PFNGLCOPYTEXSUBIMAGE1DEXTPROCDart typedef
        PFNGLCOPYTEXSUBIMAGE1DEXTPROCDart =
     void Function(int target, int level, int xoffset, int x, int y, int width)
    
    
    
Implementation
typedef PFNGLCOPYTEXSUBIMAGE1DEXTPROCDart =
    void Function(int target, int level, int xoffset, int x, int y, int width);