Where is the time the last tick took, avg tick took etc.?

[thebest108]

So I added a variable timestep to my physics simulation, and I want to make the speed things move independent of server lag by changing the speed from 1/20 to how many ticks happened in the last second. Where does Minecraft keep these things?

[jabelar]

I've played with this before and like diesieben07 mentions it usually doesn't result in what you think -- you can fairly easily make the physics honor real time (I'll explain how below), but when everything else in the game is lagging it is really weird when the physics works real time. Basically it is just much more playable when everything lags together.

 

But, if you want to play around with it, you can use Java's System.nanoTime field to measure the time each tick is taking and adjust accordingly. Basically, you need a field to hold the result of System.nanoTime from the previous tick, and you need a field for the time for current tick. You can update these in the tick events (probably the client tick and server tick events) where you copy current time to the previous time, then update the current time from System.nanoTime.

 

Then you just need to compare what the tick took relative to what it should be. There is supposed to be 20 ticks per second so each tick should be 0.05 seconds = 50 miliseconds = 50,000 nanoseconds. So to adjust things for this lag, you would use a scaling factor of (currentTime - previousTime) / 50000.

[thebest108]

Of course, I just record the system time the last time i ran the tick, and subtract the current time.

 

Better than rummaging through MC code anyway.

[Draco18s]

Then you just need to compare what the tick took relative to what it should be. There is supposed to be 20 ticks per second so each tick should be 0.05 seconds = 50 miliseconds = 50,000 nanoseconds. So to adjust things for this lag, you would use a scaling factor of (currentTime - previousTime) / 50000.

 

Its not 50,000 nanos.  It's 50,000,000.  Mili, micro, nano.

 

https://en.wikipedia.org/wiki/Nanosecond