8 ms·

Show HN: Ethereum Canvas – Draw on the blockchain

69 points by fragosti 9y ago

guywaffle 9y ago
Why?
- fragosti 9y ago
  Just as an experiment. Wanted to see what it was like to write a smart contract. Example I chose is a bit contrived I agree.
- josiahtu 9y ago
  No need to be so cynical.
  - guywaffle 9y ago
    I don’t see what’s so cynical? There are a bunch of pointless Ethereum contracts made to get Ethers quick and free. This and crypto.love are dumb as hell and shouldn’t be posted on here
    - googletazer 9y ago
      Then build something better instead of shitting on others
      - guywaffle 9y ago
        That makes no sense. I am saying this is a scam to get Ether quick and cheap. There is no need to put a drawing or a love note on a blockchain, and me making something better won’t stop people from getting scammed by stuff like this.
sharemywin 9y ago
Couldn't get the drawing part to work. do you need metamask or mist?
- mrguyorama 9y ago
  I get an "invalid JsonRPC" error, working in neither firefox nightly or chrome, on mac OSX
noxToken 9y ago
Does not work for me - even with blockers disabled: Control.js:111 Uncaught TypeError: Cannot read property 'map' of null at t.n.optionsToShow (Control.js:111) at t.value (Control.js:233) at f._renderValidatedComponentWithoutOwnerOrContext (ReactCompositeComponent.js:796) at f._renderValidatedComponent (ReactCompositeComponent.js:819) at f._updateRenderedComponent (ReactCompositeComponent.js:743) at f._performComponentUpdate (ReactCompositeComponent.js:721) at f.updateComponent (ReactCompositeComponent.js:642) at f.receiveComponent (ReactCompositeComponent.js:544) at Object.receiveComponent (ReactReconciler.js:122) at f._updateRenderedComponent (ReactCompositeComponent.js:751) getContract.js:19 Error: Invalid JSON RPC response: "" at Object.InvalidResponse (errors.js:35) at XMLHttpRequest.r.onreadystatechange (httpprovider.js:111) VM146:1 OPTIONS http://localhost:8545/ net::ERR_CONNECTION_REFUSED Main.js:43 Uncaught (in promise) TypeError: Cannot read property 'getNumberOfShapes' of undefined at Main.js:43 at <anonymous> errors.js:35 Uncaught (in promise) Error: Invalid JSON RPC response: "" at Object.InvalidResponse (errors.js:35) at XMLHttpRequest.r.onreadystatechange (httpprovider.js:111) Edit: From the FAQ > How does this work? >You'll need the Metamask Chrome extension or an Ethereum enabled browser like Mist or Parity to get started.
_salmon 9y ago
Getting a 404 on the /faq page.
- fragosti 9y ago
  This should be fixed now :)
fragosti 9y ago
hello! submitter here. Apologize if it's buggy - did not realize this would catch on! Yes you need the metamask chrome extension. Looking into the other issues now. Thank you for all your feedback! Update: Appreciate some of you actually trying to submit transactions. The current gas price is around 7 gwei (https://ethgasstation.info/ https://ethgasstation.info/) so there is a high chance that transaction will time out if you put a gas price less than that. If that is your intention that is fine ;) Update 2: Apparently my total Gas calculation was too optimistic, which has caused some of the transactions to fail. I just made the estimation less optimistic (you get all unused gas back anyway). I hope that works and apologies to everyone who had a bad transaction.
Florin_Andrei 9y ago
There's no way a single shared blockchain would be able to serve the whole world. The number of transactions per second is one thing. The size of the chain is another. If we all start throwing money transactions AND idle drawings into the same bucket, it will overflow. Something needs to change. The current architecture clearly does not scale. Maybe something more like Pascal Coin would be better able to scale up to become used worldwide for daily transactions. EDIT: Before you downvote, I'd like to ask you a few questions. Are you invested in ETH or some other blockchain technology? And if you are, how does that color your thought process?
- DalasNoin 9y ago
  Have a look into blockchain sharding. There is also Lightning and Plasma, though they are far less promising.
  - kordlessagain 9y ago
    What is your rationalization for saying Lightning is not promising? I think that, given the state of the ecosystem, spreading opinion around as fact is not healthy.
    - 0wing 9y ago
      It sounds like Lightning is attempting to solve an unsolvable NP-hard math problem regarding routing. [1] The Lightening network is mostly a gimmick attempt to save the design failures of scaling from the BTC communities refusal to increase network bandwidth in order to save disk space. That and for the Lightening network to work without opening up a dozen "deposit channels" into everywhere you shop, users will be pushed into larger liquidity hubs, i.e. payment processor middlemen which is ironic given this is exactly what Satoshi's white paper sought to avoid. [1] https://en.wikipedia.org/wiki/Travelling_salesman_problem https://en.wikipedia.org/wiki/Travelling_salesman_problem
      - rspeer 9y ago
        I am not a bitcoin fan but I can't imagine anything like this would be affected by the NP-hardness of the traveling salesman problem. It's not like the system breaks if someone finds a way that a payment could have been routed faster. There are quick approximations to the TSP. Also, a payment network doesn't sound like a single object that has to traverse a graph with various costs, it sounds like a network flow problem.
eosrei 9y ago
https://steempixels.com https://steempixels.com is a free-to-use (or optionally pay) example of pixel drawing on the Steem blockchain.
IncRnd 9y ago
Does Ethereum play Crysis?
- nnash 9y ago
  Yes but you need to pay each time you press "W".
fivedogit 9y ago
I built something like this 2 years ago. And it's 3D! http://etheria.world http://etheria.world
- markhall 9y ago
  Would be interested in hearing if/when you received attention to it and how ETH prices affected users willingness to spend 1+ETH to play/us. Any future plans to keep it going and add to it?
  - fivedogit 9y ago
    I think a few dozen tiles were purchased at 1 ETH when it was about a dollar per ETH. People seemed to like it although it was challenging to build things. I can see in the contract data that some people bought tiles, mined blocks, but didn't understand how to place the blocks on the tiles, so the blocks remain hidden. Anyway yeah I'm thinking of resurrecting it soon. I've kept an entrepreneurial/techie ear open since I built it and I think I finally know what I want to do to bring it back to life. As far as ownership, I'll probably just buy all the remaining tiles myself (the money goes to me anyway) and then sell at more reasonable prices on the secondary market.
deleted 9y ago
[deleted]
hellbanner 9y ago
Your page is hitting http://localhost:8545/ http://localhost:8545/ .
chimen 9y ago
Reminds me of the million dollar homepage of 10 years ago: http://www.milliondollarhomepage.com/ http://www.milliondollarhomepage.com/
AncoraImparo 9y ago
Doesn't actually work though.
- fragosti 9y ago
  It works - but people have been trying to submit a transaction with too little gas or too low of a gas price.
myth_drannon 9y ago
There is also a course how to build something similar https://www.newline.co/courses/million-ether-homepage https://www.newline.co/courses/million-ether-homepage

