seedds
f5646efc47
Outdoors in Breath of the Wild (the user's Great Plateau save, Mac M4 Pro) a frame had about 386 render passes and loaded and stored about 900 MB of attachments, which an iPhone at 60 fps can hardly move (about 55 GB/s). 220 of those passes ended only because the game updates the first 64 bytes of a 64 KB vertex uniform block before each draw group (nvnCommandBufferUpdateUniformBuffer inside the pass) while its shaders read up to 544 bytes of it. A deferred update that covers only part of what a draw reads used to end the pass. - Partly covered blocks (nvn_mtl.m ubp_get): the shadow starts from memory and takes every inline update queued in the submission, newest last, incrementally per range. It is refused, and the pass ends as before, when something else may have written the range by the time the pass runs: a copy, fill or feedback write queued in the submission, a storage buffer a shader may write or a texture->buffer copy over it (sbw, by 4 KB page), or a GPU write or counter report of an earlier submission still running (gw). A counter report of the same submission does not count: the host writes reports on the CPU after the whole submission completes (Fire Emblem Engage writes its reports into a uniform block's page). DM_NVN_UB_PARTIAL=0 turns it off; DM_NVN_UBP_CHECK=1 lands the updates, waits for the GPU and compares every shadow with memory. - cb_extent.tsv (new tool dm/gfx/tools/cb_extent.py, c1_guard.py's interval arithmetic over the translated MSL): per shader, how far into each uniform slot it can read, and the storage slots it never writes. Like c1_full.tsv, the host loads it only for its chain version; build_ipa.sh copies it, the NSP script writes it for provisional profiles, and the chain procedure regenerates it. Without it bindings are copied whole (up to 64 KB). Ten profiles have one. - Route B's reflection never says whether a storage buffer is written, so every one read as read-only and its writes went unnoticed: a storage buffer now counts as written unless SPIRV-Cross typed it const (nvn_refl.m sbuf_rw) or cb_extent.tsv proves the slot unwritten. - Lazy clears (lc_*): a set of targets that gets only clears before the game sets other targets no longer opens a pass just to store them; the next pass that attaches the same texture level and layer through the same view clears it as its load action, and the rest land as before before anything else could see them. Breath of the Wild's four clear-only passes before the G-buffer fold into its first pass. Off in TBDR mode; DM_NVN_LAZY_CLEAR=0 turns it off. - The residency set line counts shadows from memory, refusals by reason, and lazy clears. On the Mac, old (DM_NVN_UB_PARTIAL=0 DM_NVN_LAZY_CLEAR=0) and new side by side on each game's route; attachment loads + stores per frame: - Fire Emblem Engage battles: about 1,850 -> 360 MB, 88 -> 38 passes. - Tears of the Kingdom: about 1,100 -> 700 MB, 124 -> 116 passes. - Breath of the Wild outdoors: 386 -> about 158 passes, GPU p50 about 9.3 -> 6.5 ms, submit 5.7 -> 4.2-4.9 ms; where the old host fell to 30 or 20 fps under load, the new held 60. - Link's Awakening, 13 Sentinels: about 15% less. Super Mario 3D World: 5% less (lazy clears). - Odyssey, Three Houses: 2-8% less. Mario Wonder, Metroid Dread: unchanged. No new red lines in any of them. The shadow check found every shadow equal to the GPU's memory (BotW 346,000, Engage 284,000, TOTK 86,000), and t_nvn passes 68/68. Screenshots differ only by timing. Tried and dropped: DM_NVN_TBDR=1 (it turns the deferred updates off), DM_NVN_BARRIER=game (no gain), and same-target continuation outside TBDR mode (BotW's decals end the pass anyway). What still splits BotW's big passes: the GPU particles' compute dispatches (about 190 MB a frame) and decals that sample the G-buffer. Mac shader libraries were built for the current chain of TOTK, Engage, Wonder, Dread, Odyssey, Link's Awakening, Three Houses and 13 Sentinels (c1_full.tsv headers already matched). The IPA ZeldaBreathOfTheWild-2026-10-21-passes.ipa (an earlier state of these changes plus the uncommitted frame-step probes) awaits an iPhone test.
nxnative
Play your own Nintendo Switch games natively on iPhone and iPad. Bring your game (its NSP files) and your prod.keys; one script turns them into an IPA that you sideload.
