[Qgis-developer] Utilising QGraphicsScene in a first-class fashion for QgsMapCanvas

[Brendan Morley]

On Wed, 2007-04-11 at 08:25 +0200, Marco Hugentobler wrote:
> Hi Brendan,
> 
> This is very interesting. I have some questions:
> 
> What is your experience about performance and memory requirements of this 
> solution?

It works OK for me, but I probably don't ramp up the vertex count as
much as some (-:

> Am I right that the changes do not affect libqgis_core and libqgis_gui, only 
> the code on top of it?

Hmmm.  I've touched

QgsMapLayer and children
QgsRenderer and children
QgsComposerMap
QgsMarkerCatalogue
QgsSymbol
QgsLabel
QgsMapRender
QgsMapCanvas
QgsMapCanvasMap
QpsMapOverviewCanvas

My stupid question is, why does this matter to you?

>  Could you make a .tgz available so that developers can test?

Even better, try the attached diff against today's HEAD version.
Caution:
1. Try on a fresh checkout of r6883.
2. The only thing that really works is the Single Symbol render of
linestrings and polygons.  I haven't worked on anything else yet.


Good luck,
Brendan
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