polarimagecallback = function(isArctic, context)
{
    if (context) {
        if (isArctic == true) {
            if (articfirst == true) {
                // 그리기
                var centerX = context.canvas.width / 2;
                var centerY = context.canvas.height / 2;
                var radius = (context.canvas.width / 2) - 10;

                context.beginPath();
                context.arc(centerX, centerY, radius, 0, 2 * Math.PI, false);
                context.lineWidth = 5;
                context.strokeStyle = 'red';
                context.stroke();

                articfirst = false;

                return true;
            }
        }
        else {
            if (antarcticfirst == true) {
                // 그리기
                var centerX = context.canvas.width / 2;
                var centerY = context.canvas.height / 2;
                var radius = (context.canvas.width / 2) - 10;

                context.beginPath();
                context.arc(centerX, centerY, radius, 0, 2 * Math.PI, false);
                context.lineWidth = 5;
                context.strokeStyle = 'green';
                context.stroke();

                antarcticfirst = false;

                return true;
            }
        }
    }

   return false;
}

clearPolarimaga = function()
{
   var context = cmworld3Viewer.polar.getPolarimageContext(true);
   context.clearRect(0, 0, context.canvas.width, context.canvas.height);
   //var w = context.canvas.width;
   //context.canvas.width = 1;
   //context.canvas.width = w;
   
   cmworld3Viewer.polar.updatePolarImage();
}

directDraw = function ()
{
	// 극지방에 그려질 수 있는 범위를 늘려보자.
	cmworld3Viewer.polar.setPolarImageRadius(40);

	var image1 = document.createElement('img');
	
	image1.addEventListener('load', function (event)
	{
		// 극지의 이미지 context를 가져옴.
		// 파라메터가 true이면 북극의 이미지를 false면 남극의 이미지를 가져옴.
		// 그래픽 작업은 일반적인 contex를 다루는 함수와 동일함.
		var context = cmworld3Viewer.polar.getPolarimageContext(true);
		context.globalAlpha = 1.0;

		var cWidth = context.canvas.width;
		{
			context.save();
			// move to the center of the canvas
			// 중심으로 이동.
			context.translate(cWidth / 2, cWidth / 2);
			// 회전.
			context.rotate(90 * Math.PI / 180);
			
			//context.drawImage(image1, -image1.width / 2, -image1.width / 2);
			context.drawImage(image1, 0, 0, image1.width, image1.height, -(cWidth / 2), -(cWidth/2), cWidth, cWidth);
			//context.drawImage(image1, 0, 0, image1.width, image1.height, 0,0, 1024,1024);
			
			context.restore();
			
			context.fillStyle = "red";
			
			var pt = new THREE.Vector2();
			for (var i = 0.0; i < 127; i++)
			{
			    pt = cmworld3Viewer.polar.getPolarImagePosition(i, 80);
			
			   context.fillRect(pt.x -2 , pt.y - 2, 4, 4);
			}
		}
		
		context = cmworld3Viewer.polar.getPolarimageContext(false);
		context.globalAlpha = 1.0;

		var cWidth = context.canvas.width;
		{
			context.fillStyle = "green";
			
			var pt = new THREE.Vector2();
			for (var i = 0.0; i < 127; i++)
			{
				pt = cmworld3Viewer.polar.getPolarImagePosition(i, -80);
				context.fillRect(pt.x - 2, pt.y - 2, 4, 4);
			}
		}
		
		// 이미지를 갱신하였다면, cmworld3Viewer에 갱신 되었다고 알려 주어야 함
		cmworld3Viewer.polar.updatePolarImage();
	    }, false);
		
    image1.src = "이미지 경로";
}
example = function () {
	cmworld3Viewer.polar.enablePolarImageOverlay(30, 1024, polarimagecallback)
	
	var eye_x = 92.28543980222322;
	var eye_y = 79.45410790253543;
	var eye_h = 3367027.811760755;
	var look_x = 79.3173629383541;
	var look_y = 82.13269451458342;
	var look_h = 10;
	
	cmworld3Viewer.gotoLookAt(eye_x, eye_y, eye_h, look_x, look_y, look_h);
}