On Tuesday 19 June 2007 23:10, Guillaume Laurent wrote: > On Tuesday 19 June 2007, Alexandre Prokoudine wrote: > > Second question is about KDE4. Are you planning to port RG when KDE 4 > > is out or when it goes beta?
Or neither? > I assume you mean 'leaves beta' by 'is out', so I would say beta (even > though I've repeatedly said it wouldn't be worth bothering with this until > KDE4 has reached mainstream status) I presume it will be possible to run KDE4 applications under a KDE3 desktop, provided the right libraries and things are in place somewhere? I suppose it must be; otherwise it wouldn't be possible to run them under a non-KDE desktop. > - some of the most significant overhauls we intend to do (essentially, > getting rid of the QCanvas) would be rendered obsolete by Qt4. And > actually, given the improvements of QGraphicsView over QCanvas, turning the > notation and matrix view into plain widgets could very well be a waste of > time after all. I'm not sure that QGraphicsView will help much, in the case of notation. Most of the time, we do actually want to have pixel coordinates be exact integers, and we already do our own scaling for "font elements". I don't think moving from QCanvas to QGraphicsView would hurt anything much, but I think to do it in a proper way (using font elements and canvas scaling) would probably be more work than moving to a plain old widget, and with no particular gain. To further explain: although we use QCanvas now, we don't let it do any of its own scaling or the like. That's partly because it doesn't handle non-integer coordinates, and partly because Qt3's unicode support doesn't cover the >16-bit plane containing musical notation elements, thus making it very painful to support musical notation fonts via Qt3 font rendering. Both of these we work around by doing our own scaling and rendering. The first of them is certainly fixed by QGraphicsView; I _think_ Qt4 also now supports surrogate pairs in QChar, which would possibly mean the second is fixed too. But the point is that now that we've worked around them, it may be more work to un-work-around them than it would be to simply ignore QGraphicsView and continue to do our own thing with a widget -- which would probably still be faster, and would still permit us to use the nice new Qt4 paint support for things like transparency if desired. I may have some opportunity to test this, as it's possible I might soon have a chance to refactor RG's notation code for Qt4, for another (paid) project. I hope so, because it would be an excellent opportunity to feed the results back into a future Qt4 Rosegarden, as well as think again about all the things I'm always meaning to think again about, like voice support. Just saying that again has probably jinxed it of course. Chris ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Rosegarden-devel mailing list [email protected] - use the link below to unsubscribe https://lists.sourceforge.net/lists/listinfo/rosegarden-devel
