(define %ptr ffi:ptrdiff_t)
(define-simple-foreign-type void ffi:void)
-(define-simple-foreign-type GLboolean ffi:uint8)
(define-simple-foreign-type GLbyte ffi:int8)
(define-simple-foreign-type GLubyte ffi:uint8)
(define-simple-foreign-type GLchar ffi:int8)
(define-simple-foreign-type void-* '*)
(define-simple-foreign-type const-GLvoid-* '*)
+(define GL_FALSE 0)
+(define GL_TRUE 1)
+
+(define-foreign-type GLboolean ffi:uint8
+ (lambda (x) (if x GL_TRUE GL_FALSE))
+ (lambda (x) (eqv? x GL_TRUE)))
+
(define (coerce-array-pointer x)
(cond
((ffi:pointer? x)