I added borders to stockpile mock-ups for SteamDF over a year ago. XD
Edit: haha! Fluid roller animation with a single chain. I'm finally happy with the result.
The chain and mechanism looks good. There's still a bit that I consider short of perfect, though. This would require extra work from Toady, but it would look a lot better if adjacent cases didn't have those brown things. Perhaps not worth Toady's time just for this one case, but a more diverse and powerful system of conditional adjacency graphics would be very useful in general. Barring that, it might be good to reimagine that connection so it's at least not as obtrusive; they look a bit much (particularly with regards to implicit height) even when it's just one by itself.
Almost happy with the chains
I'd suggest one roller in each end rather than a single one in the middle (with power distribution from the center of the side), as that would tie in with the underlying conveyor belt logic, and also the possible misinterpretation of a giant cog in an axle.
Is conveyer belt logic actually what underlies it? I'm pretty sure the rollercoaster-like design is still the most likely, so a single roller is appropriate. Plus, one at each end would tile poorly.
Finally: I don't envy you artists, having to balance diametrically opposed comments from everyone and their dog.
That's a pretty rare case, though. Most of these have way more than two suggestions going on. And it's not like they have to listen to anybody, so it's only a resource to make the quality better. Fortunately, both of the people are long-time modders who very evidently care about the quality of the final product.
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