Made wxGTK dataobj.cpp compile; removed flashing from wxGLCanvas samples;

some doc bug fixes


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@1465 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

utils/glcanvas/motif/readme.txt

@@ -0,0 +1,52 @@
+GLCanvas class for wxWindows 1.66 using the GLX protocol extension
+==================================================================
+
+I have just uploaded a file 'wx166glx.tar.gz' to the wxWindows
+incoming directory.  It contains an implementation of a GLCanvas class
+(interfacing an ordinary wxCanvas with OpenGL calls) for X11 (I tested
+with Motif, maybe it works with XView as well).  I tried to imitate
+what Julian did in 'wxmesa1.zip' for MS Windows in conjunction with
+the Mesa library.
+
+Of the several possibilities to use OpenGL under X11, I chose the GLX
+server extension, because it is the most efficient method on machines
+with graphics hardware support (I expect wxWindows/OpenGL applications
+to _fly_ on my Indy :-).  However, you don't need a 'real' OpenGL
+implementation to use GLCanvas -- the free Mesa library has a
+simulated GLX interface built-in.  Just link in libMesaGLU and
+libMesaGL along with libwx_motif and everything should work fine.
+
+Installation:
+
+Untar wx166glx.tar.gz from your main wxWindows directory (i.e. where
+the `include' and `src' subdirectories are).  Then apply the small
+patch file which has appeared in the `glx' subdirectory:
+
+% patch -p0 < glx/wx166-glx.diff
+
+Recompile the wx_motif library in the standard way.  The inclusion of
+the GLCanvas class in libwx_motif is protected with a new 'USE_GLX'
+flag in wx_setup.h, so it could maybe be included in a future
+wxWindows release (with USE_GLX turned off by default).
+
+Two new samples (bounce and prim) are included.  I adapted them from
+wxmesa1.zip -- they should compile under both MS Windows (with wxMesa)
+and X11.  The makefile.unx's are set up for the Mesa libraries; if you
+have original libGLU/libGL's just change the GLLIBS = ... line.
+
+Problems:
+
+One more or less serious problem remains: the visual generated by the
+GLCanvas class must match the visual of wxCanvas.xwindow (which
+currently is always the screen's default visual).  The end result is
+that you will get a nice RGB mode for OpenGL only if your display's
+default visual is TrueColor or DirectColor (the XFree86 S3 servers for
+PCs with the '-bpp 16/32' option are examples).  I'm contemplating a
+solution where the wxCanvas drawingarea widget is destroyed and then
+re-created from within the GLCanvas constructor.  I would welcome
+suggestions on this and discussions of the GLCanvas 'API'.
+
+Regards,
+
+Wolfram Gloger.
+(Gloger@lrz.uni-muenchen.de)