Cast function pointers for gluTessCallback

The glu type does not work on Mac OSX, and an un-casted version does not
work in Debian.. Hopefully casting it to GCallback (void-void function)
will work both places..

diff --git a/src/objects/grits-poly.c b/src/objects/grits-poly.c
index c2c9923ac5f2a6359d805af4d956d2cb9ef6aa91..357afaefb84cc426b19bb40e1667ddb3989f0e82 100644 (file)
--- a/src/objects/grits-poly.c
+++ b/src/objects/grits-poly.c
@@ -31,9 +31,9 @@ static void grits_poly_tess(gdouble (**points)[3])
 {
        //g_debug("GritsPoly: tess");
        GLUtesselator *tess = gluNewTess();
-       gluTessCallback(tess, GLU_TESS_BEGIN,  glBegin);
-       gluTessCallback(tess, GLU_TESS_VERTEX, glVertex3dv);
-       gluTessCallback(tess, GLU_TESS_END,    glEnd);
+       gluTessCallback(tess, GLU_TESS_BEGIN,  G_CALLBACK(glBegin));
+       gluTessCallback(tess, GLU_TESS_VERTEX, G_CALLBACK(glVertex3dv));
+       gluTessCallback(tess, GLU_TESS_END,    G_CALLBACK(glEnd));
        for (int pi = 0; points[pi]; pi++) {
                gluTessBeginPolygon(tess, NULL);
                gluTessBeginContour(tess);