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Open-World Player Vehicle Driving Series: The Player Takes Over a Car That Was Already Running on Its Own

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This is the prologue to the player-vehicle-driving subseries within “How to Build an Open-World Game.” It follows the earlier population, vehicle, and traffic-runtime articles. The vehicle series examined ownership, seat relationships, driving authority, and the execution stack inside one vehicle. The traffic series examined how multiple vehicles share road, junction, and event systems. This series … Read more

Dynamic City | City Traffic Runtime (Part 2): Route Execution, Driving Policy, and Multi-Vehicle Executors

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This article is the lower half of the traffic-runtime topic in the “How to Build an Open-World Game” series. It follows the upper half, which covers scheduling and decision-making: road networks, junction right of way, signal phases, dispatch orchestration, and traffic readiness. This article covers route execution, continuous replanning, driving policy, dispatch-task realization, and dedicated … Read more

Dynamic City | City Traffic Runtime (Part 1): Road Networks, Junction Right of Way, Traffic Signals, and Dispatch Orchestration

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Previous article: Vehicle Driving Execution Runtime and Physics Seams (Part 2) This article is the traffic-runtime installment in the “How to Build an Open-World Game” series, following the vehicle-runtime articles. The vehicle articles examine state organization inside one vehicle: driving ownership, seat relationships, driving-authority consistency, and the execution stack. This article moves to the higher … Read more

Dynamic City | Vehicle Driving Runtime (Part 2): Driving Execution Stack, Kinematic Preview, and Physical Integration

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This is the lower half of the vehicle topic in the “How to Build an Open-World Game” series. The previous article covered scheduling and decisions: the vehicle owns the persistent driving loop, the ped submits intent, seat relationships have an authority owner, driving authority supports arbitration and consistency checks, and LOD has explicit tiers. This … Read more

Dynamic City | Vehicle Driving Runtime (Part 1): Persistent Driving Intelligence, Seat Relationships, and Driving Authority

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This is one of the practical installments in the “How to Build an Open-World Game” series, following the two-part character article *Rebuilding a City Packed with People in UE5*. That article examined the runtime organization of a large population—world ownership, phase scheduling, population, and the perception pipeline. This article turns to the other half deliberately … Read more

Dynamic City | City Population Runtime (Part 2): Task Execution, Scenario Behavior, and Presentation Boundaries

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This is the second pedestrian-focused installment in the How to Build an Open-World Game series. Part 1 covered scheduling and decision-making up to the point where an event has produced a task slot. This article covers the other half: how a task becomes observable behavior, how scenario points populate the environment, and where locomotion, animation, … Read more

AI-Native Development in Practice — TPS Camera Overhaul (Part 1): Aligning Camera Placement and Framing by the Numbers

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Part of the “AI-Native Game Development” series. The June kickoff post named “converting FPS into TPS” as the first thesis to validate in Phase Two, and promised to “record completion as completion, and setbacks as setbacks.” A month and change later, it’s done — these two posts are the delivery record. 1. What This Record … Read more

From Rules to a World: A C++ Runtime Verification of Procedural Terrain

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Revision note (2026-09-30): This article records work from 2026-07-13. Early proxy designs, sample measurements, and evidence about the original algorithm are distinguished below. Pending work retains its historical validation scope. Later progress is covered in heightmap reconstruction and POI, Stamp, vegetation, and rock layouts. — From a reverse-engineered generation model to pre-landing engineering verification AI-Assisted … Read more

Open-World Population Orchestration: Identity Before the Entity, Crowds Tiered by Distance

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Series The City That Runs Itself · Pedestrians · Scheduling Layer Previous (series overview): Rebuilding a City That Runs Itself in UE5. This article picks up from it, going deep on the crowd / population part. The traffic article covered how vehicle flow is scheduled. This one turns the lens to the crowds on the … Read more

Dynamic City | City Population Runtime (Part 1): World Foundation, Population Scheduling, and Perception–Decision

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This article is one of the deep-dive installments of the How to Build an Open-World Game series (the series overview, *A Systems Overview*, is here—reading it first is recommended for the big picture), focused on a single point deep enough to deserve its own piece: when a street has to keep hundreds of NPCs and … Read more