Re: [ooc-compiler] C interface problems

[Stewart G. <sgr...@ii...>]

Hi August,

> One potential problem: the glut functions are defined as "APIENTRY", 
> which under Windows means that they use the "stdcall" calling 
> convention rather than "cdecl". Therefore, you should probably specify 
> "Pascal" rather than "C" as your interface type. That is:
>   MODULE Glut [INTERFACE "Pascal"; LINK LIB "glut32"; LIB "opengl32"; 
> END];
> I think the same goes for the other GL modules. Presuming that the 
> linker knows the procedure attributes, that may be why it is giving 
> the error (ie. the procedure name matches, but the attributes are 
> wrong).

I ran a quick check, and it looks like this is indeed what happens. The 
following should compile and link fine. It also runs OK, opening a 
window and correctly calling the display procedure.

MODULE Test;
   IMPORT C, Glut;
   VAR w: C.int;
   PROCEDURE Display ["Pascal"];
   END Display;
BEGIN
   w := Glut.CreateWindow("OpenGL Test");
   Glut.DisplayFunc(Display);
   Glut.MainLoop
END Test.

MODULE Glut [INTERFACE "Pascal"; LINK LIB "glut32"; LIB "opengl32"; 
END];
   IMPORT C;
TYPE
   DisplayCallback = PROCEDURE;

   PROCEDURE ["glutCreateWindow"] CreateWindow*(title: ARRAY OF C.char): 
C.int;
   PROCEDURE ["glutDisplayFunc"] DisplayFunc*(p: DisplayCallback);
   PROCEDURE ["glutMainLoop"] MainLoop*;
END Glut.

Hope this helps.

Cheers,
   Stewart