This setup assumes you are using elapsed time to control distance moved per world update, so framerate isnt an issue.
also it is assumed that everything is expressed as forces applied to the entity, tho rotation forces arent handled, they can be easily added.
[vector (x,y,z) values]
P=position
V=force vector
N=Network data
[scalar (integer) values]
L=Local Entity
F=Future Entity
T=Timestamp
compute future timestamp
FT = LT + (prediction time offset, say 0.25 secs)
compute future position
FP = NP + (NV * (FT - NT))
compute vectors from local position to future position
LV = (FP - LP) / (FT - LT)
optionally use the computed local forces to rotate the entity to face in the direction of movement.
You will need some extra work to synchronize timestamps at net connect to make this work. Its not cubic splines, but it gets the job done.
also it is assumed that everything is expressed as forces applied to the entity, tho rotation forces arent handled, they can be easily added.
[vector (x,y,z) values]
P=position
V=force vector
N=Network data
[scalar (integer) values]
L=Local Entity
F=Future Entity
T=Timestamp
compute future timestamp
FT = LT + (prediction time offset, say 0.25 secs)
compute future position
FP = NP + (NV * (FT - NT))
compute vectors from local position to future position
LV = (FP - LP) / (FT - LT)
optionally use the computed local forces to rotate the entity to face in the direction of movement.
You will need some extra work to synchronize timestamps at net connect to make this work. Its not cubic splines, but it gets the job done.