[Qgis-developer] Raster rendering difference tracked down

[Tim Sutton]

Hi Peter

Thanks for the update on this.

Regards

Tim

2008/7/14 Hugentobler  Marco <marco.hugentobler at karto.baug.ethz.ch>:
> Hi Peter,
>
> Ok, looks like it is an issue introduced by me. I will investigate.
>
> The raster scale factor for rendering should always be 1.0 in the main map canvas (it is different only for map composer).
>
> Regards,
> Marco
>
>
>
> -----Ursprüngliche Nachricht-----
> Von: qgis-developer-bounces at lists.osgeo.org im Auftrag von Peter Ersts
> Gesendet: Mo 14.07.2008 16:47
> An: QGIS Developer Mailing List
> Betreff: [Qgis-developer] Raster rendering difference tracked down
>
> Tim and Marco,
>
> Here is a little update. I have tracked down the difference in rendering
> behavior, which is causing the two units tests to fail, to revision
> 8440. This was the merge into the trunk of the Render Context Branch.
> More specifically, I believe the difference has to do with the scale
> factors that are being computed in QgsMapRender.cpp.
>
> As it is right now, I will say the test results for the landsat_basic
> looks like it has artifacts compared to the expected result in the area
> being marked as different. However, when you load the original raster
> data for the landsat_basic test and 'Zoom to best scale' the displayed
> result does not exhibit any artifacts. So I think the next logical place
> to start digging around is the QgsMapRender->setExtent() and looking
> more at the scale factors, unless anyone has other ideas.
>
> -pete
>
> --
> ====================================
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> American Museum of Natural History
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>
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-- 
Tim Sutton
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