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Image reference (original game): The Elder Scrolls V: Skyrim - Special Edition · original-game artwork, provided by IGDB. Image rights remain with their respective owners. This illustrates the referenced original game, not the actual visuals of this rewrite or mod.

Source maintainer: ShinyStarSam · Revision: df26f6597ae2 · Catalogued: 2026-10-12

Source license: MIT · LICENSE · Article: Source README (format adapted)

The source README follows, with formatting adapted for this site and images replaced by source links. Feature, completion and testing claims belong to its authors and have not been independently playtested here. The Traditional Chinese translation was prepared with AI assistance.

Gmod x Skyrim

Play Skyrim as a Garry’s Mod player: Garry’s Mod movement, weapons, health and HUD inside the real
Skyrim world. Both games run at the same time and talk through shared memory, the same approach as
SkyCraft. See docs/DESIGN.md.

Status: early. Phase 0 done: Skyrim’s player follows Garry’s Mod. Phase 1 in progress: playing from the Skyrim window works.
Single-player and offline only. Garry’s Mod is always started with -insecure (VAC off).

What works

Garry’s Mod → shared memory (tested in game 2026-10-04): after lua_run require("gmsky")
in the console, Garry’s Mod’s player position, aim, speed and on-ground/crouch/alive state reach
shared memory 66 times a second, and a test program (fake_skyrim) reads them. Closing Garry’s
Mod is detected within half a second.
Skyrim plugin, read-only (tested in game 2026-10-04): loads through SKSE on 1.7.104, hooks the
player’s per-frame update, and reads Garry’s Mod’s live state through shared memory. It logs
both players side by side to logs/skyrim.log. It doesn’t change anything in Skyrim yet.
Skyrim’s player follows Garry’s Mod (tested in game 2026-10-04, Phase 0 done): walking and
looking around in Garry’s Mod moves and turns the player in Skyrim, about 60 updates a second,
standing on Skyrim’s own ground and hills. Closing Garry’s Mod gives Skyrim back its normal
controls within 2 seconds. You control it from the Garry’s Mod window, and Skyrim needs
bAlwaysActive=1 in its Skyrim.ini so it keeps running in the background.
Playing from the Skyrim window (tested in game 2026-10-04, Phase 1 step 1): W/A/S/D, Shift
(sprint) and the mouse move and turn the player with Garry’s Mod’s movement; E opens doors,
containers and talks to people in Skyrim; Esc, ~, J, M, F9, T, Tab, I, P and F5 (test 68) open
Skyrim’s menus, and input goes
back to Skyrim while a menu is open or the Skyrim window isn’t in front. Garry’s Mod runs at
full speed in the background (start it with tools/launch_gmod.ps1). The view doesn’t snap
after menus. Mouse look: Skyrim shows the mouse movement before Garry’s Mod has applied it,
and turns its camera directly (Skyrim’s own first-person camera trailed by up to 45 degrees
during fast turns); the user reports only a very small delay left. Settings in Garry’s Mod’s
console: gmsky_sensitivity (default 3), gmsky_predict, gmsky_camera (1 = on).
Smooth walking (tested in game 2026-10-04, Phase 1 step 2): Skyrim blends between Garry’s
Mod’s 66 updates a second instead of taking the newest one each frame; at steady speed the
per-frame steps vary by 1–6% instead of 27–44%. Adds ~15 ms to the position only (not the view).
gmsky_smooth 0 turns it off.
gmsky loads by itself (tested in game 2026-10-04): one small file,
garrysmod/lua/autorun/server/gmsky_autoload.lua, installed once with
tools/install_gmod_autoload.ps1, loads gmsky in single-player once you’re in the map.
Garry’s Mod walks on Skyrim’s ground (tested in game 2026-10-04, tests 20–21): Skyrim
measures the ground around the player with rays, and Garry’s Mod’s own movement walks, jumps
and slides on it. The ground is triangles answered from Lua (no Garry’s Mod physics objects,
which crashed Garry’s Mod in tests 12–17). Test 21: 164 ground updates, no crash, no stalls;
Skyrim measures ahead of a fast player, so noclip launches never outran the ground.
Jumping and noclip (tested in game 2026-10-04, tests 17 and 21): Skyrim’s player follows
Garry’s Mod’s height; V toggles Garry’s Mod’s noclip from the Skyrim window; you fly
through Skyrim’s hills, and Skyrim’s own physics doesn’t push you back (contacts and Skyrim’s
“land rescue” are switched off for our player, as SkyCraft does).
Travel anywhere: no map edge (tested in game 2026-10-04, test 22): when you get far from
the middle of Garry’s Mod’s map, Garry’s Mod moves you and its link to Skyrim’s world back
together, so Skyrim’s position doesn’t change. Test 22: 42 re-centres (37 while walking with
gmsky_recentre_at 500, 5 in long noclip flights), 58,000 Garry’s Mod units ≈ 109,000 Skyrim
units from the start in one direction; position relative to the link identical before and
after every time; speed kept; no holds; the user: “works flawlessly”.
Skyrim’s real collision (tested in game 2026-10-04, test 23): Garry’s Mod’s movement
collides with Skyrim’s exact collision shapes: buildings, walls, stairs, arches, interiors,
trees, fences, rocks. Streamed from Skyrim around you as you move (adapted from SkyCraft);
