Function GLKMathUnproject 

pub unsafe extern "C-unwind" fn GLKMathUnproject(
    window: GLKVector3,
    model: GLKMatrix4,
    projection: GLKMatrix4,
    viewport: NonNull<c_int>,
    success: *mut bool,
) -> GLKVector3

👎Deprecated: The OpenGL API is deprecated by Apple

Available on crate features GLKMathTypes and GLKMathUtils only.

Safety

• viewport must be a valid pointer.
• success must be a valid pointer or null.