This used to be a configuration option because spectator mode and "net"
mode were incompatible. When the ability to switch between player and
spectator was added, the configuration option was removed, since it was
no longer a mode toggle. This re-adds it, mainly so that I can use it to
implement regression tests.
This patch transfers core_reset across netplay. Resets effectively
worked before thanks to check_frames, but this makes resets work even
without check_frames, and in particular should allow resets to force
sync in savestateless cores, bringing them one step closer to actually
being usable by non-experts.
Previously, the host would time out waiting for the guest to enter a
password, as the timeout was not conditionalized on whether the guest
was actually playing. This fixes that.
Previously, if two clients were connected to the same server and one of
them was ahead of the server, the only way to rectify that situation was
for the client to get so far ahead that it stalled, as the server could
only catch up with an ahead client if all clients were ahead. That's
unrealistic. This gives the server the alternate option of demanding
that a client stall. This keeps things nicely in line even with >2
players.
Previously, we could be stalled by one player but still reading data
from another, which would wedge the client because we would never act
upon the newly-read data. Now we act upon data even if we're stalled.
Fixes bugs in initial connection with high latency.
The idea:
* Use a fixed number of delay_frames (eventually to be fixed at 120,
currently still uses the config variable, 0 will still be an option)
* Determine how long it takes to simulate a frame.
* Stall only if resimulating the intervening frames would be
sufficiently annoying (currently fixed at three frames worth of
time)
Because clients always try to catch up, the actual frame delay works out
automatically to be minimally zero and maximally the latency. If one
client is underpowered but the other is fine, the powerful one will
automatically take up the slack. Seems like the most reasonable system.