69 points by fragosti 9y ago

guywaffle 9y ago

Why?

fragosti 9y ago
Just as an experiment. Wanted to see what it was like to write a smart contract. Example I chose is a bit contrived I agree.
josiahtu 9y ago
No need to be so cynical.
- guywaffle 9y ago
  I don’t see what’s so cynical? There are a bunch of pointless Ethereum contracts made to get Ethers quick and free. This and crypto.love are dumb as hell and shouldn’t be posted on here
  - googletazer 9y ago
    Then build something better instead of shitting on others
    - guywaffle 9y ago
      That makes no sense. I am saying this is a scam to get Ether quick and cheap. There is no need to put a drawing or a love note on a blockchain, and me making something better won’t stop people from getting scammed by stuff like this.

sharemywin 9y ago

Couldn't get the drawing part to work. do you need metamask or mist?

mrguyorama 9y ago
I get an "invalid JsonRPC" error, working in neither firefox nightly or chrome, on mac OSX

noxToken 9y ago

Does not work for me - even with blockers disabled: Control.js:111 Uncaught TypeError: Cannot read property 'map' of null at t.n.optionsToShow (Control.js:111) at t.value (Control.js:233) at f._renderValidatedComponentWithoutOwnerOrContext (ReactCompositeComponent.js:796) at f._renderValidatedComponent (ReactCompositeComponent.js:819) at f._updateRenderedComponent (ReactCompositeComponent.js:743) at f._performComponentUpdate (ReactCompositeComponent.js:721) at f.updateComponent (ReactCompositeComponent.js:642) at f.receiveComponent (ReactCompositeComponent.js:544) at Object.receiveComponent (ReactReconciler.js:122) at f._updateRenderedComponent (ReactCompositeComponent.js:751) getContract.js:19 Error: Invalid JSON RPC response: "" at Object.InvalidResponse (errors.js:35) at XMLHttpRequest.r.onreadystatechange (httpprovider.js:111) VM146:1 OPTIONS http://localhost:8545/ net::ERR_CONNECTION_REFUSED Main.js:43 Uncaught (in promise) TypeError: Cannot read property 'getNumberOfShapes' of undefined at Main.js:43 at <anonymous> errors.js:35 Uncaught (in promise) Error: Invalid JSON RPC response: "" at Object.InvalidResponse (errors.js:35) at XMLHttpRequest.r.onreadystatechange (httpprovider.js:111) Edit: From the FAQ > How does this work? >You'll need the Metamask Chrome extension or an Ethereum enabled browser like Mist or Parity to get started.

