Frame by Frame

Frame by frame animation requires the animator to individually draw every single frame with slight and successive modifications to each frame so that when played together, an illusion of motion is created. This is used for complex and high-quality animations where detailed and fluid movements are required, such as in character animation.

For frame by frame animations, each frame will need to be defined as a keyframe, as opposed to just a frame, so that you can add a separate image for each frame. A keyframe marks the significant changes in an animation, which include the beginning and end of a transition/action, while a frame simply acts as an intermediary/filler between keyframes. 

Image: Frame by frame animation using colour coded onion skinning, Image by Adobe (https://helpx.adobe.com/in/animate/using/frame-by-frame-animation.html)

Tweens

Instead of having to draw every single frame, tweening allows the animator to let the software automate the creation of the intermediate frames between keyframes. The most basic example of tweening is a bouncing ball animation where the animator sets the keyframes at the apex of the ball’s bounce and the moment when it hits the ground, then lets the software generate all the in-between frames. This makes it a lot more efficient and time-saving to create smooth and consistent motion. 

There are 3 basic types of tweening:

• Classic/Linear – the subject will move at a constant speed and direction between keyframes, resulting in a straight-line motion (e.g a bird flying across the screen).

• Motion – a more advanced and versatile form of tweening that introduces more dynamic movements by allowing the animator to create curved or circular motion paths. Additionally, the scale, rotation and colour of the subject can also be changed using motion tweeting.

Image: Classic vs. Motion Tweening, Image by Adobe (https://helpx.adobe.com/au/animate/using/differences-between-motion-and-classic-tweens.html) 

• Shape – morphs one shape into another by interpolating the in-between shapes. The animator can also customise what the intermediate shapes will look like by instructing the software which points on the initial shape correspond to specific points on the final shape.  

Image: Shape Tweening, Image by Adobe (https://helpx.adobe.com/in/animate/using/Tweens.html) 

Buttons

Buttons are interactive symbols in an animation used to trigger an action (e.g. play/pause, volume, navigation). Each button contains four distinctly labelled frames that represent the four different states:

• Up – the default state of the button when it has not been clicked and the pointer is not hovering over it 

• Over – when it is hovered over (aka rollover)

• Down – when it is actually clicked

• Hit – represents the click area where the button is clickable (usually used for small interactive text that is not encompassed within a larger shape, otherwise the action will only be triggered if the mouse clicks exactly on one of the strokes of a letter).

Image: Clickable Area, Image by Ahmad Shadeed (https://ishadeed.com/article/clickable-area/)

Video: Animate – Creating Buttons, Video by professorjedi (https://www.youtube.com/watch?v=Z83xTtYjN3U)