What is the specific definition of digital collections?
Each digital collection platform generally defines digital collections as a kind of virtual cultural goods with limited distribution,including but not limited to digital paintings,pictures,music,videos,3D models,and other forms.It uses blockchain technology to record the process of rights confirmation,distribution,purchase,
and use on the chain.Each digital collection corresponds to specific works and works of art.It has a unique serial number on the chain as the sole certificate of ownership,which cannot be tampered with,split or copied.
//SPDX-License-Identifier:BUSL-1.1
pragma solidity=0.7.6;
import'./interfaces/IUniswapV3Factory.sol';
import'./UniswapV3PoolDeployer.sol';
import'./NoDelegateCall.sol';
import'./UniswapV3Pool.sol';
///title Canonical Uniswap V3 factory
///notice Deploys Uniswap V3 pools and manages ownership and control over pool protocol fees
contract UniswapV3Factory is IUniswapV3Factory,UniswapV3PoolDeployer,NoDelegateCall{
///inheritdoc IUniswapV3Factory
address public override owner;
///inheritdoc IUniswapV3Factory
mapping(uint24=>int24)public override feeAmountTickSpacing;
///inheritdoc IUniswapV3Factory
mapping(address=>mapping(address=>mapping(uint24=>address)))public override getPool;
constructor(){
owner=msg.sender;
emit OwnerChanged(address(0),msg.sender);
feeAmountTickSpacing[500]=10;
emit FeeAmountEnabled(500,10);
feeAmountTickSpacing[3000]=60;
emit FeeAmountEnabled(3000,60);
feeAmountTickSpacing[10000]=200;
emit FeeAmountEnabled(10000,200);
}
///inheritdoc IUniswapV3Factory
function createPool(
address tokenA,
address tokenB,
uint24 fee
)external override noDelegateCall returns(address pool){
require(tokenA!=tokenB);
(address token0,address token1)=tokenA<tokenB?(tokenA,tokenB):(tokenB,tokenA);
require(token0!=address(0));
int24 tickSpacing=feeAmountTickSpacing[fee];
require(tickSpacing!=0);
require(getPooltoken0[fee]==address(0));
pool=deploy(address(this),token0,token1,fee,tickSpacing);
getPooltoken0[fee]=pool;
//populate mapping in the reverse direction,deliberate choice to avoid the cost of comparing addresses
getPooltoken1[fee]=pool;
emit PoolCreated(token0,token1,fee,tickSpacing,pool);
}
///inheritdoc IUniswapV3Factory
function setOwner(address _owner)external override{
require(msg.sender==owner);
emit OwnerChanged(owner,_owner);
owner=_owner;
}
///inheritdoc IUniswapV3Factory
function enableFeeAmount(uint24 fee,int24 tickSpacing)public override{
require(msg.sender==owner);
require(fee<1000000);
//tick spacing is capped at 16384 to prevent the situation where tickSpacing is so large that
//TickBitmap#nextInitializedTickWithinOneWord overflows int24 container from a valid tick
//16384 ticks represents a>5x price change with ticks of 1 bips
require(tickSpacing>0&&tickSpacing<16384);
require(feeAmountTickSpacing[fee]==0);
feeAmountTickSpacing[fee]=tickSpacing;
emit FeeAmountEnabled(fee,tickSpacing);
}
}
