Problems with AC3D 4.0

[INNIS]

Hi Guys
This is my first post on the forum unfortunately it is a problem.
I have used AC3D for about 6 months to make and change
aircraft models for the open source flight sim flightgear.
In 3.6 I had no problems.
But I find now with 4.0 every time I go to use a model saved
from 4.0 I get this error on sim startup.
FATAL: ac to gl:unrecognised token 'crease 45.0000'
This occurs even if I do nothing to the model other than
resave it.
If I then replace the 4.0 created model with its 3.6 equivalent
model all works perfectly again.

Any help would be greatly appreciated.I dont want to go back to
3.6 if I can help it

Thanks in advance

cheers
Innis

[Razer]

4.0 handles curved surfaces better so this might have caused a problem with the sim.

you have any info on flightgear? url?

[Dennis]

"crease" is keyword in 4.0 files that refers to the new feature supporting crease angles. It looks like ac_to_gl doesn't like seeing keywords it doesn't recognize in the AC3D file format, and is choking on this one. I'm assuming this tool will eventually be upgraded to support version 4.0? You may need to contact the author to make this happen.

In the meantime, if you're experienced in C/C++, you could edit your copy of the ac_to_gl source file to include the "crease" keyword.

Barring that, a hack-ish way to do it would be to make a copy of the .ac file from version 4.0 in a text editor and remove any lines from the AC3D file that begin with "crease" before running ac_to_gl on it.

I definitely wouldn't recommend this as a permanent solution, but it'll allow you to continue using 4.0. You won't be able to take advantage of the crease feature in any models you export (and it's a very nifty feature), and it's just a general pain to do this for every model, anyway. But it would be worth a try at the very least to see if it works for you until the ac_to_gl utility is upgraded.

[INNIS]

Thanks Dennis for the detailed explanation.
I will ask about it on the flightgear board.
I am afraid my C knowledge would not fill
the back of a postage stamp.
I guess the only short term solution would be
to go back to the 3.6 version until flightgear
upgrades.

Thanks for the replies.

Cheers
Innis