i was advised to use a callback for physics calculation instead of display function.
Yesterday i might have find out why. Two people with two times higher latency one from another tested kinghill2-like server.
And with different hardware also (i guess). The person with higher value of ping was constantly faster driving his car, while they both should have identical performance.
A propos - why Mania Drive did not follow this rule?
Another thing: on windowsXP time counter broadcasted from server to client had some random value ( at least i was told so) while on every machine i used ( two win7 and one linux 3.10.17) it was correct? What could be the reason ( i will try to check it for myself in some time).
My goal now is to make this game system work as expected.