Re: Dealing with destructive openGL functions

[Sam S. <sd...@gn...>]

> * In message <3D8...@gm...>
> * On the subject of "Dealing with destructive openGL functions"
> * Sent on Thu, 19 Sep 2002 19:36:41 -0600
> * Honorable Scott Williams <or...@gm...> writes:
>
> On a different but related topic: there is a function family
> 
> gluProject(GLdouble objx, GLdouble objy, GLdouble objz, const GLdouble
> modelMatrix[16], const GLdouble projMatrix[16], const GLint viewport[4],
> GLdouble *winx, GLdouble *winy, GLdouble *winz)
> 
> which project coordinates from object space into screen space, returning
> the new coordinates destructively via the last three pointers. This
> doesn't seem like the lisp way to me... it seems it would be better to
> return a vector. How do I go about lisp-izing the array arguments?
> What's the most convenient notation? If i'm going to bother to wrap the
> function to make it return a vector, i might as well make it take
> arguments more painlessly.
> 
> What does the list think of this?

if you specify the args as :out they are returned as multiple values.
see <http://clisp.cons.org/impnotes/dffi.html#param-mode>
-- 
Sam Steingold (http://www.podval.org/~sds) running RedHat7.3 GNU/Linux
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