zagoraios
    Founder & Art Director at YETI Pictures