gmsky_ground grid switches back to the older ray-grid ground.
Camera from Garry’s Mod’s eye (tested in game 2026-10-04, test 24): crouching lowers the
view smoothly, hard landings kick it (view punch), Skyrim uses Garry’s Mod’s FOV.
Crouch = Skyrim’s sneak (test 24): the stealth eye, NPC detection and sneak attacks follow
Garry’s Mod’s crouch.
tools/launch_gmod.ps1 loads gm_flatmap directly (test 24), with gm_flatmap.bsp in
garrysmod/maps.
Garry’s Mod’s hands, weapon and HUD inside Skyrim’s window (Phase 2, tested in game
2026-10-05, tests 42-50; on by itself since test 68): on at every start (gmsky_overlay 0 in Garry’s Mod’s console turns it off).
- Garry’s Mod’s hands, weapon, HUD (the patched HOLOHUD 2, see tools/build_holohud.py), menus
  and console are drawn over Skyrim’s world every frame, 7-9 ms old, with correct transparency
  (blended in linear light; checked by snapshot, gmsky_overlay_shot).
- Hidden while a Skyrim menu is open. The physgun’s grab outline (halo) works (test 45).
- HOLOHUD’s plates are frosted: Skyrim is blurred behind them (gmsky_overlay_blur 0/1).
- Skyrim’s own first-person arms and weapon, crosshair, health / magicka / stamina bars,
  compass, charge meters and arrow count are hidden while the overlay is on; they come back
  when it’s off.
- Garry’s Mod’s window moves off-screen while the overlay is on and comes back afterwards
  (gmsky_overlay_hidewindow 0 keeps it in place). Alt+Tab to it still works for its console.
Weapons and the spawn menu from Skyrim’s window (Phase 3 step 3a, tested in game
2026-10-05, tests 53-54): the mouse wheel and 1-6 open Garry’s Mod’s own weapon menu (HOLOHUD’s)
and a click picks; Q holds Sandbox’s spawn menu open, with a cursor moved by the mouse (drawn in
the overlay) and no camera movement while it’s out (gmsky_cursor_speed). The physics gun’s
wheel pushes / pulls a held prop. Not done: typing in the spawn menu’s search box, the C menu.
Shooting Skyrim’s NPCs (Phase 3, tested in game 2026-10-05, tests 56-60): every Garry’s Mod
weapon that fires bullets, the crowbar and the RPG hit Skyrim’s NPCs through invisible stand-ins
shaped like Skyrim’s own per-bone hitboxes (the copy matches Skyrim’s on 99.3-100% of test
rays, gmsky_hitbox_test), and the hits go through Skyrim’s own hit system: NPCs bleed, react,
fight back and die. Damage × 3, head shots × 2 more (gmsky_damage_scale,
gmsky_headshot_scale). You bump into NPCs like Garry’s Mod’s own; they shove you aside.
Skyrim’s NPCs hurt you (Phase 3, tested in game 2026-10-05, test 61): their hits take
Garry’s Mod’s health (HOLOHUD’s bar), 1:1 (gmsky_hurt_scale); Skyrim’s own health stays full and
Skyrim can’t kill you. Falling hurts once (Garry’s Mod’s own fall damage).
Dying and respawning (Phase 3, tested in game 2026-10-05, test 62): you die in Garry’s Mod
and click to respawn, all from Skyrim’s window; you come back at full health at the last spot
where nobody was fighting you. No Skyrim save reload.
Shooting corpses (Phase 3, test 64): Skyrim’s ragdolls are pushed with Garry’s Mod’s own
damage force × 3 (gmsky_ragdoll_force), at the spot hit; explosions throw the limbs apart;
killing shots and blasts throw the body as it falls.
Swimming (Phase 4, tests 67-68; W + Space swims forward and up together): Skyrim’s rivers and lakes are water in Garry’s Mod too: from
waist deep you swim with Source’s own water movement (swim where you look, Space up, sink
slowly, climb out at a bank); Skyrim shows you underwater, and drowning hurts you.
F1 opens Garry’s Mod’s console (test 64) in Garry’s Mod’s own window over Skyrim’s; close it
with ~ or Esc (or click back into Skyrim).
Garry’s Mod’s objects inside Skyrim’s world (geometry route, tests 75-80): props, rockets,
grenades, broken pieces, Garry’s Mod NPCs with their animations and weapons are drawn by Skyrim
itself in its own frame, with their textures; they stay put in the world and hide behind walls.
Lit by Skyrim’s own sun, ambient and lights at Skyrim’s brightness, with normal maps, Source’s
phong shine and glowing (self-lit) parts; outdoors they get Skyrim’s sun shadows and cast their
own onto Skyrim (tests 81-89). Indoors, Skyrim’s shadow-casting torches and fires shadow them too,
using Skyrim’s own shadow maps, and they cast shadows from those lights onto Skyrim and onto each
other (tests 94-95).
The player is as wide as Skyrim’s player (S2j, tests 137-140): Garry’s Mod’s box is sized
from Skyrim’s player collision (half width 10.9 instead of 16), so it fits through the same
places; the camera no longer cuts into walls up close, and far shadows are steady
(gmsky_size_from_skyrim 0 goes back to Garry’s Mod’s own size). After a load, the player is
pushed sideways out of walls (test 136).
Skyrim’s loose objects are solid (S2k-K1, test 142): plates, food, baskets, dropped weapons
and hanging objects near the player (up to 2,000 within 1,500 Skyrim units) get invisible copies
with their real shapes in Garry’s Mod’s physics. You bump into them and can stand on them.
Walking into one pushes it, but that push is Skyrim’s own: Skyrim’s player body shoves the real
object and the copy follows. Bullets, explosions and props don’t move them yet (step K2).

