I'm using QGIS 2.18.
I need to calculate the height of the rooftop of each building in a neighborhood. I have a vector shape of the buildings, with the building height attribute (from the ground to the top) and the shape of the contours (the height of the ground itself).
I need the information of the height of the ground of the centroid of each building and sum it into the height of the building in order to have the total height of the rooftop, in a shape of the buildings.
Here's a link to what I'm trying to do.