Module for filtering

[mistrjirka]

Hello, I want to create module that will filter clothes by size. User will come to the store and popup will appear asking the person size. Only the clothes with this size will be displayed. I have not found a way to do that in documentation. Is there a way to do that? Basically I need a way to filter the products being displayed everywhere. I don't where to start, only way I know is make custom "product displayer" (something like ps_featuredproducts), where I would add some filter functionality.

PS: If this question is badly written, please tell me I will do my best to make it better.

Thank you for your time.