public WordPlate(ushort plateId, int w, int h)
 {
     _plateId     = plateId;
     _plateWidth  = w;
     _plateHeight = h;
     _backBuffer  = new Drawing.GLES2.MyGLBackbuffer(w, h);
 }
        const int INTERWORD_SPACE = 1; //px

        public void Dispose()
        {
            //clear all
            if (_backBuffer != null)
            {
                _backBuffer.Dispose();
                _backBuffer = null;
            }
            foreach (GLRenderVxFormattedString k in _wordStrips.Keys)
            {
                //essential!
                k.ClearOwnerPlate();
            }
            _wordStrips.Clear();
        }