Create OpenGL window on X11

**Ñuño Martínez** · 13-05-2009, 10:28 AM

System: GNU/Linux (Ubuntu)
Compiler/IDE: Free Pascal
Libraries/API: OpenGL

I'm trying to add OpenGL support to my Allegro.pas project. To do that I must create an OpenGL window and tell to Allegro the handler/function of that window.

I can do it on MS-Windows but I have no idea about how to do it on X systems because I have almost no experience on X. I've looked on the Internet and everything I found is GLUT, GLX and SDL related, but I can't use that because Allegro must access to the window to intercept messages (keyboard, etc.). As I've seen in Allegro's sources it uses the lowest X11 level.

I've read some C code about how to add OpenGL support to the original Allegro but I see it too much complex to translate it directly to Pascal.

Can somebody help me?

**AthenaOfDelphi** · 13-05-2009, 10:41 AM

Send me the source code and I'll look at it... see if I can translate it.

**Ñuño Martínez** · 13-05-2009, 11:12 AM

Thanks really. I'll send it to you as soon as I can.

**noeska** · 13-05-2009, 04:17 PM

maybe this is of use also http://www.delphigl.com/do_download.php?f=9000

its a basic opengl with x example.

**AthenaOfDelphi** · 14-05-2009, 09:47 AM

?ëu?±o,

I've not received the mail... I've been checking my spam filter and it's not been dumped in there. Can you send it to 'athena at outer hyphen reaches dot com'.

Thanks

**Ñuño Martínez** · 14-05-2009, 01:09 PM

Thanks both.

@Athena: I did send it to your MSN account.

By the way, I've asked on other forums and mailing lists and it seems there's a problem with GLX. I mean Free Pascal doesn't links it and I don't know why. I did add "-klglx" to the compilation command but it says "/usr/bin/ld: lglx: No such file: No such file or directory". May be if I fix this then I can do the other.

Which package is the GLX dev one? I can't find it on Synaptic.

**JSoftware** · 14-05-2009, 01:54 PM

Try -k-lglx

**Ñuño Martínez** · 14-05-2009, 02:44 PM

Originally Posted by JSoftware

Try -k-lglx

It results in "/usr/bin/ld: cannot find -lglx"

**AthenaOfDelphi** · 14-05-2009, 07:43 PM

I could take a stab at a straight translation to Pascal, as I'm sure you can, but it depends on a whole bunch of stuff which is clearly defined in other headers/includes... without them, it really would be a stab in the dark.

From what you've said in your mail, you may well be able to get better assistance from others.

Was there a particular part of that function that was causing you problems or was it the whole thing?

**Ñuño Martínez** · 17-05-2009, 11:27 PM

Originally Posted by AthenaOfDelphi

Was there a particular part of that function that was causing you problems or was it the whole thing?

I have this run-time error:

Code:

./exbasic: symbol lookup error: /usr/local/lib/libagl.so: undefined symbol: glXQueryExtension

"libagl.so" is an add-on for the original Allegro that adds OpenGL support.

I did ask both Allegro developers and FPC developers and no one gives me an answer. They said it should work if I add "-l-kglx" option or similar but then I get a compilation-time error.

If I can fix this then I can finish it by myself.