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View Full Version : IEEE float point formats - are they reliable?



alexione
31-10-2005, 04:46 PM
Hi, everyone!

Are IEEE float point formats reliable for calculations? What I mean here is: do they guarantee that same calculations on two different computers will give exactly same result?

The problem I have is synchronization of collision detection results on two clients in the game. Do I need to synchronize them at all if I use standard FreePascal real types?

Thanks in advance... :)

Clootie
31-10-2005, 09:04 PM
No, you need to use integers.

Sly
01-11-2005, 01:17 AM
What he said. I've found this from working on Playstation2, Xbox and Gamecube. The results from the same calculations may vary in the slightest fraction, exposing an error on one console while it seems to work fine on another console.

alexione
01-11-2005, 09:41 AM
Yeah, I was affraid it is so... Ok, heads up, let's do some math!

Anyway, thanx for your answers...

And, THANX to Clootie for DirectX headers :)

Clootie
01-11-2005, 09:39 PM
:roll: