True north in Geo-location

It took many years of confusion until I learned why the geo location terrain looks rotated in the model, and why geo locating changes the north angle. For those who don’t know, geo locating a model in SketchUp makes the model green axis match something called Grid North. I have personally never heard of Grid North outside of SketchUp’ geo location - not in architecture school, not in my internship, not in high school, not in elementary school. Grid north doesn’t even have a page on Swedish Wikipedia.

The idea of Grid North seems quite smart. If I understand it correctly, you divide earth’s surface in segments where you approximate the surface as singly curved. This allows two parallel lines to stay parallel, but at the cost of north jumping a few degrees when you cross the border between two segments.

The problem to me is that Grid North just doesn’t seem to be widely used here. Every time I’ve geo located a model and imported a DWG plan, site plan or city plan, it has been oriented with True North as its Y axis. Every time I’ve had to either rotate it to match SketchUp’s solar north direction (with some custom Ruby snippet for precision), or reset solar north to 0 and also rotate the terrain/map snapshot accordingly.

I propose making geo located models use green axis as True North, or at least make it an option when geo locating. Not only would this make my life easier, but it would also lower the learning curve and be a lot easier to make sense of as it follows the principle of least surprise.

Who knows, maybe simplifying this also makes the SketchUp devs’ life easier.


Related threads:

I’m not the first person to be confused by the grid north noise.

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Here’s another for the list…

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Maybe it’s a vestige of how Google Earth satellite photos were tiled as images onto SketchUp models? Of course, with that feature gone, why stay married to it. Does the new system need image tiles or something dictating this?

Google Maps uses true north so it would have been simpler to just stick to that in SketchUp from the start. I don’t know why they went through the extra problem of using another north in SketchUp.

Hi, I also mostly work with survey data that is written to Sketchup through FME translator. In this case the TrueNorth angle is needed to be applied to the written sketchup model for relevant terrain cutout area to match the 3DCityModel of Stockholm.

Looking at other 3D software programs e.i. 3dsMax, I’m just spawning ideas of how most of them do not work with geo-located coordinates, as the purpose is mostly to model object based models (charachters, assets, details etc.). So you have to world coordinate origo that every object relate to and then you can set local coordinate to each object’s orientation in 3dsMax. Same as 3dsMax, you can model object based models in Sketchup as well and then you’re probably well with GridNorth.

If I understand it right, TrueNorth in Sketchup is also for getting accurate shadow analysis for geo-location all around the world?
So depending on model purpose in Sketchup, maybe it would be good to have a switch button between GridNorth vs. TrueNorth?

I found this discussion link pretty interesting too for north angle in sketchup: