Is it possible to measure when QGIS starts and stops loading/rendering a layer?
I used something similar in OpenLayers before (loadstart and loadend event, http://dev.openlayers.org/examples/layerLoadMonitoring.html ) but haven't figured out yet how to do that in QGIS with pyQGIS.
I want to use it in order to measure which layers take long to load (geometry and attributes!).
I know that there is something that can be used outside of QGIS to benchmark loading times ( https://github.com/DMS-Aus/qgis2img ) but
a: the loading times of layers in QGIS were way longer than the values measured by the tool. I guess that tool doesn't read the attributes.
b: I would like to measure the loading times inside QGIS
I think that that there has to be something that already listenes to something like a loadstart and loadend signal as in the statusbar there is an indicator that is shown until the layer is loaded completely: