: In Blender the method is called Environmental reflect and easily done in
: post. But getting Real-Time Reflecting(RTR) is much harder to do over 2-4
: way online splitting. The more you RTR the more ram and processing is
: needed. Multiply that by 2-4 players that are states/countries apart and
: you get lag.

More RAM and processing is needed for real-time reflections, but that should have negligible effect on networking performance. Games are almost always rendered locally, it's not like the host is having to expend extra processing power (or upstream bandwidth) for your locally-generated real-time reflections.

It's hard on the GPU, not your internet connection.

: In Crysis, I think they have a back-up code to pop in a
: Environment/World/"Box" map to prevent lag. There is a lot of
: details doing on in that game. Some cheats are needed.

The cubemap popping in isn't a result of trying to prevent lag, it's how they deal with the fact that screen-space reflections often won't find anything to reflect (due to only being able to reflect things currently being drawn on screen). If the ray never hits anything, they assume it escaped off into the sky or something (sometimes a correct assumption, sometimes not), and so just stick the cubemap result at the location where the ray is cast.

It absolutely is a "cheat" in a sense, but it's not a cheat to improve computational efficiency. It's a cheat to try and bandaid up the intrinsic deficiencies in screen-space reflections.

: I do miss RTR in Hal's campaign, but I understand why they took it out. They
: also took out transparency in areas as well. Keep in mind that Halo6 will
: be on the next Xbox. Hopefully these issues will be fixable by then.

They won't. The reason that proper planar reflections are expensive is that you need to re-render the scene from another angle. Extra renders become more expensive as the baseline graphics themselves become more expensive. This is why these crappy screen-space reflections are becoming popular; they don't require an extra render, and have a per-pixel cost which does not increase with respect to graphical complexity. If we still have current-gen-esque graphics, then sure, proper planar reflections are going to be easily doable next gen. But if developers push the platforms to their knees before considering planar reflections, it isn't happening.