Show HN: /r/place backed by the Bitcoin blockchain

Post by root_axis » Mon, May 01, 2017, 2:09 PM UTC

Post by iplaw » Mon, May 01, 2017, 2:21 PM UTC

root_axis wrote: post #2

I tend to be pretty skeptical of all things crypto, but this seems pretty cool. It's not very useful, but it seems like a fun concept.

Post by i_cant_speel » Mon, May 01, 2017, 2:25 PM UTC

pavel_lishin wrote: post #3

A fun way to get people to donate money to wallets you control. Kind of like Million Dollar Homepage, but without any pesky guarantees.

Post by scientaster » Mon, May 01, 2017, 2:32 PM UTC

  contract Place {
    struct Pixel {
      bytes3 color;
      uint lastPayment;
    }

    Pixel[10000][10000] board;

    modifier onBoard(uint x, uint y) {
      if (x > 10000 || y > 10000) {
        throw;
      } 
      _;
    }

    // Accepts funds, if the funds sent are greater than funds for that pixel last, change the color.
    function colorPixel(uint x, uint y, bytes3 color) payable onBoard(x, y) { 
      Pixel p = board[x][y];
      if (msg.value > p.lastPayment) {
        msg.sender.send(p.lastPayment); // refund previous price of pixel
        p.color = color;                // set the color
        p.lastPayment = msg.value;      // set new cost to whatever the person sent in
      } else {
        throw;
      }
    }
  }

Post by mess110 » Mon, May 01, 2017, 2:33 PM UTC

scientaster wrote: post #8

Would have been much easier with an ethereum smart contract. No gimmicky address list, it's a crowdsourced picture in the blockchain. contract Place { struct Pixel { bytes3 color; uint lastPayment; } Pixel[10000][10000] board; modifier onBoard(uint x, uint y) { if (x > 10000 || y > 10000) { throw; } _; } // Accepts funds, if the funds sent are greater than funds for that pixel last, change the color. function colorPi…