+ void getWindow (double& xmin, double& ymin, double& xmax, double& ymax);
+ void getViewport (double& xmin, double& ymin, double& xmax, double& ymax);
+ void getTextExtent (const char *szText, double* x, double* y);
+ double getCharHeight ();
+ double getCharWidth ();
+ SGPDriver& getDriver() {return m_driver;}
+ const SGPDriver& getDriver() const {return m_driver;}
+