Re: FLI type error
"David McClain (as dbm at refined-audiometrics dot com)" <[email protected]>
| Newsgroups | gmane.lisp.lispworks.general |
|---|---|
| Message-ID | <[email protected]> |
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