It is not an emulator: the game's own code runs directly on the Apple chip, with Switch graphics rebuilt on Metal. Nothing from any game is in this repository, and the project is not affiliated with Nintendo or any game publisher.
Acknowledgements
This project is built on other people's work:
- d2r-mobile (MIT) developed this native-execution approach, for Diablo II: Resurrected. nxnative (first called smbw-mobile) started as a copy of its generic parts: the NSO rewriter, the host that stands in for Horizon, the NVN-on-Metal layer and the iOS app shell. Fixes go both ways.
- Ryujinx (MIT): its shader translator (
Ryujinx.Graphics.Shader,Ryujinx.CommonandSpv.Generator1.3.2, indm/third_party/ryujinxwith a few fixes listed in its README) turns the games' Maxwell shaders into SPIR-V. Its emulation of the kernel and system services is also a reference when the host's behaviour is in doubt. - Atmosphère: its kernel, mesosphère, is the reference for Horizon's synchronization semantics (address arbiter, condition variables).
- yuzu: Maxwell instruction encodings for the shader reference tool, and a cross-check for kernel behaviour.
- LibHac: reads NSPs and layers updates over the base game in
dm/tools/nx_extract. hactool did the first extractions. - SPIRV-Cross: SPIR-V to Metal Shading Language.
- deko3d (zlib): its texture layout size algorithm is ported in
dm/gfx/nvn/nvn_tex.c. - libvpx (VP9 movies), stb_vorbis (movie sound), the Vulkan headers and NVIDIA FLIP ship in
dm/third_partywith their licenses (list). - Capstone, lz4, fontTools and XcodeGen are used by the build.
Games
All of these are tested on an iPhone and playable:
| Game | IPA | Notes |
|---|---|---|
| Super Mario Bros. Wonder | ~4 GB | |
| Fire Emblem Engage | ~15 GB | Upgraded to 60 fps (30 fps on Switch); the upgrade needs update 2.0.0, it does not work with other versions |
| Metroid Dread | ~5 GB | |
| 13 Sentinels: Aegis Rim | ~5 GB | |
| Super Mario 3D World + Bowser's Fury | ~3 GB | |
| The Legend of Zelda: Breath of the Wild | ~16 GB | Upgraded to 60 fps (30 fps on Switch); the upgrade needs update 1.9.0, it does not work with other versions |
| The Legend of Zelda: Link's Awakening | ~6 GB | |
| Super Mario Odyssey | ~6 GB | |
| Hades | ~4 GB | |
| Hyrule Warriors: Age of Calamity | ~15 GB | Upgraded to 60 fps (30 fps on Switch); the upgrade needs update 1.3.0, it does not work with other versions |
| Fire Emblem: Three Houses | ~13 GB | Upgraded to 60 fps (30 fps on Switch); the upgrade needs update 1.2.0, it does not work with other versions |
| Super Mario Galaxy | ~3 GB | |
| The Legend of Zelda: Tears of the Kingdom | ~17 GB | Upgraded to 60 fps (30 fps on Switch); the upgrade needs update 1.4.3, it does not work with other versions |
| Monster Hunter Rise | ~22 GB | Upgraded to 60 fps (30 fps on Switch); the upgrade needs update 16.0.2, it does not work with other versions |
| Ace Attorney Investigations Collection | ~7 GB | |
| Hades II | ~4 GB | |
| Unicorn Overlord | ~4 GB | |
| Rhythm Heaven Groove | ~3 GB | |
| Octopath Traveler 0 | ~4 GB | Upgraded to 60 fps (30 fps on Switch); the upgrade needs update 1.0.5, it does not work with other versions |
| Pokémon Legends: Z-A | ~6 GB | |
| Cuphead | ~5 GB |
 Super Mario Bros. Wonder |
 Fire Emblem Engage |
 Metroid Dread |
 13 Sentinels: Aegis Rim |
 Super Mario 3D World + Bowser's Fury |
 The Legend of Zelda: Breath of the Wild |
 The Legend of Zelda: Link's Awakening |
 Super Mario Odyssey |
 Hades |
 Hyrule Warriors: Age of Calamity |
 Fire Emblem: Three Houses |
 Super Mario Galaxy |
 The Legend of Zelda: Tears of the Kingdom |
 Monster Hunter Rise |
 Ace Attorney Investigations Collection |
 Hades II |
 Unicorn Overlord |
 Rhythm Heaven Groove |
 Octopath Traveler 0 |
 Pokémon Legends: Z-A |
 Cuphead |
Needs iOS / iPadOS 26 or later on an iPhone 15 Pro or newer (A17 Pro chip or later) or an iPad with an M1 chip or later: the games' textures are BC-compressed, and older iPhones can't read that format. Other games aren't supported yet. For them the script writes a survey and still tries its best to pack an IPA, guessing the game's settings; such an IPA may not start.
