Possible to make payments with a point system?

Hi!

I am exploring Snipcart as a possible solution for an online Reward Store, something like Air Miles, in which you can purchase products with points that you have accumulated. We also need to support hybrid payments (ex: purchase a product with 500 points AND an additional $10).

Is there a way to do something similar with Snipcart? I assume that it’s possible using a custom payment gateway, but I’m not sure how it would work in terms of currencies.