On 26 Feb 2012, at 16:30, Georg Potthast wrote: > I tried the example on Windows, Linux and DOS now - it did work.
I'm sure it does - I'd hazard that it probably appears to work fine on 80%-90% of current systems, then will occasionally fail oddly on most of the others, and outright now work at all on the remainder. In particular it can be very sensitive to how the graphics driver updates the display, so we often see different behaviour on different graphics cards, on otherwise similar host machines. And I'm speaking from hard-earned experience here... What might be interesting to try is to run your example, minimise the window then re-show it. My experience is that this will generally (but not always) draw an empty window without any of the previously drawn features retained. Basically, incremental drawing, using fltk, can't reliably be done the way you have shown. If you really want to do incremental drawing, as in the example, then you probably need to look at using an fl_offscreen buffer, since that will work reliably across all the systems I've ever used. I've posted a few examples of that to this list in the past, so there's some stuff out there for you to check out (or I can post again if that would help.) FWIW, I suspect that a lot of folk see fl_offscreen as being "advanced" but I use it a fair bit and think it is straightforward enough, and useful enough, to be considered in an introductory text such as you are proposing! > On Linux the header file had to be changed to lower case fl_draw: #include > <FL/fl_draw.H> Yup. Linux is correct. For portability, these are case-sensitive, but WinXX/DOS and OSX tend to be more "case remembering" rather than "case sensitive." > I am open to correct any issues. I would prefer these messages to be sent to > me directly via email. Ah, OK, but I have to post to the list too, as I prefer these things to be discussed in the open, in the hope that the discussion might help others at some point. _______________________________________________ fltk mailing list [email protected] http://lists.easysw.com/mailman/listinfo/fltk
