Engineering notes from a Switch 2 emulator fork for integrated GPUs: what we measured, how we measured it, and what is still in progress.
Every number names the machine it came from: Core Ultra 9 285H with an Arc 140T iGPU, Intel driver 32.0.101.9175. Game fps counts only frames the game renders.
Translated shaders were searching the bound buffers for memory accesses they could not resolve ahead of time. Routing those accesses better cut a foliage draw from 15.7 to 5.8 ms on an Arc 140T, with the limits of one laptop and one scene.
Shaders · MeasuredFrame generation was on and motion still stuttered. The diagnosis (forced FIFO, a present thread not locked to vblank, fixed-fraction prediction) and the vblank-locked presenter that shipped in v20.1.
Frame pacing · Shipped in v20.1Timing marks on every boot phase show about 11 s of a 24.7 s boot going to Vulkan instance creation. What the marks log, what is being cut, and how to measure your own boot.
Boot time · In progressRules for coding agents, issues scoped so an agent can finish them, a loopback MCP server that reads and drives a running game, and a free CI build for every pull request.
Contributing · AI agentsEvery device except the Arc 140T is untested by the maintainers. Send a device report, run the benchmark, or pick an agent-ready issue. How to contribute.