What doesn’t work yet

Doors: a door can leave an invisible wall where it was (test 136). Planned after S2k.
Skyrim’s loose objects can’t be moved by Garry’s Mod yet: bullets, explosions, props, the
physgun and the gravity gun don’t move them (S2k step K2, next).
Garry’s Mod’s effects are invisible in Skyrim (tracers, explosions, the physgun beam, sprites); planned as step G7.
A prop dragged with the physgun lags a little behind the view; phong values not fine-tuned (polish list).
Grenades and AR2 balls fall through Skyrim’s world and don’t hurt NPCs; the physgun can’t grab
NPCs or corpses (Garry’s Mod’s physics doesn’t see Skyrim’s world or NPCs).
Skyrim potions and healing don’t heal Garry’s Mod’s player. Skyrim’s ragdolls are still
Skyrim’s (stiffer than Garry’s Mod’s); Garry’s Mod’s own ragdolls need its physics to see
Skyrim’s world first.
Quest markers and locations: Skyrim’s compass is hidden while the overlay is on, and HOLOHUD’s
compass and minimap don’t show Skyrim’s markers yet (planned). No stamina / magicka display.
Garry’s Mod’s window size isn’t matched to Skyrim’s automatically: use
tools\launch_gmod.ps1 -Width W -Height H with Skyrim’s size (both are 1280×720 so far).
Ending noclip more than ~2,100 Garry’s Mod units under Skyrim’s ground holds you in place;
press V again.
The ground is now Garry’s Mod physics (gmsky_ground physics, the default since test 124):
props land on it (tests 118-123). gmsky_ground shapes switches back to the older traced
ground (props fall through it).
Stairs: invisible ramps are laid over Skyrim’s staircases (found by Skyrim’s stair materials),
so the player walks up and down smoothly: the big stone stairs, curved flights, stacked-box
steps and steps just too steep to walk (tests 133-134). The ramps are for the player only:
bullets, props and grenades meet the real steps (test 135).
Everything else in docs/DESIGN.md §12.

Credits

Built on the approach and parts of the Skyrim plugin of SkyCraft
by chasmlol (MIT). Details and license text: THIRD-PARTY-NOTICES.md.

