On 30 May 2018 at 20:57, Mark Johnson <[email protected]> wrote: > I have the impression that when in the main QGis Canvas only a geometry > (with QgsMapTool / QgsVectorLayer) is being changed, only the geometry is > being refreshed and not the underlining Rasters (which have not changed). > > I would like to know how this is done since I am working with an adapted > Georeferencer with QgsMapTool / QgsVectorLayer for the points, where when > the Pixel-Point is moved in the Georeferencer-MapCanvas both the geometry > and the Raster are being refreshed, which when multiple points need to be > moved is quite time consuming. > > I have looked through the QgisApp, QgsMapTool, QgsMapLayer/QgsVectorLayer > classes but I fail to see what is being done differently. > > If an hint could be given where this done, I would be grateful.
Is this within a separate QgsMapCanvas? If so, look into the options: QgsMapCanvas::setCachingEnabled() QgsMapCanvas::setParallelRenderingEnabled() QgsMapCanvas::setMapUpdateInterval(); It might be worthwhile copying the code from QgisApp::applyDefaultSettingsToCanvas so that the same settings apply as do for the main canvas. Nyall _______________________________________________ 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
