An infinite canvas: Google announces Tilt Brush for Oculus Quest

“Tilt Brush is designed for creators — whether you’re a casual doodler or a professional artist,” says Google Product Manager Elisabeth Morant. “Over time, we’ve seen the product used in ways we never would have imagined — from bringing our favorite Disney characters to life, to prototyping what became a Time Magazine’s best of 2018 invention, to 3D printing and casting a Tilt Brush self portrait as a bronze statue. The possibilities are endless, and we’ve only just scratched the surface.”

We sat down with Morant to learn more about Tilt Brush and the work it took to bring this impressive creative tool to an all-in-one VR system.

What was the initial inspiration behind Tilt Brush? How has it changed over the course of development?

Elisabeth Morant: From the very beginning, we found that Tilt Brush resonated with two core audiences. On the one hand, we had our creators, who were excited by the possibilities of creating art never before possible with this unique new medium. And on the other hand, we found over and over people (consumers and developers alike) told us that Tilt Brush was their very first introduction to VR — or at least, room-scale VR. It’s been important to us for the lifetime of development that we continue to build features that raise the skill ceiling of what’s possible for creators, while also making sure the product is easy to pick up and use for first timers.

Why did you decide to bring Tilt Brush to Quest?

EM: When we learned that Oculus was building a cord-free standalone headset, we knew we had to bring Tilt Brush to Quest. This new form factor will unlock completely new opportunities for our artists to create. We’ve already seen dancers adopt Tilt Brush to visualize their movements in VR, but the opportunity for fully free movement and creation will lead to art that we never could have dreamed up before.

How did you go about bringing Tilt Brush over from PC VR to a mobile chipset?

EM: Most of our work porting Tilt Brush to Quest focused on performance improvements. Luckily, some decisions we made early on set us up for early performance wins. For example, instead of recreating stroke meshes on the GPU for every frame, Tilt Brush strokes are converted from their internal control point representation into geometry only once: either when the user first creates the stroke, or when the sketch is loaded from disk. The GPU then just has to render a list of pre-generated triangles. Another early easy win for us was to switch over our stroke rendering from double-sided to single-sided, using the shader to draw the reverse side of the stroke, and instantly halving our triangle count.

We also had to make a few visual changes as well. For example, the PC version of Tilt Brush uses a full-screen pass to render selected objects, perform a blur on them followed by a threshold to create an outline effect. Doing a full-screen effect that would involve a read-back was not feasible on mobile. We tried various options to do outlining on strokes, and in the end we chose to go for a solution that looked completely different:

Did you run into any technical obstacles?

EM: One of the biggest challenges we had was making the bloom effect available on mobile. Bloom is the lighting effect that makes our brushes glow in the trademark Tilt Brush style. It’s challenging to run bloom fast on mobile, but we knew it was key to that “wow” factor for the first-time Tilt Brush experience. That said, we also observed, looking at some of the most complex sketches made by our more prolific artists, that most of them veered away from using those brushes that utilized that effect. Our compromise was to enable bloom at the start when the user is just playing, and then gradually fade it out as their sketch becomes more complex. This way, we could give users that mind-blowing first-run experience, while also maintaining performance quality for artists sketching much more complex pieces.

We did end up removing some features that depend on the device being attached to a PC, such as Audio Reactive mode which depends on having access to system audio. Trade-offs were made during the course of development, but ultimately having a product that runs smoothly on mobile made it all well worth it.

Any advice you’d share with new creators and artists looking to build for VR?

EM: For those looking to try their hand at VR painting, just load up Tilt Brush and go! Our goal is for our experience to be as easy to pick up and play as it is to pick up a pencil and start sketching — the only limit is your imagination.

For those looking to get started with VR development, an easy way to get assets for your project is to use the Poly API — this will let you grab Tilt Brush sketches, Blocks models, and other assets from Poly and pull them directly into your Unity scenes.

If people take one thing away from Tilt Brush on Quest, what do you hope it would be and why?

EM: Tilt Brush: now untethered! On a more serious note, Tilt Brush on Quest should look and feel pretty much the same as the Rift version, with a few small tweaks. We hope this version of Tilt Brush feels even more magical than the Tilt Brush you already know and love.

Anything else you’d like to share with our readers?

EM: As you create art with Tilt Brush on Quest, upload it to Poly and share it on your social channels with the hashtag #TiltBrush. We’ll be featuring our favorite sketches on Twitter and in the in-app sketchbook.

Thanks for taking the time to chat with us, Elisabeth. We can’t wait for even more people to explore the world of VR art creation with Tilt Brush on Quest!