Scale the valid presented image with MetalFX's spatial scaler on the shared Metal 4 path, preserving crop, letterboxing, origin and gamma-encoded colours. Keep Standard as the default and fall back when scaling is unsupported. Use the same path for asynchronous whole-window captures and diagnostic screenshots, retaining resources until GPU completion. Bound scaler recreation during resizing and report presentation GPU time separately by scaling mode. Put all launcher settings on one screen with Game, Controls and Performance sections, inline menus and sliders, and a reset to tested defaults. Extract the settings model for native persistence tests, validate saved ranges, share HUD setup, and document the measured costs without claiming an iPhone baseline. Validated with Metal presentation, NVN and snapshot regressions; tool and iOS tests; the Mac host; and an unsigned iOS smoke build. No new device gameplay run. Co-authored-by: v0lumehi <aljic.zijad@gmail.com>
Subsystem references
How the host meets each part of a Switch game, and every failure met so far, one entry per mechanism: symptom, cause, fix (file and function), the games it was found on (linked to their notes in dm/games/<id>/README.md). Start from the symptom index when you have a log line or a visible result; the workflows that lead here are in docs/agents.
| File | Covers |
|---|---|
| rewriter.md | The NSO rewriter patch_nso.py: jump tables, exclusive windows, patch area reach, cuts and observation gates, functions without unwind entries, stack and system registers, relocations |
| memory.md | Guest layout, heap and application pool, virtual address memory and the alias region (the SDK's node area), engine allocators, mapping SVCs, running out of memory |
| threads.md | Thread creation and cores, address arbitration, yields and spin waits, events |
| services.md | SDK calls and system services: sm connections, names that changed between SDKs, file system and saves, add-on content, input, keyboard and applets, display and operation mode, accounts and network, settings and fonts, C library and time, modules |
| movies.md | The SDK's movie library: decoder lifecycle, output slots, native-texture output, demuxers and codecs, game movie players |
| audio.md | The audio renderer and its command lists by SDK, AudioOut and devices, codecs, timing |
| frame-rate.md | The host's frame step, engine frame limiters, present intervals and display rates, CPU cost |
| nvn-objects.md | NVN object sizes, memory pools, command memory, queues and syncs, CPU-written textures, NVN entry points |
| rendering.md | The replay on Metal: textures, passes and clears, blend / depth / stencil, vertex input, uniforms and ordering, conditional rendering; the Vulkan and OpenGL layers |
| shaders.md | Shader containers by engine, control sections and code, translation, bindings and handles, shaders compiled at run time, pipelines and caches |
| game-state.md | Saves, scripted state, and game behaviour that looks like a host bug but is not |
A new general finding goes into the file and section it belongs to, in the same form, with a line in the symptom index; a fact about one game goes into that game's note.