Animation question, feel like an idiot...

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Brief question about animating a moving character...

Am I right in thinking you should animate a characters position from the root/COG rather than the master controller?

I've spent more time than I'm comfortable with admitting over the past week trying desperately to block in a walking character using the master controller to block in the overall forward movement... which resulted in sliding feet and a lot of headaches trying to figure out why.

So am I supposed to just leave the master where it is and then move the character with the root, so regardless of where the character goes the master control always stays put?

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  • Valerien
    What do you intend to do with your animation ?

    If you're making game animation, cycles etc., you should use the root controller to move your char then once your anim is finished clean it so your character runs into place.

    If it's for a cinema-like shot, it will be easier to work with the hips instead, to keep a natural workflow.
  • System
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    Thanks, yeah I should've mentioned its for a scene/film style rather than a cycle for a game engine.
  • MiAlx
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    MiAlx polycounter lvl 7
    Teejay, i had the exact same problem at first. In my experience it really depends on the camera shot. If you have a full body shot of a walking character, then leaving the global move or master controller where it is and animating the position with the COG or root is a bit better (imo) since you don't have the sliding feet problem, but you then have to handle a lot of data at once (on the other hand, when isn't this the case :D).

    Something that was of HUGE help to me, because it simplifies the walk workflow:

    First look at the distance that the char has to walk. Sometimes i even put a nurbs curve from where the character starts to where he stops, just to have an overview of the line of movement. Then animate the character's down pose only and try to fit it to the distance he has to walk. Like Frame 1 then Frame 12 then Frame 24 then Fame 36 etc.

    Then fill in the space with the passing pose. Then the down pose inbetween those. Then the contact. Then if you had the curves set to stepped, spline them and smooth them out and tweak them (if necessary). Like this:

    nongamewalk.jpg

    You probably already know this workflow, but I just thought i'd share it with you.

    here's the source btw: http://www.anticz.com/Walks.htm

    enjoy!
  • System
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    Thanks so much MiAlx that's indeed a great help.

    I must admit it's a real head-tester. I first learned to animate walk cycles on the spot, where everything was very 'formulaic', for example if the first down position is on frame 5, then the opposite would be on frame 21 in a 32 frame cycle etc. This is all easy to work out in a cycle, but the general consensus for doing 'moving/non-cycling' walks is to block it in just like any other animation at which point the whole formula and set timing seems to go out the window but at the same time you need to retain the formula to some extent to keep the walk looking somewhat natural.

    It's also so much harder to talk about this rather than actually do it but it can be really confusing trying to figure out a balance between the maths of which frames should hold which poses, and timing it visually without thinking about it from a mathematical point of view.
  • System
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    Man. I don't get this at all. Animating a walk not using a cycle may well be the most difficult thing ever.
  • MiAlx
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    MiAlx polycounter lvl 7
    Yea, I agree and I know very well what you mean. It takes tons of practice to get it done right and looking natural. I still have often trouble with these kind of walks, some times I have to delete the whole walk and start over. It's a pain. :D

    When animating Cycles.. it's far less painful.
  • System
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    I just don't get it. There's so many questions I have!

    I'm trying to animate a character from standing, so I'm not starting with the extreme, which adds to the confusion.

    Should you match up values on every pose for every stride? So on the first down position, let's say the foot rolls up by '2', then should you match that value for every subsequent down position.

    And lastly, how the hell do you figure out how far the feet are supposed to move in each stride. Does it even stay consistent?

    The annoying thing is that this is all technical aspects. I'm not even at the stage of looking at weight and arcs and all that good stuff, because I can't even block the damn thing in.

    It seems so easy when I talk about it but then I get into actually making it and it's a nightmare!
  • Mark Dygert
    When animating the character through the scene instead of doing an in place walk cycle it helps to have IK on the feet so you can lock the feet in world space and keep it from slipping around as you move the root node/COG. Various rigs do this in different ways normally there is some kind of pivot placement you can also animate to help the foot "roll" as it transitions from heel to toe.

    So which app are you using? (sorry if I missed that)
    Which rig are you using?

    Normally when animating through a scene, I lock down the back foot. Position the front foot like taking a step to contact. Move the COM (Center of Mass) so the stride looks right, set keys and clean up.

    I work with walk cycles with 4 poses Contact, Recoil, Passing, High Point, then these get reversed (paste opposite in biped) to complete the other half of the cycle. Move COM, paste, Move COM, paste, wash rinse repeat until you have what you want. I went into the 4 poses in a bit more detail here: http://www.polycount.com/forum/showthread.php?p=1320395#post1320395

    Another method is to save out an in place cycle, then use animation layers or a motion mixer to blend the COM movement with the cycles. The great thing about 3dsmax's motion mixer is that you can blend animations so a walk transitions to a run, a run into a jump and jump into a land then a walk again. This is also great because cycles can be saved out and applied to any biped so as an animator you build up a library of things you can edit/splice together. Maya finally got its act together and introduced something very similar, HumanIK. Which is pretty much the best parts of MotionBuilder and Biped combined into one plug-in. Not only leg and arm IK but full body IK. Really awesome rig but it has a few draw backs and is a bit buggy, hopefully they'll work out the kinks. Even if they don't I see a lot more people using it for games.

