+ NSSize ssize = [[[UIScreen mainScreen] currentMode] size];
+ NSSize bsize = [self bounds].size;
+
+ // Ratio of screen size in pixels to view size in points.
+ GLfloat s = ((ssize.width > ssize.height ? ssize.width : ssize.height) /
+ (bsize.width > bsize.height ? bsize.width : bsize.height));
+ return s;