In CINEMA 4D keyframes are finessed using f-curves. In this video, learn how to manipulate f-curves to improve the motion of a ball bouncing down stairs.
- [Narrator] This is where we left off in the previous movie. And we have a ball bouncing down some stairs. What we want to do now is manipulate the keyframes we've created using F-curves. The F in F-curve stands for function. It can definitely be frustrating if you haven't quite got the hang of them, but hopefully after you've watched this movie you'll be totally fine with them. I'm gonna bring up the dope sheet here. And you've seen we've done that before. We've touched on this mode here. And this is where we want to be, F-curve mode.
So what I'm really interested in is the Y position for the most part. And also look at the X which should not be doing anything because it isn't traveling from side to side. And the zed is doing something as well which we'll look at later. You know what? Because the X is doing nothing, we can just delete that track. So select it and delete it. There's no point in having that extra data there if we don't need to use it. So, I like working with the timeline. Quite big, normally I have two monitors.
Another way of working would be to switch to the animate view and then you can get your timeline and your view here and it's all in one setup. You can switch back to the standard view and press Shift + F3, get up your timeline. Tab to go into F-curve mode, and just once again, highlight the Y position. We'll just scale this down a bit so that we can see what we're doing. So, the F-curve represents the interpolation between the keys.
And we can see we're getting a sense of that motion if we just follow it down. One thing that can be useful when working with F-curves is to create a snapshot of where you were and you can see what kind of progress you've made. So if we come to the F-curve menu here and choose Make Snapshot, Create Snapshot 1, and then we will say View Snapshot 1. Now, we won't be able to see anything cause it looks exactly like our F-curve at the moment. But as soon as we start manipulating points, and if I just zoom in and you can move using one and zoom in using two, it might be quite hard to see.
You can see that gray line there which is our original motion path. So, we will try and use it as a guide. So let's start by manipulating some of these handles. And all I've done, just like with splines which we just learned about, we can just select a point and grab a handle and move it around like so. We want to create a kind of bounce. So we probably want a different interpolation between these points. So we can use the Shift key to just drag one handle and affect that.
So we probably want this all to come down, bounce, and then bounce off quite sharply like so. So you can just change these handles. And now, because they're broken, we don't have to hold the Shift key every single time. We've just broken them once. So let's just go through, break the handles, move these up, just try and get a sense of what's going on. I'm just gonna work my way along using one to move the timeline. And we'll play it back and just see if we're getting any improvement.
And I think we are. I think maybe this is happening. There's a long gap here. It's kind of floating in midair. So, what can we do to fix that? As we saw in the first movie, we can actually change the speed by bringing the keyframes closer. So, an easy way to do that is to come back into key mode. I'm gonna just pause the playback there. And we can just use these buttons here as well to zoom out. And what I want to do is just select and drag a selection, a little box, around all the little keyframes I'd like to move.
And if I move my mouse up into the top part here, you can see the icon change. Now I can just move those back closer to that first keyframe. So I just come back into F-curve mode here, just frame that up a bit. You can also select a couple of keyframes and just frame the selected ones as well. Now, we can just modify the interpolation.
It's probably a bit too violent now. So I'm just gonna pause. Move this back, and you can see we're actually getting some more points on the spline here. And one thing we could do is use the zed value to make sure we've got our first keyframes selected. You could actually just change that value so it comes in a bit closer and just set a new keyframe.
So back in F-curve mode on the Y-axis, you can see that I had to keep fixing this point. And that can be quite frustrating and a bit of a waste of time as well. So if I choose Command + D and go to my Project Settings, go to Key Interpolation and choose this overdub mode, check that on, that should stop our F-curves from resetting themselves once we make changes. So it's also useful to note that you can turn that on. So I'm gonna go ahead and make a few tweaks to this and we'll come back once I've got it into a happy place.
So now if we play back through the animation, it's looking a lot better. And I had to go in and take out, oh, pretty much all the points on the zed. And you can see, if we just zoom in a bit, you can see that snapshot we took earlier of the zed has changed quite a lot and so has the Y as well. There's plenty to do. That's the thing about animating. If we come back out to the perspective view, we can see the ball is definitely bouncing down a bit better now.
There's a load of things that are missing from making this a really nice animation such as some rotation of the ball, some squash and stretch which would be achieved through scaling. So why not have a go and animate some of those properties using the methods that you've just learned? So the main takeaway from this is that we can take keyframes that we'd set previously, finesse them using the F-curve mode in the timeline.
- Setting up scenes
- Modeling with splines
- Using Illustrator files in C4D
- Extruding depth and detail
- Animating in the Timeline
- Creating clones
- Using effectors
- Lighting motion graphics
- Applying materials
- Creating animated materials
- Compositing multipass renders with After Effects and C4D
- Rendering motion graphics in C4D