it seems peaple are still asking about delta time (which makes vitek write the code to them....about 25% of vitek posts is wrting this code lol...just kidding )
here it is the code we all know:
u32 then = device->getTimer()->getTime();
while(device->run())
{
// Work out a frame delta time.
const u32 now = device->getTimer()->getTime();
const f32 frameDeltaTime = (f32)(now - then) / 1000.f; // Time in seconds
then = now;
}