/* -------------------- GUI update ------------------------- */
void guiUpdate() // update the ui
{
energyGUI.text = "ENERGY: " + playerEnergy.getEnergyPercent().ToString("F0") + "%";
scoreGUI.text = "SCORE: " + playerScore.getScore().ToString();
lvlGUI.text = "LEVEL: " + playerLevel.getLevel().ToString();
}