So I'm looking into an idea I had last night about a way you could simulate water within a container without actually simulating fluid at all.
The mesh is two cylinders, one very slighting within the other. I'm looking to figure out a way of having a similar effect to this screenshot, but only aligning the "water line" (opacity) with the world, and the fullness of the container would be driven by a parameter. As it currently stands, moving the meshes up/down would effect the 'fullness', rather than just the rotation of the mask aligning with the world.
The idea here is that you could have quite interesting materials for things like a water bottle that would almost look like it's contents is keeping with gravity.
I'm open to other ideas about how this could be achieved also, but I feel like if this method is possible it could be quite performance efficient too.
Here is my material so far for reference:
Any ideas? Thanks!