// SPDX-License-Identifier: MIT // OpenZeppelin Contracts (last updated v4.5.0-rc.0) (token/ERC721/extensions/ERC721Royalty.sol) pragma solidity ^0.8.0; import "../ERC721Upgradeable.sol"; import "../../common/ERC2981Upgradeable.sol"; import "../../../utils/introspection/ERC165Upgradeable.sol"; import "../../../proxy/utils/Initializable.sol"; /** * @dev Extension of ERC721 with the ERC2981 NFT Royalty Standard, a standardized way to retrieve royalty payment * information. * * Royalty information can be specified globally for all token ids via {_setDefaultRoyalty}, and/or individually for * specific token ids via {_setTokenRoyalty}. The latter takes precedence over the first. * * IMPORTANT: ERC-2981 only specifies a way to signal royalty information and does not enforce its payment. See * https://eips.ethereum.org/EIPS/eip-2981#optional-royalty-payments[Rationale] in the EIP. Marketplaces are expected to * voluntarily pay royalties together with sales, but note that this standard is not yet widely supported. * * _Available since v4.5._ */ abstract contract ERC721RoyaltyUpgradeable is Initializable, ERC2981Upgradeable, ERC721Upgradeable { function __ERC721Royalty_init() internal onlyInitializing { } function __ERC721Royalty_init_unchained() internal onlyInitializing { } /** * @dev See {IERC165-supportsInterface}. */ function supportsInterface(bytes4 interfaceId) public view virtual override(ERC721Upgradeable, ERC2981Upgradeable) returns (bool) { return super.supportsInterface(interfaceId); } /** * @dev See {ERC721-_burn}. This override additionally clears the royalty information for the token. */ function _burn(uint256 tokenId) internal virtual override { super._burn(tokenId); _resetTokenRoyalty(tokenId); } /** * This empty reserved space is put in place to allow future versions to add new * variables without shifting down storage in the inheritance chain. * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps */ uint256[50] private __gap; }