[Qgis-developer] Approximate reprojection for vectors

[Martin Dobias]

On Tue, Nov 1, 2011 at 12:30 PM, Marco Hugentobler
<marco.hugentobler at sourcepole.ch> wrote:
> Hi Martin
>
>> btw. the feature cache from #3200 is based on R-tree.
>
> Wow, cool!
> One question to the feature cache patch (didn't yet look into the code in
> detail, so maybe a silly one):
>
> Reading the usage notes of the QgsFeatureCache class, it seems to me the
> implemented strategies are optimised for desktop scenario where user loads a
> scene and then zooms in.
> In a wms server scenario, it would be nice to cache features in the tiles most
> viewed by visitors (e.g. parts of the city rather than countryside), but the
> zoom-in scenario is less likely in a webgis. Is the code in the patch  already
> optimised for the web-scenario or is it necessary to implement a new
> mode/strategy?

The usage scenarios were indeed directed to browsing with map canvas -
new strategies should be added for different scenarios. Anyway we
should revisit the design to make sure it still fits well the
architecture before doing some serious work with the patch.

Martin