Terasology themeable UI brainstorming

gistfile1.json

{
    "id": "main-menu",
    "class": "UIWindow",
    "children": [
        {
            "id" : "main-window",
            "class" : "UIWindow",
            "image" : "engine:bg.png",
        },
        
        {
            "id" : "some-button",
            "class" : "UIButton",
            "parameters" : {
                "onclick": "methodeName",            # the function to call
                "onhover" : "otherMethod",

                "position-type" : "absolute",           //absolute to whole screen / relative to parent widget
                                                        // x3ro: Not sure if we need this. Couldn't we just
                                                        // always be relative to the parent and put absolute
                                                        // stuff in the "root"?

                "position" : ["50%", "50%"],   //pixel position by percentage of the current screen or just by pixels

                
                "vertical-align": "center",          //left / center / right - if this is used the position attribute should be added from this location
                "horizontal-align" : "center",        //top / center / bottom - same here
                
                "image" : "engine:someimage.png",     //image to load
                "image-normal" : [0, 0, 100, 30],        //x y width hight in someimage.png
                "image-hover" : [0, 30, 100, 30],
                "image-pressed" : [0, 60, 100, 30]
            }
        }
    ]
}