A Spotlight on Visual FX

Crowds, Curves, and Spawning, oh my!

This article is for the graphics nerds, the “graph heads” (I think we just made that up?), and the VFX junkies. It gets in the weeds on visual FX updates to Lens Studio: a new plugin, new additions to the Asset Library, and upgrades to Lens Studio’s VFX Graph. Developers can add interest and new dynamics to Lenses with visual effects because we’ve made it easier. You’ll also  hear from Snap AR Engineer, Jennifer Fullerton, who’s passionate about these small, but mighty updates.

Transitions Library Plugin

Creating a surprise experience or revealing something new with visual effects is now easier than ever. This new plugin is a library of transitions that can be searched, selected, and easily added to your Lens project. Search by category, transition name, or keywords. Add VFX to your Lens to transition from one look to another or from one experience to another. Imagine an ocean wave washes over you and you turn into a mermaid, or lightning strikes and you all of a sudden have super powers.

Visual Effects in the Asset Library

New in Lens Studio’s Asset Library are fun and dynamic Visual Effects. For example, VFX Crowds allow you to create a dynamic crowd system capable of interacting with the user and the world. Like these adorable radishes swarming your living room.

Snap AR Engineer, Jennifer Fullerton explains, “Crowds is something that our team has wanted to release forever, so we’re very excited that we can finally send these guys out into the wild. Our goal was to balance flexibility with customizability: anyone can drop these veggies into their project and play with them, right out of the Asset Library. For those really enterprising developers (“graph heads,” I’m talking to you), we left the VFX system open for you to dive in and add your custom behaviors or even change the model using Houdini and Vertex Animation Textures (VAT). There’s lots of ways we could grow this system, so we’re excited to see people use the Crowds and give us their feedback on ways we could improve it.” 

VFX Custom Mesh emission is the ability for the VFX system to create 3D particles, instead of 2D. We also updated the Multi-Mesh VFX, which demonstrates how to emit multiple kinds of geometry in a single VFX system. This upgrade to the VFX system came out last year, and is a critical component to advanced effects like VFX Crowds. Jennifer adds that it’s “a very powerful and flexible way to render thousands of 3D objects at once, and since it uses the VFX graph, it’s really easy to control where each object is and what it looks like.”

“These next two updates are the type where I imagine two possible reactions: you're thinking ‘Wow that’s a pretty boring update,’ or you are jumping out of your chair yelling ‘Yippee! Hooray! Finally!’ We’ve had developers here at Snap and our external developer network asking for curves in VFX since forever, and now it’s easier than ever to control the size, color, and emission of particles using curves! Additionally, before the Spawn Redesign, even something as simple as stopping and starting particle emission using scripting used to be a little annoying to set up, and now you can do it in a single line using the ‘emitting’ API property.”

For instance, this effect uses Curves to give the hearts a bit of pop as they spawn in, and the emission API property is used to spawn the particles using the “KissStartedEvent.”

And last, but not least,  “Align to Camera” is now a node, instead of a subgraph, which offers more stability and even the ability to rotate the particles as they face the camera.

The team has had a big focus on VFX this past year. Each of these updates builds on the last, widening the amount of things that are possible to do in Lens Studio.

We’re excited to see what people can do with all these new tools, and know that we’ve got lots more on the way!