loopOut() script won't loop keyframes. Why?

[Rodan_Shiner]

Hello. I am using AE cs6 win version.

Right now I am trying to loop key frames using loopOut() expression, but it won't loop.

Please see this video.

Moving of The pale blue square is what I want, but if I use loopOut() expression to make such moving, it makes this green square movement. This green square has only 2 hold interpolation keyf rames on x position, and I just use default loopOut() expression. Seems green square's key frame 2 is ignored after first loop by loop expression.

Do you know why? Thank you in advance.

[Rick Gerard]

You will need 3 keyframes to loop hold keyframes. Just make the third a duplicate of the first. When you've got hold keyframes the loop looks for the first then the second but the second says stay here until you find another keyframe but your next keyframe in the loop has the same value as the first so there's no apparent loop. The 3rd hold keyframe will fix that.

Screenshots make questions like this much easier to answer than a movie of the result.

[Rodan_Shiner]

Thank you for your advice. So I need to make at least 3 keyframes to make a loop, right?

I made this loop. This layer has only 2 linear keyframes.

100 opacity on frame 0, 0 opacity on frame 2. This loop goes opacity 100,50,0,50,100,50,100,50,100,50,100,,,,,,

I wanted to make a loop like

100,50,0,100,50,0,100,50,0,100,50,0,100,50,0,,,,,,.

I am confused. I thought loopOut() makes loop from the time space between first and last key frames, but last 0 opacity keyframe is completely ignored.

Is it normal?

[Mylenium]

Check your behavior in the graph editor with the "use expression result" switch enabled and then add more keyframes to determine your loop. You are overthinking matters and only get confused.

Mylenium

[Rick Gerard]

You're over thinking and mis interpreting what constitutes a cycle. A 3 frame sequence with 0 at frame one and 100 at frame three will behave exactly as you're seeing. 100, 50, 0, 100, 50, 100, 50 because the cycle starts at frame when "cycle" comes into play and says the next frame has the value of the first keyframe. Now the cycle starts and the value for frame five is 50. Here comes the flaw in your thinking, and it's a common mistake anytime you create a loop. You want the loop to display the value of frame three before starting the cycle. It can't. No loop can unless you modify the loop behivior by changing the instructions or giving it another value. If the loop were to behave as you are expecting instead of as a loop works you'd have a keyframe value of 0 at frame 3, 7, 11, 14 instead of the desired 3, 6, 9, 12 and so on because the loop would be addative and not literal.

If you apply the expression from the Expression Language Menu AE would have given you:

     loopOut(type = "cycle", numKeyframes = 0)

This is a hint that there are different ways of controlling a loop. Whenever I see something that has variables I try and learn what they do. It was good advice from someone a long time ago.

Typing loop expression in the search field at the top right corner of AE brings up the Adobe Expression Library Index and looking down that page gives you a complete explanation of the usage of loopIn and loopOut. Here's the link.

So to summarize you can fix the problem by adding a 3rd keyframe with a value of 100 at frame four, or you can

[jgomula1]

Hi Rick,

I think I am having a similar issue. I am trying to loop a walk cycle whose comp is 32 frames. I have the loopOut(type="cycle",numKeyframes=0) applied. It does loop the walkcycle perfectly except at frame 33, where the second Time Remap keyframe is. At this frame the figure disappears completely - but this does not happen during any of the subsequent loops. Thoughts?

[Rick Gerard]

You have misplaced a keyframe or trimed the source footage 1 frame short. Take a close look at my previous post. Placement is critical for a complete loop.

[Rodan_Shiner]

OK thank you guys for your advice. I really hate this kinda programing thing and especially mathematics lol, so I get kinda allergy or something that blurs my mind.

I modified my loop and it works fine.I have to study it more.,,