public void invalidate(LetterQuad cursor) {
        totalWidth = -1;
        totalHeight = -1;

        while (!cursor.isTail() && !cursor.isInvalid()) {
            cursor.invalidate();
            cursor = cursor.getNext();
        }
    }
Manage and align LetterQuads
@author YongHoon
jme3-core/src/main/java/com/jme3/font/Letters.java