Graphicsview and scenegraph behave differently in a couple of areas. Scenegraph hasn't been written with millions of items in mind, and does for example not clip away items by default (as the GPU is often better in doing this).
But I'd expect 10000 items to still work pretty well on a desktop. Cheers, Lars On 10/12/11 9:44 PM, "ext qtnext" <[email protected]> wrote: >so I can add for example 10 000 Items and Scenegraph will do all >necessary cliping (for example graphicsView Chip demo will works ? just >simply porting to qml/SceneGraph ?) > > >Le 12/10/2011 21:38, Ville M. Vainio a écrit : >> If graphics view delivered acceptable performance, QML will as too - >> especially with Qt5, through the virtue of Scene Graph. If your >> scenario would more naturally be done with QPainter, you can use >> QSGPantedItem. >> >> On Wed, Oct 12, 2011 at 9:43 PM, qtnext<[email protected]> wrote: >>> Yes but How to port the timeline (imagine porting blender3d to QML ?) : >>> I was using QGraphicsView : If I have a lot of elements will it be >>>smooth ? >>> >>> >>> Le 09/10/2011 17:24, Ville M. Vainio a écrit : >>>> - I'm sure there will be a standard tree widget component, it's >>>> mandatory for any serious toolkit >>>> >>>> - You will still be able to do custom drawing with QPainter, >>>> http://doc.qt.nokia.com/qt5-snapshot/qsgpainteditem.html >>>> >>>> - I wouldn't use QAbstractItemModel for small-to-medium size models. >>>> QML does not mandate (or even encourage) using it by any means. >>>> >>>> On Sun, Oct 9, 2011 at 5:28 PM, qtnext<[email protected]> wrote: >>>>> Hi, >>>>> >>>>> I am planning to develop a non linear video system editor (After >>>>>Effect, >>>>> Final Cut Like)... The main Widget of this kind of software is the >>>>> Timeline (composed of layers, in which you can add key frame, and on >>>>>the >>>>> left panel you can directly set value of the keyframes). you can see >>>>> the curve between keyframe, hide layers, ... zoom, unzoom, scroll.. >>>>> >>>>> >>>>> - I have develop similar software years ago : first Qt2 or 3 (don't >>>>> remenber) : using Qpainter and adding removing visible items in the >>>>> timeline on the fly... >>>>> >>>>> - Then I have do that for another software with QGraphicsView : Easy >>>>>! >>>>> you add all the items in qgraphicsScene And Qt do all the job to >>>>>manage >>>>> the large number of items... I have a QtreeWidget to change property >>>>>of >>>>> each keyframe on the left... It was working fine ! But when you >>>>>wants to >>>>> customize some parts in the QtreeWidget it was not very easy ... >>>>> >>>>> - Now I plan to use Qt Quick /Qt5 (I know it's not ready to use now >>>>>... >>>>> but it's a project for next year !) : >>>>> I plan to replace all the widgets (QTreeWidget/QgraphicsWidget) by a >>>>>Qml >>>>> and QAbstractModel : it will be more flexible to use javascript, >>>>>easier >>>>> to break rectangular area, effects, .... But How can I do that in >>>>>QML >>>>> efficiently ? I will have a large numbers of items ... In short how >>>>>to >>>>> code what can be easily and efficiently done with QGraphicsView ? >>>>> >>>>> _______________________________________________ >>>>> Qt5-feedback mailing list >>>>> [email protected] >>>>> http://lists.qt.nokia.com/mailman/listinfo/qt5-feedback >>>>> >>> _______________________________________________ >>> Qt5-feedback mailing list >>> [email protected] >>> http://lists.qt.nokia.com/mailman/listinfo/qt5-feedback >>> > >_______________________________________________ >Qt5-feedback mailing list >[email protected] >http://lists.qt.nokia.com/mailman/listinfo/qt5-feedback _______________________________________________ Qt5-feedback mailing list [email protected] http://lists.qt.nokia.com/mailman/listinfo/qt5-feedback
