It's easy to create a fabric that blocks the rain. It's much harder to create a fabric that blocks rain but still allows your sweat to escape. However, the same principle works on all waterproof fabrics: diffusion. Molecules are moving from high concentration areas to low concentration areas. Therefore, when you warm up and create moisture, you want it to go through your waterproof hunting jacket and reach out to the lower concentrations.
This is achieved in various ways by different waterproof materials. The most functional waterproof material, used by various companies nowadays, is extra durable fabric 20,000 mm+ in the waterproof rating scale. It is rain and waterproof under very high pressure and used ultimately in rain gear production, construction, and garden equipment development.