briq contract

The briq contract can be found at contracts/briq.cairo.
Implementation is found in the contracts/briq/ folder.

High-level overview

The briq contract should be thought of as an ERC-1155 with a slightly tweaked interface.
briqs have a material, and that material is how you'll generally talk to the contract, instead of specific token IDs. This is why briqs can be either fungible or non-fungible.

The ability to directly transfer briqs is currently partly implemented. You can only directly send briqs to another person, as there is no authorization handling.

The briq contract also contains functions to convert the fungibility of briqs, and to change their material, under contracts/briq/convert_mutate.cairo. Those functions are currently unused & can only be called by admins of the contract.

Fungible, non-fungible briq tokens & material support

To support materials efficiently, the material of a briq is embedded inside its token_id (in ERC-1155 parlance).
As a reminder, felt are [0-2^251[ (and change).
The lowest 64 bits are reserved for the material. The other 187 bits are reserved for NFT unique IDS.

Material 0 does not exist. Likewise, the briq of token_id 0 does not exist.

In practice, Fungible tokens have the same token_id as their material. Non-fungible tokens are described by 2 ^ 64 * nft_id + material.

API

In general, there are two versions of each view/external functions:

• One taking felt arguments, that end with an extra _.
• One taking Uint256 arguments, that don't.

Note that at the moment, both are felt-based, but that's expected to change (contrast the set contract).s

Balance

In general, you'll query the balance of a given material, not a given token_id as in ERC1155.
balanceOfMaterial is your regular balanceOf, but takes a material. fullBalanceOf returns the complete balance, but iterates over materials internally. Use materialsOf to query those directly.
You also have balanceOfMaterials to query several materials.
ownerOf will return the owner of a specific briq NFT token. Querying the owner of a fungible token returns 0.
balanceDetailsOfMaterial will return the full list of NFTs for a given material. You may also use tokenOfOwnerByIndex.

totalSupplyOfMaterial returns the total number of fungible & non-fungible tokens of a given material.

Minting

Fungible tokens:

mintFT takes a recipient, a material, and a quantity of token to mint.

Non-fungible tokens:

mintOneNFT takes a recipient, a material, and a unique identifier for the token.
Note that if the same briq NFT exists (same material and token id), the minting will fail.

Transfer

Transfer is implemented for owners, without approval & such for now. The set contract is always authorized to transfer briqs, which is required for minting/burning (see set contract ).

Conversion / Mutation

Those functions are intended to make NFT briqs into FT briqs and vice-versa, and to change briq material. They mostly exist in-case we discover a need for them in the future.