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How We Built r/Place

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Re: How We Built r/Place

#221

Post by subkamran »

madlee wrote: post #117
subkamran wrote: post #99

This is awesome but man, reading the canvas portion was a bit distressing. I wonder why they didn't use a game engine to do this? All the work they did has been implemented already in several JS game engines, such as the one I help maintain (it's free and OSS), https://excaliburjs.com . We support all the features they needed including mobile & touch support. They could have also used Phaser ( http://phaser.io ) too…

Hi, I wrote the majority of that part of the project (canvas stuff) & that section of the article – the simple answer is that I have a lot of experience working with the canvas API directly, but little to no experience using any of the popular JS game engines out there (I played around with Phaser years ago, but not very much). I don't think it would've saved me any time to be honest.

That's totally fair, I get the sentiment. Great job nonetheless!

Re: How We Built r/Place

#222

Post by soup10 »

nojvek wrote: post #185
soup10 wrote: post #175

Earlier quoted context omitted.

To me it seems a little over-engineered but it held up so props to them.

Why do you think it's over engineered. The scaling issues made sense. Cdn was a great move to limit throughput of requests. Redis made sense, javascript canvas and typedarrays made sense. How else would you have done it?

For the core application of writing pixels to the board, I would of used a more efficient monolithic design with less points of failure. One big server could handle 333 pixels/s(their expected volume). Not sure that using cassandra and redis is really necessary or makes things easier.

The secondary goal of pushing pixel updates to lots of users would probably want separate hardware. I would probably fake it so its not really realtime. If you send the web client batches of updates to replay on the board it looks realtime and doesn't require persistent connections.

Re: How We Built r/Place

#223

Post by [deleted] »

ag_47 wrote: post #28

Now I'm curious, Are there any websites that do something similar to /r/place? (hackathon idea?) Also, reminds be of the million dollar front page [1]. [1] https://en.wikipedia.org/wiki/The_Million_Dollar_Homepage

[deleted]

Re: How We Built r/Place

#224

Post by Ajedi32 »

77pt77 wrote: post #164
justintbassett wrote: post #69

Earlier quoted context omitted.

my fault :). I have to get a few things ready for a public release of more data

Is this data: https://www.reddit.com/r/place/comments/6396u5/rplace_archiv... Complete? I've been working with that.

That data was recorded by the community. It took everyone a while to figure out how to grab a snapshot of the canvas though, so a few hours of data near the start are missing.

Re: How We Built r/Place

#225

Post by thinkmoore »

mozumder wrote: post #2

> We actually had a race condition here that allowed users to place multiple tiles at once. There was no locking around the steps 1-3 so simultaneous tile draw attempts could all pass the check at step 1 and then draw multiple tiles at step 2. This is why you use a proper database. I'd probably add a Postgres table to record all user activity, and use that to lock out users for 5 minutes as an initial filter. Have tr…

Database choice aside, I'm shocked that this wasn't noticed when designing the app... It's clearly not a design decision because they refer to it as an error later in the paragraph.

Re: How We Built r/Place

#226

Post by a_bonobo »

Weird question - why does that bash script use absolute paths for standard tools like awk and grep (/usr/bin/awk instead of just awk)? Is this some best practice I know nothing about?

Re: How We Built r/Place

#227

Post by travmatt »

easytiger wrote: post #212
wishinghand wrote: post #209

Earlier quoted context omitted.

> the too-common comments on Reddit and HN where people claim that they could rebuild FB or Uber as a side project. I'm pretty active on both. What threads/subreddits are you reading?

you should try r/unitedkingdom where all posters are pretty sure they could flawlessly redesign modern civilization

To be fair that's kinda the history of the United Kingdom.

Re: How We Built r/Place

#228

Post by developer2 »

josephg wrote: post #194
firebones wrote: post #190

Earlier quoted context omitted.

I wish I had enough spare cash to take you up on a bet that you could implement this in less than a weekend. Maybe HN can crowdfund paying you for two days at $1000/day to replicate, versus your time and a $3000 rebate if you can't.

My loved ones are out of town, so you're on! I'll do it for the fun of it and the experience. And because I still haven't built anything on top of kafka, but there's no time like now to fix that. The challenge is: Meet the main requirements of r/place: 1000x1000 image, a web based editor, 333+ edits / second, with an architecture that can scale to 100k simultaneous users (although that part will be hard to actually t…

>> I won't implement mobile support

Mobile support was a huge factor for /r/place. To reimplement the project while completely ignoring mobile is basically taking out maybe 30% of the effort required. It's a bit of a copout to claim "can implement in a weekend", while discounting one of the main reasons why it is nearly impossible to hammer out solo in a single weekend.

The other "big ticket item" is integrating such a system into an existing live stack. It's very convenient that you get to pick the tools you think are most efficient for the job from scratch; it's quite another to restrict yourself to an existing set of tech.

>> an architecture that can scale to 100k simultaneous users (although that part will be hard to actually test)

Also this. Reddit had a single opportunity to deploy live. You can't throw out many days of required dev/staging benchmarking for a system that must work on first deploy. You're not "done" after a weekend unless your first deploy both works 100% and scales as required.

tldr; Were I to do what you are doing, it would be out of interest and to put it live for others to use. What seems disingenuous is to do so with the primary goal of proving that "see, child's play - it's not difficult at all!". The goal should be to build something that works, not to rush the job as some way to show off and take something away from Reddit's efforts.

Re: How We Built r/Place

#229

Post by Ajedi32 »

wishinghand wrote: post #209
ChicagoBoy11 wrote: post #124

I love write-ups like this because they are such a nice contrast to the too-common comments on Reddit and HN where people claim that they could rebuild FB or Uber as a side project. Something as superficially trivial as the r/Place requires a tremendous amount of effort to run smoothly and there are countless gotchas and issues that you'd never even begin to consider unless you really tried to implement it yourself.…

> the too-common comments on Reddit and HN where people claim that they could rebuild FB or Uber as a side project. I'm pretty active on both. What threads/subreddits are you reading?

Here's one: https://www.reddit.com/r/programming/comments/656z8t/how_we_...

Pretty funny considering the content of the post he wrote that on.

Re: How We Built r/Place

#230

Post by conradfr »

ChicagoBoy11 wrote: post #124

I love write-ups like this because they are such a nice contrast to the too-common comments on Reddit and HN where people claim that they could rebuild FB or Uber as a side project. Something as superficially trivial as the r/Place requires a tremendous amount of effort to run smoothly and there are countless gotchas and issues that you'd never even begin to consider unless you really tried to implement it yourself.…

With a polished front-end maybe not in a week-end but I was thinking that it was a good use case for a fun Elixir/Phoenix exercise anyway.
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