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A third display upscaler beside FSR1, and the first one written for the hardware this app actually runs on: FSR1's two compute passes are the expensive outlier on mobile, while SGSR is a single pass Qualcomm designed for Adreno. The filter is Qualcomm's, BSD-3-Clause, unchanged in substance. What differs is the shape around it -- theirs is a fragment shader over a fullscreen triangle, this is a compute pass, because that is what GSDevice already knows how to schedule. So the interpolated texcoord becomes a UV computed from the invocation id and the fragment output becomes an imageStore. The crop handling and the widened 0..2 sharpness range come from the Eden Emulator Project's port (GPL-3.0-or-later, compatible with PCSX2's GPL-3.0+); PCSX2 hands the pass a display rectangle inside a larger target, which is the same problem FsrEasuConOffset solves for FSR1. Deliberately a strict subset of what FSR1 already requires -- same descriptor types, same rgba8 storage image, textureGather with a constant component and no offset, which is core Vulkan 1.0 and needs no optional feature. So any driver already running FSR1 can run this, Turnip included, and there is no vendor gate on either. A driver that cannot compile the pipeline clears Features().sgsr and the renderer falls back to plain bilinear with an OSD notice, rather than failing. The Android upscaler control becomes a picker rather than an on/off toggle: three mutually exclusive upscalers expressed as two toggles that silently switch each other off is a worse way to say it than one list. FSR1 and SGSR share the existing sharpness slider -- the number means different things to each, but it is the same intent, and a second slider would only invite the two to disagree. ★ The Settings.kt clamp on the persisted enum was still bounded at UPSCALER_FSR1, and would have silently rewritten any SGSR selection back to Off. That clamp's own comment warns about exactly this failure; it still had to be updated by hand. Worth remembering the next time the enum grows. Suggested by CamilleLaVey, who authored the upstream changes (eden-emu #4293).