2077-gps-mod/README.md

2077 Edge Weight Mod

Experimental Cyberpunk 2077 GPS route-weighting mod tooling.

Feasibility

Cyberpunk exposes a native gamegpsGPSSystem, but the current public RTTI dump does not expose script-callable methods for replacing or overriding the GPS planner. The useful surface is the traffic lane resource data:

• worldTrafficPersistentResource.data.lanes
• worldTrafficLanePersistent.length
• worldTrafficLanePersistent.maxSpeed
• worldTrafficLanePersistent.flags
• worldTrafficLanePersistent.playerGPSInfo
• worldTrafficLanePersistentFlags.Highway
• worldTrafficLanePersistentFlags.GPSOnly

That strongly suggests the in-game GPS path is computed natively over the traffic lane graph, using lane metadata as edge cost inputs. A full replacement planner would require native hooks or patching the game executable. A feasible REDmod-style mod is to patch lane resources so highways and major roads have better effective costs than side streets.

Current Implementation

This repo currently contains a WolvenKit-export patcher:

python3 tools/patch_traffic_lanes.py exported-json-dir patched-json-dir

The patcher recursively scans WolvenKit JSON exports for lanes arrays that look like worldTrafficLanePersistent data and applies configurable speed weighting:

• highways get boosted toward a preferred GPS speed in the game's lane scale
• regular roads keep a moderate speed floor
• pavement, crosswalk, and disabled traffic lanes are left alone
• optional non-highway speed caps can make highways more attractive

After patching, deserialize the JSON back into CR2W and pack the resulting resources into an archive.

The toolbox now has WolvenKit CLI installed:

toolbox run --container 2077 bash -lc '$HOME/.dotnet/tools/cp77tools --help'

See docs/tooling.md for the end-to-end archive build flow. See docs/traffic-system-debrief.md for the detailed feasibility and traffic graph notes.

Status

A test archive was built from the local Flatpak Steam Phantom Liberty install and installed to:

Cyberpunk 2077/archive/pc/mod/zz_edge_weight_gps.archive

Build outputs are ignored by git. The installed archive should be treated as experimental until route behavior is checked in game.