I saw that the default lit shader does support channel packing. Which is good! The problem is that for some reason the channel packing is not as optimal that is could be. Is there a reason why the default lit shader doesn't use the Blue channel for the height/parallax map so that we can combine more of the shaders together into a single texture? A better option would be to somehow specify which channel we have encoded to each of these maps, but I'll take a hard-coded value for now. Yes, I could write our own shader, but there are a lot of other benefits to using the default lit shader (it's the default, has checkboxes for reflections/specular, additional maps, etc.).