tion(e) {
		if(e.buttons == 1) {
			const canvas_rect = canvas.getBoundingClientRect();
			const sx = e.clientX - canvas_rect.left;
			const sy = e.clientY - canvas_rect.top;
			const cx = 320 - (sx - mousemove_sx);
			const cy = 320 - (sy - mousemove_sy);
			const functions = s2x_x2s_s2y_y2s_from_UI();
			const s2x = functions[0];
			const s2y = functions[2];
			document.getElementById("center_x").value = s2x(cx).toFixed(5);
			document.getElementById("center_y").value = s2y(cy).toFixed(5);
			mousemove_sx