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Need help creating traffic system for my game

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CB

CodeBuilder88

Posted on July 28, 2025 • Intermediate

🚗 Need help with traffic system implementation

Hey everyone! I’m working on a city simulation game and I want to create a realistic traffic system. I’ve got the basic road layout done, but I’m struggling with:

  • Making cars move along the roads properly
  • Implementing traffic lights that actually work
  • Preventing cars from crashing into each other
  • Creating different types of vehicles

I’ve already set up some basic scripts but they’re not working as expected. Any help would be greatly appreciated! 🙏

Project link: My Traffic Game Project

TS

TrafficSimulator_Pro

Replied 22 minutes later • ⭐ Best Answer

Great project idea @CodeBuilder88! Traffic systems can be tricky but super rewarding. Here’s a comprehensive guide to help you build an awesome traffic simulation:

🚦 Traffic System Architecture

Here’s how a good traffic system should work:

flowchart TD A[🚀 Game Start] --> B[Initialize Roads & Intersections] B --> C[Spawn Vehicles] C --> D[🚗 Vehicle Movement Loop] D --> E{Check Ahead} E -->|Clear Path| F[Move Forward] E -->|Traffic Light| G{Light Status?} E -->|Other Vehicle| H{Safe Distance?} G -->|Green| F G -->|Red/Yellow| I[Stop at Line] H -->|Yes| F H -->|No| J[Slow Down/Stop] F --> K[Update Position] I --> L[Wait for Green] J --> M[Maintain Safe Distance] K --> N{Reached Destination?} L --> G M --> H N -->|Yes| O[Remove Vehicle] N -->|No| D O --> P[Spawn New Vehicle] P --> D style A fill:#e1f5fe style B fill:#f3e5f5 style F fill:#e8f5e8 style I fill:#fff3e0 style O fill:#fce4ec

🛣️ Step 1: Road System Setup

First, create invisible path sprites that define where vehicles can move:

    when flag clicked
set [road width v] to [20]
set [lane count v] to [2]
go to x: [0] y: [0]
point in direction [90]
pen down
set pen size to (road width)
set pen color to [#808080]
repeat [10]
move [50] steps
end
pen up

🚗 Step 2: Vehicle Movement System

Create a car sprite with smart movement logic:

    when flag clicked
set [speed v] to [3]
set [max speed v] to [5]
set [following distance v] to [30]
forever
// Check for obstacles ahead
if <(distance to [nearest car v]) > (following distance)> then
if <(speed) < (max speed)> then
change [speed v] by [0.2]
end
else
if <(speed) > [0]> then
change [speed v] by [-0.5]
end
end

// Move forward
move (speed) steps

// Check if reached end of road
if <(x position) > [240]> then
go to x: [-240] y: (y position)
set [speed v] to [3]
end
end

🚦 Step 3: Traffic Light System

Create traffic lights that control vehicle flow:

    when flag clicked
set [light state v] to [green]
set [green time v] to [180] // 3 seconds at 60 FPS
set [yellow time v] to [60]  // 1 second
set [red time v] to [120]    // 2 seconds
set [timer v] to [0]

forever
change [timer v] by [1]

if <(light state) = [green]> then
set [color v] effect to [0]
if <(timer) > (green time)> then
set [light state v] to [yellow]
set [timer v] to [0]
end
else
if <(light state) = [yellow]> then
set [color v] effect to [25]
if <(timer) > (yellow time)> then
set [light state v] to [red]
set [timer v] to [0]
end
else
set [color v] effect to [50]
if <(timer) > (red time)> then
set [light state v] to [green]
set [timer v] to [0]
end
end
end
end

🔍 Step 4: Collision Detection

Add smart collision avoidance:

    define check ahead
set [can move v] to [true]

// Create invisible sensor in front of car
go to x: ((x position) + [30]) y: (y position)
if <touching [car v]?> then
set [can move v] to [false]
end

// Check traffic light
if <touching [traffic light v]?> then
if <(light state) = [red]> then
set [can move v] to [false]
end
if <(light state) = [yellow]> then
if <(distance to [traffic light v]) < [40]> then
set [can move v] to [false]
end
end
end

// Return to car position
go to x: (x position) y: (y position)

🚙 Step 5: Multiple Vehicle Types

Create different vehicle behaviors:

    when flag clicked
if <(vehicle type) = [car]> then
set [max speed v] to [4]
set [acceleration v] to [0.3]
else
if <(vehicle type) = [truck]> then
set [max speed v] to [2]
set [acceleration v] to [0.1]
else
if <(vehicle type) = [bus]> then
set [max speed v] to [3]
set [acceleration v] to [0.2]
set [following distance v] to [40]
end
end
end

🎯 Step 6: Advanced Features

Make your traffic system even more realistic:

Lane Changing:

    define try change lane
if <(speed) < [1]> then
if <not <touching [car v]?>> then
if <(lane) = [1]> then
change y by [20]
set [lane v] to [2]
else
change y by [-20]
set [lane v] to [1]
end
end
end

Emergency Vehicles:

    when I receive [emergency vehicle approaching v]
if <(vehicle type) = [ambulance]> then
set [max speed v] to [8]
broadcast [clear the way v]
else
// Regular cars move aside
if <(lane) = [1]> then
change y by [15]
wait [3] seconds
change y by [-15]
end
end

This should give you a solid foundation for your traffic system! The key is to start simple and gradually add more features. Good luck with your project! 🚗💨

CB

CodeBuilder88

Replied 45 minutes later

@TrafficSimulator_Pro This is absolutely amazing! Thank you so much! 🎉

I implemented the basic vehicle movement and it’s working perfectly. The collision detection is exactly what I needed. One quick question - how do I make the cars spawn randomly instead of all at once?

VB

Vibelf_Community

Pinned Message • Moderator

🚀 Ready to Build Advanced Simulations?

Fantastic discussion! For those interested in creating even more sophisticated traffic and simulation systems, our community can help you implement:

  • 🏙️ Complex city layouts
  • 🚌 Public transportation systems
  • 🚨 Emergency response scenarios
  • 📊 Traffic flow analytics

📚 Related Topics

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