Re: FLI type error
"Paul Werkowski (as pw at snoopy dot qozzy dot com)" <[email protected]>
| Newsgroups | gmane.lisp.lispworks.general |
|---|---|
| Message-ID | <[email protected]> |
Well, GLCHAR is lisp :char. I see that the FLI manual has things like convert-to-foreign-type etc. I shall poke around in there for awhile. Thanks for the suggestion, PW On 3/7/2026 12:43 PM, David McClain wrote: > No… I now see. > > It appears that Lisp cannot automatically convert your Lisp string to the required C type (:POINTER OPENGL:GLCHAR). There has always been a sometimes conversion ability to allow Lisp strings to become C strings. But your required type is not a “C String” kind of pointer. > > Yes, even though it probably really is a C string type, I have no idea whether OPENGL:GLCHAR is a 8-bit ASCII char, or a Unicode wide char, etc. So probably no implicit LW conversions would apply. > > IOW… you probably now have to provide your own explicit conversions. > > - DM > >> On Mar 7, 2026, at 10:37, David McClain <[email protected]> wrote: >> >>> Both of these get a runtime error >>> "aPos" (and "triangleColor") cannot be converted to foreign type >>> (:POINTER OPENGL:GLCHAR). >>> >> Offhand… did the OpenGL API change since 10 years ago? Perhaps now expects an array of char, or a string pointer? >> >> >> >>> On Mar 7, 2026, at 09:59, Paul Werkowski (as pw at snoopy dot qozzy dot com) <[email protected]> wrote: >>> >>> I'm looking at some code from 5-10 years ago, experimenting with OPENGL, that uses the LW example code to setup the interface. The icosahedron example works fine so no issue there. >>> >>> Here are two fragments from my code. >>> >>> (let ((pos-attr (gl-get-attrib-location shader-pgm "aPos")) >>> >>> (let((unicolor (gl-get-uniform-location >>> shader-pgm "triangleColor"))) >>> >>> Both of these get a runtime error >>> "aPos" (and "triangleColor") cannot be converted to foreign type >>> (:POINTER OPENGL:GLCHAR). >>> >>> GLCHAR is defined in opengl/types.lisp as >>> >>> (fli:define-c-typedef (glchar (:foreign-name "GLchar")) >>> :char) >>> >>> Same issue with both LWW 8.1.2 64 bit and 7.1.2 32 bit. >>> >>> This all used to work. What could be wrong??? >>> >>> Puzzled again, >>> Paul >>> >>> >>> >>> _______________________________________________ >>> Lisp Hug - the mailing list for LispWorks users >>> [email protected] >>> http://www.lispworks.com/support/lisp-hug.html _______________________________________________ Lisp Hug - the mailing list for LispWorks users [email protected] http://www.lispworks.com/support/lisp-hug.html