private void init() {
		final Pattern p = Pattern.compile("(?i)<polygon\\s+[^>]*points=\"([^\"]+)\"");
		final Matcher m = p.matcher(svg);
		double minX = Double.MAX_VALUE;
		double minY = Double.MAX_VALUE;
		double maxX = -Double.MAX_VALUE;
		double maxY = -Double.MAX_VALUE;
		if (m.find() == false) {
			return;
		}
		final String points = m.group(1);
		final StringTokenizer st = new StringTokenizer(points, " ");
		while (st.hasMoreTokens()) {
			final String token = st.nextToken();
			final StringTokenizer st2 = new StringTokenizer(token, ",");
			final double x = Double.parseDouble(st2.nextToken().trim());
			final double y = Double.parseDouble(st2.nextToken().trim());
			if (x < minX) {
				minX = x;
			}
			if (y < minY) {
				minY = y;
			}
			if (x > maxX) {
				maxX = x;
			}
			if (y > maxY) {
				maxY = y;
			}
		}

		this.width = maxX - minX;
		this.height = maxY - minY;
	}