gig-line/Docs/Architecture/05_building_block_view.md

Building Block View

Whitebox Overall System

The system decomposes into five top-level building blocks:

Name	Responsibility
Gameplay	Player pawn, movement, camera, input bindings, HUD, game mode
Site	Terrain, road, sidewalks, kerbs, crossing markings, site-level collision
Façades	Hero façade (El Capitan), south block frontage, north-side buildings
Art Pipeline	Blender models, geographic data, export scripts, import scripts
QA & Review	Screenshot pipeline, self-test harness, visual review workflow

Gameplay

C++ classes in Game/GigLine/Source/GigLine/:

Class	Responsibility	Key detail
AGigLineCharacter	First-person player pawn	1.75 m capsule, 4.5 m/s walk, Enhanced Input bindings, reset, pause, -qaselftest harness
AGigLineGameModeBase	Sets game mode and HUD class	HUDClass = AGigLineHUD
AGigLineHUD	HUD text overlay	DrawText every frame: controls bottom-right, and an F3 debug readout top-left (gigline.Debug, on for -perf/-qaselftest)
AGigLineNPCPerson	NPC prefab (future)	Capsule + visible MPFB body, feet on Z 0
AGigLineShotActor	Screenshot camera walker	Drives cameras in -game mode, FScreenshotRequest, quits
UGigLineAssetTools	C++ collision helpers	SetComplexCollisionAsSimple on StaticMesh assets

Input assets in /Game/Input/: IA_Move, IA_MoveBack, IA_Strafe, IA_StrafeLeft, IA_Look, IA_Jump, IA_Reset, IA_Pause, IA_ToggleCamera, IA_ToggleDebug, bound in IMC_Default.

Player-facing bindings: WASD move, mouse look, Space jump, R reset, Escape pause, V swap first/third person. The camera and body work landed with 0.2.0 (see ADR-9): the shipped default view stays first person, and -thirdperson starts the pawn in the third-person rig — used by the screenshot run so the review is reproducible.

Site

Static meshes and materials in /Game/Hollywood/Site/:

Asset	Role
Terrain_DEM	Ground heightfield (complex-as-simple collision)
Road_Hollywood	Carriageway surface (block-all collision)
Sidewalk_North, Sidewalk_South	Pedestrian surfaces (block-all collision)
Kerb_North, Kerb_South	Kerb edges
Crossing_Markings	Zebra markings at signalised crossing
M_Asphalt, M_Concrete, M_KerbConcrete, M_Ground, M_RoadPaint, M_Stucco, M_FacadeStone	Procedural materials (world-space-noise blend + roughness)

Façades

Asset	Role
SM_HeroFacade	El Capitan Entertainment Centre detailed façade
SM_ElCapitanTheatre, SM_Budget_6822, SM_Hollywood_6806, SM_Hollywood_6902, SM_Hollywood_6922, SM_LeeDrug_6800	South block frontage (6 buildings)
SM_Madame_Tussauds, SM_TCL_Chinese_Theatre	North-side buildings (within 50 m)
SM_Retail_LeeDrug, SM_Retail_6806	Retail trim over 6800 and 6806–6820, modelled from their own photograph (Tools/retail_frontage_build.py, staged as RetailTrim_*). 6822 Budget stays a bare volume: no photograph exists.

Art Pipeline

Python scripts in Tools/ drive the content pipeline:

Script group	Purpose
export_*, hero_facade_build	Blender headless export (FBX)
ue_import_*, ue_hero_facade_import	Unreal headless import + placement
character_anim_build, ue_character_anim_import	Character animation clips (GigLine_Idle, GigLine_Walk) and their import
export_*, hero_facade_build, retail_frontage_build, theatre_trim_build, facade_kit_build	Blender headless export (FBX); trim builders work in world coordinates
ue_import_*, ue_hero_facade_import, ue_import_retail_detail	Unreal headless import + placement
ue_build_demo_map, ue_build_review_map	Map assembly (lighting, meshes, player start)
ue_create_input_assets	Enhanced Input actions + mapping context
render_screenshots.sh	Screenshot capture pipeline
judge_screenshot.py	Vision-model pre-check (optional)
input_emulation.py, input_test.py	OS-level virtual keyboard/mouse injection for input verification
Tools/_common.py	Pure helper shared by Blender builders, importable without Blender (bay layout)
Tools/tests/	Stdlib unittest tests for the pure parts of the tools (requirements-tools.txt)
Geo/tools/mapbox_buildings.py	Second height source: Mapbox mapbox-streets-v8 building data vs our OSM heights

Source data: Art/blender/ (.blend files), Geo/ (OSM extracts, DEM, verification docs). Tool rules (one script one job, result files for commandlets, clean worktree for generators, documented inventory, tests for the pure parts) are in AGENTS.md.

QA & Review

• AGigLineShotActor walks fixed cameras in -game mode, captures PNGs, and quits.

• -qaselftest switch on AGigLineCharacter runs a core-ticker harness: walk 2 s, reset, pause/unpause, ground transect — all PASS/FAIL logged.

• Screenshots/ holds committed PNGs and README.md approval table.

Level 2

White Box Gameplay — Input Flow

1. AGigLineCharacter::SetupPlayerInputComponent binds IA_* actions to MoveForward, MoveBack, MoveStrafe, MoveLeft, Look, StartJump/StopJump, ResetToStart, TogglePause.

2. Movement delegates to ApplyMove(Forward, Strafe) → AddMovementInput.

3. Look applies yaw/pitch scaled by LookSensitivity (Y invertable via bInvertLookY).

4. ResetToStart teleports to StartLocation (captured on first grounded frame), clears velocity, resets control rotation.

5. TogglePause toggles APlayerController::SetPause, swaps input mode between FInputModeGameOnly and FInputModeUIOnly, shows/hides mouse cursor.

White Box Site — Collision Model

• Every site mesh (road, sidewalks, kerbs, crossing) is STATIC with BlockAll collision.

• Terrain_DEM uses CTF_UseComplexAsSimple (forced by UGigLineAssetTools at build time, saved on the asset).

• The terrain corridor is carved to half-width 10.7 m around the road centreline so the player can walk the carriageway and both sidewalks.

• Ground Z: north sidewalk 395, road 366, south sidewalk 317 (3.94 m fall along the block, matching the DEM).