What is the best way to draw on top of geographic maps (QWebView)?

Question

Qt

Good afternoon.
There is a need to draw primitives (rectangles, polygons, lines, etc.) on geographical maps that are displayed through QWebView. What is the best way to do this? Through QPainter, or do it through javascript? If through QPainter, how to convert display coordinates to map coordinates? Or is it better through javascript? Here, in principle, there are no difficulties, but in this case, will it slow down a lot?