@orao-network/zkvrf v0.2.3

ORAO zkVRF SDK

ORAO's Zero-Knowledge Verifiable Random Function provides fast and unbiased randomness on most EVM networks. zkVRF is currently deployed to Polygon Amoy Testnet at 0x3Bc8ce8a86eeC25AE77Af96ae06b0e605Fb93d52 and verifier at 0xA8d4892a93c0e1cE66754823306f16809BE0F26D

Features

• ability to pre-pay for VRF requests (on-chain treasury per wallet)
• callback option
• gas setting for faster tx

Integration example

We've built a simple Solidity contract which mints an NFT with Random features. The source code is available here

Compile and deploy:

cd examples/sol
npm run compile
npm run deploy

Solidity example:

contract OraoVRFConsumer is OraoVRFConsumerBase {
  bytes32 public seed;
  bytes32 public part1;
  bytes32 public part2;
  IOraoVRF internal _vrfCoordinator;

  constructor(address vrfCoordinator) OraoVRFConsumerBase(vrfCoordinator) {
    _vrfCoordinator = IOraoVRF(vrfCoordinator);
  }

  function fulfillRandomness(bytes32 _seed, bytes32 _part1, bytes32 _part2) internal override {
    seed = _seed;
    part1 = _part1;
    part2 = _part2;
  }

  function request(bytes32 _seed) public payable override {
    seed = _seed;
    super.request(_seed);
  }
}