Ext 11 for multiple spin games ensure multiple vrf calls are used

[giovannifranchi]

Changes implemented:

• A constant wish represents the standard number of words for oracle request (2) has been added
• All functions requiring _requestRandomWords() or _requestRandomWordsSupra() now perform a loop making a VRF request for each number of mints. The aforementioned functions are namely:

    1. _attemptBatchMintForEthWithEth()
    2. _processMintForEthWithEthAttemptSupra()
    3. _attemptBatchMintForEthWithMint()
    4. _attemptBatchMintForEthWithMintSupra_requestRandomWordsSupra()
    5. _attemptBatchMintForMintWithEth()
    6. _attemptBatchMintForMintWithEthSupra()
    7. _attemptBatchMintForMintWithMint()
    8. _attemptBatchMintForMintWithMintSupra()
    9. _attemptBatchMintWithEth()
    10. _attemptBatchMintWithEthSupra()
    11. _attemptBatchMintWithMint()
    12. _attemptBatchMintWithMintSupra()

• Due to a stack too deep error in compilation the function _attemptBatchMintWithMintSupra has been polished of some variables. The previous variables have been replaced either by direct function invocations or direct math computation in the most gas efficient way possible.
• Since the resolve mint functions don’t always receive a predictable number of words (some of those values are parametrised therefore changeable) in order to allow the protocol to be resilient to future parameter changes it has been decided to leave the already existing structure based on loops.

[giovannifranchi]

Variables in memory use 32 bytes in any case because of how Solidity works. Using a uint8 instead of a uint256 actually increases the cost of operations since under the hood solidity converts the uint8 in uint256. As an example a made a dummy contract which performs a for loop of 50 iterations.

As we can see the transaction cost of the loop performed with uint256 is 46538

while for uint8 is 46822

For what concerns ++i instead of i++ I can confirm there is a small gas saving (46538 - 46310 = 228) which could be considered negligible, especially considering contracts operate on L2s and the contract I made performs 50 iterations. Nonetheless I will apply this change.