Not entirely sure this will still protect from anything, shortish:
* Remove cancelling due to coarse pre-checks.
* Rather correct the end location back onto the end block somehow.
* Retry ray-tracing with the pitch and yaw of past flying packets.
* Let the direction check handle the off-too-far part and let people
blame that one for remaining amounts of false positives.
Missing:
* Should confine by distance to last move, perhaps.
Use check-specific debug methods for convenience.
Add to: Check, CheckListener, BaseAdapter.
Relay to: CheckUtils.
Side effects:
* Remove constructor: CheckListener().
MISSING:
* Micro move onto ground, fall distance resets before sf check is run.
Done:
* Split PlayerMoveEvent processing to from -> loc + from -> to. Just if
from isn't the same coordinates as player.getLocation. This
reduces the complexity of workarounds.
* You do take fall damage falling onto slime blocks while sneaking.
* Queue bounce effect, only if the move is valid. Skip NoFall then.
* Apply bounce effect once moving up, to allow overriding.
* Cover more odd cases.
Unrelated:
* Use data.debug instead of cc.debug.
* Queue outgoing positions in order to detect ACK on incoming.
* Since we can't detect relative teleports, positions are only queued,
if they match an absolute location from a teleport event (Bukkit).
* The queue is kept simple: only store the latest position.
* Cancel incoming flying/pos/look until ACK is received.
Missing:
* Are yaw/pitch are ever sent back changed.
* Configuration to turn it off.
* Might use this to just skip all violation handling until ACK.
Cancelling redundant packets has to big problems:
* The normal case is to not run in the primary thread.
* For legit players a missed micro move could mean that survivalfly can
not detect ground properly.
Better approaches could be:
* Cancel asynchronous packets if they match the last sent one (only
simple hacks).
* Check for moves passing block borders, request block shapes and such
from the main thread.
* Detect actual cheating or unusual patterns instead.
* Queue packets for processing in the main thread.
Missing:
* Actually detect ACK packets for previous outgoing teleports.
* Do something upon detecting illegal coordinates (asynchronous
disconnect? queue kicking, config).
* Update lastKeepAliveTime from KeepAliveFrequency (even if that is
disabled).
* Update lastKeepAliveTime from FlyingFrequency too.
* Allow to test for feature tags efficiently.
* Extend CheckConfigFactory with a remove-all method.
* DataManager.clearConfigs() now uses CheckType for getting factories.
* Split off Check.hasBypass method to check exemption + permission.
* Allow null permissions in CheckType (interpret as no bypass).
* Add Check types for FlyingFrequency and SoundDistance.
* Add exemption and actions to FlyingFrequency, alter defaults.
First attempt to detect if a moving event would fire. This might not be
100% accurate, as a) we can'T really know and b) lastTo is not minitored
in the most reliable way (e.g. teleport on highest priority, resetting
logic favors set-backs).