Course Overview

Class Description:

This recorded class will explain how to shape vectors into custom velocity fields for use in art directing particles, objects, liquids, and volumes movement. Moving data through different contexts in Houdini is a must-know in creating stellar FX, and controlling that movement even more so. You will learn how to create and control velocity field forces in Houdini and through the power of VEX coding, I will guide you through the core basics of vectors, forces, and velocities. VEX can be a highly technical subject to discuss, but the aim of this class is to make it as easily understandable for artistic and technical minds alike. Each bit of code will be fully explained and questions are highly encouraged.

Learning Outcomes:

Students should leave with a better understanding of how to begin building and implementing their own velocity flows for art directing simulations.

Course curriculum

    1. Files

    1. 1. Introduction

    2. 2. How Is Everything Organized

    3. 3. Vector Definition

    4. 4. Magnitude Definition

    5. 5. Quick VEX Intro

    6. 6. Sim At SOP vs DOP Level

    7. 7. Difference Between Force and Velocity

    8. 8. Velocity Field Definition

    1. 1. Initialize

    2. 2. Visualizer Setup

    3. 3. Finish

    4. 4. Simulation Settings

    1. 1. Geo Setup

    2. 2. Point Wrangle Initialize

    3. 3. Finishing the Wrangle

    4. 4. Q&A: Using pointattrib() over point()

    5. 5. Q&A: Using points from volume node

    1. 1. Initial Geo Setup

    2. 2. Velocity Setup 1 (Trail)

    3. 3. Velocity Setup 2 (VEX)

    4. 4. Finish Setup

    1. 1. Initial Setup

    2. 2. Point VOP Setup

    3. 3. Finish

About this course

  • $70.00
  • 79 lessons
  • 7.5 hours of video content

Course Teaser

Session 1

Fundamental Setups

Creating basic setups: we will focus on the core terminology, their similarities and their differences in the context of Houdini. I will also explain a variety of ways to generate a velocity field volume at the SOP level that can be used to advect your simulation.
  1. Understanding Vectors, Forces, and Velocities meaning.
  2. Basic Builds (POP, RBD, FLIP, and Volume examples)
  3. Simple Vector
  4. Targeted Vector
  5. Motion-Based Vector
  6. Noise Based Vector
  7. Curve Based Vector
  8. Object-Based Vector

Session 2

Advanced Setups

Combining and varying, we will step it up a notch and introduce some controlled variance into our velocity field. Then finally we push things even further by removing the velocity field altogether and directly controlling the velocity force at the DOP level.
  1. Mixing Forces (POP, RBD, FLIP, and SMOKE examples)
  2. Variance Over Length
  3. Suction Vortex
  4. Push/Pull Forces (SOP Solver in SIM)
  5. POP Push/Pull Forces
  6. RBD Push/Pull Forces
  7. FLIP Push/Pull Forces
  8. SMOKE Push/Pull Forces


David Torno

Visual Effects Professional

David Torno is a self-taught visual effects professional with a passion for the technical and educational side of VFX. Since beginning his career in 2000, he has worked on films, commercials, music videos, and large-scale multimedia projects. In 2008 he started sharing his wealth of knowledge with other creatives through video tutorials, project templates, and utility scripts. In recent years David has focused mostly on 3D volumetric and particle animation. Through the consolidation of his life's work under the Fendra Fx name, David continues to create helpful tools, and informative training videos for the creative community.



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Students may request a refund up to 1 day before the start of the course. Students may also withdraw from Multi-Session Courses at any time and are entitled to a pro-rated refund. The withdrawal date must be 1 day before the next class they intend to drop.

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“Hey everyone! Super happy to finally have the time to dive into this class - I've been eyeing it for such a long time now Almost done with Session one, can't wait to apply it to my projects! @David Torno | Educator your way of breaking down all of these different principles is really pleasant.”

Danial Ghods

“Hey David! I just jumped in the velocity course! I love how you did the presentation inside Houdini! I can't wait to use this knowledge with the cloth !!”

Lisa Clyne (Smashed Pixel)

“GM! To start this week in a colorful way, here's something pretty and superficial, just the way I like my experiments to be. This one I made while going through most excellent course on velocity fields from @HoudiniSchool.”


“Thank you so much for the share @HoudiniSchool!! I strongly recommend that anyone wanting to get better at Houdini sign up for the classes. Just perfect and a very friendly learning environment! ☺️”

Jacktone Okore

See you in Class!