Whiteboard Animations with Grease Pencil and Build Modifier

Currently we almost can create great teaching and presentation experiences thanks to the Grease Pencil and its Build Modifier, the only things pending I think are: a way to attach an object (either 2d, or 3d), and walk it through the whole build animation, like a hand or pencil drawing the sketches. And something else needed is that native shapes like lines, rectangles, circles, and eventually if they add Text objects, draw correctly with the Build modifier and not just show up immediately.

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