How To Highlight, Hide And Fade Parts.

Highlighting

Single or multiple parts can be highlighted for the viewer by toggling the bulb icon on/off against each part

Opacity

Opacity is stored against a keyframe. If you add a keyframe at 0 seconds, set the opacity to 50%, it will stay at 50% opacity during that step. If you were to add a keyframe at 3 seconds and set the opacity to 100%, over the 3 seconds, it will animate the opacity from 50 to 100%.

Hiding

Single or multiple parts can be hidden using the hide icon against each part; if a part is hidden, it will not be displayed during the step.