gig-line/Docs/build.md

Build

Fresh-checkout build procedure. Completed 2026-11-07 after the pinned engine was installed and a blank Game/GigLine build was packaged and launch-tested.

Constraints

• Engine installation is external to the repository. Record its path and exact version in toolchain.md.
• Build output (Binaries/, Intermediate/, Saved/, DerivedDataCache/) is never committed.
• Large content is LFS-tracked, so a fresh clone needs git lfs install && git lfs pull before any build.

Engine

Pinned install: Unreal Engine 5.8.4 (CL 58902052, promoted build) at /run/media/system/DATA/Engines/UE_5.8.4. The engine bundles no Linux clang; the system clang (23.1.4, Fedora 45) is the game-code toolchain. Game targets must use BuildSettingsVersion.V7 to share the installed editor's build environment.

Fresh-checkout build

git clone <remote> gig-line && cd gig-line
git lfs install && git lfs pull
Tools/check-lfs.sh                 # must pass before any content build

# Compile the project's editor target (first build also proves the toolchain)
cd /run/media/system/DATA/Engines/UE_5.8.4
Engine/Build/BatchFiles/Linux/Build.sh GigLineEditor Linux Development \
  -project="$PWD/../../Documents/06-games/gig-line/Game/GigLine/GigLine.uproject" \
  -WaitMutex
# Expected tail: "Result: Succeeded"; module binary lands in
# Game/GigLine/Binaries/Linux/libUnrealEditor-GigLine.so

# Open in the editor (GUI, Vulkan)
./Engine/Binaries/Linux/UnrealEditor \
  /run/media/system/DATA/Documents/06-games/gig-line/Game/GigLine/GigLine.uproject

Adapt the -project= path to the actual checkout location.

Package a Linux build

cd /run/media/system/DATA/Engines/UE_5.8.4
Engine/Build/BatchFiles/RunUAT.sh BuildCookRun \
  -project="/run/media/system/DATA/Documents/06-games/gig-line/Game/GigLine/GigLine.uproject" \
  -noP4 -platform=Linux -clientconfig=Development \
  -cook -allmaps -build -stage -pak \
  -archive -archivedirectory="/run/media/system/DATA/Builds/GigLine" \
  -unattended
# Expected: "BUILD SUCCESSFUL" (~1 min for the blank project; archive ~1.1 GiB)
# Launch test (plain, no -map): /run/media/system/DATA/Builds/GigLine/Linux/GigLine.sh

Launch test must open the DemoMap. A plain ./GigLine.sh should load /Game/Hollywood/DemoMap (set via DefaultEngine.ini GameMapsSettings). If it instead opens /Engine/Maps/Templates/OpenWorld, the game shows an empty non-interactive "stuck" scene — check that GameDefaultMap is in DefaultEngine.ini, not DefaultGame.ini. Confirm the loaded map in the engine log: .../Linux/GigLine/Saved/Logs/GigLine.log (LoadMap: /Game/Hollywood/DemoMap). The archive directory is deliberately outside the repository; never archive into the checkout.

Headless content checks

Both content-acceptance tests run headless and are the template for all asset import verification:

# Static-mesh scale test (Blender export -> Unreal import -> measure)
#   Blender: Tools/scale_test_export.py, Unreal: Tools/ue_scale_test_import.py
# MPFB character (generate -> rig -> bake -> export -> skeletal import)
#   Blender: Tools/mpfb_character_export.py, Unreal: Tools/ue_character_import.py

# Unreal side of any test:
./Engine/Binaries/Linux/UnrealEditor-Cmd \
  /run/media/system/DATA/Documents/06-games/gig-line/Game/GigLine/GigLine.uproject \
  -run=pythonscript -script=<repo>/Tools/<script>.py -nullrhi -unattended -nopause -stdout
# Note: 5.8 swallows Python print() in the commandlet; scripts write result files to /tmp.

Content pipeline (current)

The hero block and the demo level are built by a fixed sequence. Each step writes a result file under /tmp/gigline/; read it, because the commandlet's own stdout can be swallowed.

Step	Tool	Output
OSM blockout	Art/blender/blockout/blosm_blockout.py	Art/blender/blockout/blockout-*.blend
Terrain	Art/blender/terrain/terrain_from_dem.py	Art/blender/terrain/terrain-*.blend
Street	Art/blender/street/street_mesh.py	Art/blender/street/street-*.blend
Site assembly	Art/blender/site/site_assembly.py	Art/blender/site/site-*.blend
Site export	Art/blender/site/export_site_fbx.py	six FBXs, one per mesh
Hero façade	Tools/hero_facade_build.py	Art/blender/hero/hero-facade-*.blend + JSON report
Site import	Tools/ue_import_site.py	/Game/Hollywood/Site/*
Hero import	Tools/ue_hero_facade_import.py	/Game/Hollywood/ElCapitan/SM_HeroFacade
Demo map	Tools/ue_build_demo_map.py	/Game/Hollywood/DemoMap
Review shots	Tools/ue_build_review_map.py + Tools/render_screenshots.sh	Screenshots/

Two rules that the pipeline enforces rather than documents:

• One conversion. Metres to Unreal centimetres happens only in Geo/tools/osm_common.py::to_unreal_local. Sidecars (<asset>.geo.json) record the result and Geo/tools/asset_metadata.py audit re-derives it.
• Collision is decided at import, not later: terrain, road and sidewalks are complex-as-simple; kerbs and props stay simple. A simple hull over a kerbed street ramps straight across the kerb.

Known engine quirks (2026-11-07)

• One handled PSOPrecache ensure fires at packaged-build exit only; not blocking.
• Interchange 5.8 does not create material/texture assets for skeletal FBX imports — Tools/ue_character_import.py finishes that chain explicitly.
• Android Turnkey status errors and datarouter DNS warnings in logs are benign.

Packaged Linux build

• 2026-11-07: blank Game/GigLine Development build packaged via the command above; 1.1 GiB archive at /run/media/system/DATA/Builds/GigLine/Linux; GigLine.sh launched on the desktop session, Vulkan swapchain created, 759 frames rendered across a 60 s smoke test. Controls document to be written with the first playable (0.1.0 Gameplay section).