MOMENTUM 101

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Momentum! aka INERTIA

      Always remember my advice and views are just one possibility. Chocolate might not be the best ingredient for every cake... This post is less of a lecture but more of a bunch of tips put together that have helped me out over the years. 

     When animating things move you must establish a force. Ask yourself: what is making this object/body-part move? Can you 'see' that visually?
For example: if you are observing a body is walking across the screen you could ask yourself: what is making it move? You answer: The legs. Can you see it? Are the legs moving the body realistically?.....

     Believable Animation always dies when things move for just the hell of it. When your object moves realistically, the viewer then has the freedom to observe the story/character instead of wasting time figuring out why the animation looks so weird.

small ball vs. BIG BALL
     Heavy objects take longer to accelerate and decelerate but they can move just as fast as anything else. (the ease in and ease out will just take more frames!)
      Now for CG animators we have to translate this knowledge into the all mighty graph editor (DUN Dun dun) That might sound like a scary task so I made a cheat sheet for you. Some teachers might just say, go explore the graph editor and figure it out for yourself. Why waste your time when i have the answers right here. Leonardo Davinci would have his students copy to learn! And they all ended up as great accomplished painters in their time.
      Below check out how the small ball has short ease in and ease outs. Smaller things usually have less mass which equals less momentum when it's moving around. Heavy objects will have longer ease in ease outs.

On the left is the graph editor for the small ball and the right side has the graph editor for the heavy ball. 

MORE TIPS
-Make sure anything pulling something heavy has a 'straight' line in it
-In a walk cycle: heavy spends more time at the bottom

The Balloon Exercise 
-will challenge you to: animate something light with little momentum, perfect your bouncing ball skills by forcing you to animate the same pattern upside down. Animate a ballon bouncing across the ceiling!

Remember this is just like a bouncing ball but upside down. 

Shapes
         When looking at your animation you should be able to pause it and still see what direction the momentum is going in the object that is moving. Moving your characters and objects around isn't the whole story. You must construct appealing shapes that communicate where the momentum is going. The silhouette can say so much about what direction your object is going.

You should always tell where the mass is at in soft objects. 

-Just in case I didn't make it clear enough, here are the definitions of the concepts I am typing about.

MOMENTUM from wikipedia
In classical mechanics, linear momentum or translational momentum (pl. momenta; SI unit kg m/s, or equivalently, N s) is the product of the mass and velocity of an object. For example, a heavy truck moving fast has a large momentum—it takes a large and prolonged force to get the truck up to this speed, and it takes a large and prolonged force to bring it to a stop afterwards. If the truck were lighter, or moving more slowly, then it would have less momentum.

Issac Newton on INERTIA
"The vis insita, or innate force of matter, is a power of resisting by which every body, as much as in it lies, endeavors to preserve its present state, whether it be of rest or of moving uniformly forward in a straight line."

GRAPH EDITOR: when you are panicking

Animator specific post...

     Graph Editor Tricks that I have found my self using. One is for when I am animating in stepped and the Other trick is for when I'm animating Layered. (stepped is when your graph editor does not allow your splines to curve and keeps looking like steps, layered is a way of animating when you FEEL the animation and its timing from the root out)

     I'm not here to debate which way of animating is better, I'm not about to regress into a school girl type of shouting match. I'm just going to give two tricks I find my self using often and the help me out a lot. Actually.. they've saved my ass more time than I care to admit :)


     So.. lets say you are animating Layered, so happy that you are getting results super fast and you even dare to think you might actually finish before the deadline. But soon you perfect start disappears and soon you animation is muddy, your timing is wrong, your takes melt into each other and nothing is left of your initial timing! You were almost done but now you don't know what to do. There are hitches in the arms, the nose arcs and you even discover you have problems in your root! What are you going to do?

What I do is:

I do hope this makes sense. The numbers at the bottom are frames on the time line.

     So I kind of start over but keep my 'blue print' of what my animation once was. I use the buffer curves (ghost curves) to guide me. I go through each curve pretty fast and double check its right and working well with the curves before it on the hierarchy. Doing this process saves more time than actually trying to fix everything while all the body parts are moving. And most of the time you don't even know that the curves you are fixing are responsible for the pops or bad timing in the first place. So that's why once you remove all the curves from sight and slide them back one by one, you easily come across the bad curves that were messing everything up. Its a bit tedious but it goes by fast. and you know once you are done, you have done everything you could have done and that leaves you feeling satisfied.


