Hi, I have roughly implemented approximate reprojection. It should work for GDAL and GRASS, I have not tested WMS. Currently it is always using approximation (even if error is too big). Rendering with reprojection takes about 5 times more. You can get some info about times grepping debug output, e.g.: qgis rp.qgs 2>&1 | egrep "(time|CPMatrix size)" | sed 's/.*cpp: //'
I have got for example for reprojected raster in raster providers branch: 89: (QgsRasterProjector) CPMatrix size: mCPRows = 5 mCPCols = 9 41: (readBlock) create projector time (ms): 10 53: (readBlock) read not projected block time (ms): 24 71: (readBlock) reproject block time (ms): 1022 1287: (draw) raster draw time (ms): 1446 1287: (draw) raster draw time (ms): 10 the same raster not reprojected in raster providers branch: 1287: (draw) raster draw time (ms): 323 in trunk: 1830: (draw) raster draw time (ms): 689 It is strange that it is slower in trunk. > On Thu, Jan 13, 2011 at 7:06 PM, John C. Tull <jct...@gmail.com> wrote: >> Comparing the load time of this raster when the project CRS is the same as >> the raster (i.e., no transform should be occurring), the load time still >> requires several minutes. This is true whether or not I have enabled on the >> fly reprojection in the project options. In contrast, the same file takes >> several seconds to load in trunk. Are you talking about loading the raster first time or about redrawing? Maybe statistics are not necessarily computed. Radim _______________________________________________ Qgis-developer mailing list Qgis-developer@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-developer
