1. June 26,2002fine@bnl.gov ACAT2002, Moscow Cross-Platform Qt-Based Implementation of Low Level GUI Layer of ROOT V.Fine BNL, Upton

2. June 26,2002fine@bnl.gov ACAT2002, Moscow Why ROOT is multi-platform ? Just to be healthy ! Just because there are plenty of Windows users around

3. June 26,2002fine@bnl.gov ACAT2002, Moscow ROOT for different platforms http://root.cern.ch/root/images/ftpstats.gif http://root.cern.ch/root/images/ftpstats.gif

4. June 26,2002fine@bnl.gov ACAT2002, Moscow ROOT low level GUI interface TVirtualX TGX11TGWIN32TGWin32GDK ROOT (TG ROOT (TVirtualPad) 3 different implementations to develop and support

5. June 26,2002fine@bnl.gov ACAT2002, Moscow ROOT Qt-based GUI interface TVirtualX TQt ROOT only one (!) implementation

6. June 26,2002fine@bnl.gov ACAT2002, Moscow What is Qt

7. June 26,2002fine@bnl.gov ACAT2002, Moscow Why Qt ? It does what it promises ! Myself have been confused no time with Qt documentation and functionality But it is not my (ROOT user) business to make the ROOT team life more easy. The plain implementation of TVirtualX that doesn’t bring any new feature can not justify the efforts to introduce a new extra layer and external dependency of the ROOT package

8. June 26,2002fine@bnl.gov ACAT2002, Moscow (ROOT + Qt) based applications The question is: “How easy can one create a complex application that uses ROOT to do what only ROOT can provide (namely the features coming from the built-in C++ interpreter) and use Qt to create cross-platform GUI ? ”

9. June 26,2002fine@bnl.gov ACAT2002, Moscow libQtgui library Qt-based ROOT consists of a standard ROOT installation with the addition of two additional shared libraries The libQtGui library contains implementations of abstract interfaces provided by the TGuiFactory ROOT class: TCanvasImp TBrowserImp TContextMenuImp TControlBarImp TInspectorImp 1 day to implement ! 2 days to implement 0.5 day to implement

10. June 26,2002fine@bnl.gov ACAT2002, Moscow Qt designer to create ROOT embedded canvases

11. June 26,2002fine@bnl.gov ACAT2002, Moscow A test application to combine ROOT and Qt Widget

12. June 26,2002fine@bnl.gov ACAT2002, Moscow Where to get Qt-ROOT from

13. June 26,2002fine@bnl.gov ACAT2002, Moscow Qt-ROOT FAQ

14. June 26,2002fine@bnl.gov ACAT2002, Moscow Qt-ROOT CVS The source code is available via CVS repository as well. To check out the sources, you need to be running CVS 1.10 or later (check by doing cvs -v), and have your $CVSROOT set to :pserver:cvs@usatlas.org:/rootbnl/cvs The password for user cvs is cvs. Two cvs commands will do the job: cvs -d :pserver:cvs@usatlas.org:/rootbnl/cvs login cvs -d :pserver:cvs@usatlas.org:/rootbnl/cvs co root AFS access will be provided also.

15. June 26,2002fine@bnl.gov ACAT2002, Moscow Conclusion There are enough evidences the present approach allows the ROOT developers as well as ROOT users to work with code that has no X11/WIN32 graphics subsystem dependencies and at the same time opens unrestricted access to a rich set of ready-to- use commercial and free GUI Qt-based widgets. The Qt-based version was tested on Unix and Windows.

16. June 26,2002fine@bnl.gov ACAT2002, Moscow Thank you Special thanks: 1.Torre Wenaus, Yuri Fisyak, Victor Perevoztchikov 2.Anton Fokin 3.Christian Holm ChristensenChristian Holm Christensen 4.ROOT team 5.ROOT folks from ROOTTALK

17. June 26,2002fine@bnl.gov ACAT2002, Moscow 0. Long lasting application No penalty 1. Very wide used on Linux system (KDE) 2. Shipped with the source code and installation script (no technical to take over but legal issue). 1. What is accepted level: 1. one pixel was that reliable level 2. dialog window is a mandatory attibute of any system ROOT is designed like we 20 years ago 2. Qt - quality library of Widget weel-though separation of the automaically generated GUI and user-provided custom actions. (Tha tallow to share GUI across applications) 3. Functionality: They treat MS a GUI standard 3. What ROOT may end up with. The best scenario we will ned up with somethin Qt alike but in many years. 4. Price: 1. Free for non-commercial applcation on X11 platform 2. True cross platform (code designed and debugged on with free UNIX will work in Windows 3. This allow to minimiz the number of Windows license 4. Windows license is really cheap anyway (acad. price $700/developer) our experiecne did prove this worth to buy. It is much faster and better to create GUI with Qt rather struggle with TG 4.1. Lack of documentation 4.2. Lack of functionality 5 License. Qt 2. restrictive Qt 3. can be accepted