    Another handy feature in biped and CAT is you can create procedural walk cycles adjusting prameters like stride width and length, speed, hip swagger ect. In biped you can place footsteps and it will animate along them. You bake that down use it as a base to animate with. You can also delete the keys on the COM and you have a pretty decent start at an in place walk cycle.
  • System
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    Thanks Mark.

    I'm using Maya, and just a simple ball with legs rig: http://www.mattornstein.com/downloads.html The IK locking is working ok, the feet stay put when you move the COM around.

    So would you move the COM from point to point first, so where it starts, to where it wants to be at the end of the shot, or would you move it, pose an extreme, move it again, pose an extreme etc?

    I'm sure I'm making this harder than it is but if anyone's got a spare minute, go try it. Animate a character from standing still, into a 4 step walk forward, back into standing still. To me right now, that seems like an impossible feat!

    I looked at the Trax editor but to be honest, I think I'd rather do it by hand so I can tweak the little intricacies in weight shift or add slight variations if necessary. I suppose you might be able to do this with layers/trax editor but it kinda seems a bit 'hands-off' to me.
  • MiAlx
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    MiAlx polycounter lvl 7
    In a vanilla walk, the root moves from start to end in a linear movement. So that means that you should do that too. You set key 1 at the start key 2 at the end and set the tangents of the root's translation to linear, like this (sorry for the crappy gif):
    stepone.gif




    So this will give you a good feeling if something is off.

    You should not set the exact same values, since then it gives you a robotic feeling, because of twinning. But you could start off with the same values and then change them, it depends on how you like to work.

    About the feet, i found a good quote:
    We do not walk with our legs. We walk with our mind and our torso. When we walk, we aim to move our body (or our face, or our behind) from one place to another. Also, when we watch a person walking, we concentrate on their face or their torso. As long as their legs don't do anything so unusual that it demands our attention, we just assume that they're doing their job the way they should.
    It's more of an eye thing. Keep the character in balance and check pics like that to see how poses could look like and the get a feel for the distance of the feet from the body:

    1_walk.gif
  • Mark Dygert
    See post below... I iz grud editar of postz...
  • MiAlx
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    MiAlx polycounter lvl 7
    oh wow, Mark, I didn't see your post when i started writing mine. You covered it pretty much, your post was helpful for me too. :D
  • System
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    Heh thanks guys, big help.

    It's a lot of work this animation lark eh?!
  • Mark Dygert
    ^ Yep that's pretty much the 4 poses I use. Notice that A and E are the same just opposite.
    TeeJay wrote: »
    So would you move the COM from point to point first, so where it starts, to where it wants to be at the end of the shot, or would you move it, pose an extreme, move it again, pose an extreme etc?
    Pose an extreme, pose an extreme and crawl through the scene that way.

    Well let me back up first I would block it all in. To do that I animate just the COM maybe with some poses (set to step curves) to get a sense of speed, timing and when the big poses are roughly going to happen.

    Then once I know where and when those will be taking place I crawl through the animation roughing in most of the poses, not really spending too much time cleaning it up or tweaking curves because at this stage things can change which would blow those tweaks out of the water.

    Then once things are mostly roughed in and the timing looks good I get to work refining and tweaking it. We call them passes at work.

    1st pass: blocking with step curves, gets the ideas out easily and lets people visualize it, very easy to tweak and edit.
    2nd pass: roughing in the approved block in pose for pose.
    3rd pass: Refining and tweaking.
    4th pass: Throwing it all out and doing it all over again because Design, Marketing, QA or someone higher up decides that what they approved should be different. lol
    TeeJay wrote: »
    I'm sure I'm making this harder than it is but if anyone's got a spare minute, go try it. Animate a character from standing still, into a 4 step walk forward, back into standing still. To me right now, that seems like an impossible feat!
    well I think you should work on just a walk cycle, through the scene is easier and normally how I do my "in place cycles but I just delete the forward keys on the COM, heh. Doing a transition from standing to walking can be tough, you have to dig into how does the motion start and how does it transition into a cycle bla... that's a lot of junk to think about once you have a walk cycle down it becomes a bit easier.

    In animation its almost always working backward knowing where you're going then animating to get to that point.
    TeeJay wrote: »
    I looked at the Trax editor but to be honest, I think I'd rather do it by hand so I can tweak the little intricacies in weight shift or add slight variations if necessary. I suppose you might be able to do this with layers/trax editor but it kinda seems a bit 'hands-off' to me.
    The Trax editor in Maya is pretty limited and not very helpful in the few times I've tried to use it like Motion Mixer. You're better off not using it unless someone has a very specific use that is illustrated very well.

