[Qt-qml] Node/Graph interface

[henrik.hartz at nokia.com]

Hi Jo,

On Apr 6, 2010, at 2:17 PM, ext Johannes von Bargen wrote:

I am designing a cool new concept for user interfaces, mainly loosely based on mind-mapping / nodes / connections between nodes. To get an idea of what I am talking about you could check out iMindMap<http://www.imindmap.com/articles/files/lightSound.jpg>, Blender node-editor<http://blenderzin.de/media/0texturnodeskd3.png>, Maya Hypergraph<http://www.djx.com.au/blog/wp-content/images/layeringShadersInMR/layersHyperGraph.jpg>, SoftImage RenderTree<http://xsisupport.files.wordpress.com/2010/02/blinn_rendertree_connections.png?w=548&h=258> etc. Similar interfaces are found in every compositing/effects tool.

My plan is to bring this approach to the daily desktop use, preferably integrated with KDE.

I am a web developer with allmost no desktop programming experience, but the declarative way of doing things with qml catched me.

What I need:
* Boxes/Nodes of arbitrary shape

Rectangle or Image would serve you well here

* Splines

We don't have splines or lines in QML, save for the Path View which allows you to represent a model rendered by delegates on a defined path (http://qt.nokia.com/doc/4.7-snapshot/qml-pathview.html). You could potentially write this as QGraphicsObject elements composed of Painter Paths that you expose to QML (see also the pathstroke demo in $QTDIR/demos) and reuse the Path element. Perhaps you could ally with someone that has C++ experience and make these into modules that can be installed into QML?

For us, performance is a key limitation to what we can put in for now (e.g. we investigated an Ellipse item but didn't satisfy our own performance gate), but with Line/Spline implementations working well on Embedded platforms we could potentially merge in.

* Text on splines (following the curves)

The Text element should be easy to make work with a future Line/Spline implementation, x and y are properties that could be bound to a position animating over the Spline path.

* The possibility to use splines to connect nodes (or severals point on one node to some more nodes)

Looks like a detail of a Spline implementation.

Is there a fast and practical way to build such a thing in qml?

No, nothing in QML. But, I suggest you formalize this into a suggestion (in fact I've made http://bugreports.qt.nokia.com/browse/QTBUG-9687, feel free to comment!)

Cheers,
Henrik
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.qt.nokia.com/pipermail/qt-qml/attachments/20100408/6575c54c/attachment.html