private void moveScreen() {
        if (Math.abs(mouseX - 0) < Properties.properties.MOVE_SCREEN_AREA) {
            frame.startX -= 10;
        }
        if (Math.abs(mouseX - frame.width) < Properties.properties.MOVE_SCREEN_AREA) {
            frame.startX += 10;
        }
        if (Math.abs(mouseY - 0) < Properties.properties.MOVE_SCREEN_AREA) {
            frame.startY -= 10;
        }
        if (frame.height - 100 - mouseY < Properties.properties.MOVE_SCREEN_AREA) {
            frame.startY += 10;
        }
        if (frame.startX < 0) frame.startX = 0;
        if (frame.startX > Properties.properties.UNIVERSE_SIZE_X - frame.width)
            frame.startX = Properties.properties.UNIVERSE_SIZE_X - frame.width;
        if (frame.startY < 0) frame.startY = 0;
        if (frame.startY > Properties.properties.UNIVERSE_SIZE_Y - frame.height)
            frame.startY = Properties.properties.UNIVERSE_SIZE_Y - frame.height;
    }