 {return 0;}
			document.getElementById("error").innerHTML = "<b>Error:</b> " + error.message;
		}
	}
	document.getElementById("center_y").value = y.toFixed(5);
	draw_canvas();
}

function reset_focus() {
	document.getElementById("center_x").value = 0;
	document.getElementById("center_y").value = 0;
	draw_canvas();
}

function divide_scale() {
	document.getElementById("scale").value = Number(document.getElementById("scale").value / 2);
	draw_canvas();
}

function multiply_scale() {
	document.getElementById(