On Tuesday, 5 January 2016 at 16:25:01 UTC, TheDGuy wrote: > But how do i know which line or column my pixel is in? - study D operator overloading, I've given you the solution. > And what is 't' in 'opIndexAssign'? - t is what you want to assign. It can be an uint or maybe a float[4]. Look at my bitmap class.