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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

HTML

              
                <html lang="en">
<head>
  <meta charset="utf-8" >
  <title>Test HTML5 Canvas API</title>
  <style>
    #myCanvas {
    //  border: 1px solid black;
    }
  </style>
</head>
<body>

  <canvas id="myCanvas" height="600" width="1600">Canvas is not supported</canvas>
</body>
</html>
              
            
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CSS

              
                
              
            
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JS

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

var width = canvas.width;
var height = canvas.height;

function line (x1,y1,x2,y2,col) {
  if (col != undefined) {
    ctx.strokeStyle = col;
  }
  ctx.beginPath();  
  ctx.moveTo(x1,y1);
  ctx.lineTo(x2,y2);
  ctx.stroke();
}

var axisW = width * 0.95;

function d2x(d) {
  return (d+90)/180 * axisW - axisW/2 + width/2;
}

function radians(d) {
  return Math.PI * d / 180.0;
}

var base_y = 0.9 * height;

// X Axis
line (d2x(-90),base_y,d2x(90),base_y)

for (var d =-90;d<=90;d+=10) {
  var x = d2x(d);
  line ( x,base_y,x,base_y+10,"#4040FF" );
  ctx.font = "15px Arial";
  ctx.textAlign = "center";
  ctx.fillText(""+d+"°",x,base_y+23);
}

for (var d =-90;d<=90;d+=1) {
  var x = d2x(d);
  line ( x,base_y,x,base_y+4,"#4040FF" );
}
// Y- axis


var mid = d2x(0);

// Y axis
line (mid,base_y,mid,-height,"#C0C0C0")

// calculate miles per pixel
var mpp = 24901.0/2/axisW;
console.log(mpp);
for (var h=200;h<=4000;h+=200) {
  var yh = h/mpp;
  line (d2x(-90),base_y-yh,d2x(90),base_y-yh,"#E8E8E8")
  line (mid,base_y-yh,mid-10,base_y-yh,"#000000");
  ctx.textAlign = "right";
  ctx.fillText(""+h,mid-12,base_y-yh+5);
}



function SunLine(d) {
  var l = 1500;
  var dx = l * Math.sin(radians(d));
  var dy = l * Math.cos(radians(d));
  var x = d2x(d);
  var y = base_y
  line ( x, y, x-dx, y-dy, "#000000"); 
  
}

if (false) {

SunLine(-27);
SunLine(-28);
SunLine(13);
SunLine(30);
SunLine(33);
SunLine(66);


for (var d =38;d<=55;d+=2) {
  SunLine(d);
}
}
else{
  for (var d =-90;d<=90;d+=5) {
//  SunLine(d);
  }
}

// K is the constant for the spread of the sun's rays
// bascially divides the 
var K = 2.2;
var sunH = 4000/mpp;

for (var d =-90;d<=90;d+=5) {
  if (d!=0) {
    var x1 = d2x(d);
    var y1 = base_y

    var a = radians(90-Math.abs(d));
    var b = (Math.PI/2-a)/K;
    var ta = Math.tan(a);
    var tb = Math.tan(b)

    // middle control point is where the line would
    // intersect the y axis
    var x2 = mid;
    var y2 = base_y-Math.abs(d)/90*axisW/2*ta

    // end control point is where the sun is.
    var x3 = mid
    var y3 = base_y-sunH;

    // 

    var x4 = mid + sunH*tb * math.sign(d)
    var y4 = base_y;

    
//    line(x1,y1,x2,y2,"#0xFF0000")
//    line(x3,y3,x4,y4,"#0x00FF00")
    

    var intersect = math.intersect([x1,y1],[x2,y2],[x3,y3],[x4,y4]);

    console.log(intersect)


    ctx.strokeStyle="#c0c040"
    ctx.beginPath();  
    ctx.moveTo(x1,y1);
//    ctx.quadraticCurveTo(x2,y2,x3,y3)
    ctx.quadraticCurveTo(intersect[0],intersect[1],x3,y3)
    ctx.stroke();

  }  
}


  //SunLine(47.6);


  
              
            
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999px

Console