[Qgis-developer] Qgis-developer] Rendering cache and labeling

[Giovanni Manghi]

Hi,


>> Suppose I have an uncached layer with labeling switched on.
>> During the first rendering, everything is drawn, including labels.
>> During the second rendering (same extent), the cache could be reused and
>> it would include labels previously drawn during the first rendering. No ?
>>
>
> No... the labeling is not cached anywhere. Therefore in every rendering job
> it is necessary to register all features that may have labels again in
> order to be considered in the labeling.
>
> Also think about this case: there is one layer with labeling, it gets
> cached. Then user adds another layer with labels - it is necessary to
> recalculate the labeling again as the new layer may require some existing
> labels to be hidden or moved to a different position to fit labels from the
> new layer. Hopefully that makes sense :-)


is this the explanation for this?

http://hub.qgis.org/issues/10441


cheers!

-- Giovanni --