Hi all With the recent addition of contour renderer of rasters I have realized there are artifacts coming to the renderer from the earlier stages (the raster data provider mainly). Another issue is that raster resampling (nearest neighbor / bilinear / bicubic) is only applied at the end of raster processing pipeline (i.e. after the contour renderer has been run), which does not really help for contours to get smooth contour lines (rather one gets some pixelated blurry output). Moreover, hopefully I am not the only one seeing occasional subtle "jumps" of raster data when zooming/panning map, which I would account to some small math errors in the QGIS raster code.
Looking at the GDAL raster data provider in QGIS, there's quite some code complexity, with copying of data between temporary buffers and dealing with limitations that existed in GDAL < 2.0 (e.g. non-integer source windows). I am wondering what people think about simplifying the QGIS raster pipeline: - get rid of the last stage of the pipeline - resampling - and make it responsibility of data providers (i.e. GDAL) to return resampled data - get rid of the reprojector stage of the pipeline - and again make it responsibility of data providers (i.e. GDAL) to return already warped data - any other raster data provider not being able to do it internally would just use GDAL routines My hope is that we could get rid of a lot of raster related code and at the same time use GDAL's optimized code even more. I am not saying I will be working on this anytime soon, but I would be interested to hear what others think about the current state of the raster pipeline :-) Cheers Martin _______________________________________________ QGIS-Developer mailing list [email protected] List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
