Entire books could be written about lighting in Unity 5, but here is a brief mishmash of notes from the past few months of work in Unity 5. I’ve split it into 6 sections:

• Forward vs. Deferred Rendering
• Realtime vs. Baked Lighting
• Engine Lighting Tools
• Lighting Scenarios
• Performance Tips
• Post Processing

Most of this is applicable to any content made with Unity, not just virtual reality applications. This is a fairly high-level overview but it does assume some prior knowledge of basic graphics & lighting concepts. Let’s begin!

Forward vs. Deferred Rendering Paths

When in doubt, go with a forward rendering path. It’s ideal for VR applications for several reasons. Forward rendering has a low upfront performance cost, it’s easier on the CPU with fewer draw calls, it runs well on mobile VR devices, and it supports anti-aliasing as well as translucent materials. Here’s a quick overview to...

By now, this is obvious advice to any VR developer: you can positionally move a VR camera using a traditional gamepad thumbstick but any form of yaw rotation (mouselook or thumbstick rotation) causes extreme player discomfort.

Stick yaw control is such VR poison that removing it may be the right move – swivel chair/stand or don’t play.

— John Carmack (@ID_AA_Carmack) January 8, 2015

That being said, I found an edge case where rotation works smoothly, without any player discomfort.

The environment

The player is floating in space, with a large, rotating planet in front of them. There are thousands of objects on the surface of the planet (trees, buildings). As you would expect, when the planet rotates, the objects on the planet surface rotate along with it.

This poses an engineering problem. Each object on the planet surface incurs a draw call – this is very expensive for...

VR applications are far more computationally intensive than non-VR counterparts, making performance optimization a crucial task. If you’re targeting the mobile devices like the GearVR, this becomes even more paramount.

These are performance metrics you should try and hit:

• 50 draw calls per eye. Unity 5 more accurately refers to them as setpass calls.
• Fewer than 50K-100K vertices & 50K-100K polygons in your scene.

Here’s a bag of simple tricks you can use to hit those numbers:

Static batching

You probably have a ton of static geometry in your scene such as walls, chairs, lights, and meshes that never move. Mark them as static in the editor. Be sure to mark them as lightmap static in order to get baked lightmap textures. Instead of incurring a draw call for each individual object, objects marked as static can be batched into one combined mesh.

Static batching has one crucial...

I’ve spent the past 2 months developing a virtual reality application for PC (Oculus Rift) and mobile (Samsung GearVR). I used Unity 5 and the Oculus PC (0.5.0.1-beta) and Mobile (0.5.1) SDKs. Here are some lessons learned that will save you time.

Oculus PC and Mobile SDK can be used together

In Unity, you can use the two SDKs simultaneously. The Mobile SDK is under OVR>Moonlight (fun fact: Project Moonlight was the internal codename for the GearVR project). They share many resources, including the OVRCamera prefabs.

For example, if you use a OVRCameraRig in your scene, there is no additional work needed for it function properly on the PC or on mobile. It Just Works^TM

Setup separate Unity project folders

Unity stores platform-specific data, like compressed textures in /Library. Unity’s texture compression runs as a slow, single-threaded process. Large textures like lightmaps can...