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Jerky Prop Animation in FSX

Skip67

Skip67

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ireland
Hi, has anybody experienced jerky prop animations in FSX ? Is it just me or is this a fault in FSX ? I cannot get my C152 prop to animate smoothly when seen in FSX, I had keyframes at 0 25 50 75 100 then I increased that to 0 12 25 37 50 62 75 87 100 but it's still jerky in FSX. Can anybody offer any advice ?

Many Thanks.

Skip
 
Skip,

Welcome to the wonderful world of FSX and the department of 'silly prop animations'.

If you find a way to make them animate 'properly', please let us know.

:D


Its pretty much a bug and not something you did. If you go through FSX and look for a plane with smooth animations, I believe you will not see one. For some reason, they animate one way, then stumble, sometimes reverse, then back to the proper direction again.


Bill
 
Every FSX model I've ever done has extremely smooth prop0_still animations...

I simply key-frame animate 0 to 100 keys:

0 = 0º
50 = 180º
100 = 359º

I then manually set additional keys every 10 frames:

0 10 20 30 40 50 60 70 80 90 100
 
lionheart said:
ahh... 'Still'.. Thought we were talking about 'blurred'.
Click to expand...

It doesn't matter, Bill! The same technique works for _still, _slow and _blurred... :D

As for the _slow and _blurred, only the _blurred is of any consequence, as the _slow literally won't be seen for more than oh, 0.001 seconds or so... :)

The way that it sometimes appear to spin "backwards" is a result of "strobing," and can be seen in real life as well. Just stare at a box fan's blades as you adjust the speed control...
 
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I'm puzzled why you have 100=359 degs? You do that on wheels, too?
 
mjahn said:
I'm puzzled why you have 100=359 degs? You do that on wheels, too?
Click to expand...

Interesting point.

Could it be sufficient to tell FSX a keyframe range from 0 to 60 for the prop/wheel animation in the Animation Manager?
 
mjahn said:
I'm puzzled why you have 100=359 degs? You do that on wheels, too?
Click to expand...

I just knew that would draw a raised eyebrow! :D

Yes, I do that for any rotation/keyframe situation that calls for 360º, including a 3d compass.

Frame count starts at ZERO, so "360 frames" = 360-1 = 359 keyframes...

In all honesty, no one would ever "notice" a one-frame "error," but the purist in me... no, make that anal retentiveness... forces me to be "exact!" :rotfl:
 
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Heretic said:
Interesting point.

Could it be sufficient to tell FSX a keyframe range from 0 to 60 for the prop/wheel animation in the Animation Manager?
Click to expand...

Only if you don't mind rewriting the XML script(s) for the prop and wheel rotations! :eek:
 
Frame count starts at ZERO, so "360 frames" = 360-1 = 359 keyframes...
Click to expand...

As you will have anticipated, this has got me more puzzled than ever.

The frames range is 0-100, isn't it, so I don't understand your referring to "360 frames" at all.

Whereas the degrees range for a full circle is 0-360, not 0-359. If it were 0-359 then the compass rose section from 359.1 .. 359.9 wouldn't or at any rate shouldn't be covered.

Could well be though that FS extrapolates the missing degree, ie smoothly moving from 359 to 360/0 without anybody noticing.

In which case Heretic's surmise might actually be correct?
 
mjahn said:
Whereas the degrees range for a full circle is 0-360, not 0-359. If it were 0-359 then the compass rose section from 359.1 .. 359.9 wouldn't or at any rate shouldn't be covered.
Click to expand...

Zero-degrees and three-hundred-sixty-degrees are co-incident with one another. They represent the exact same point on the compass rose.
IOW: 360 = 0

FS's variable returns only integer values, so decimals aren't a factor at all.

My previous reply was a bit ambiguous, as I was thinking in terms of a custom XML entry where 360 keyframes has been declared as normative.

However, the same principle holds even with only 100 keyframes, where frame 100 would be keyed for 359º of rotation.

In the final analysis, the induced "error" is of no great consequence. I'm sorry I even mentioned it now... :o
 
I find that after creating intermediate keys the actual degree values assigned in gmax (as seen in the PRS controller window for each key) are rarely what you expect them to be, ie if you have 0 degrees at key 0 and 180 at 50, then 10, 20, 30, 40 aren't as you might expect 36 each but some fractional value. It is possible, however, to adjust these values manually to read what they logically should, ie 36, in a ten interval scale, or 90 in a four-interval scale for a full 360 degrees revolution. So far I have not been able to detect any awkward side effects using the latter scale (0-25-50-75-100) with manual adjustment to make sure each interval gets its 90.0 degrees.

Whether this is germane (or should I say German?) to the issue I will leave to your own experience and experimentation. Strobing is fine, but stuttering could certainly be related to these factors - the sim trying to catch up on a lost degree or so, especially if it handles integers only, as Bill says. (Truncated or rounded?)

Just an idea.
 
What's your system skip?

I used to get gerky prop animation a few systems ago but it seem to have gone away with my newer systems. Perhaps it is just a performance issue.

Therefore as mentioned the strobing effect becomes uglier with lower frame rates perhaps, just a guess since I don't have anything to test it with.
 
Blogga said:
What's your system skip?

I used to get gerky prop animation a few systems ago but it seem to have gone away with my newer systems. Perhaps it is just a performance issue.

Therefore as mentioned the strobing effect becomes uglier with lower frame rates perhaps, just a guess since I don't have anything to test it with.
Click to expand...


Thats interesting. I hadnt heard this before.
 
Strobing also leads to users mistakenly thinking the prop turns the wrong way. As yours truly did recently with a DH.103 Hornet...:o
 
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