Hi guys,
I'm struggling with the default for interpolation, which keeps changing! I started with animating the lip sync, so I used a lot of 'step' interpolation. Then I changed to animating the general movement (walk cycle) but the program still uses 'step' interpolation as default interpolation instead of smooth. I noticed the 'K' icon in the timeline and tried to change the interpolation there. But to no avail!!! I still have to change each individual keyframe from 'step' to 'smooth'. That's really annoying. There must be a better way!
Please, please help!
How can I change interpolation default?
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- Hugging_Bear
- Posts: 106
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How can I change interpolation default?
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Re: How can I change interpolation default?
I just set the Mainline's default Interpolation Mode to Copy Previous Key and forget it.

This way, the mode for any channel is based on that channel's Interpolation Mode in frame 0.
For example, if you have one item's keyframe at frame 0 set to Linear, then every new key that follows will be linear. Then, if another item has its interpolation set to Smooth at frame 0, then every new key that follows in that channel will be Smooth. With Copy Previous Key, every channel can have its own default interpolation mode.
Also, if you change the interpolation mode for an existing key in any channel at any point in the timeline, then any new keyframe created after that will use the new interpolation mode. This system is very flexible and minimizes the need to keep changing modes during animation.
Once I start my animation stage in a project, I hardly ever need to change the interpolation mode because each item's default mode has been determined during rigging.
It takes only a little extra work up-front to make animation in Moho much easier and faster.
Bonus tip: For Smart Bone Actions, I always keyframe frame 1 inside the action. This is because in some situations, I may want to use Linear within the Action's animation, but I want to use Smooth or Step in the Mainline. I can have both by keyframing and setting interpolation modes for frames 0 and 1. (Frame 0 will be the default for the Mainline animation, and frame 1 will be the default for the Action's animation.)
Hope this helps.


This way, the mode for any channel is based on that channel's Interpolation Mode in frame 0.
For example, if you have one item's keyframe at frame 0 set to Linear, then every new key that follows will be linear. Then, if another item has its interpolation set to Smooth at frame 0, then every new key that follows in that channel will be Smooth. With Copy Previous Key, every channel can have its own default interpolation mode.
Also, if you change the interpolation mode for an existing key in any channel at any point in the timeline, then any new keyframe created after that will use the new interpolation mode. This system is very flexible and minimizes the need to keep changing modes during animation.
Once I start my animation stage in a project, I hardly ever need to change the interpolation mode because each item's default mode has been determined during rigging.
It takes only a little extra work up-front to make animation in Moho much easier and faster.
Bonus tip: For Smart Bone Actions, I always keyframe frame 1 inside the action. This is because in some situations, I may want to use Linear within the Action's animation, but I want to use Smooth or Step in the Mainline. I can have both by keyframing and setting interpolation modes for frames 0 and 1. (Frame 0 will be the default for the Mainline animation, and frame 1 will be the default for the Action's animation.)
Hope this helps.

Last edited by Greenlaw on Fri Nov 29, 2024 10:27 pm, edited 6 times in total.
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Re: How can I change interpolation default?
Another tip: When I'm using Smart Bone Actions, I typically use Linear keys inside the Action's animation. This ensures that any item I animate will stay In sync with the other items in the action. This can prevent weird timing problems in the Mainline. (Maybe this explains the 'walk cycle' problem you asked about in the other thread? Just a thought.)
As mentioned, I set frame 0 to be whatever Interpolation Mode I expect to use during animation. For most items, this would be Smooth, Step, or Linear, but it can be anything.
As mentioned, I set frame 0 to be whatever Interpolation Mode I expect to use during animation. For most items, this would be Smooth, Step, or Linear, but it can be anything.
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- Hugging_Bear
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Re: How can I change interpolation default?
Hi Greenlaw,
Thank you for your quick and very helpful reply!
I'm afraid it's too late to try this for this current project. But I'll definitely try this in my next project. But that won't affect layer-animation. Because sometimes one wants the layer to move in 'smooth', sometimes in 'linear' interpolation.
So, how do I determine the interpolation mode of a future bone? The same way, I can change the interpolation of a keyframe?
Thank you for your quick and very helpful reply!
Do you mean that I have to set the preferred interpolation mode before I'm adding a bone? I never thought about this. I usually hide my timeline window when I rig a character because for me, rigging and animating are two totally separate work modes/stages.Once I start my animation stage in a project, I hardly ever need to change the interpolation mode because each item's default mode has been determined during rigging.
I'm afraid it's too late to try this for this current project. But I'll definitely try this in my next project. But that won't affect layer-animation. Because sometimes one wants the layer to move in 'smooth', sometimes in 'linear' interpolation.
So, how do I determine the interpolation mode of a future bone? The same way, I can change the interpolation of a keyframe?
The Guardian of Tales - YouTube Channel
https://www.youtube.com/@guardianoftales
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- Hugging_Bear
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Re: How can I change interpolation default?
That's very unlikely. I only used smart dial bones to control the facial expressions of the character. That won't affect the movement of the legs or arms.(Maybe this explains the 'walk cycle' problem you asked about in the other thread? Just a thought.)
The Guardian of Tales - YouTube Channel
https://www.youtube.com/@guardianoftales
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Re: How can I change interpolation default?
I usually use Smooth for most channels, which works well for many situations, and preset only the few channels to Step or Linear as needed. The modes can be set anytime for any bone.Hugging_Bear wrote: ↑Fri Nov 29, 2024 11:13 pm Do you mean that I have to set the preferred interpolation mode before I'm adding a bone? I never thought about this. I usually hide my timeline window when I rig a character because for me, rigging and animating are two totally separate work modes/stages.
I think new bones always default to Smooth until I change it. I've never had to think about that before now, so this is probably correct.

