Re: [lazarus] Moving a graphics app from Win to Linux

[Mat Ballard]

g'day Mattias, re: I have written a graphics app (in D3 for display/render design) that heavily depends on large bitmaps. ... Anybody doing graphics out there? i have a very serious graphs app, or set of apps, and am watching progress of Lazarus very closely. in the long run, i will need to go to 64 bit. however, for speed reasons, it makes major use of TBitmap.Scanline - so i face a very major porting problem unless and until this is implemented. Well, we can implement TBitmap.ScanLine by automatically creating a TLazIntfImage. Of course this needs some bookkeeping to reduce the update between the TLazIntfImage and the Handle. Delphi code accessing this ScanLine will probably work with only a few changes under windows and maybe a few Linux Desktops. Would that be sufficient for you? that would be pretty damn good, except for below ... Of course to get the grade 'runs on Lazarus' you have to enhance the Delphi code for the full TRawImage properties and in the end you will probably using TLazIntfImage.Pixels. And of course your code can not be used easily by fpImage in server applications. server applications is the eventual goal: the general design is a library of very specialized graphics function, which have several different front-ends for different purposes - one of which is a web service (others are GUI, one is command line). i take it that TLazIntfImage has the same X-dependence issues on Linux as did TBitmap did under Kylix ? the principal issue for me is that we would eventually like to handle extremely large bitmaps - eg: A3 size at 2400 dpi. this neccessitates a 64-bit migration path. Linux is preferred, but not mandatory, as a server OS. my own thinking was to carefully watch the evolution of Lazarus, and to see whether it would be better to: Hack TLazIntfImage to create a Scanline property for the chosen OS - lots of {$IFDEF }ing; Rewrite the graphics library to use TLazIntfImage; Rewrite the graphics library to use the GD Library; Port Theo Lustenberger's TXLBitmap (http://www.theo.ch/kylix/webcgi.png) then rewrite the graphics library to use it. it can be downloaded from http://www.theo.ch/kylix/XLship.zip. the discussion for this can be found at: http://tinyurl.com/9jw4a naturally, many issues come into the decision. for example, if Borland pulled their finger out and made Delphi64, it would be a no-brainer. cheers, Mat ________________________________________ rm -rf /mnt/windows/* ________________________________________ Dr Mat Ballard, CSIRO Molecular Science, Bag 10, Clayton South MDC, Vic 3169. AUSTRALIA. tel: 61-3-9545-2425 fax: 61-3-9545 2446 [EMAIL PROTECTED] http://www.wark.csiro.au/ballard/ Linux Registered User #6854 _________________________________________________________________ To unsubscribe: mail [EMAIL PROTECTED] with "unsubscribe" as the Subject archives at http://www.lazarus.freepascal.org/mailarchives