The 'colour edges by axis' feature ...

leedeetee

Well, I could be completely wrong, but this feature seems fundamentally flawed, has anyone else had any issues with it?

I have drawn a building, I thought I'd use the edges coloured by axis for ease(!). The original edge of the wall is vertical, as indicated by the blue 'coloured by axis' edge.

The face wasn't acting in a co-planar fashion, so I drew a vertical line from the bottom of the building.
This also is blue so 'coloured by axis'.

HOWEVER there is a 5.2mm gap between these two lines, so they BOTH CAN'T be Vertical?!?!

So, it's basically not worth using 'colour edges by axis', then?

Two vertical lines.

Wo3Dan

@leedeetee said:

....HOWEVER there is a 5.2mm gap between these two lines, so they BOTH CAN'T be Vertical?!?!....

Yes they can....if there's some tolerance allowed to show off axis lines this way.
This is IMO something that can't be avoided.

Example:

draw a vertical line from the origin up, 10 meters. The line is on the blue axis, its top is at [0,0,10000]
draw a new line somewhere on the ground, starting in the origin. Now with nothing selected you can move the other vertex and send it to either:
[0,9.9,10000] or [0,-9.9,10000] or [9.9,0,10000] or [-9.9,0,10000]
All of these lines will still show blue, although the top is 9.9mm displaced from blue in either green or red direction. This seems to be the maximum tolerance in described situation.

You should see 'display edges by axis' as an aid. But even then only if you created your geometry by taking advantage of/relying on the inferencing engine.
I have to admit that in some ocasions I encountered this issue but it's very rare.
If you for instance import inaccurate geometry from say AutoCad you may see this happening more often.
You have to remember that there is no way to do without tolerance. It might have been smaller but still...
See attached model.

'display by axis' tolerance for 10m edge on blue