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Debugging mouse tracking and clone creation issues

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DM

DebugMaster_Alex

Posted on February 5, 2024 • Intermediate

🐛 Mouse tracking code not working properly

Hey everyone! I’m trying to create a mouse tracking system that creates clones when the mouse moves, but it’s not working as expected. Here’s what I’m trying to achieve:

  • Track mouse movement accurately
  • Create clones when the mouse position changes
  • Have smooth visual effects following the cursor

My current code has complex position calculations that don’t seem to work correctly. The clones aren’t being created when I move the mouse. Can someone help me debug this? 🙏

CD

CodeDetective_Sarah

Replied 3 hours later • ⭐ Best Answer

Great debugging question @DebugMaster_Alex! I can see the issue with your code. The problem is in the complex position calculations and logic flow. Here’s a complete solution with proper debugging techniques:

🔍 Debugging Process Flow

Here’s how to systematically debug mouse tracking issues:

flowchart TD A[🚀 Start Debugging] --> B[Identify the Problem] B --> C[Analyze Current Code] C --> D[Check Position Logic] D --> E[Test Mouse Detection] E --> F[Verify Clone Creation] F --> G[Test Visual Effects] D --> H{Position Correct?} H -->|No| I[Fix Position Calculation] H -->|Yes| J[Check Next Component] E --> K{Mouse Detected?} K -->|No| L[Fix Mouse Tracking] K -->|Yes| M[Check Clone Logic] F --> N{Clones Created?} N -->|No| O[Fix Clone Conditions] N -->|Yes| P[Check Visual Effects] I --> Q[Simplified Solution] L --> Q O --> Q Q --> R[🎯 Working System] style A fill:#e1f5fe style B fill:#f3e5f5 style Q fill:#e8f5e8 style R fill:#fff3e0

🔧 Problem Analysis

The original code has several issues:

  • Overcomplicated position tracking: Adding 3000 to coordinates is unnecessary
  • Complex condition logic: The OR condition with negation is confusing
  • No movement detection: The code doesn’t properly detect when the mouse moves
  • Performance issues: Creating clones every frame without proper throttling

✅ Simple and Effective Solution

Here’s a clean, working mouse tracking system:

    // Main mouse tracking script
when flag clicked
set [last mouse x v] to (mouse x)
set [last mouse y v] to (mouse y)
set [trail enabled v] to [true]

forever
if <(trail enabled) = [true]> then
// Check if mouse has moved
if <not <<(mouse x) = (last mouse x)> and <(mouse y) = (last mouse y)>>> then
// Mouse moved, create trail effect
create clone of [myself v]

// Update last known position
set [last mouse x v] to (mouse x)
set [last mouse y v] to (mouse y)

// Small delay to control clone creation rate
wait [0.05] seconds
end
end
end

🌟 Enhanced Mouse Trail System

For better visual effects and performance:

    // Advanced mouse trail with distance threshold
when flag clicked
set [last mouse x v] to (mouse x)
set [last mouse y v] to (mouse y)
set [min distance v] to [10]  // Minimum distance before creating clone
set [trail color v] to [0]

forever
// Calculate distance moved
set [distance moved v] to ([sqrt v] of (((([abs v] of ((mouse x) - (last mouse x))) ^ [2]) + (([abs v] of ((mouse y) - (last mouse y))) ^ [2])))

if <(distance moved) > (min distance)> then
// Create trail clone
create clone of [myself v]

// Update position tracking
set [last mouse x v] to (mouse x)
set [last mouse y v] to (mouse y)

// Cycle through colors
change [trail color v] by [10]
if <(trail color) > [200]> then
set [trail color v] to [0]
end
end
end

🎨 Clone Behavior System

How clones should behave when created:

    when I start as a clone
// Position clone at mouse location
go to x: (mouse x) y: (mouse y)

// Set visual properties
set [color v] effect to (trail color)
set size to [100] %
show

// Fade out animation
repeat [20]
change size by [-4]
change [ghost v] effect by [5]
wait [0.05] seconds
end

// Clean up
delete this clone

🎮 User Control Features

Add interactive controls for better user experience:

    // Toggle trail on/off
when [space v] key pressed
if <(trail enabled) = [true]> then
set [trail enabled v] to [false]
say [Trail OFF] for [1] seconds
else
set [trail enabled v] to [true]
say [Trail ON] for [1] seconds
end

// Adjust trail sensitivity
when [up arrow v] key pressed
change [min distance v] by [-2]
if <(min distance) < [2]> then
set [min distance v] to [2]
end
say (join [Sensitivity: ] (min distance)) for [1] seconds

when [down arrow v] key pressed
change [min distance v] by [2]
if <(min distance) > [50]> then
set [min distance v] to [50]
end
say (join [Sensitivity: ] (min distance)) for [1] seconds

// Clear all clones
when [c v] key pressed
broadcast [clear all clones v]

when I receive [clear all clones v]
if <(clone id) > [0]> then
delete this clone
end

🚀 Performance Optimization

For smooth performance with many clones:

    // Clone limit system
when flag clicked
set [max clones v] to [50]
set [clone count v] to [0]

// Modified clone creation with limit
define create trail clone
if <(clone count) < (max clones)> then
create clone of [myself v]
change [clone count v] by [1]
else
// Remove oldest clone by broadcasting cleanup
broadcast [remove oldest clone v]
wait [0.01] seconds
create clone of [myself v]
end

// Clone cleanup system
when I start as a clone
set [clone id v] to (clone count)
set [clone age v] to [0]

forever
change [clone age v] by [1]
if <(clone age) > [200]> then  // Auto-delete after 200 frames
change [clone count v] by [-1]
delete this clone
end
end

when I receive [remove oldest clone v]
if <(clone age) > [150]> then  // Remove if old enough
change [clone count v] by [-1]
delete this clone
end

💡 Debugging Tips

  • Start simple: Begin with basic mouse following, then add features
  • Use say blocks: Display variable values to debug position tracking
  • Test incrementally: Add one feature at a time and test
  • Check conditions: Make sure your if statements are logically correct
  • Monitor performance: Watch for lag when creating many clones

The key is keeping the logic simple and readable. Complex calculations often introduce bugs that are hard to find! 😊

DM

DebugMaster_Alex

Replied 2 hours later

@CodeDetective_Sarah This is absolutely perfect! Thank you so much! 🎉

The simplified approach works flawlessly. I can’t believe I was overcomplicating it so much. The debugging process you outlined is really helpful too. One question - how can I make the trail effect look more like a smooth line?

VE

VisualEffects_Maya

Replied 1 hour later

@DebugMaster_Alex For smooth line effects, try interpolating between positions:

    // Smooth line trail effect
define create smooth trail
set [steps v] to [5]
set [step x v] to (((mouse x) - (last mouse x)) / (steps))
set [step y v] to (((mouse y) - (last mouse y)) / (steps))

repeat (steps)
set [trail x v] to ((last mouse x) + ((step x) * (counter)))
set [trail y v] to ((last mouse y) + ((step y) * (counter)))
create clone of [trail dot v]
change [counter v] by [1]
end

This creates multiple points between mouse positions for a smoother line! ✨

VB

Vibelf_Community

Pinned Message • Moderator

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