Reverisble Vs. Unreversible Events

[Baker]

This is from the perspective of demo rewind for NetQuake.

Reversible events in Quake:

1. Most entity positioning and frame animation interpolation.
2. View bobs, idle animations
3. The clock displayed, of course

4. Anything that is a direct calculation of the current time:
4a. Sprite animation
4b. R_TextureAnimation (animated textures)
4c. Sky scrolls
4d. Water warping animations
4e. Skin group animations

Irreversible events in Quake ... Client side effects:

1. Temp entities, their dynamic lights and particles.
2. Status bar flashes, damage flashes, face animations.
3. Fog transitions.
4. A limited few aspects of movement/frame lerping in some situations (if it relies on one-time server flags)
5. In a trivial way, centerprint (expected to stay on-screen for 3 seconds).
6. Map change.
7. Sound. Cd track changes.

[Spike]

many of your 4X things are a product of the client's uptime rather than the server's gametime, and will vary from one client to another.

for the sake completeness, you don't mention killed monster/secret counts.
you also don't mention console prints (svc_print), which persist on the console. if you're often rewinding over the same short period, you may want to remove such prints too.

[Baker]