public void addAttribute(String attribute, String value) {
		if (value == null) {
			value = "";
		}
		
		if (attribute.equals(FILL) ) {
			value = morphColor(value);
		}
		if (attribute.equals(STROKE_OPACITY)) {
			if (value.equals("0")) {
				props.setProperty(STROKE, "none");
			}
		}
		if (attribute.equals(STROKE_WIDTH)) {
			if (value.equals("")) {
				value = "1";
			}
			if (value.endsWith("px")) {
				value = value.substring(0,value.length()-2);
			}
		}
		if (attribute.equals(STROKE)) {
			if ("none".equals(props.getProperty(STROKE))) {
				return;
			}
			value = morphColor(value);
		}
		
		props.setProperty(attribute, value);
	}