In this repository, you will find the source code of the Multiavatar generator rewritten in Solidity, the Ethereum programming language for writing smart contracts.
Multiavatar in Solidity is the essential part of the upcoming Multiavatar NFT collection, as all NFT images of the collection will be generated by this smart contract entirely on-chain, eliminating the need for a centralized server to host the Multiavatar generator.
This smart contract is currently deployed on the Ethereum Goerli testnet here: 0x67da528aD7DabF168c6fdD99aFb47028A86317F0
You can test the contract by generating on-chain avatars. Simply query the multiavatar function on Etherscan, providing an avatar name as the first parameter, and 0 as the second parameter. Generating avatars on-chain doesn't incur a transaction fee.
Testnet example of the Satoshi NFT on OpenSea. The NFT image is generated by this smart contract.
When deployed on the mainnet, the Multiavatar in Solidity smart contract will become a part of the Ethereum network and will empower the Multiavatar NFT collection with the ability to generate 12,230,590,464 cryptographically unique avatars. The on-chain approach will guarantee Multiavatar NFT collection's reliable accessibility for the long term, as it doesn't depend on any third parties and will exist as long as Ethereum does.
The Solidity programming language and its development environment are very different from JavaScript, PHP, or Python, in which Multiavatar was previously implemented. That is why significant portions of the Multiavatar code in Solidity needed to be rewritten in completely different ways.
While the Multiavatar generator is designed to be lightweight (69 KB) in a web environment, due to the limited space available on the Ethereum blockchain, the resulting smart contract is very large in Ethereum terms. Although the combined size of source materials (SVG image shapes and color themes) is only around 60 KB in plain text, they need to be presented as string arrays in the Solidity code in order to be looped through during an avatar generation. This inclusion of string arrays in the contract makes it expensive to deploy. Additionally, the contract needs to be divided into separate contracts that inject themes and SVG shapes data into the main contract, as the full contract would otherwise exceed the size limits imposed by the Ethereum blockchain.
Because the smart contract is relatively large, the deployment is complex and the cost is high. With gas price at 10 Gwei, the fee for deploying the contract is around 1.5 ETH. There may still be opportunities to further optimize the contract and reduce the deployment cost. Your ideas for contract optimization are welcome.
On a live blockchain, such as the Ethereum Goerli testnet, the contract needs to be divided into separate contracts and deployed in separate transactions because of the contract size and transaction size limits implemented by the blockchain. This is the currently preferred method for deployment, using the deploy_ALL.js script and Solidity files located in the contracts folder.
On a local Hardhat environment, the contract can also be deployed from a single Solidity file. The whole contract in a single file can be found in contracts_single folder. If you want to work with a contract in a single file, rename your contracts_single folder to contracts, and then use the deploy.js script.
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Clone this repository and run
npm install -
For local deployment, first start a Hardhad node by running
npx hardhat node -
To deploy the contract on localhost, open a new terminal window and run the following command:
npx hardhat run scripts/deployAll.js --network localhost -
To deploy on the Ethereum Goerli testnet, first rename
.env.examplefile to.envand update it with your keys, and then run:
npx hardhat run scripts/deployAll.js --network goerli
If you have deployed the contract on your local Hardhat blockchain, you can interact with the contract through the Hardhat console:
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First open a new terminal window and run the following command to open the console:
npx hardhat console --network localhost -
Now run the following commands in the console to connect to your contract deployed at the default local address:
const MNFT = await ethers.getContractFactory('MNFT')
const mnft = await MNFT.attach('0x5FbDB2315678afecb367f032d93F642f64180aa3') -
To get only the avatar SVG code without traits, run the following command:
await mnft.multiavatar("Satoshi", false) -
To get the Base64 encoded avatar SVG code with traits for the metadata API, run:
await mnft.multiavatar("Satoshi", true) -
Commands for testing the injected SVG code and themes:
await mnft.getThemes('00','A','env')
await mnft.getParts('00', 'env') -
Lock the contract after injecting all SVG code and themes:
await mnft.lockGen() -
To test the 'Satoshi' avatar, in your terminal run:
npx hardhat test
Code review, feedback, and optimization ideas are welcome.
Report issues in the issue tracker.
Feel free to make a pull request or suggest ideas.
To prevent fake Multiavatar NFTs before the official collection launch, the Multiavatar in Solidity smart contract source code is currently released under a proprietary license that permits usage solely for personal and non-commercial purposes.
After the official Multiavatar NFT release, the license of the source code will switch to MIT, and for the Multiavatar graphic assets, the CC0 license will be applied. These licenses will provide the maximum flexibility and freedom for users and developers to build upon and utilize the Multiavatar project. It will allow for the project to spread and be used widely, encouraging creativity and innovation.
For additional information on how the Multiavatar generator works, please refer to the Multiavatar in JavaScript repository.
To learn more about the NFT collection, visit the Multiavatar NFT website.
