Concept
THROUGH means moving from one side of something to the other, passing inside or across its boundaries. This involves motion and the crossing of a barrier or boundary.
Translation Strategy
To create "through" relationships on screen:
- Boundary Crossing: Detect when an element crosses from one side of a barrier to another
- State Tracking: Track entry and exit from the barrier area
- Position-based Feedback: Use position to determine visual appearance
Key P5.js Methods
Coordinate System:
•
createCanvas(width, height) - Creates coordinate system where (0,0) is top-left
•
rect(x, y, width, height) - Draw rectangular barrier
Boundary Detection:
• Compare object position with barrier edges
•
dist(x1, y1, x2, y2) - Calculate distance from barriers
• Track which side of barrier the object is on
State Management:
• Use boolean flags to track entry and exit states
• Check if movement crosses from one side to another
Visual Feedback:
•
fill(r, g, b) - Change colors based on position and state
•
stroke(r, g, b) - Change border colors
•
ellipse(x, y, width, height) - Draw moving circle
Mouse Interaction:
•
mousePressed() - Detect when mouse is clicked
•
mouseDragged() - Detect when mouse is dragged
•
mouseReleased() - Detect when mouse is released
Code Structure
Basic Pattern for "Through":
1. Define barrier: Create rectangular boundary
let barrier = {x: 180, y: 50, width: 40, height: 200};
2. Track state: Monitor entry and exit
let movingCircle = {hasEnteredBarrier: false, hasExitedBarrier: false, hasPassed: false};
3. Check crossing: Detect complete traversal
if (isInsideBarrier && !hasEnteredBarrier) {
hasEnteredBarrier = true;
entryFromLeft = (x < barrier.x + barrier.width/2);
}
4. Position-based colors: Visual feedback based on location
if (isInsideBarrier) {
fill(255, 255, 100); // Yellow - passing through
} else if (x < barrier.center) {
fill(255, 150, 100); // Orange - left side
} else {
fill(100, 255, 100); // Green - right side
}