A brief overview of animations
Today’s game character animations are completely different from the 2D animations from cartoons created about 100 years ago, such as the famous cartoons by Walt Disney in the 1930s. But there are still a lot of similarities between modern computer animations and the hand-drawn animations of the past.
glTF animations are based on key poses. Every animation has at least a starting and an ending key pose, and most animations also have many key poses at specific points in time. If the starting and the ending key poses are the same, or similar, the animation can be played in a continuous loop. But if these two key poses are too different, another animation must follow at the end, or the direction of the animation must be reversed.
To fill the time between the key poses, intermediate frames are calculated. While intermediate frames had to be drawn by hand in the past, the calculations in modern 3D animations are done by interpolating the vertex...
