API tools faq
paste
Advertisement
here2share

$ JS_cloth_sim.html

here2share
Dec 17th, 2022
832
0
Never
Add comment
Not a member of Pastebin yet? Sign Up, it unlocks many cool features!
JavaScript 4.28 KB | None | 0 0
raw download clone embed print report
  1. <!DOCTYPE html>
  2. <html>
  3. <head>
  4.   <title>Stretchy Cloth Simulation</title>
  5. </head>
  6. <body>
  7.   <canvas id="clothCanvas" width="600" height="400"></canvas>
  8.   <button id="resetButton">Reset</button>
  9.   <script>
  10.     // Get canvas and context
  11.     const canvas = document.getElementById('clothCanvas');
  12.     const ctx = canvas.getContext('2d');
  13.  
  14.     // Set up cloth properties
  15.     const clothWidth = 50;
  16.     const clothHeight = 10;
  17.     const clothSpacing = 10;
  18.     const clothStiffness = 0.1;
  19.     const clothDamping = 0.98;
  20.     const clothMass = 1;
  21.     const gravity = 0.1;
  22.  
  23.     // Set up cloth points and constraints
  24.     let points = [];
  25.     let constraints = [];
  26.     for (let y = 0; y <= clothHeight; y++) {
  27.       for (let x = 0; x <= clothWidth; x++) {
  28.         let point = {
  29.           x: x * clothSpacing,
  30.           y: y * clothSpacing,
  31.           oldX: x * clothSpacing,
  32.           oldY: y * clothSpacing,
  33.           pinned: (x === 0 && y === 0) || (x === clothWidth && y === 0),
  34.           mass: clothMass
  35.         };
  36.         points.push(point);
  37.         if (x > 0) {
  38.           constraints.push({
  39.             pointA: points[points.length - 1],
  40.             pointB: points[points.length - 2],
  41.             length: clothSpacing,
  42.             stiffness: clothStiffness
  43.           });
  44.         }
  45.         if (y > 0) {
  46.           constraints.push({
  47.             pointA: points[points.length - 1],
  48.             pointB: points[points.length - clothWidth - 1],
  49.             length: clothSpacing,
  50.             stiffness: clothStiffness
  51.           });
  52.         }
  53.       }
  54.     }
  55.  
  56.     // Set up mouse interaction
  57.     let dragging = false;
  58.     let dragPoint;
  59.     canvas.addEventListener('mousedown', e => {
  60.       let rect = canvas.getBoundingClientRect();
  61.       let x = e.clientX - rect.left;
  62.       let y = e.clientY - rect.top;
  63.       points.forEach(point => {
  64.         if (Math.abs(point.x - x) < clothSpacing && Math.abs(point.y - y) < clothSpacing) {
  65.           dragPoint = point;
  66.           dragging = true;
  67.         }
  68.       });
  69.     });
  70.     canvas.addEventListener('mousemove', e => {
  71.       if (dragging) {
  72.         let rect = canvas.getBoundingClientRect();
  73.         let x = e.clientX - rect.left;
  74.         let y = e.clientY - rect.top;
  75.         dragPoint.x = x;
  76.         dragPoint.y = y;
  77.       }
  78.     });
  79.     canvas.addEventListener('mouseup', () => {
  80.       dragging = false;
  81.       dragPoint = null;
  82.     });
  83.     canvas.addEventListener('contextmenu', e => {
  84.       e.preventDefault();
  85.       if (dragPoint) {
  86.     dragPoint.pinned = !dragPoint.pinned;
  87.       }
  88.     });
  89. // Set up reset button
  90. const resetButton = document.getElementById('resetButton');
  91. resetButton.addEventListener('click', () => {
  92.   points.forEach(point => {
  93.     point.x = point.oldX;
  94.     point.y = point.oldY;
  95.   });
  96. });
  97.  
  98. // Set up animation loop
  99. function animate() {
  100.   // Update points
  101.   points.forEach(point => {
  102.     if (!point.pinned) {
  103.       let velocityX = (point.x - point.oldX) * clothDamping;
  104.       let velocityY = (point.y - point.oldY) * clothDamping;
  105.       point.oldX = point.x;
  106.       point.oldY = point.y;
  107.       point.x += velocityX;
  108.       point.y += velocityY + gravity;
  109.     }
  110.   });
  111.  
  112.   // Satisfy constraints
  113.   constraints.forEach(constraint => {
  114.     let pointA = constraint.pointA;
  115.     let pointB = constraint.pointB;
  116.     let length = constraint.length;
  117.     let stiffness = constraint.stiffness;
  118.  
  119.     let dx = pointB.x - pointA.x;
  120.     let dy = pointB.y - pointA.y;
  121.     let distance = Math.sqrt(dx * dx + dy * dy);
  122.     let difference = length - distance;
  123.     let percentage = difference / distance / 2;
  124.     let offsetX = dx * percentage;
  125.     let offsetY = dy * percentage;
  126.     if (!pointA.pinned) {
  127.       pointA.x -= offsetX;
  128.       pointA.y -= offsetY;
  129.     }
  130.     if (!pointB.pinned) {
  131.       pointB.x += offsetX;
  132.       pointB.y += offsetY;
  133.     }
  134.   });
  135.  
  136.   // Draw cloth
  137.   ctx.clearRect(0, 0, canvas.width, canvas.height);
  138.   ctx.beginPath();
  139.   points.forEach(point => {
  140.     ctx.lineTo(point.x, point.y);
  141.   });
  142.   ctx.stroke();
  143.   ctx.closePath();
  144.  
  145.   // Draw points
  146.   ctx.fillStyle = 'red';
  147.   points.forEach(point => {
  148.     ctx.beginPath();
  149.     ctx.arc(point.x, point.y, clothSpacing / 2, 0, 2 * Math.PI);
  150.     ctx.fill();
  151.   });
  152.  
  153.   requestAnimationFrame(animate);
  154. }
  155.  
  156. animate();
  157. </script>
  158. </body>
  159. </html>
Advertisement
Add Comment
Please, Sign In to add comment
Advertisement
Public Pastes
Advertisement
We use cookies for various purposes including analytics. By continuing to use Pastebin, you agree to our use of cookies as described in the Cookies Policy.  OK, I Understand
Not a member of Pastebin yet?
Sign Up, it unlocks many cool features!