QGIS 2.18.3:
I have a shapefile layer in QGIS which describes points. One class of points are ship lane beacon lights (svg image), and these should be turned towards the ship lane. The angle of the ship lanes are found in another layer (the shapefile line layer for the ship lanes) and the angle is in degrees with decimals (for instance 248.8000 ie 248.8 degrees).
It is possible to edit the layout rule for the SVG symbol, and there I can edit the rotation calculation. But how do I tell QGIS to use a field "ANGLE" in another layer "Shiplane" for the rotation angle?