# Glossary

| Term | Definition |
| --- | --- |
| Blosm | Blender add-on (2.7.28) that imports OSM data as 3D building and street blockouts. Used for layout only — not authoritative for façade or height. |
| PIE | Play In Editor — an Unreal Editor feature that runs the current map as a live game session inside the editor window, with full game code, input, and physics, without packaging a build. Used for interactive verification (walk, reset, pause) before the scripted QA self-test. |
| Complex-as-simple collision | `CTF_UseComplexAsSimple`: Unreal collision mode where the render mesh triangles are used as the collision surface, instead of a simplified proxy. Required for terrain so the player walks on the actual ground shape. |
| DEM | Digital Elevation Model. 3DEP 1 m resolution GeoTIFF covering the demo bounds. Source of terrain heightfield. |
| El Capitan | El Capitan Entertainment Centre, 6838 Hollywood Blvd. The hero building of the demo. |
| Enhanced Input | Unreal’s modern input system (UE 5+). Uses Input Actions (`IA_*`) and Input Mapping Contexts (`IMC_*`) instead of legacy axis/action bindings. |
| EPSG:26911 | UTM zone 11N, the projected CRS used for the demo area. Local origin recorded in `Geo/`. |
| Hero façade | The detailed, reference-calibrated model of the El Capitan building frontage. |
| MPFB | MakeHuman Plugin for Blender (2.0.18). Generates parametric human base meshes with rigs and baked materials. |
| ODbL | Open Database Licence 1.0. The licence covering OSM-derived data. Requires attribution and may impose share-alike on derivative databases. |
| PlayerStart | Unreal actor that defines where the player pawn spawns. Positioned above grade so the capsule does not embed in the floor on spawn. |
| QA self-test | The `-qaselftest` command-line switch that runs an automated behaviour check (walk, reset, pause, ground transect) via a core ticker. |
| Site | The terrain, road, sidewalks, kerbs, and crossing markings — the ground-level infrastructure of the demo area. |
| Squash merge | Git merge strategy that compresses all branch commits into one commit on `main`, keeping a linear history. |
| Swept transect | A QA technique that raycasts vertically at regular intervals along a path (e.g. every 200 cm along both sidewalks and the carriageway) and counts holes (misses). Zero holes = the block is fully walkable. |
| UE | Unreal Engine — Epic Games' real-time 3D creation platform (version 5.8.4 in this project). Comprises the Unreal Editor (including PIE, content browser, viewport, blueprint editor), a C++ game framework, and runtime systems for rendering (Vulkan RHI on Linux), physics (Chaos), and input (Enhanced Input). The game project is `GigLine.uproject`; game code is a single C++ module in `Game/GigLine/Source/GigLine/`. |
| World Partition | Unreal's world composition system for large open-world levels. Not yet used in `0.1.0` but planned for `0.3.0+` driving routes. |
| Y convention | In Unreal, south = +Y, north = −Y (confirmed from street mesh orientation). In Blender, north = +Y; the `ue_metric_v1` export preset flips Y. |