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var my_canvas = document.createElement('canvas');
			my_canvas.width = 500;
			my_canvas.height = 300;
			document.body.appendChild(my_canvas);
			var ctx = my_canvas.getContext('2d');
			var x = 20; 
			var y = 20;
			var fps = 60;
			
			animacja();
			
			function animacja(){
				requestAnimationFrame( animacja )
        ctx.fillStyle = 'rgba(255,255,255,0.2)';
				ctx.fillRect(0,0,my_canvas.width, my_canvas.height);
        ctx.fill();
        
				x = x+2;
				y = y+1.4;
				ctx.fillStyle= '#38ccdd';
        ctx.beginPath()
				ctx.arc(x+30, y+30,30,0,Math.PI*2,);
        ctx.fill();
			}

<script>
</script>