Technical Information

Deployed contracts

Mode

Base

Fantom

BSC (Deprecated)

Fantom (Deprecated, Multichain)

Interacting with the contracts

Swap

To execute a swap:

• Approve the Router contract for the token and amount you would like to swap
• Call Router.swap with parameters:
  • _path: [tokenIn, tokenOut]
  • _amountIn: amount of tokenIn to swap
  • _minOut: minimum expected output amount
  • _receiver: address of the receiver of tokenOut
• The function will revert if the amount of tokenOut sent to the receiver is less than _minOut

To get swap amounts before execution:

• Call Reader.getMaxAmountIn with parameters:
  • _vault: address of the vault
  • _tokenIn: address of token that will be given
  • _tokenOut: address of token to be received
  • The max amount of tokenIn that can be swapped will be returned
• Call Reader.getAmountOut with parameters:
  • _vault: address of the vault
  • _tokenIn: address of token that will be given
  • _tokenOut: address of token to be received
  • _amountIn: amount of tokenIn to swap
  • Two values will be returned, the first is the amount out after fees, and the second is the fee amount
  • The fee amount will be in terms of tokenOut

The Vault contract includes a usdgAmount for some calculations on tokens. This amount is updated when MLP is minted or redeemed, and during swaps based on the token's price at that time. Because of price changes, the usdgAmount may not always match the actual USD value of the tokens in the pool. To fix this, the usdgAmount is periodically updated to align with the current values.

Query Available Amounts

The maximum sum of all position sizes is limited by the amount of tokens there are in the pool and any additional caps.

To calculate the available amount of liquidity for long positions:

• indexToken: the address of the token to long
• Available amount in tokens: Vault.poolAmounts(indexToken) - Vault.reservedAmounts(indexToken)
• Available amount in USD: PositionRouter.maxGlobalLongSizes(indexToken) - Vault.guaranteedUsd(indexToken)
• The available liquidity will be the lower of these two values
• PositionRouter.maxGlobalLongSizes(indexToken) can be zero, in which case there is no additional cap, and available liquidity is based only on the available amount of tokens

To calculate the available amount of liquidity for short positions:

• indexToken: the address of the token to short
• collateralToken: the address of the stablecoin token to be used as collateral
• Available amount in tokens: Vault.poolAmounts(collateralToken) - Vault.reservedAmounts(collateralToken)
• Available amount in USD: PositionRouter.maxGlobalShortSizes(indexToken) - Vault.globalShortSizes(indexToken)
• The available liquidity will be the lower of these two values

Opening / Increasing a Position

To open or increase the size of an existing position:

• Approve the PositionRouter as a Router plugin for your account
  • Router.approvePlugin(PositionRouter address)
• Approve the Router contract for the token and amount you would deposit as collateral for the position
• Call PositionRouter.createIncreasePosition with parameters:
  • _path: [collateralToken] or [tokenIn, collateralToken] if a swap is needed
  • _indexToken: the address of the token you want to long or short
  • _amountIn: the amount of tokenIn you want to deposit as collateral
  • _minOut: the min amount of collateralToken to swap for
  • _sizeDelta: the USD value of the change in position size
  • _isLong: whether to long or short
  • _acceptablePrice: the USD value of the max (for longs) or min (for shorts) index price acceptable when executing the request
  • _executionFee: can be set to PositionRouter.minExecutionFee
  • _referralCode: referral code for affiliate rewards and rebates
  • _callbackTarget: an optional callback contract, this contract will be called on request execution or cancellation
• After this transaction is sent a keeper will execute the request, and the request will either be executed or canceled
• If the position cannot be increased for reasons such as the _acceptablePrice not being fulfillable or there being insufficient liquidity then the request will be canceled and funds will be sent back to the msg.sender that called PositionRouter.createIncreasePosition
• _minOut can be zero if no swap is required
• USD values for _sizeDelta and _price are multiplied by (10 ** 30), so for example to open a long position of size 1000 USD, the value 1000 * (10 ** 30) should be used

Closing / Decreasing a Position

To close or decrease an existing position:

• Call PositionRouter.createDecreasePosition with parameters:
  • _path: [collateralToken] or [collateralToken, tokenOut] if a swap is needed
  • _indexToken: the index token of the position
  • _collateralDelta: the amount of collateral in USD value to withdraw
  • _sizeDelta: the USD value of the change in position size
  • _isLong: whether the position is a long or short
  • _receiver: the address to receive the withdrawn tokens
  • _acceptablePrice: the USD value of the min (for longs) or max (for shorts) index price acceptable when executing the request
  • _minOut: the min output token amount
  • _executionFee: can be set to PositionRouter.minExecutionFee
  • _withdrawETH: only applicable if WFTM will be withdrawn, the WFTM will be unwrapped to FTM if this is set to true
  • _callbackTarget: an optional callback contract, this contract will be called on request execution or cancellation
• After this transaction is sent a keeper will execute the request, and the request will either be executed or canceled
• If the position cannot be decreased for reasons such as the _acceptablePrice not being fulfillable then the request will be canceled and there will be no change to the position

