VFX - Breakdown

Visual Effects (or VFX) in 3D are often sets visuals that cannot easily be modeled or otherwise created with more traditional 3D methods. Instead, they are frequently calculated frame-by-frame, generally using the knowledge of the prior frame to determine the current frame.

If you're familiar with 2D Animation practices, then some things might immediately come to mind, such as animating fire, water, or smoke.

However, 3D VFX can include other things, such as:

• Buildings Breaking

• Objects Breaking

• Cloth Simulation

• Hair simulation

• Crowd Simulation

• Vine/Plant Growth

• Most "Procedural" Content

At its core, almost everything VFx are based on particles. Not all of uses particles, but a good majority tends to.

Particles tend to consist of many small sphere entities, each one having some amount of gravity and physics enacted upon it.

Each particle by itself doesn't necessarily do a lot. However, when many, many individual particles act together, it results in an increasingly realistic simulation of the water/fire/etc.

For more details on how particles work, see the below Pixar in a Box videos.

Pixar in a Box | Effects | A good, visual introduction to how VFX works.

Be wary when using VFX.

VFX are fun, and create neat things. However, since these often simulate complicated real-life physics, with complex mathematics used behind the scenes, these can get very expensive to compute.

Less particles means it will be easier to compute, but the end result will be much less realistic.

On the note of "complex mathematics", don't worry! Unless you're part of the team developing the 3D software, OR you're doing something really crazy and unique, you often don't need to know complicated math in order to use VFX. It's already done for you!

We only bring it up because it's good to be aware of what's going on behind the scenes, so you understand why your software might be running slow and why.

For most VFX work, the software will give artists simplified controls to control the very complex and expensive math being done in the background.

One last tip: When working with particle-based VFX, we can use less particles to get a rough idea of the initial effect. It will be much faster to get going that way.

Then we can add more particles and deal with the "heavy lifting" once the scene is generally finalized, and we want to render the final product.