I'd like to list the following resources which I've found very useful, most of this is from there: GDI+ Classes José Roca's GDI+ reference and forum developpez, a french site but with in-depth explanation. And a warm thanks to Sjaak Priester for his wonderful ColorMatrix tool and source which the ColorMatrix funtions are built on. I've forgot , thanks to Paul Campbell (PaulIA) for the great UDF, Malkey, UEZ, trancexx, monoceres, and everybody else for posting generous GDI+ examples. This UDF