PFNGLVARIANTPOINTEREXTPROCDart typedef
        PFNGLVARIANTPOINTEREXTPROCDart =
     void Function(int id, int type, int stride, Pointer<NativeType>  addr)
    
    
    
Implementation
typedef PFNGLVARIANTPOINTEREXTPROCDart =
    void Function(int id, int type, int stride, Pointer<NativeType> addr);