     The other situation where I use one of my tricks (well I wouldn't call it a trick, its more a piece of advice) is when I'm animating in stepped. Usually I'm pretty far along with my animation and I'm ready to start splining and making my curves smooth when I realize when that making my curves smooth is LOOSING all my timing etc. Now I'm faced with a choice: Do I continue smoothing out my stepped curves and FIGURE it out like how us good little animators were taught?? Or do i say fuck it and just keep animating in stepped?

I say Fuck it!... bad choice of words danny.. bad choice..

     BUT DANNY why would you animate like that? I don't make this decision out of laziness all the while as I am adding breakdowns I have my eye on the graph editor watching the curves FORM as breakdowns and poses are added and added. once I can see the curves develop more defined, then I will start to clean them up (all the while in stepped) Eventually my animation will be on 2's 3's and 4's here and there. This method keeps my timing and I spend more time animating than fighting with the graph editor. I never allow my graph editor to become messy and I never ignore my curves. I baby sit them the whole way still using as little controls as I can while getting the most out of them.

    These are my methods, they are not wrong, they are not right, but they allow me to finish my animation. It works for me and I encourage that if these methods do not seem to help you, you will search for a way that does. Many times I see a lot of great blocking and Ideas turn into mush and then becomes forever lost in the graph editor.


    Internship deadlines are coming fast in the spring, I wish all of you who are applying to places the best of luck and happy holidays! I guess I should mention here that I will be trying out tutoring after the new years. Not online tutoring but a real legit person to person hands on tutoring. I'll see how it goes. It might be cool it might actually be a utter complete business failure :) I'll do a post in a few days with more details about my plans for this... experiment!

GRAPH EDITOR: Off Setting 101

This post is for animation Students but hopefully it gives some insight to non-animation artists for those who are looking for it.  
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Dear Curves,

Die.

-A Student
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      I could write 100 blog posts about the graph editor (graph editor is a tool animators use to move and adjust their characters in the computer. ) but no amount of lectures will substitute raw first hand experience. You have to get frustrated and go through your OWN epiphanies. In my experience with the graph editor I have come across a few tricks/understandings. In this post I will share one of my understandings with you. I will keep it short for I find when something is over explained, it can make a simple subject very confusing.

OFFSETTING in animation:
      -When you break up the moving parts of the body to help show that there are different muscles working at different times to achieve one giant general movement. In the graph editor that just translates to: shifting your curves so that they all are not working at the same time. This is something everyone knows but its tricky to get it to look RIGHT/or ORGANICALLY in your animation for someone who is still learning.
      My tip is, even though we are taught that when things start and end at the same time is bad, TECHNICALLY under the hood (graph editor) it needs to happen at some level. If you look below you will see a very simple turn. (All we will focus on is the body and the head). When you first offset a curve it might look like the example on the lower left hand side of the page I have provided below. Most new students will leave that as is and then wonder why their animation has hitches and pops. You must remember that EVERYTHING moves on the human body at the same time, but somethings move more than others; which gives the illusion that somethings are not moving at all.

My drawings of the curves might not be accurate but its the concept I am trying to get across. 

     So do you notice how my curves will start moving at the same time? Though the curve for the head 'takes off' before the other curve for the head does. The body curve is moving at first but only very very slightly, then it slopes up to catch up to the head curve. When you make the curves harmonize and 'wait for each other' before coming back to a 'flat' stop, it will help with making your movements feel less mechanical and broken. 
   
EXTRA TIP for a head turn: Using counter animation to your advantage. If you look at the next picture, you will see a situation where you are forced to use counter animation.

       Below: Is how that curve will look in the graph editor. Notice how the 'hump' in the head curve doesn't extend the amount of frames needed but works within the frames given. in maya terms: All you need to do is set a key 3/4th of the way through the head turn and then raise it up in the graph editor.

     I can go more into why I believe these tricks work and, how should i put it.. I can talk more THEORY on the subject but I shall leave you with the solid basics and spare you the dense explanations. Try experimenting with these curves yourself. Adjust according to your needs. My drawings are not accurate to real situations but the curves are drawn only to get the point across. Take my tips and make them your own, you might discover better ways to accomplish what I'm trying to teach here. My way by far is not the right way or the only way. I do hope this helps for those that might be struggling with their fundamentals.

-Danny