_salmon 9y ago

Getting a 404 on the /faq page.

fragosti 9y ago
This should be fixed now :)

fragosti 9y ago

hello! submitter here. Apologize if it's buggy - did not realize this would catch on! Yes you need the metamask chrome extension. Looking into the other issues now. Thank you for all your feedback! Update: Appreciate some of you actually trying to submit transactions. The current gas price is around 7 gwei (https://ethgasstation.info/ https://ethgasstation.info/) so there is a high chance that transaction will time out if you put a gas price less than that. If that is your intention that is fine ;) Update 2: Apparently my total Gas calculation was too optimistic, which has caused some of the transactions to fail. I just made the estimation less optimistic (you get all unused gas back anyway). I hope that works and apologies to everyone who had a bad transaction.

Florin_Andrei 9y ago

There's no way a single shared blockchain would be able to serve the whole world. The number of transactions per second is one thing. The size of the chain is another. If we all start throwing money transactions AND idle drawings into the same bucket, it will overflow. Something needs to change. The current architecture clearly does not scale. Maybe something more like Pascal Coin would be better able to scale up to become used worldwide for daily transactions. EDIT: Before you downvote, I'd like to ask you a few questions. Are you invested in ETH or some other blockchain technology? And if you are, how does that color your thought process?

DalasNoin 9y ago
Have a look into blockchain sharding. There is also Lightning and Plasma, though they are far less promising.
- kordlessagain 9y ago
  What is your rationalization for saying Lightning is not promising? I think that, given the state of the ecosystem, spreading opinion around as fact is not healthy.
  - 0wing 9y ago
    It sounds like Lightning is attempting to solve an unsolvable NP-hard math problem regarding routing. [1] The Lightening network is mostly a gimmick attempt to save the design failures of scaling from the BTC communities refusal to increase network bandwidth in order to save disk space. That and for the Lightening network to work without opening up a dozen "deposit channels" into everywhere you shop, users will be pushed into larger liquidity hubs, i.e. payment processor middlemen which is ironic given this is exactly what Satoshi's white paper sought to avoid. [1] https://en.wikipedia.org/wiki/Travelling_salesman_problem https://en.wikipedia.org/wiki/Travelling_salesman_problem
    - rspeer 9y ago
      I am not a bitcoin fan but I can't imagine anything like this would be affected by the NP-hardness of the traveling salesman problem. It's not like the system breaks if someone finds a way that a payment could have been routed faster. There are quick approximations to the TSP. Also, a payment network doesn't sound like a single object that has to traverse a graph with various costs, it sounds like a network flow problem.

eosrei 9y ago

https://steempixels.com https://steempixels.com is a free-to-use (or optionally pay) example of pixel drawing on the Steem blockchain.

IncRnd 9y ago

Does Ethereum play Crysis?

nnash 9y ago
Yes but you need to pay each time you press "W".

fivedogit 9y ago

I built something like this 2 years ago. And it's 3D! http://etheria.world http://etheria.world

markhall 9y ago
Would be interested in hearing if/when you received attention to it and how ETH prices affected users willingness to spend 1+ETH to play/us. Any future plans to keep it going and add to it?
- fivedogit 9y ago
  I think a few dozen tiles were purchased at 1 ETH when it was about a dollar per ETH. People seemed to like it although it was challenging to build things. I can see in the contract data that some people bought tiles, mined blocks, but didn't understand how to place the blocks on the tiles, so the blocks remain hidden. Anyway yeah I'm thinking of resurrecting it soon. I've kept an entrepreneurial/techie ear open since I built it and I think I finally know what I want to do to bring it back to life. As far as ownership, I'll probably just buy all the remaining tiles myself (the money goes to me anyway) and then sell at more reasonable prices on the secondary market.

deleted 9y ago

[deleted]

hellbanner 9y ago

Your page is hitting http://localhost:8545/ http://localhost:8545/ .

chimen 9y ago

Reminds me of the million dollar homepage of 10 years ago: http://www.milliondollarhomepage.com/ http://www.milliondollarhomepage.com/

AncoraImparo 9y ago

Doesn't actually work though.

fragosti 9y ago
It works - but people have been trying to submit a transaction with too little gas or too low of a gas price.

myth_drannon 9y ago

There is also a course how to build something similar https://www.newline.co/courses/million-ether-homepage https://www.newline.co/courses/million-ether-homepage