Core JavaScript

SVG - Shooting a Ball Animation

This JavaScript Reference section displays the code for an example program that shows how to animate the shooting of a ball using scalable vector graphics (SVG).

ShootingBall.html

<!DOCTYPE html>
<html>
<head>
  <title>XoaX.net's Javascript Shooting a Ball Animation</title>
  <script type="text/javascript" src="ShootingBall.js"></script>
  <button onclick="Restart()">Shoot</button>
</head>
<body>
</body>
</html>

ShootingBall.js

const kiTotalTime = 150;
var iTime = 0;
var qPosition = { mdX:50.0, mdY:400.0};
var qInitVelocity = { mdX:3.3, mdY:10};
var gqTranslationSvg = null;
var gbRunning = false;

function UpdatePosition() {
	// Change the position and translation
	qPosition.mdX += qInitVelocity.mdX;
	qPosition.mdY -= (qInitVelocity.mdY - 20*(iTime/kiTotalTime));
	gqTranslationSvg.setAttribute('transform', 'translate('+qPosition.mdX+', '+qPosition.mdY+')');
}

function AnimationLoop() {
  UpdatePosition();
  ++iTime;
  // Stop when the ball hits the ground
  if (qPosition.mdY < 400){
    setTimeout(AnimationLoop, 25);
  } else {
	gbRunning = false;
  }
}

function Restart() {
  if (!gbRunning) {
    qPosition.mdX = 50.0;
    qPosition.mdY = 400.0;
    iTime = 0;
    gbRunning = true;
    AnimationLoop();
  }
}

function Initialize() {
  qpBody = document.getElementsByTagName("body")[0];

  // Create a 600 by 400 pixel region for drawing
  qMainDiv = document.createElement('div');
  qpBody.appendChild(qMainDiv);
  qMainDiv.style.width = '600px';
  qMainDiv.style.height = '400px';
  qMainDiv.style.background = 'linear-gradient(cyan, tan)';

  // The Main SVG Element
  var qMainSvg = document.createElementNS("http://www.w3.org/2000/svg", "svg");
  qMainSvg.style.width="600px";
  qMainSvg.style.height="400px";
  qMainDiv.appendChild(qMainSvg);

  // Add a  SVG Translation Element
  gqTranslationSvg = document.createElementNS("http://www.w3.org/2000/svg", "g");
  qMainSvg.appendChild(gqTranslationSvg);
  gqTranslationSvg.setAttribute('transform', 'translate('+qPosition.mdX+', '+qPosition.mdY+')');

  // The SVG Ball Element
  var gqBallSvg = document.createElementNS("http://www.w3.org/2000/svg", "circle");
  gqTranslationSvg.appendChild(gqBallSvg);
  gqBallSvg.setAttribute('cx', 0);
  gqBallSvg.setAttribute('cy', 0);
  gqBallSvg.setAttribute('r', 4);
  gqBallSvg.setAttribute('fill', 'rgb(55, 55, 55)');
}

window.onload = Initialize;
 

Output

 
 

© 2007–2024 XoaX.net LLC. All rights reserved.