Hey all, I'm a big fan of the open source community because of the way information and learning is shared so freely and quickly and because the outcome of open source projects is usually quite excellent. Sharing ideas and collaborating with creative people really motivates me and helps me learn as well. I've been thinking a lot about how to apply the open source mentality to the animation community and finally it clicked. Share the info with others, the same way, duh! So here goes, I want to start by reviewing the animation principles and what better way to start then the ball bounce.
The two biggest things that we learn from a bouncing ball are the principles of timing and spacing. These two are essential to creating animation, they are quite literal in their names, timing deals with the amount of time it takes for something to happen. Spacing deals with the space between drawings or frames. The way you adjust the spacing within a given amount of time will have major effects on the way we perceive the movement. Experiment and play with your timing and spacing to see what happens and pay attention the the results! :)
Ok, a ball bounce is the perfect way to start thinking about animation. The best way to figure it all out is to reference the real thing and take notes on what you see. Make yourself aware of the arcs or path the ball follows, the speed of the bounces, listen to the sounds, time it out and write it all down. Picture it in your head and see of you can simply imagine that bounce, think about the change in force as gravity and inertia work their part and the ball eventually stops. How does it come to a stop, does it stop suddenly, does it roll backwards as it comes to rest? If you don't know, go back and watch it again and write that down.
To animate it, we will want to start at the most logical place, the beginning. To work through your animation it is best to start with the beginning and the end in mind, these two things are key to the process.
Start by figuring out your timing, we work at 24 frames per second which means a 2 second ball bounce will require 48 frames total. (The drawings will actually hold for 1 extra frame each, this is called working on “2s” so of the 24 frames, we only draw 12 different drawings.) Put your first drawing at frame 1 and your last drawing at frame 48.
Next, draw the contact points for each bounce, this gives us all of the “key” frames. Without these drawings we can't express a bouncing ball, they have to be there and so this is the best thing to start with. It's also why their called key frames.
Something I learned about painting that seems to apply to anything I work on is to start big and work down to the small. So paint in the sky then the large shapes of the background and the different objects, working from big shapes, down to smaller ones until you finally get down to the detailing of individual things. This is true for animation too, the larger shapes are those key drawings and from here we will work our way down through extreme drawings or drawings that are pretty key and work off of the key drawings and then down to inbetween drawings that go between the keys and extremes. How do you eat an elephant? Yup, one bite at a time!
So the next step then is to add the ball at the tops of each arc, these are breakdowns and give us the full idea of how high each bounce goes. We are starting to see a nice pattern here and if we were to just go ahead without thinking it might seem natural to just add more balls, evenly spaced to fill the rest of the frames. So, this is where all that watching, thinking and note taking comes into play.
Remember the timing. When I observed a ball bouncing I saw that the first bounce took almost one second and the following bounces happened quicker and quicker. So, the timing should reflect those exact bounces. I tend to think of it in sounds and rhythms so in my head I play out a thunk...... thunk.... thunk... thunk.. thunk. I used a stop watch to time it so I'm referencing my notes on the timing while also thinking about that rhythm. My first guess at frame 24 was off and so I moved it over a bit, ahhh, better :)
Ok, we have some timing figured out and some basic spacing as well. The spacing going forward is going to really help us show the weight and mass of our ball. Drawings that are spaced more closely together will appear to move slower than drawings that are further apart. A ball could zip through the screen with only two or three drawings spaced far apart or slowly crawl cross the page by using many drawings spaced closely together.
When I observed the ball bouncing I noticed that the ball slowed down as it went up in the air and then sped up again as gravity pulled it back down and so forth. So I will use closer spacing on the drawings at the top of the arc and further spacing as the ball falls to the ground.
Finally I'm looking at the rest of the inbetweens. I'll be keeping in mind the spacing as it relates to the movement. I like to start kind of mathematically here, then making small adjustments based on how the bounce seems to feel. Here is my final spacing after making a few more adjustments and what the bounce looks like animated :)
Next time we will look at squash and stretch on a bouncing ball :)