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(FS9) Are there any limitation in Frames of animation through CAT?


Resource contributor
Dear Arno,
I'm making animations for VTBS airport. I've made a lot of animation at 500 frames and export to FS9. They work just fine. I decided to put these animations through CAT to make animation varies through diffent type of aircrafts, diffent lenghts and heights. But I've go
"Runtime error '9: Subscript out of range."
I 'd to know the maximun frames we can put throught CAT. Anyhow we can do something about this?
I also attached this VDO to clarify what I'm doing with animations.


There should not be a limitation on the amount of frames you can use in your animation, I have processed animations with up to 1024 frames.

How many keyframes do you have? Is there one at every frame? That might be a problem, but I would have to check that.
Dear Arno,
I have two FMCs, two catering cars, one bag car with 4 trailers with about 15 keyframes. May be all of them are not animated at the same key frame. I'm not sure if it is the problem but each type of car has exactly the same key frame. Do all the animated cars need to be on the same key frame?
You said that you have did 1024 frames for animation. I have problem with that too. I never do animation that long since when I do animation more than 800 frames, gmax refuse to export. There is some error but I can't remember what it is. I already adjusted frame rate to 20. Eventhough SDK tell us to do at 18 frames/sec but there is no option to do that.
Thanks for the reply,

The animation speed is always 18 frames per second, that is fixed due to the timer used by FS.

When the animation keys do not match between different objects you should get a warning message, not a crash like you describe.

Maybe you can email me the files you are trying to convert, so that I can reproduce things here?
Thank you very much. I really appreaciate your offer to help.
I'll try to do something to solve this problem which I think I know what is the cause of it.
If I go to the dead end, I'll will send you the gmax file that I'm working. :(
Dear Arno,
I think I have come to the dead end. I've checked all the moving models and parts, all the keyframes are the same. There are 15 keyframs in this animation and 40 moving parts. I have check exactly 600 points of keyframes (15X40) and they are fine. CAT still refuse to take this file.
I've tried to upload file but it is too big (3.4Mb). May be there are too many moving parts. I think if that is the problem, I can save to same type of cars and put together in one animation. FMCs will go to FMCs animation and Foodcar will go to just only Foodcar animation. I have tried this plan and it worked! But there will be a lot of work to do through CAT and a lot of file for each type of airplane.
Thank you for your help. I really need someone to help with this before I get more grey hair or get new eyegrasses or going insame!.
Best Regards,

Can you email me the ASM files you are putting into CAT, plus an overview of the settings you used? You can send them to arno _AT_ fsdeveloper _DOT_ com.
Dear Arno,
I have e-mail my Gmax file already. Would you mind take a look at it? I have come to the deadend since my "Plan B" doesn't work out. The vehicles I separately export to mdl runs wildly in FS9. The stair is up before it reach the point, catering car runing with its tailer up. Plan B doesn't work at all.:confused:
Best Regards,

I ran your file in the debugger and found the problem. It is not allowed to have more than 50 animated parts in your scene. It seems you file has more of them, i guess that must be the most complex animation put in CAT ever :D.

Technically it should be possible to fix this bug, but I have not maintained CAT for years now. So getting the compiler, etc running correctly again would take some time. So I would advice you to receive the amount of animated parts. Or maybe you can split the file into two MDL files?
Dear Arno,
Thanks you for checking my file. I have done what you said, split it up. Actually I've done 3 mdl's for each type of car. It works fine when I do just only FMCs. But when I complied the catering cars, things got urly. Catering cars moves wildly, sometime running with the container up and down.
I think may be I have to do more none animated parts to make CAT accept my file. You don't need to fix your program since no one will be such a crazy guy like myself to do such a lot of animation! I have to admit that. Anyway, thank you so much for checking my file.
PS. Looking in VDO clip is fun but it is not possible, I'm going to cry.....I'll try again.
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The animation that goes crazy, does it run fine before using CAT? That would be the first thing I would check :).

The animation that goes crazy, does it run fine before using CAT? :).

Yes, of course, like the vdo I posted. But I separately selected just one type of car and export to mdl, not making a whole new Gmax file.
I think I'll attach something together in Gmax to make less moving parts. May be this works.
Dear Arno,
It works right now. I attached something together to make less moving parts and CAT accepted it. I've seen that my stair car does not move well. I did what you said, checking it before get it into CAT. The stair car doesn't move well either. May be gmax export does not handle well with angle rotation, since when I remove rotation of the stair along its axis (to rotate it from resting position before the upper part extend to reach the level of the aircraft door), it works just fine.
After that I tried to animate catering car. The plan is when I put parking break, the car will come and the container will be raised up and stay right there. When the parking break is off, the container comes down and the car moving back to its original position. I have done this through CAT using the second page only (apply to triger), the car moves fine, the container and the mechanics arms work fine. But on the way back after remove parking brake, the mechanic arms are not moving right. One pair of the arm move back to horizontal position first and the second pair of moving arms rotate to horizontal and the container move down. Disapointed by this, I then change my plan to apply CAT to animation, make it move continuously. Are there anything I can do to correct the inproper-backward-moving parts? Since the are controlled by CAT.
Thank you for your time to help me
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What CAT does is that it reverses the animation keys for the backwards animation. Until now I have always seen that that works fine. For transformations it should, but for the quaternions of the animation I can image that in certain cases it is not working OK. Maybe you just hit such a special case.

If you want I can take a look at the code or else you could try to change the animation slightly and see if it works better after that.
Sorry for delayed reply.
Thanks a lot for your offering to check. But I've done all the things in the simplest way. It works now and I applied CAT to the animation not the triger since if I do apply to the triger I have to separate file for FMC which runs continuously. That will give me a lot of grey hair and wrinkle on my forehead.