I've given this some thought, and I don't really think any of the suggested alternatives are any better than just assuming people will figure out that 16777215 is just (1<<24)-1.

* 0xFFFFFF won't work since it breaks the hlsl shader compiler
* (1<<24)-1 is sort of ugly too, and hence potentially even more confusing
* adding some MAX_UINT24 definition is also just ugly.. it's either defined as the string "16777215" so you end up with things like `out.Write("int depth = zCoord *" MAX_UINT24 ";\n");` or it's the number 16777215 and you need to use `out.Write("int depth = zCoord * %d;\n", MAX_UINT24);`. Both things don't make it any easier to grasp what the code is doing.

What do you think?