Up to 10 products
This fragmentation hurts portability. Code that performs well on one runtime may behave differently (or poorly) on another, even though it's using "standard" APIs. The complexity burden on runtime implementers is substantial, and the subtle behavioral differences create friction for developers trying to write cross-runtime code, particularly those maintaining frameworks that must be able to run efficiently across many runtime environments.
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Interaction — Draggable, Hoverable, Clickable mobjects
Rendering a character as a lower block and then as an upper block gives you two “frames” of motion within the same character and looks much smoother.