trajectory

by John kuoppala

HTML

<canvas id="canvas"></canvas>

CSS

canvas {
    border: 1px solid black;
}

JavaScript

var c = document.getElementById("canvas");
var ctx = c.getContext("2d");

c.width = 400;
c.height = 400;

var x = 0;
var y = 400;
var oldX = 0;
var oldY = 400;
var xVel = 10;
var yVel = -20;
var g = 1;


var myInterval = setInterval(function () {
                               x+=xVel;
                               y+=yVel;
                               yVel+=g;
                               ctx.beginPath();
                               ctx.moveTo(oldX,oldY);
                               ctx.lineTo(x,y);
                               ctx.stroke();
                               oldX = x;
                               oldY = y;
                             },20);