cmiVFX: Houdini Fluid Effects For TD's

Fluids are often thought of as just being a surface that is rendered and effects that are applied to this surface, and often these can be treated as independent effects however in this video, I focus on exposing that what makes Houdini unique, that being the ability to create complex scalable particle simulations like splashes and bubbles, where these effects rely on the fluid simulation to introduce complex customizable behavior.

Applying Concepts
When trying to generate fluids, there are a number of secondary effects that are normally added to create the sense of realism. Relying on canned effects can only take you as far as prebuilt methods normally do.
However being a Technical Director, one normally needs to push things further and have an underlying insight into how the technology behind the tools we use work in order to create effects that are realistic but controllable.
This video focuses on exposing how to generate these effects from the ground up by using unconventional methods of taking simulated data out of any fluid simulation and using this in your own custom VOP networks.

Starting At The Begining
I don't aim to cover all the concepts behind generating fluids, however there needs to be a chapter that gives you enough to get you started, specifically starting with generating the data we need for the effects we want to create. So I cover a couple of problems you will run into when generating fluids for the first time. Since it is focused on getting underneath the hood, I refrain from using to many prebuilt techniques and try to reveal how things actually work when sourcing from object within your scene while handling collisions between liquids and other rigid body objects through to tips on handling larger simulations and finally on how to write data out.

Fluid In Fluid Integration
Having the ability to allow your fluid simulation to effect other simulations, and having them interact with each other help generate really realistic effects. Not only do your fluid simulations have the ability to advect other objects but others can effect your fluid simulation simultaneously, both through forces and through collisions.

Dealing With Sign Distance Fields
The heart of the lectures are about working with that data that fluids simulations produce but is often unknown. That being the volume data that fluid store attributes like density, velocity and various others that can be customized. We look into how this data is added and how this data is extracted and most importantly, how we can generate custom VOPs that sample this data and use it in other places.

Integrating Volume Data Into Custom Particle Effects
Finally we take this data from fluids and build up custom particle effects that tightly rely on the fluid simulation.
Solving problems that range from birthing particles inside a volume, faking collisions and attractions through to creating custom pop networks that extract data from the fluid object and behave as is the two elements co-existed and were simulated simultaneously, giving the user the ability to craft effects in layers and ultimately creating believable particle effects.