What I need is a function for Non Earth Coordinates in QGIS (both projects and layers). They should be mappable to any projected coordinate system (like SWEREF99TM).
Why: In the Mining industry we often use Non Earth systems for different reasons. Like Geophysics we want to define North in a convenient direction. Could be South East we don't care about the real world at this stage. The same if an ore body is going south-east we may define that direction as north.
In many softwares (Microstation or MapInfo) we use we can have on the fly conversion between lets say myCoordinateSystem1 (cartesian system) to EPSG3006 no problem. But I have not found a good function for this in QGIS.
I wonder if the Proj4 limits QGIS so you can't do this? Any solutions for this?