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How Drawpile works

colesantiago 2021-08-17 19:42:06 +0000 UTC [ - ]

Interesting that there isn't any mention or use of CRDTs, that would have been the first thing to see from this document.

Nevertheless, it is still refreshing to see a different way of doing things like collaborative drawing without them.

Curious to know of this design decision.

zffr 2021-08-17 21:06:27 +0000 UTC [ - ]

> Drawpile solves the second problem in the most simple way possible: all edits go through a central server, which distributes them to all connected clients (including the originator) in the same order. So, when a client receives commands from the server, it knows all the other clients also received, or will receive, them in the same order.

You don't need CRDTs if you have a centralized server and require clients to be connected to make edits. CRDTs are useful when you want to enable collaboration in a decentralized way.

colesantiago 2021-08-17 21:38:34 +0000 UTC [ - ]

So does this mean Figma is decentralized since they are also using CRDTs?

nh2 2021-08-17 22:02:18 +0000 UTC [ - ]

"You don't need X for centralised" does not imply "if you have X then you're decentralised".

Beyond that simple logic: https://www.figma.com/blog/how-figmas-multiplayer-technology...

> Figma isn't using true CRDTs though. CRDTs are designed for decentralized systems where there is no single central authority to decide what the final state should be. There is some unavoidable performance and memory overhead with doing this. Since Figma is centralized (our server is the central authority), we can simplify our system

colesantiago 2021-08-17 22:52:18 +0000 UTC [ - ]

Interesting, so this must mean that Figma must be using CRDTs wrong then, but it works for them anyway since they aren't using "true CRDTs".

pc86 2021-08-17 23:57:30 +0000 UTC [ - ]

Maybe CRDTs (or more precisely, their implementation of them) give them some other benefit beyond the disregarded ability to be decentralized. It doesn't necessarily mean they're using them incorrectly.

sambroner 2021-08-17 19:36:26 +0000 UTC [ - ]

Would be really neat to put Drawpile on the Fluid Framework. You could easily map Drawpile's ordered operations into distributed data structures. I did a similar thing a few months ago with QuillJS's operations and it worked great!

The main advantage of that integration would be a ready made Azure service + future integration with Microsoft Office.

(I used to work on the Fluid Framework)

dang 2021-08-17 20:30:56 +0000 UTC [ - ]

Only one small past related thread:

Drawpile is a free software collaborative drawing program - https://news.ycombinator.com/item?id=17141368 - May 2018 (4 comments)

2021-08-17 22:36:05 +0000 UTC [ - ]