DrivingThrills — Harpreet Johal

Introduction

It’s a open world game highly optimized for mobile made at underdogs studio. The team consists of 1 Programmer, 1 Designer, 2-3 artists. As a Lead programmer of the project I was responsible for smooth gameplay, unique systems provided by the Designer with stable fps on mobile that challenged me to dig deep and come up with creative, optimized solutions. Running a project solo can be super tough with all kinds of challenges thrown your way—but hey, the reward makes it totally worth it. That said, I love working with a team... it’s just way more fun! to achieve something together who shares the same understanding.

Traffic System

A modular system that populates and manages AI vehicles along waypoint paths, adapting density and performance to user graphics settings.

Core Responsibilities:

Graphics-Driven Density
- It reads Settings.GraphicsIndex to Configurable MaxSpawnCount per quality level
Object Pooling
- Pre-instantiates VehicleAIs and stored them in vehiclePool and Reuses pooled vehicles when escaping
Waypoint-Based Spawning
- Finds all WaypointPath instances within MaxSpawnRadius of the player
- Samples their waypoints at intervals of spaceBetweenVehicles to evenly distribute spawns
- Computes spawn rotation from current → next waypoint for natural orientation
Player-Vehicle Interaction
- Removes a vehicle AI from the pool when the player enters via the OnPlayerEnterAiCar event
- On explosion of the vehicle AI, updates the pool to replenish traffic
Performance Culling
- To make sure traffic dosen't spawn in front of the player they only spawn far away or behind the player likewise vehicle AIs that wander out of range or fall behind the player after a set distance are despawned

Police System

In this system, players build up Wanted Stars (0 to 5) based on the crimes they commit. The more chaos you cause, the more stars you attract. Once your crime rate crosses a threshold, you earn a star—and with it comes trouble: sirens, police cars, and police NPCs chasing you down.
Only way out is to escape the police.

Tech Notes:

Event-Driven Architecture: It’s all powered by WantedStarSystem that tracks your wanted level and fires events when crime is committed such as OnWantedStarAdded(int wantedLevel) and OnResetWantedStar(). The WantedLevelManager ties it all together—handling crime thresholds, triggering police spawners, and cleaning up when you escape or get busted.
Object Pooling: performant instantiation using delays and recycling of police entities when escaping.
Adaptive Spawning:
- Singleton Persistence: Inherits from MonoBehaviourSingletonPersistentNoLoad for scene changes
- Coroutines for Smooth Performance: Delays in both spawning and death cleanup
- NavMesh SamplePosition: Spawn Police AIs at a random position in the navMesh area such as road to avoid overlaps on obstacle and gives clear paths to player.
- Player-View Exclusion: Simple dot-product trick keeps Ais spawning behind the player or at a far distance.

Others

There are others features like:

Clothes System (for wardrobe and shop)
Passenger Pick-and-Drop (for bus, auto rickshaw, etc.)
Tutorial System
Stunts (for bikes and 4 wheelers)
Cheat Systems using mobile phone (supports all vehicles)
Football Arena

and more…

Harpreet Johal

Driving Thrills

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