    With the addition of HumanIK to Maya it has a much more robust animation blending and re-targeting system which is much more like Motion Builder (a separate autodesk mocap clean up and animation program) and Motion Mixer in max.

    Another advantage to HumanIK is the auto rig functionality, if you don't have a skeleton it can analize your mesh and generate one for you. HumanIK might be pretty scary at first and look like a lot of features but its well worth knowing how it works not only for workflow speed and flexibility but it's how a lot of other apps handle animation and it makes understanding and transitioning that much easier. I'm not suggesting you scrap what you have and go nuts on HIK but at some point its worth checking out.
  • Mark Dygert
    opps meant to edit my post and ended up replying again...
  • Valerien
    Study the principles, force, weight using different resources, there are many books, tuts and articles available out there. Richard williams's animation survival kit is well known in the industry for example and covers walks in depth.

    http://www.animationarena.com/

    Then shoot reference, and analyse the motion with sketches. You should carefully plan your work in order to get good animation.

    I don't really know why everyone says the walk is that difficult to make, because body-mechanics wise, you can find plently of more complex motions... maybe because this is one of the first motions you need to do well in order to go on in animation, or because it can be tough to give it a precise, recognisable mood... yet it's the first character exercise we did at AM.

    Good luck anyway.
  • Mark Dygert
    Valerien wrote: »
    I don't really know why everyone says the walk is that difficult to make, because body-mechanics wise, you can find plently of more complex motions... maybe because this is one of the first motions you need to do well in order to go on in animation,
    I think that's it. I remember it as one of the harder things to master mostly because it was one of the first things I did even though its the simplest thing for me to do now and I've done a lot harder since. I wish I had started off with something that had less moving pieces.

    Also... belittling the persons struggles doesn't really help them it just frustrates them more than they already are. Recognizing that it can be a challenge for a someone just starting out and empathizing while encouraging and helping them, tends to go a lot farther, or so my experience goes...

    Like Valerien said observation is king. Shane Kelly has a great free e-book available which pretty much stresses and reinforces this.
    http://www.animationmentor.com/resources/ebooks/ (start at the bottom)

    Richard Williams The Animators Survival Kit is another great resource and he spends a lot of time on walk cycles. There are a lot of great visual examples.

    Also don't be afraid to read up on 2D animation so much of 2D applies to 3D and gets at the core of what it is to be an actual animator. Much of the 3D help and tutorials are what buttons do and how the apps work which seems like 99% of animation in the beginning but once you dig in you find its maybe 25%.
    Valerien wrote: »
    or because it can be tough to give it a precise, recognisable mood... yet it's the first character exercise we did at AM.
    Isn't the first few exercises at AM a sack of flower or a ball with a tail? I didn't think they threw people right into walk cycles?
  • MiAlx
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    MiAlx polycounter lvl 7

    Isn't the first few exercises at AM a sack of flower or a ball with a tail? I didn't think they threw people right into walk cycles?

    Yes. Bouncing balls and balls with tails. Not walk cycles.

    And still animating in a scene where its solely about practice (i.e. you do a walk from x to -x) is less challenging than having to combine it with a previous motion, plus all the acting that comes with the walk and before the walk (if there is any). For instance, when the character walks in a diagonal direction, between x and z after doing something. So yea, for me, walks can become sometimes a pain and sometimes a joy, depending on the scene/shot/rig.
  • melviso
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    melviso polycounter lvl 6
    There is a trick to this,using reference materials especially video clips could help immensely.Get video/movie clips of people walking from a standing position,e.t.c or better yet film yourself or a friend doing these motions and watch the clips,slow the playback to a point where the movie plays frame by frame and count roughly how many frames is needed to get a certain motion going.This practice will help u build very quickly a mental library of how many frames are needed for different types of motion both fast and slow,simple or complex and how they ease in and ease out.
  • Valerien
    Isn't the first few exercises at AM a sack of flower or a ball with a tail? I didn't think they threw people right into walk cycles?

    Sure, as I said, it's the first character exercise. And no, I don't mean to belittle TeeJay's work, otherwise I probably wouldn't have tried to help. I was just wondering why it is being pointed out as the most difficult exercise.
    Also don't be afraid to read up on 2D animation so much of 2D applies to 3D and gets at the core of what it is to be an actual animator. Much of the 3D help and tutorials are what buttons do and how the apps work which seems like 99% of animation in the beginning but once you dig in you find its maybe 25%.

    Plus don't hesitate to sketch a damn lot. Poses, gesture drawings, eventually drawings based on real moving people... it's ideal to train your observation skills, as long as you study how force works (Michael D mattesi - Force : dynamic life drawing for animators).
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