Hi Steve, it is an interface-level customization thing, it's for people who are used to looking at coordinates and entering numbers while they are modeling.

It allows them to do all those modeling-time operations in the coordinate system of their choice, they basically don't have to try and re-learn which direction is "z" when they type in a point.

But it keeps compatability totally present by not changing how things are actually stored in files.

Each different kind of file format has a different convention for how things are oriented and MoI already does the necessary conversions into those different systems at export time.

If I changed the actual stored data when you changed the labels, it would break all those exports with a kind of "double transform" happening and it would cause all kinds of orientation problems with the exported data.


> You mention about applications giving the ability to flip/change
> axis on import, does that mean you will be adding such ability
> to the import of step/sat/iges files from application that do not
> use the same orientation as MoI?

Sure, if that is an actual problem that people are encountering.

But for example I can't remember ever seeing an IGES part that was not oriented with Z-Up, I'm not quite sure if it is absolutely specified to be that in the IGES spec but it is certainly the standard convention.

I've got some IGES parts from SolidWorks before and they seem to remap their coordinates to fit the standard convention there during their export.

Similarly they should pay attention to the standard convention of the 3DM coordinate system when they read 3DM data.

If I started exporting 3DM files with the actual data in it having the x,y,z axes in different directions than normal, it would come in as the wrong orientation in all the other 3DM importers out there that do properly follow the standard convention.

Except for in this one specific case, it would be a big transfer disaster to actually change the stored data when you changed your axis labels.

It is totally fine if another program wants to use a different coordinate system during their run-time, they just have to remap the data from the file's standard orientation to their own.

- Michael