Question regarding DCS in 32 vs 64 bit

[Hummingbird]

So I was wondering, does the usage of 32 bit not limit DCS quite abit? I mean it is a game that involves quite large distances and as such wouldn't this cause issues in terms of floating point accuracy at the edges of maps?

 

I understand that Star Citizen went to 64 bit for this very reason, as in 32 bit once you've moved just 10 km from the center of origin you will have accuracy errors of 1 cm, and at 100 km 10 cm.

 

In other words once you've flown 100 km from the center of the map universe you would start to notice the pilot and cockpit not lining up, and at 200 km it would look quite misaligned.

 

How does DCS get around this problem, if at all?

[Rangi]

32 bit was dropped a couple of years ago, DCS is 64 bit only now.

[Hummingbird]

32 bit was dropped a couple of years ago, DCS is 64 bit only now.

 

Really? I was under the impression it ran on 32 bit.

[Grimes]

Hummingbird is talking about 64 bit integers and not the architecture that allows for more ram to be utilized. He likely just watched a recent video on youtube discussing the subject.

 

I think the position integers are 32 floating point. I think the only area where you see desync of objects is currently with aircraft parked on ships. Anything else will likely be relative to a different origin. Weapons, pilots, etc are relative based on aircraft. Ground vehicles may not be as accurate on the x and z axis at the extremes, but the y axis is just relative to the ground where the max value is around 5-6km so a mismatch isn't likely to occur.

[Hummingbird]

Couldn't this potentially cause issues with the multi crew aspect of the game? Or what about formation flying at the edge of the map?

 

I really thought that 64 bit position integers were a must for flight sims?

[Rangi]

Oh, way above my pay grade.........

[BaD CrC]

Hummingbird is talking about 64 bit integers and not the architecture that allows for more ram to be utilized. He likely just watched a recent video on youtube discussing the subject.

 

I think the position integers are 32 floating point. I think the only area where you see desync of objects is currently with aircraft parked on ships. Anything else will likely be relative to a different origin. Weapons, pilots, etc are relative based on aircraft. Ground vehicles may not be as accurate on the x and z axis at the extremes, but the y axis is just relative to the ground where the max value is around 5-6km so a mismatch isn't likely to occur.

 

 

OOoooh. So this is the reason why we cannot take off from ships (starting cold and dark) with a chopper without falling into the sea or hitting some parts of the boat and blow up?

If this is the case, does it mean we are not going to see this solve anytime soon?

[joey45]

I think that's a different problem all together..

[c0ff]

positions are 64-bit double float.

[Hummingbird]

positions are 64-bit double float.

 

That's the same as what Star Citizen will be using according to what I've read, so that is good news.

[Hyperion35]

That's the same as what Star Citizen will be using according to what I've read, so that is good news.

 

It's worth pointing out a key part of this sentence is the word "will be". Star Citizen has not yet been released, it is still in its development cycle. So anything that their development team is discussing is still theoretical and has not yet been implemented.

 

DCS, by contrast, is in full stable release and has been through several development cycles. There are still bugs, because there's no such thing as bug-free code, but unlike Star Citizen, they'd actually put their simulator code into action. So it might be better to say that it's good to hear that Star Citizen intends to implement the same sort of high-fidelity 64-bit floating point calculations that are already used in DCS.

 

Star Citizen is in a position where they can say that they intend to do a lot of things (and in fairness, their lead producer does have a long history of successful space sims), but DCS is in a position where they are expected to make it work.

[Buzzles]

It's worth pointing out a key part of this sentence is the word "will be". Star Citizen has not yet been released, it is still in its development cycle. So anything that their development team is discussing is still theoretical and has not yet been implemented.

 

DCS, by contrast, is in full stable release and has been through several development cycles. There are still bugs, because there's no such thing as bug-free code, but unlike Star Citizen, they'd actually put their simulator code into action. So it might be better to say that it's good to hear that Star Citizen intends to implement the same sort of high-fidelity 64-bit floating point calculations that are already used in DCS.

 

Star Citizen is in a position where they can say that they intend to do a lot of things (and in fairness, their lead producer does have a long history of successful space sims), but DCS is in a position where they are expected to make it work.

 

Going slightly off topic, but you do realise Star Citizen has an alpha build out and accessible to the public? A lot of the stuff, iirc including the 64 bit arch, has been implemented and is out.

 

Personally, what's really interested me with SC is their implementation of localised physics grids, allowing them to have players moving freely within and in/out of ships that are flying around space.

 

Very impressive solution to the problem which plagues lots of games*, and might actually be applicable for DCS with regards to carrier ops and future modules if we ever go big enough that we need to move around inside.

 

*updating player postion which is in relation to global grid when the player is within another moving object on said grid, and also dealing with collision mechanics.