4 ms·
> When precision in coordinates becomes an issue, you make a transformation and use relative coordinates anyways. This. Celestia, for example uses 128 (64.64)
by JabavuAdams 16y ago
> When precision in coordinates becomes an issue, you make a transformation and use relative coordinates anyways.
This.
Celestia, for example uses 128 (64.64) fixed-point for positions.
The nasty case in games is when you're subtracting positions to get a relative result. It's okay to store all positions as fixed point, and then return a float for the difference operator.
In general, you're not simulating the whole large volume with the same fidelity. You might be simulating a certain volume around the camera.
- atakan_gurkan 16y agoMy apologies, I misunderstood the meaning of "simulation". I was thinking of a calculation where you compute the interactions between objects and evolve their positions and momenta accordingly. Celestia does not do this of course, it uses some time series where the coefficients are computed in advance. For these purposes using fixed point and/or integer arithmetic instead of floating points could be entirely appropriate, I do not know enough to form a preference.