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Blender ac3d export axis confusion  

Postby rebootl » Wed Jun 12, 2019 8:55 pm


Sorry if this has been asked before but I couldn't find anything.

I'm very very confused by the axis conversion provided by the export plugin "Majic79 addon" (

And I have a very simple question. :D When I simply orient my model in blender to the FG CSYS. What do I have to select in the export options to get the export "right" for FlightGear?

Which would be -X axis along the plane and Z up as defined by:

Using the logical settings for the plugin Forward -X and Up Z doesn't result in the right orientation. I went so far as to comment this freaking matrix out in the python code and got it right at some point... but this can't be it.

This _has_ to be documented somewhere and I will put it in the wiki as soon as someone tells me the settings :cry:

Sorry for the rant, and thanks in advance.

Edit: Okay, I think i figured it out by trying/luck. It seems that Forward -Z and Y Up does the trick for a model oriented in the FG CSYS.
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Re: Blender ac3d export axis confusion

Postby WoodSTokk » Wed Jun 12, 2019 11:12 pm

If i'm looking from top view, the aircraft point to left.
So in my case:
Back/Tail = +X
Front = -X
Right = +Y
Left = -Y
Top = +Z
Bottom = -Z

At exporting there are the settings:
Forward: -Z Forward
Up: Y Up

I have never changed this settings, so i think that default settings.
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Re: Blender ac3d export axis confusion

Postby Necolatis » Wed Jun 12, 2019 11:33 pm

Yes, the default settings will make the axises similar to FG.
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Re: Blender ac3d export axis confusion

Postby rebootl » Fri Jun 14, 2019 3:26 pm

Aah, yeah. That explains why it worked the first time. :D
Then i must have changed the settings for some reason...

I think i'm still gonna add a note to the wiki.
Thx <3
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