Any way to mask part of a mesh with another mesh?

In my game I have large lakes that I freeze over during winter seasons. This is currently just a large plane with collision that I place over the surface of the water.

I’d like the allow the player to create holes in the ice.

Is there anyway to create some kind of mesh mask so that I can make it look like there is a hole in the ice (even if the hole is only visual)?

I think the best way to do that is with a decal. To make the hole look deeper, use UDK | DevelopmentKitGemsParallaxOccludedMapping. Do you need to see what’s actually under the ice? Then you would probably have to do something similar to your minimap the way you mask out areas.

you can use the HitMask feature which would allow you to use it as a mask and do anything in the material with it, including holes in the opacity (but not collision holes)
its feasability would depend on the size of the lake (resolution of the mask) and the amount of lakes you have

Thanks for the ideas guys. Yes I think using a mask in the material will work. It’s a shame there doesn’t seem to be anyway to create masks in collision, so that players could move through the holes.