I set the different Interpolation Mode for any 'non-Smooth' bones at frame 0, but there's a trick to it: Moho won't let me set it at frame 0 unless a keyframe exists later. So...I just create a temporary key on the timeline, which reveals the key at frame 0. Now I can set the Interpolation at frame zero, and then I'll delete the temporary key. When I delete the temporary key, the key at zero will also disappear, but it will retain the new Interpolation mode as its default.
If you want to do a bunch at once, just Freeze Pose on frame 1 to reveal all the keys at frame 0, and set the modes down the line as you wish. You can delete the Frame 1 keys after making your changes.
Alternatively, I might set my frame 0 Interpolation Mode while I'm setting up my Smart Bone Actions. As mentioned earlier, I always set a keyframe at frame 1 in my Smart Bone Actions, and this reveals frame 0. So when it's necessary, I use this opportunity to set my Interpolation mode for the Mainline. When I switch back to the Mainline, the 0 key may disappear, but the new default Interpolation Modes have been set for items used in that Smart Bone Action.
I hope this doesn't make it sound more complicated than it is. To summarize: set the default mode in the Timeline's list to Use Previous Key; then, set the Interpolation mode for any key at frame 0 (i.e., Linear, Step, whatever,) and this will become the default interpolation mode for that channel.
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- Hugging_Bear
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Re: How can I change interpolation default?
Thanks again Greenlaw!
Setting the interpolation mode to 'Step' before creating a step-bone worked fine for me. But then after changing back to a smooth-bone I got again a step-keyframe each time.
But I forgot to set a keyframe at frame 0, which just didn't happened naturally because fame 0 is not part of the animation (it's there for creating and rigging layers). I guess there is a trick to do it anyway with force freeze keyframe. But as you rightly said, it's a bit complicated. I guess, it's a matter of integrating this step into own's workflow in order to prevent more hassle later.
Setting the interpolation mode to 'Step' before creating a step-bone worked fine for me. But then after changing back to a smooth-bone I got again a step-keyframe each time.

The Guardian of Tales - YouTube Channel
https://www.youtube.com/@guardianoftales
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Re: How can I change interpolation default?
Leave Interpolation in the main Interpolation Mode drop-down list set to Copy Previous Key. When you change the interpolation for the keys, use right-click on the keys. This will make Moho use the previous key's mode as its mode. BTW, there was a brief example of this in the tutorial I uploaded last week. (Around 8:58 mark.) It's not a full tutorial on the topic, just a quick demo, but it may be helpful to see how it works.
To change the key at frame 0, make a key on frame 1 (you can double-click on the timeline to do this), and a frame will appear on 0. Now, you can set that interpolation to whatever you wish by right-clicking over it, and it will be the default mode for that channel only. You can delete the key at frame 1 after that.
It's pretty easy once you get the hang of it, and well worth doing because it makes animating in Moho much easier.
I typically set my frame 0 when I'm working in a Smart Bone Action. I typically want the Smart Bone's animation to use only Linear, so I set that mode at frame 1, and then I'll set 0 to whatever it needs to be for the Mainline. Usually, that's Smooth, but sometimes it needs to be Step or Linear.
Hope this helps. I'm going to add working with Inperpolation Modes to my list of tutorial to create.

To change the key at frame 0, make a key on frame 1 (you can double-click on the timeline to do this), and a frame will appear on 0. Now, you can set that interpolation to whatever you wish by right-clicking over it, and it will be the default mode for that channel only. You can delete the key at frame 1 after that.
It's pretty easy once you get the hang of it, and well worth doing because it makes animating in Moho much easier.
I typically set my frame 0 when I'm working in a Smart Bone Action. I typically want the Smart Bone's animation to use only Linear, so I set that mode at frame 1, and then I'll set 0 to whatever it needs to be for the Mainline. Usually, that's Smooth, but sometimes it needs to be Step or Linear.
Hope this helps. I'm going to add working with Inperpolation Modes to my list of tutorial to create.

NEW! Visit our Little Green Dog Channel on YouTube!
D.R. Greenlaw
Artist/Partner - Little Green Dog
Little Green Dog Channel | Greenlaw's Demo Reel Channel
D.R. Greenlaw
Artist/Partner - Little Green Dog
Little Green Dog Channel | Greenlaw's Demo Reel Channel