Building Big Games on Little Headsets

gamedeveloper.com:

Principle Graphics Engineer Ben Hopkins looks into the tools, tricks, and techniques used to bring Owlchemy Labs’ latest VR game Cosmonious High to the Quest 2.

When it comes to the tools we use at Owlchemy Labs, we live by the credo, “If it doesn’t exist, build it!”. Nowhere is this as important as performance and optimization. For the Quest 2 version of Cosmonious High, we built two new tools of note; the A/B Test Framework and the Multisample Anti Aliasing (MSAA) Cost visualizer.

Wanting to squeeze as much performance out of the Quest’s GPU as possible required finely tuned optimizations to shaders and rendering tech. RenderDoc is our most commonly used tool for GPU profiling and debugging on Quest; however, the timings it returns are relative to one another and not necessarily reflective of real-world cost.

Desiring more accurate GPU profiling, we wrote our benchmarking tool we call the A/B Test Framework. Using a collection of runtime components and editor code, we can quickly set up test suites (Scenes) containing any number of individual tests (GameObjects), which can then be automatically built, pushed, and run on the device in a single click. Once the test has finished running, results can be pulled from the device, saved to a special project asset, and displayed as a filterable graph.

While the AB Test component placed on each GameObject representing a test exposes a fair amount of additional conveniences, the underlying premise for testing is simple. At runtime:

When creating a test suite, the goal is for all tests to be deterministic and identical except for the element you want to profile and compare. A typical example would be comparing several different optimization options for a specific shader. In this case,