This will be the first of an on-going series of Flipbook tutorials created by animator Andre Quijano. The tutorials will cover a variety of exercises and fundamentals that animators, of all skill levels, learn and practice to improve their process and understanding of motion with traditional 2D animation. This lesson will focus on the Bouncing Ball exercise. Feel free to start from scratch or open one of the accompanying demo files. Example1 Example2 Example3 Example4
STARTING A NEW FLIPBOOK To get started, you ll need to select New FlipBook under the File menu in SketchBook. This will open a Settings window where you can choose canvas size, frame rate and number of frames for your flipbook. The settings used in this exercise can be seen in the image below. *Flipbook is a tool only available in the Pro level of Autodesk SketchBook.
FLIPBOOK TIMELINE Here s a breakdown of the Flipbook timeline once you ve chosen your settings. On the left, you have your frame creation controls: Add a keyframe, hold frame, duplicate frame, and delete frame. In the middle is the working zone where you choose which frame is active. The slider at the bottom of the window sets the number of frames visible, and the total length of the animation. On the right you ll find controls for playback and ghosting frames, also known as onion skinning. The layer editor will also change a little in Flipbook mode as there are only four layers per frame. These layers are a solid background color, background, midground and foreground. Only the midground and foreground can be animated on; the background layer is a still image, in this case a table.
STARTING A NEW FLIPBOOK It s important to experiment and play around with how you want your workspace layout to be setup so that you can work comfortably. For this tutorial, the default pencil tool was used. I ve set the size to 10.0 by double clicking on the icon and editing the Brush Properties. Don t be afraid to be sketchy and rough with your lines, it s the motion we are after. The first step in this animation exercise is to select the background layer and draw a line across the canvas creating a floor that will serve as the ground plane for our ball to bounce on.
WORKING WITH KEYFRAMES The major points of motion in an animation are called keyframes. Keyframes are the base images that you need to describe the story you re trying to make. For this exercise, we will start by creating three keyframes. First we set where our ball starts from above the floor. Now, select the second frame to sketch where the ball makes contact with the floor. It can be a little difficult to recall the original position of the ball, and that s where the ghosting buttons come in handy. Turning on ghosting frames allows you to preview the frames behind or ahead of the current frame.
INBETWEENS AND TIMING One more ball is placed the ground on a third keyframe. Now that we have our keyframes drawn, we can add more frames in between the keyframes. These frames are known as inbetweens. It should be noted that we cannot just add frames in any order, as you need to consider timing of the bounce. With careful timing you can create a more convincing sense of motion just by drawing one object s place next to another. When a ball is dropped, you can see how the force of gravity takes affect. The ball will initially pick up speed and when it hits the ground, the ball will bounce and push itself back up. Have a look at Example2_Acceleration, or take a look at the.gif Here and see a clear difference using timing between two bouncing balls A and B. KEYFRAME 1 INBETWEENS KEYFRAME 2 INBETWEENS KEYFRAME 3
INBETWEENS AND TIMING Now we can start adding frames inbetween keyframes 1f and 2f. First, click on frame 2f and click the icon to insert an empty frame. Then add a new frame by clicking the icon. A good way to start is by using ghosting to sketch in the midpoint between both of the existing frames. As the ball drops, it should start out slow and pick up speed as gravity pulls down on it so we ll add two more frames; one between 1f and 2f again and another between 3f and 4f.
REVIEW You can experiment with adding additional frames to get a feel for the motion. There is another way to draw frames without having to press so many buttons by turning on the Auto Keyframe feature. Let s click and drag our third keyframe to the right, leaving plenty of frames in between and select the next empty frame in the timeline. With Auto-Keyframe active (highlighted in red), you can skip the step of adding a Keyframe after selecting an empty frame. In other words, you can draw inside a blank frame to reduce the number of clicks, making it easier to animate.
REVIEW Once you have sketched in a series of frames, press Play in the playback controls (or press Enter ) to watch the magic unfold as you have created a bouncing ball animation. Congratulations! Try playing back with loop turned on to see the ball bounce over and over. Now you could go back and clean up the frames or add more frames to smooth out the motion, but that s up to you. Hopefully you have gained the feeling of creating motion. You should have something similar to Example 01.gif *Click on the image below to open the file in a new tab in your browser.
ADDING DIRECTION A stationary bouncing ball is a great start, but how about with animating with movement? Try creating a Flipbook that shows the ball moving from one side of the canvas to the other. You could also try making the bounce get lower and slower as it loses momentum, like in the images below. Challenge yourself and experiment, but if you do get stuck you can check out Example3 and Example4.