projects / wxWidgets.git / blame
| Commit | Line | Data |
|---|---|---|
| 06ad8636 JS |
1 | GLCanvas class for wxWindows 1.66 using the GLX protocol extension |
| 2 | ================================================================== | |
| 3 | ||
| 4 | I have just uploaded a file 'wx166glx.tar.gz' to the wxWindows | |
| 5 | incoming directory. It contains an implementation of a GLCanvas class | |
| 6 | (interfacing an ordinary wxCanvas with OpenGL calls) for X11 (I tested | |
| 7 | with Motif, maybe it works with XView as well). I tried to imitate | |
| 8 | what Julian did in 'wxmesa1.zip' for MS Windows in conjunction with | |
| 9 | the Mesa library. | |
| 10 | ||
| 11 | Of the several possibilities to use OpenGL under X11, I chose the GLX | |
| 12 | server extension, because it is the most efficient method on machines | |
| 13 | with graphics hardware support (I expect wxWindows/OpenGL applications | |
| 14 | to _fly_ on my Indy :-). However, you don't need a 'real' OpenGL | |
| 15 | implementation to use GLCanvas -- the free Mesa library has a | |
| 16 | simulated GLX interface built-in. Just link in libMesaGLU and | |
| 17 | libMesaGL along with libwx_motif and everything should work fine. | |
| 18 | ||
| 19 | Installation: | |
| 20 | ||
| 21 | Untar wx166glx.tar.gz from your main wxWindows directory (i.e. where | |
| 22 | the `include' and `src' subdirectories are). Then apply the small | |
| 23 | patch file which has appeared in the `glx' subdirectory: | |
| 24 | ||
| 25 | % patch -p0 < glx/wx166-glx.diff | |
| 26 | ||
| 27 | Recompile the wx_motif library in the standard way. The inclusion of | |
| 28 | the GLCanvas class in libwx_motif is protected with a new 'USE_GLX' | |
| 29 | flag in wx_setup.h, so it could maybe be included in a future | |
| 30 | wxWindows release (with USE_GLX turned off by default). | |
| 31 | ||
| 32 | Two new samples (bounce and prim) are included. I adapted them from | |
| 33 | wxmesa1.zip -- they should compile under both MS Windows (with wxMesa) | |
| 34 | and X11. The makefile.unx's are set up for the Mesa libraries; if you | |
| 35 | have original libGLU/libGL's just change the GLLIBS = ... line. | |
| 36 | ||
| 37 | Problems: | |
| 38 | ||
| 39 | One more or less serious problem remains: the visual generated by the | |
| 40 | GLCanvas class must match the visual of wxCanvas.xwindow (which | |
| 41 | currently is always the screen's default visual). The end result is | |
| 42 | that you will get a nice RGB mode for OpenGL only if your display's | |
| 43 | default visual is TrueColor or DirectColor (the XFree86 S3 servers for | |
| 44 | PCs with the '-bpp 16/32' option are examples). I'm contemplating a | |
| 45 | solution where the wxCanvas drawingarea widget is destroyed and then | |
| 46 | re-created from within the GLCanvas constructor. I would welcome | |
| 47 | suggestions on this and discussions of the GLCanvas 'API'. | |
| 48 | ||
| 49 | Regards, | |
| 50 | ||
| 51 | Wolfram Gloger. | |
| 52 | (Gloger@lrz.uni-muenchen.de) |