Positions List

A list of position details can be retrieved by calling Reader.getPositions

• _vault: the vault contract address
• _account: the account of the user
• _collateralTokens: an array of collateralTokens
• _indexTokens: an array of indexTokens
• _isLong: an array of whether the position is a long position

The returned positions will be in the order of the query, for example, given the following inputs:

• _collateralTokens: [WBTC.address, WETH.address, USDC.address]
• _indexTokens: [WBTC.address, WETH.address, WBTC.address]
• _isLong: [true, true, false]

The position details would be returned for

• Long BTC position, positionIndex: 0
• Long ETH position, positionIndex: 1
• Short BTC position, positionIndex: 2

The returned array would be a list of values ordered by the positions:

• size
  • position size in USD
  • value at: positionIndex * 9
• collateral
  • position collateral in USD
  • value at: positionIndex * 9 + 1
• averagePrice
  • average entry price of the position in USD
  • value at: positionIndex * 9 + 2
• entryFundingRate
  • a snapshot of the cumulative funding rate at the time the position was entered
  • value at: positionIndex * 9 + 3
• hasRealisedProfit
  • 1 if the position has a positive realised profit, 0 otherwise
  • value at: positionIndex * 9 + 4
• realisedPnl
  • the realised PnL for the position in USD
  • value at: positionIndex * 9 + 5
• lastIncreasedTime
  • timestamp of the last time the position was increased
  • value at: positionIndex * 9 + 6
• hasProfit
  • 1 if the position is currently in profit, 0 otherwise
  • value at: positionIndex * 9 + 7
• delta
  • amount of current profit or loss of the position in USD
  • value at: positionIndex * 9 + 8

Buying / Selling MLP

Buying and selling MLP can be done through the GlpRewardRouter. To buy MLP, call mintAndStakeGlp

• _token: the token to buy MLP with
• _amount: the amount of token to use for the purchase
• _minUsdg: the minimum acceptable USD value of the MLP purchased
• _minGlp: the minimum acceptable MLP amount

To sell MLP, unstakeAndRedeemGlp

• _tokenOut: the token to sell MLP for
• _glpAmount: the amount of MLP to sell
• _minOut: the minimum acceptable amount of tokenOut to be received
• _receiver: the address to send tokenOut to
• Note that MLP can only be redeemed up to the reservedAmount, which is based on the amount of open interest, if the pool has been fully redeemed up to the reservedAmount then redeemers will need to wait for positions to close before further redemptions can be done, in this scenario the borrowing fee APR would be very high so liquidity providers will be incentivized to mint MLP and traders will be incentivized to close positions

The price of MLP can be retrieved from the GlpManager contract.

• The buy price would be getAum(true) / glpSupply
• The sell price would be getAum(false) / glpSupply glpSupply would be the totalSupply value of the MLP token.

Transferring Staked MLP

When MLP is bought it is automatically staked and when it is sold it is automatically unstaked, for integrations adding MLP, the StakedGlp contract can be used to transfer staked MLP tokens.

StakedGlp behaves like a regular ERC20 token, the user can call approve on it to approve your contract, then your contract can call transferFrom to transfer the MLP tokens to any receiving account or contract. When transferring, the StakedGlp contract will unstake MLP from the user and stake the MLP for the receiving account, the receiving account or contract would then start earning rewards which can be compounded or claimed by calling handleRewards on the RewardRouter contract.

Since there is a 15 min cooldown duration after minting MLP, this amount of time needs to pass for the user before transferFrom can be called for their account.

MLP Price

The price of MLP is based on the total worth of all tokens in the pool and factors in pending profits and losses from all currently opened positions.

• Buy price: glpManager.getPrice(true)
• Sell price: glpManager.getPrice(false)

Since there might be a spread for token pricing, passing in true into the getPrice function returns the maximum price at that point in time, while passing in false returns the minimum price.

Staking

The RewardRouter contract handles the necessary actions needed for staking in a single transaction.

When staking MPX:

• The RewardRouter deposits the MPX token into the StakedGmxTracker contract
• The StakedGmxTracker issues itself as a token for each token deposited
• esMPX can similarly be deposited into the StakedGmxTracker
• The StakedGmxTracker distributes esMPX to staked tokens
• After this step, the RewardRouter deposits the StakedGmxTracker tokens into the BonusGmxTracker
• The BonusGmxTracker distributes Multiplier Points to staked tokens
• Finally, the BonusGmxTracker tokens are deposited into the FeeGmxTracker which distributes FTM to staked tokens

When minting MLP:

• The RewardRouter sends the funds to be deposited to the GlpManager and mints MLP ****tokens
• The RewardRouter then deposits the MLP tokens to the FeeGlpTracker which distributes FTM to the staked tokens
• Finally the RewardRouter deposits the FeeGlpTracker tokens into the StakedGlpTracker which distributes esMPX to staked tokens

To get the deposit balances for an account you can use:

• RewardTracker.depositBalances(account, token), or
• RewardReader.getDepositBalances(account, depositTokens, rewardTrackers)

To get claimable rewards you can use RewardReader.getStakingInfo(account rewardTrackers), this returns an array of uint256 values in the order:

• Claimable rewards
• Amount of reward token distribution per second
• The average staked amount for the account
• Total rewards distributed to account