Pricing Modules

Pricing Modules are utility contracts that implement the IPricingModule interface and are used by the BiPoolManager during swaps to price the swaps. A pricing module has to implement two functions:

uint256 amountOut = pricingModule.getAmountOut(inBucket, outBucket, spread, amountIn);
uint256 amountIn = pricingModule.getAmountIn(inBucket, outBucket, spread, amountOut);

mento-core/contracts/interfaces/IPricingModule.sol at develop · mento-protocol/mento-coreGitHub

IPricingModule.sol

ConstantSumPricingModule

$$x+y=k \newline (\Delta x + x )+ (\Delta y + y) = x + y \newline \Delta x = - \Delta y$$

ConstantSumPricingModule is an IPricingModule that implements a constant-sum pricing formula for a two-asset pool.

https://github.com/mento-protocol/mento-core/blob/develop/contracts/ConstantSumPricingModule.solgithub.com

ConstantSumPricingModule.sol

ConstantProductPricingModule

$$x*y=k \newline (\Delta x + x)*( \Delta y + y) = x * y \newline \Delta x * \Delta y + \Delta x * y + \Delta y * x + x * y = x*y \newline \Delta x ( \Delta y + y ) = - \Delta y * x \newline \Delta x = - \Delta y * x / (\Delta y + y)$$

ConstantProductPricingModule is an IPricingModule that implements a constant-product pricing formula for a two-asset pool.

https://github.com/mento-protocol/mento-core/blob/develop/contracts/ConstantProductPricingModule.solgithub.com

ConstantProductPricingModule.sol