Will Fusion ever get tweening or onion skinning?

Onion skinning is already in the animation editor click the arrows near the bottom scroll bar

Since Fusion uses bitmaps and not vectors for its images it is very unlikely that it'll have tweening support any time soon. However you could look into interpolating your animations through external 3rd party means like Dain-app: Please login to see this link.

I haven't used it myself but it seems to get fairly smooth results. Remember though, you can make really good animations with just a few carefully crafted frames

Fusion doesn't have onion-skinning, unless there's an option somewhere I'm not seeing. Onion skinning involves being able to see multiple frames at once (ie. as if drawn on thin, translucent 'onion skins' that are superimposed), so you can better judge the smoothness and pacing of an animation. Usually, frames in the past are shown in red, while frames in the future are shown in green, like this:

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Not multiple but previous or next frame [MENTION=15682]Volnaiskra[/MENTION]

oh wow - I had no idea! I always thought that little scrollbar was used for moving through frames. Good to know!

Looks like it can show you just one extra frame at a time. That would definitely have its uses - especially with lining things up - though it's still a bit limited. One of the benefits of onion skins is being able to see - with your mind's eye - the arcs of your animation, as well as its pacing. So in the example above, the woman's arm moves in a simple and graceful arc (arcs almost always look best in animations), which would have been much harder for the animator to achieve without onion skinning. Also, just by looking at all those red/green frames at once, you can see the pacing: the arm starts off slowly down the bottom, then speeds up, then begins to slightly slow down again as it moves towards her face (meanwhile, the wrist lags behind the arm until it quickly snaps back in the final 6 or so frames). By seeing these many layers as you work, it's a lot easier to keep your pacing working as inteded.

By the way [MENTION=6335]twister[/MENTION], have you seen the Spriter Pro tool on the clickstore? I've never tried it, but it seems like it would give you onion-skinning, tweening, and more: Please login to see this link.

Spriter Pro has onion-skinning and tweening: Please login to see this link.
Spriter extension has integration of tweening in CF2.5.

I assume it has onion-skinning based on this picture (from the clickstore page). Those red shadows look like onion skins to me (although they seem pretty much identical to the main figures, which is a bit weird):

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As for tweening, I guess it depends on what you mean by tweening. Back when I used Macromedia Flash, it had 2 types of tweening: shape tweening, and motion tweening. In both cases, it would use the vectors from the head and tail frames, and interpolate the in-between frames accordingly. In the case of shape tweening, it would actually morph the shape of the vectors, whereas in the case of motion tweening, it would merely move/rotate/scale them, keeping their fundamental shape unchanged. In both cases, it would essentially create the in-between frames for you, and you could then edit those frames yourself if you wanted.

My guess is that Spriter might not have that kind of tweening, where it actually creates in-between frames for you. Actually, having lots of animation frames is expensive (RAM-wise), and I think one of the purposes of tools like Spriter is to reduce the amount of actual graphic frames you need. To achieve this, I think Spriter uses the concept of bones, which is similar but different to tweening. So you "rig" your character up with bones (1 bone for upper arm, 1 for lower arm, 1 for neck, 1 'bone' for head, 1 'bone' for hair, etc.), and then you can tell Spriter to move the bones however you like. For example, you tell it to start the leg in a back position and end in a kick position, and it will perform the in-between animation states for you automatically. If it supports Inverse Kinematics (which I think it does) then it'll go even further: if you tell it to move character's fist from next to its ear to straight out in front of it (ie. a punch movement) then it'll automatically straighten the elbow and adjust the upper-arm and lower-arm in a realistic way, without you having to do anything to those bodyparts yourself. But all if this is likely to take place programmatically, at runtime. It won't actually create any PNG-based graphics within the Active Object that you can view in Fusion's animation editor.

I want to stress again that I've never used Spriter, so I'm just speculating based on the screenshots I've seen and on how other animation tools I've used do it (I use Toon Boom Harmony). But I guess my point is that it might be worth your while to look into Spriter's "bone" features, though they might not work exactly how you had in mind.

Quote from twister

But, the whole idea would be to reduce the number of frames in the animation, by adding the inbetween frames during runtime which does not seem possible.

As I understand it, that's exactly what the Spriter Pro extension does, isn't it?

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