I think you are confusing me or I am.
you were suggesting layiing another element over the artwork.
Although it could be accepted as Masking, it is technically fairly different from MASKING in the way we do when making graphical design , isn't it?
it's more like Layer Clipping in Photoshop.
Clipping is also somewhat similar to Masking, but there are limitations.
Half tranceparency should be involved in Masking as well as changing the shape of Mask.
I tried this before posting this question: http://forums.tumult.com/t/masking-elements-by-using-content-overflow-groups/1342
but it cannot be doen in Hype when i try to reveal it from the bottom to top OR little more coplecated animating - for example, grouping other two groups and animating them each way.
Because Hype also animate their origins as well.
And an Undo makes the whole layout scattered which is frustrating.
speaking of masking, I would not have done cutting the artwork piece by piece if the shape of Mask could be animated.
Retangular shaped clipping were an alternative way in the first place for me.
I said 'basic property' because i thought CSS clipping property is done only in ractangular shape- mush simpler than a bezier path or mask. I could be wrong.
anyway, I made more videos quickly.
the yellow ribbons consist of 5 pieces and each piece is animated by clipping in a retangular shape.
I did the samy approch to the roads.
I also simply applied Easing.
No coding involved at all.
The whole animation going to be much longer in my project.
since now it is clear Hype does not support animating Clipping property, I think It would be a fair Feature Request I think.