Grand Auto Thief

Grand Auto Thief - Complete Game Description

Grand Auto Thief is a 100% offline, browser-based open-world action game inspired by classic Grand Theft Auto, built entirely from scratch using HTML5 Canvas and JavaScript. Created by happystoner5420 Games, it's a complete GTA-style experience with no external assets - every sprite, sound, and texture is procedurally generated in real-time.

Core Gameplay

You're a criminal loose in a procedurally generated city spanning 80x80 blocks (5,120 pixels squared). Your goal is simple: survive, steal, fight, get rich, and own the city. Commit crimes to earn cash from pedestrians and vehicles, then spend it at the gun store to arm yourself with increasingly powerful weapons.

Open World Features

Dynamic City Districts:

Downtown: Dense high-rises (6-14 floors) forming the urban core

Commercial: Mid-rise shops and offices with rooftop AC units

Suburbs: Single-family houses with lawns and trees

Industrial: Warehouses and shipping containers

Park: Green space with trees and a pond

Waterfront: Ocean edge along the map border

Living City Systems:

Full traffic simulation with AI-controlled vehicles following lanes, stopping at red lights, yielding at intersections, and car-following behavior

60+ pedestrians wandering sidewalks, idling, chatting, and fleeing from danger

Dynamic day/night cycle (160 seconds per full day)

Weather system: clear, cloudy, rain, and storm with animated raindrops

Procedurally placed street lamps that glow at night

Crosswalks, sidewalks, and realistic road markings

Combat & Weapons

Arsenal Available at the Gun Store:

Fists: Your starting weapon (12 damage, melee only)

Pistol: Semi-auto sidearm ($350, 24 damage, 12-round mag)

Uzi: Rapid-fire SMG ($1,600, 13 damage, 32-round mag, high spread)

SMG: Balanced submachine gun ($900, 15 damage, 30-round mag)

Machine Gun: Heavy automatic ($2,400, 18 damage, 80-round mag)

Shotgun: Close-range devastation ($1,300, 12 damage x6 pellets, 6-round mag)

Rifle: Long-range precision ($2,200, 42 damage, 20-round mag, minimal spread)

Each weapon has realistic mechanics including magazine capacity, reload times, fire rates, damage falloff, and bullet spread. Police cruisers contain shotguns you can loot after carjacking them.

Vehicle System

13 Vehicle Types:

Sedan, Sports Car, Supercar, SUV, Pickup, Van

Taxi, Police Cruiser, Ambulance, Fire Truck

Bus, Semi Truck with trailer, Motorcycle

Driving Features:

Realistic acceleration, braking, and steering physics

Handbrake drifting (spacebar)

Speed-dependent handling and camera zoom

Vehicle damage system (shoot cars to destroy them)

Working headlights and brake lights

Procedural engine audio that changes with RPM

Drive-by shooting while in vehicles

Carjacking mechanics - steal any parked or moving vehicle

Wanted System (GTA-Style)

5-Star Police Response:

Crimes witnessed by police count double

Each wanted star spawns police cruisers that pursue you

Police use advanced chase AI: ramming, shooting, coordinating with other units

On-foot officers continue fighting if thrown from vehicles

Bust system: officers drag you from your car after 1.6 seconds, confiscating weapons and $200

Stars decay one at a time after 6 seconds of avoiding trouble

Crimes That Raise Wanted Level:

Shooting/killing pedestrians (~3 kills = 1 star)

Stealing vehicles (0.2 stars per car, 0.5 for police vehicles)

Carjacking cops (0.5 stars)

Destroying vehicles (0.4 stars)

Shooting firearms in public (0.06 per shot)

Player Mechanics

Movement:

8-directional WASD/arrow key movement

Sprint with Shift (increases speed from 155 to 235 units/sec)

Realistic walk animation with swinging arms and alternating legs

Footstep sound effects

Vehicle entry/exit (E key)

Combat:

Mouse aim (8-directional character facing)

Left-click to shoot/punch

Real-time reload system (R key or auto-reload on empty)

Weapon switching with number keys 1-9

Blood splatter and corpse physics

Ragdoll death animations

Stats:

Health (100 HP) with slow auto-regen after 5 seconds out of combat

Armor (absorbs 60% damage until depleted)

