def set_projection3D(self):
        """Sets a 3D projection mantaining the aspect ratio of the original window size"""
        # virtual (desired) view size
        vw, vh = self.get_window_size()

        gl.glViewport(self._offset_x, self._offset_y, self._usable_width, self._usable_height)
        gl.glMatrixMode(gl.GL_PROJECTION)
        gl.glLoadIdentity()
        gl.gluPerspective(60, float(self._usable_height) / self._usable_width, 0.1, 3000.0)
        gl.glMatrixMode(gl.GL_MODELVIEW)

        gl.glLoadIdentity()
        gl.gluLookAt(vw / 2.0, vh / 2.0, vh / 1.1566,   # eye
                  vw / 2.0, vh / 2.0, 0,             # center
                  0.0, 1.0, 0.0                      # up vector
                  )
dataset/ETHPy150Open los-cocos/cocos/cocos/director.py/Director.set_projection3D/swapped operands of `/`