Requirements

Skyrim Anniversary Edition 1.7.104, SKSE64 for 1.7.104, Address Library for SKSE Plugins
Garry’s Mod, 64-bit (gmod_win64.exe)
To build: Rust stable (MSVC), Visual Studio 2022 C++ tools, CMake

Folders

Folder
`protocol/`	Shared-memory layout used by both sides
`skse/`	Skyrim SKSE plugin (C++)
`gmod/`	Garry’s Mod module, loader stubs, Lua scripts
`tools/`	Test helpers and launch scripts
`docs/`	Design
`logs/`	Runtime logs (not tracked)
`build/`	Build output (not tracked)
`reference/`	Read-only SkyCraft clone (not tracked)

License

MIT. See LICENSE. Third-party code keeps its own license: see
THIRD-PARTY-NOTICES.md.

License and provenance

The README and its translation retain MIT terms. Changes comprise translation, links and formatting. Editable Markdown, the original README, LICENSE and NOTICE files are included in the linked bundle. This grants no rights to the original games, their assets or trademarks.

LICENSE

MIT License

Copyright (c) 2026 ShinyStarSam

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

THIRD-PARTY-NOTICES.md

# Third-party notices

## SkyCraft

Gmod x Skyrim copies SkyCraft's architecture (two games running at once, linked through shared
memory) and adapts parts of its Skyrim plugin. Thank you to chasmlol.

- Source: https://github.com/chasmlol/SkyCraft
- License: MIT (full text below)
- Adapted in this project (each file says what it took):
  - `skse/src/Input.cpp`: input bridge hooks (PlayerControls / MenuControls, E activates).
  - `skse/src/Camera.cpp`: turning Skyrim's camera directly after its camera update.
  - `skse/src/Smooth.cpp`: blending between the other game's ticks.
  - `skse/src/Puppet.cpp`, `skse/src/Probe.cpp`: the player puppet and its character
    controller handling (no momentum or fall damage, on-ground / in-air state, gravity kept on).
  - `skse/src/Terrain.cpp`: ground rays around the player ("stage A").
  - `skse/src/Body.cpp`: dropping the puppet body's contacts above its feet, skipping Skyrim's
    land rescue (from SkyCraft's `DigPhysics.cpp`).
  - `skse/src/Collision.cpp`: streaming Skyrim's Havok collision around the player region by
    region (layer list, shape decoding and the offsets SkyCraft found, guarded reads, triangles
    from boxes / capsules / convex hulls, refresh near the player, per-frame limits); and each
    triangle's Skyrim material at its key (SkyCraft's `Dig.cpp` `ShapeMaterial` /
    `GuardedMaterial` and `Collision.cpp` `FlagsFor`), used here to mark stair triangles (S2i-1).
  - `skse/src/Link.cpp` `RingWrite`, `protocol/src/shm.rs` `ring_write` / `ring_read`,
    `protocol/gmsky_protocol.h` "Collision ring": the byte ring with pad messages.
  - `gmod/module/src/shapes.rs`, `gmod/lua/gmsky/field.lua`: the idea of feeding Skyrim's exact
    triangles to the other game's collision query (SkyCraft's `TriCollider.java`); the swept test
    itself is our own.
  - `docs/DESIGN.md`: architecture.

```
MIT License

Copyright (c) 2026 chasmlol

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
```

## CommonLibSSE-NG

`skse/extern/CommonLibSSE-NG` (git submodule, not copied in): GPL-3.0-or-later with a modding
exception. See its own `LICENSE` and `docs/DESIGN.md` §14 question 4.

## Community Shaders (shader reconstructions)

Gmod x Skyrim reads Skyrim's indoor (parabolic) and sun shadow maps the way Skyrim's own shaders do,
as reconstructed by Community Shaders. Thank you to its authors.

- Source: https://github.com/doodlum/skyrim-community-shaders (read at commit `dd2677fc`),
  `package/Shaders/Utility.hlsl` (`RENDER_SHADOWMAP_PB` and `RENDER_SHADOWMASKDPB`)
- License of the shader files used: MIT (`package/Shaders/LICENSE`, full text below). The rest of
  that repository is under other terms; nothing else from it is used.
- Adapted in this project: `skse/src/World.cpp`: `ParabolicLookup` / `ParaboloidLight` (the
  dual-paraboloid lookup: light-local position, hemisphere choice, uv, depth = length / radius, and
  its soft 8-sample filter), `IndoorShadowVS` (drawing a dual-paraboloid map), the 8 spiral
  sample offsets from `package/Shaders/Common/Random.hlsli` (Jimenez's, as Community Shaders lists them),
  and for the sun `SkyrimCascade` / `SkyrimSunShadow` / `SunShadow` (`SampleShadowPCF`, the same
  filter on the sun's cascades, and the blend from cascade 0 to 1 in `RENDER_SHADOWMASK`).

```
MIT License

Copyright (c) 2022 Ilya Perapechka

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
```