On Mon, Mar 21, 2011 at 08:41, Mattias Gaertner <[email protected]> wrote: > On Mon, 21 Mar 2011 04:58:18 +1000 > Alexander Klenin <[email protected]> wrote: >> Hm. For me GUI means "graphical user interface" -- that is, windows (aka >> forms), >> interacting with mouse, etc. >> I have just committed a demo which does not have any of this, >> and yet successfully draws TChart to a file -- see previous mail. >> Maybe for you GUI means a different thing? > > Yes. The GUI of the screen. > By accessing the LCL canvas you access the widgetset (gtk2) which > accesses the current screen. For example the gtk2 asks for > theme, fonts, screen color depths and sub pixel rendering parameters. > A cgi program has no screen.
It is ok to ask for all these things since thay are necessary to render the chart. However, the fact they are unconditionally taken from the screen is IMO a deficiency of either GTK or LCL-GTK. As you can see in this thread, as soon as this deficiency is worked around, (in this case, by using Xvfb utility), the problem is solved. > There are other implementations of TFPCustomCanvas without the need > of a screen. The fcl provides one. Probably TAggFPCanvas can work > without screen too. The last time I checked the main problem is the > font support. It is far less comfortable as the LCL. Also, AggPas supports neither Pen.Style not Brush.Style. > It is a good idea to add a render function to TAChart for > TFPCustomCanvas. Generally, yes. But as I stated in the previous mail, simply adding a function may not help. Still, I am working on this ;) -- Alexander S. Klenin -- _______________________________________________ Lazarus mailing list [email protected] http://lists.lazarus.freepascal.org/mailman/listinfo/lazarus
