Contract for the Distributed App, EtherCanvas
This contract extends from the OpenZeppelin ERC721 (NFT) contract. It also contains logic to implement EIP-2309. This makes the minting process much cheaper. This logic is contained within ERC2309.
The main thing this contract can do, in addition to the standard NFT functionality, is set the users artwork and keep track of it on chain.
This is accomplished by calling setColorBytes which in turn emits the ColorBytesUpdated event. By using an event a lot of gas is saved, making
updating the image more economical. This function is available only to the NFT owner.
If you want to know more about how this contract is used, please visit EtherCanvas.