API tools faq
paste
Advertisement
Guest User

Don't click

a guest
Jul 19th, 2019
89
0
Never
Add comment
Not a member of Pastebin yet? Sign Up, it unlocks many cool features!
JavaScript 2.69 KB | None | 0 0
raw download clone embed print report
  1. //Bro I told u, don't click
  2. <!DOCTYPE html>
  3. <html>
  4.     <head>
  5.         <meta charset="utf-8"/>
  6.         <title>Balle rebondissante</title>
  7.     </head>
  8.     <body style="margin: 0px; overflow: hidden">
  9.        
  10.         <canvas id="canvas"></canvas>
  11.        
  12.         <script>
  13. var canvas  = document.getElementById("canvas"),
  14.     context = canvas.getContext("2d"),
  15.     width   = window.innerWidth,
  16.     height  = window.innerHeight,
  17.     ratio   = window.devicePixelRatio;
  18. canvas.width  = width  * ratio;
  19. canvas.height = height * ratio;
  20. canvas.style.width  = width  + "px";
  21. canvas.style.height = height + "px";
  22. context.scale(ratio, ratio);
  23. var gravity = 1,
  24.     radius = 20,
  25.     dt = 1,
  26.     mass = 1,
  27.     inertia = 100,
  28.     restit = 0.95,
  29.     grip = 1.8,
  30.     fric = 0.3;
  31. var x = 50,
  32.     y = 50,
  33.     o = 0,
  34.     vx = 12,
  35.     vy = 0,
  36.     vo = 0;
  37. animate();
  38. function animate() {
  39.     draw();
  40.     update();
  41.     requestAnimationFrame(animate);
  42. }
  43. function draw() {
  44.     context.clearRect(0, 0, width, height);
  45.    
  46.     context.beginPath();
  47.     context.moveTo(x, y);
  48.     context.arc(x, y, radius, o, o + 2*Math.PI);
  49.     context.stroke();
  50. }
  51. function update() {
  52.     applyForce(0, mass * gravity, 0, 0);
  53.     x += vx * dt;
  54.     y += vy * dt;
  55.     o += vo * dt;
  56.    
  57.    
  58.     if (x < radius) {
  59.         x = radius;
  60.         generateContactForce(1, 0);
  61.     }
  62.    
  63.     if (x > width - radius) {
  64.         x = width - radius;
  65.         generateContactForce(-1, 0);
  66.     }
  67.    
  68.     if (y < radius) {
  69.         y = radius;
  70.         generateContactForce(0, 1);
  71.     }
  72.    
  73.     if (y > height - radius) {
  74.         y = height - radius;
  75.         generateContactForce(0, -1);
  76.     }
  77. }
  78. function applyForce(fx, fy, cx, cy) {
  79.     var torque = -fx * cy + fy * cx,
  80.        
  81.         ax = fx / mass,
  82.         ay = fy / mass,
  83.         ao = torque / inertia;
  84.    
  85.     vx += ax * dt;
  86.     vy += ay * dt;
  87.     vo += ao * dt;
  88. }
  89. function generateContactForce(nx, ny) {
  90.     var tx, ty, vNormal, vTangent, vContact, fNormal, fTangent, fTangentMax, fx, fy;
  91.    
  92.     tx = -ny;
  93.     ty =  nx;
  94.    
  95.     vNormal  = vx * nx + vy * ny;
  96.     vTangent = vx * tx + vy * ty;
  97.     vContact = vTangent - vo * radius;
  98.    
  99.     fNormal  = -(1 + restit) * vNormal * mass / dt;
  100.     fTangent = - grip * vContact / (1/mass + radius*radius/inertia) / dt;
  101.     fTangentMax = fric * fNormal;
  102.    
  103.     if (fTangent > fTangentMax) {
  104.         fTangent = fTangentMax;
  105.     }
  106.     if (fTangent < -fTangentMax) {
  107.         fTangent = -fTangentMax;
  108.     }
  109.    
  110.     fx = fNormal * nx + fTangent * tx;
  111.     fy = fNormal * ny + fTangent * ty;
  112.    
  113.     applyForce(fx, fy, -nx * radius, -ny * radius);
  114. }
  115.         </script>
  116.        
  117.     </body>
  118. </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!