Pack an IPA
1. Get nxnative and its tools (once, on a Mac with Xcode and Homebrew):
git clone https://github.com/seedds/nxnative.git && cd nxnative
brew install xcodegen zstd spirv-cross
brew install --cask dotnet-sdk
python3 -m pip install lz4 capstone fonttools
2. Put one game's NSPs in a folder, base game (an NSP, or an XCI cartridge dump) and update (and any DLC):
~/Games/MarioWonder/
Super Mario Bros. Wonder [010015100B514000][v0].nsp
Super Mario Bros. Wonder [010015100B514800][v327680].nsp
3. Run the script:
python3 scripts/build_ipa_from_nsp.py ~/Games/MarioWonder -k ~/keys/prod.keys
The IPA appears in the same folder (here ~/Games/MarioWonder/SMBWMobile.ipa). The first build takes 30–60 minutes, later ones about 10. You need free disk space of about twice the NSPs' size plus 10 GB. Options such as -o (output path) and --app-name are listed by -h.
4. Install the IPA with your sideloading tool (AltStore, Sideloadly, LiveContainer, …). The app gets the game's name, icon and version (the update's version, for example 1.2.1 for Mario Wonder; the base game's when there is no update).
Play
Touch controls. Tap 2D / 3D at the top to switch layouts; the app remembers your choice. Wonder, Engage, Dread, 13 Sentinels and Link's Awakening start in 2D, the other games in 3D. In 3D, the right stick (the camera in most games) is not drawn: swipe on the right third of the screen, starting anywhere off the buttons. In Super Mario Galaxy, other touches outside the controls move the pointer. A connected game controller hides the touch controls and keeps every button.
- Game language is English by default. For Chinese, add the line
DM_LANG=zh-HanstoDocuments/env.txt. - Saves and logs are in the Files app, under the app's name:
save/andlog.txt. When something goes wrong, sendlog.txt(the previous run islog.prev.txt). - Short stutters the first time a new scene appears are normal: the app compiles graphics for it once and remembers them for the next launch.
- Reinstalling: some sideloading tools give a reinstalled app a new data folder. Copy
save/andpso_user.tsvover from the old one to keep your progress. - Settings without rebuilding: put lines like
DM_OPMODE=0(handheld mode: lower resolution, higher frame rate) inDocuments/env.txt.DM_FPS_TARGET=30keeps Breath of the Wild, Tears of the Kingdom and Octopath Traveler 0 at their original 30 fps, which saves battery.DM_SHOW_FPS=1shows the frame rate at the top left (--show-fpswhen packing turns it on from the start).
Known issues
- No amiibo and no online features.
- Fire Emblem Engage: after switching away from the app and back, some sounds may stay silent until you restart it.
- Fire Emblem: Three Houses: small square patches on the ground where decals land.
- Super Mario Galaxy: effects drawn as points or lines come out one pixel wide.
For developers
How it works, the script's options, running games on the Mac, adding a game, and per-game notes: docs/development.md. In-depth bring-up and debugging notes: docs/agents.
License
MIT (see LICENSE). Third-party code keeps its own license; see dm/third_party.