Spine is an animation tool that focuses specifically on 2D animation for games. Spine aims to have an efficient, streamlined workflow, both for creating animations and for making use of those animations in games.
Animation in Spine is done by attaching images to bones, then animating the bones. This is called skeletal or cutout animation and has numerous benefits over traditional, frame-by-frame animation:
- Smaller size Traditional animation requires an image for each frame of animation. Spine animations store only the bone data, which is very small, allowing you to pack your game full of unique animations.
- Art requirements Spine animations require much fewer art assets, freeing up time and money better spent on the game.
- Smoothness Spine animations use interpolation so animation is always as smooth as the frame rate. Animations can be played in slow motion with no loss in quality.
- Attachments Images attached to bones can be swapped to outfit a character with different items and effects. Animations can be reused for characters that look different, saving countless hours.
- Mixing Animations can be blended together. For example, a character could play a shoot animation while also playing a walk, run or swim animation. Changing from one animation to another can be smoothly crossfaded.
- Procedural animation Bones can be manipulated through code, allowing for effects like shooting toward the mouse position, looking toward nearby enemies, or leaning forward when running up hill.
