var clickDownTime = 0;
 
(function () {
    var n = 1;
  
    this.clickDownOnEntity = function (entityID, mouseEvent) {
        var d = new Date();
        clickDownTime = d.getTime();
    };
    this.clickReleaseOnEntity = function (entityID, mouseEvent) {
        var d = new Date();
        var elapsedMsecs = d.getTime() - clickDownTime;
        if (elapsedMsecs > 500) {
            n = n - 1; 
        } else {
            n = n + 1;
        }
        if ((n > 12) || (n < 1)) {
            n = 1;
        }
        print("n=" + n);
        Entities.editEntity(entityID, {
            textures: "{ \"jupitermap": \"http://localhost:8888/planets/planets/textures/" + n + ".jpg\" }"
        });
 
    };
 
})