Money (start with $500, loot from killed NPCs)

8 weapon slots with individual ammo pools

Visual & Audio Design

Graphics:

Fully procedural 2D top-down graphics (no sprite sheets)

Buildings pre-rendered with realistic metallic gradients, glass reflections, and rooftop details

Vehicles drawn with body shadows, chrome trim, working lights, and reflective windshields

Humans rendered per-frame with skin tones, clothing colors, and animated walk cycles

Particle effects: blood splatter, bullet tracers, muzzle flashes, sparks, smoke, explosions

Blood decals that persist on the ground

Day/night lighting with warm dawn/dusk tints

Screen shake on explosions and crashes

Damage flash and low-health vignette

Cinematic camera with smooth following and zoom

Audio (100% Procedural via Web Audio API):

Gunshots with unique sounds per weapon type

Procedural engine hum that revs with speed

Explosions, crashes, sirens

Reload clicks, footsteps, punches, cash pickups

Ambient rain noise that scales with weather intensity

All audio generated in real-time (no audio files)

HUD & Interface

In-Game HUD:

Health bar (green → yellow → red as it depletes)

Armor bar (blue, shows when equipped)

Cash counter with live updates

Circular minimap showing: terrain, buildings, vehicles, gun store icon, player cone of view

Wanted stars (5-star display at top-center)

Arrest progress bar when police are dragging you out

Weapon name, ammo count, and reload status

Weapon slot indicators (1-9)

Time of day + weather icon

Interaction prompts ("Press E to steal vehicle", "Press E to enter Gun Store")

Crosshair when armed

Menus:

Main Menu: New Game, Continue, How to Play, Credits, Exit

Pause Menu (ESC/P): Resume, Save Game, Return to Main Menu

Gun Store: Buy weapons and refill ammo (owned weapons cost 50% to refill)

Game Over Screen: Respawn for $100

Busted Screen: Respawn with weapons confiscated and $200 fine

Progression & Economy

Start with $500 and fists only

Kill NPCs to collect cash pickups ($5-$60 per pedestrian)

Visit the gun store (marked with a giant handgun sign on rooftops)

Buy progressively better weapons

Steal faster vehicles to outrun police

Death costs $100, getting busted costs $200 + all weapons

Save/load system using browser localStorage

Technical Features

Streaming world population (entities spawn/despawn based on distance)

Collision detection: player vs vehicles, vehicles vs vehicles, bullets vs entities

Line-of-sight raycasting for shooting and AI awareness

Traffic light system at intersections

Vehicle-pedestrian collision with ragdoll physics

Persistent blood decals and explosion craters

60 FPS game loop with delta-time physics

Responsive canvas that scales to window size

No external dependencies - runs entirely offline

Advanced AI Behaviors

Pedestrian AI:

Walk to random sidewalk destinations

Idle and chat with nearby NPCs

Flee from gunfire and explosions

Drop money on death

Police officers pursue on foot and engage in shootouts

Traffic AI:

Lane-following with proper road positioning

Intersection right-of-way yielding

Red light stopping at crosswalks

Car-following distance maintenance

Turning decisions at intersections

Police AI:

Chase mode with line-of-sight tracking

Ram-and-backup cycle to box in the player

Coordinated swarming with separation steering

Searching last-seen position when losing sight

Giving up chase and returning to patrol after losing the player for 15 seconds

Drive-by shooting at 3+ wanted stars

On-foot arrest attempts

Atmosphere & Polish

Cinematic camera shake on impacts

Soft ground shadows under all entities

Procedural car colors (15+ color palette)

Randomized pedestrian appearances (skin tones, clothing)

Neon glow around gun store at night

Street lamp halos in darkness

Rain that accelerates and drifts with wind

Sunrise/sunset color grading

Police cruiser lightbars

Taxi roof signs

Semi-truck articulated trailers

Motorcycle with visible rider

Toast notifications for pickups and purchases

Grand Auto Thief is an impressive technical achievement - a fully functional GTA-style game running entirely in the browser with zero external assets, demonstrating advanced game programming techniques in procedural generation, AI pathfinding, physics simulation, and audio synthesis. It's a complete sandbox crime simulator that captures the essence of the GTA experience in a lightweight, 100% offline package.