Creating a three-frame animation clip to make a platform continually animate

In this recipe, we'll make a wooden-looking platform continually animate, moving upward and downward. This can be achieved with a single three-frame Animation Clip (starting at the top, then positioned at the bottom, and finally back at the top position). Note that each frame is a static position and that we will employ the animation technique known as in-betweening to create the necessary movement:

Figure 6.30 – Example of a moving platform game