How to make a sprite move left and right in the direction it's pointing

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MovementMaster_Dev

Posted on March 1, 2025 • Intermediate

🎮 Need help with directional sprite movement

Hey everyone! I’m working on a game where I need my sprite to move in different directions based on where it’s pointing. I’ve got basic movement working with XVel and YVel, but I can’t figure out how to make the sprite move left and right relative to its current facing direction.

Currently I have this setup for basic movement:

W/S keys for forward/backward movement
A/D keys for left/right movement (but only in world coordinates)
Q/E keys for rotation

The problem is that when my sprite rotates, the left/right movement doesn’t follow the sprite’s orientation. How can I make the sprite move sideways relative to where it’s facing? 🤔

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ScratchCoder_Expert

Replied 20 minutes later • ⭐ Best Answer

Great question @MovementMaster_Dev! This is a common challenge when working with directional movement. Here’s the solution using the “move” block with temporary rotation:

🎯 Directional Movement Flow

Here’s how directional movement works in Scratch:

flowchart TD A[🎮 Key Pressed] --> B{Which Key?} B -->|W Key| C[Move Forward] B -->|S Key| D[Move Backward] B -->|A Key| E[Move Left] B -->|D Key| F[Move Right] B -->|Q Key| G[Turn Left] B -->|E Key| H[Turn Right] C --> C1[move (speed) steps] D --> D1[move (0 - speed) steps] E --> E1[turn ccw (90) degrees] E1 --> E2[move (speed) steps] E2 --> E3[turn cw (90) degrees] F --> F1[turn cw (90) degrees] F1 --> F2[move (speed) steps] F2 --> F3[turn ccw (90) degrees] G --> G1[turn ccw (15) degrees] H --> H1[turn cw (15) degrees] C1 --> I[Continue Game Loop] D1 --> I E3 --> I F3 --> I G1 --> I H1 --> I style A fill:#e1f5fe style E1 fill:#fff3e0 style E2 fill:#e8f5e8 style E3 fill:#fff3e0 style F1 fill:#fff3e0 style F2 fill:#e8f5e8 style F3 fill:#fff3e0

🔧 Complete Movement System

Here’s the complete code for directional movement:

    when flag clicked
set [Speed v] to [5]
forever
// Forward movement
if <key [w v] pressed?> then
move (Speed) steps
end

// Backward movement
if <key [s v] pressed?> then
move ((0) - (Speed)) steps
end

// Left strafe movement
if <key [a v] pressed?> then
turn ccw (90) degrees
move (Speed) steps
turn cw (90) degrees
end

// Right strafe movement
if <key [d v] pressed?> then
turn cw (90) degrees
move (Speed) steps
turn ccw (90) degrees
end

// Rotation controls
if <key [q v] pressed?> then
turn ccw (15) degrees
end

if <key [e v] pressed?> then
turn cw (15) degrees
end
end

💡 How It Works

The key insight is using temporary rotation for sideways movement:

Forward/Backward: Use move (speed) steps directly
Left Movement: Turn 90° left, move forward, turn 90° right back
Right Movement: Turn 90° right, move forward, turn 90° left back

This happens so fast that the player only sees the sideways movement, not the rotation!

🚀 Advanced Version with Smooth Movement

For even smoother movement, you can use variables to track movement separately:

    when flag clicked
set [Speed v] to [5]
set [Forward v] to [0]
set [Strafe v] to [0]

forever
// Check input
set [Forward v] to [0]
set [Strafe v] to [0]

if <key [w v] pressed?> then
change [Forward v] by (Speed)
end
if <key [s v] pressed?> then
change [Forward v] by ((0) - (Speed))
end
if <key [a v] pressed?> then
change [Strafe v] by ((0) - (Speed))
end
if <key [d v] pressed?> then
change [Strafe v] by (Speed)
end

// Apply movement
if <not <(Forward) = [0]>> then
move (Forward) steps
end

if <not <(Strafe) = [0]>> then
turn cw (90) degrees
move (Strafe) steps
turn ccw (90) degrees
end

// Rotation
if <key [q v] pressed?> then
turn ccw (3) degrees
end
if <key [e v] pressed?> then
turn cw (3) degrees
end
end

This version allows for diagonal movement when multiple keys are pressed! 🎮

👍 Like (52)💬 Reply 🏆 Mark as Best Answer

MovementMaster_Dev

Replied 3 hours later

@ScratchCoder_Expert This is exactly what I needed! Thank you so much! 🎉

The temporary rotation trick is brilliant - I never would have thought of that. The movement feels perfect now and my sprite moves exactly how I wanted it to!

👍 Like (15)💬 Reply

GameMechanics_Pro

Replied 1 day later

Great solution! Just wanted to add a few tips for anyone implementing this: