factorio-gopher

A Factorio 2.0 mod that replaces the player character with the Go gopher.

Support

Available Option	API ID	No Armour	Base Armour	Mech Armour
Idle	idle	✅	✅	✅
Idle with gun	idle_with_gun	✅	✅	✅
Running	running	✅	✅	✅
Running with gun	running_with_gun	✅	✅	✅
Running with gun (flipped shadow)	flipped_shadow_running_with_gun	✅	✅	✅
Mining	mining_with_tool	✅	✅	✅
Airborne idle	idle_in_air	➖	➖	⚠️1
Airborne idle with gun	idle_with_gun_in_air	➖	➖	✅
Flying	flying	➖	➖	⚠️
Flying with gun	flying_with_gun	➖	➖	⚠️
Taking off	take_off	➖	➖	✅
Landing	landing	➖	➖	✅
Corpse graphics	pictures	✅	✅	✅
Corpse graphics (armoured)	armor_picture_mapping	➖	✅	✅

Roadmap

• Player-colour accents for multiplayer differentiation
• Animated ground idle and armed-idle cycles

There is no set timeline. Contributions are welcome.

Install

make install

This symlinks mod/ into Factorio's per-OS mods folder:

• macOS: ~/Library/Application Support/factorio/mods
• Linux: ~/.factorio/mods
• Windows: %APPDATA%\Factorio\mods

Then launch Factorio, open Mods, enable "Go Gopher", and load or start a game.

make uninstall removes the symlink. Override the location with go run ./cmd/gopher -mods <path> install.

Development

Tooling

Install via your package manager of choice. For example, on macOS with Homebrew:

brew install go jq golangci-lint busted luarocks luacheck markdownlint-cli2
luarocks install --local luacov

Sprite pipeline

Per-direction build-input PNGs live in mod/graphics/gopher-{n,ne,e,se,s,sw,w,nw}.png and mod/graphics/knight-{n,ne,e,se,s,sw,w,nw}.png at 1024 px by 1024 px. Edit those inputs, then regenerate the derived sheets:

make build

Derived runtime frames are 256 px by 256 px and render at scale = 0.15. Keeping the tracked inputs larger preserves generator quality without making Factorio decode the high-resolution working canvases at runtime.

This runs go run ./cmd/gopher all and writes gopher-running.png, gopher-shadow-*.png, gopher-8dir.png, gopher-running-with-gun-*.png, gopher-idle-with-gun*.png, knight-idle*.png, knight-running.png, knight-running-shadow.png, knight-running-with-gun*.png, knight-flying-with-gun*.png, knight-take-off*.png, and knight-hover*.png, plus the gopher-corpse*.png and knight-corpse*.png death sheets and both *-mining*.png cycles. Sprite changes do not hot-reload; exit to Factorio's main menu and reopen the save to pick them up.

The Go pipeline lives in cmd/gopher/main.go (entry point) and internal/*.go (run cycle, shadow projection, sheet stitching, PNG helpers). The Factorio prototype mutation is in mod/data-updates.lua.

Make targets

make help    # list every target
make build   # regenerate sprite sheets
make package # create build/gopher_<version>.zip for Factorio
make test    # Go and Lua tests; race detection + 100% coverage gates
make lint    # markdown + lua + go

Releases

Pushing a numeric version tag runs the Publish Factorio Mod workflow. The tag must match mod/info.json and point to a commit on master. The workflow rebuilds and verifies the sprites, runs the full validation suite, packages the mod, then uses go run ./cmd/publish to upload it through the configured Automation environment.

Factorio release versions cannot be uploaded twice. Always bump mod/info.json before creating the next tag.

Licences

Code: MIT (see LICENSE).

Gopher artwork: the Go gopher was designed by Renee French. Vector artwork by Takuya Ueda, from golang-samples/gopher-vector, licensed under CC BY 3.0. The vector source was rasterised to PNG and padded to a square canvas for use in this mod.

Knight gopher sprites are based on artwork by Egon Elbre, from egonelbre/gophers, released under CC0 1.0 (public domain). They appear only with mech armour from the Space Age expansion.

Footnotes

1. Not defined by vanilla Space Age; supported if present. ↩