This is the smart contract that powers the backend logic of Ethereum Pixels, an interactive 1000x1000 grid that allows Ethereum users to own and maintain Pixels. It runs on the main Ethereum blockchain and was partly inspired by Reddit's r/place.
- Mapping of one million Pixels containing ownership, price and color information
- Mapping of Ethereum addresses to stored balance and a personalized message that is displayed on all Pixels owned by the address
- Any Ethereum account may purchase Pixels by interacting with the API
- Current owner of a Pixel is paid when the Pixel is purchased by another account
- Stored balance and payments using the withdrawal pattern
- Automatic refunds on a failed purchase due to invalid coordinates or unmet price
- Automatic price increment logic when a Pixel changes ownership
- Small maintenance fee levied for each successful purchase
The Pixel colors are stored as 24-bit unsigned integers that mostly correspond to a typical web color palette. For example, #ff0000 (red) is stored as 16711680. The only exception is that 0, which is also the value returned by Solidity for uninitialized memory, is rendered on the front end as transparent instead of #000000 (black).
buyPixel(uint16 row, uint16 col, uint24 newColor)getPixelColor(uint16 row, uint16 col)getPixelPrice(uint16 row, uint16 col)checkPendingWithdrawal()withdraw()