Leaning when looking behind

Posts: 18
Joined: Thu Nov 10, 2005 5:00 am

Re: Leaning when looking behind

Post by ZyronEnder » Wed Dec 14, 2005 1:23 pm

I completely understand what you are saying. I've noticed this myself particularly when playing Flight Simulator 2004. I often like to turn my head and look out the side window towards the ground and I find it disorienting that once my head is turned, any side/side motion is translated wrong.

I read in an earlier post that NaturalPoint hired a couple of math people to help improve their algorithms. Hopefully this will be straightened out in a software update.

Posts: 10
Joined: Fri Jan 21, 2005 5:00 am

Leaning when looking behind

Post by Peccator » Wed Dec 14, 2005 5:07 pm

When I lean my real head left my virtual head also leans left. This seems obvious, but I think it is incorect when my virtual head is rotated .

Say I'm looking over my left shoulder with my virtual head. I want to look at the planes tail better, so in relation to the plane I want to lean left (port), which is right in relation to my virtual head, but left in relation to my real-world head. So should I lean my real world head to the left or right. Currently the trackir program says I should lean to the left, but my natural inclenation is to lean to the right.

Also, say I look 90 degrees to my left and then lean to the right. What should happen is that my in game head should move towards the front of the plane, not towards the right of the plane.

In my opinion, the trackir software is handling translation wrong. All translations are with respect to the real world head. I believe all translations should be done with respect to the virtual head. In my mind this is the "correct" way to do it, but if you disagree with me, please at least make my way (translations in respect to virtual head) a software option.

Is this clear? Or should I explain in more detail?

*EDIT* I imagine that this is also true for y and z-axis translation (assuming z is in/out and y is up/down). Say I look down to see a gauge and then leen towards my monitor to get a better view. I believe that the virtual head should move toward the gauge that I am currenly looking at. I should not have to remember which direction my virtual head is looking so that I can translate my real-world head in that direction, I should just be able to move my head towards the screen. If I am remembering right (I am at work right now, so no TrackIR to test on), the way the software works now is that it translates forward (with respect to the plane) when I lean forwads which may well take the object I'm trying to lean towards out of focus.

[ December 15, 2005, 09:03 AM: Message edited by: Peccator ]

Posts: 21
Joined: Mon Mar 21, 2005 5:00 am
Location: Birmingham, UK

Re: Leaning when looking behind

Post by DickDastardly » Mon Dec 19, 2005 2:03 pm

I'd really like this to be changed too, or at least made an option. I too think the way translation is currently implemented is wrong.

The problem can perhaps best be illustrated by considering the situation when your virtual head is looking at 90 degrees to the left. If you then want to move your virtual head in the direction of your virtual gaze then your natural inclination is to move your real head towards the image of the left side of the cockpit which you're currently seeing on your monitor. Unfortunately in the current implementation doing so will actually result in your virtual POV moving towards the front of the plane, not the left of the plane.

If you think about it, this is unnatural - to function TrackIR relies on the fact that the information your brain receives visually carries more weight than the information it receives kinaesthetically (about the actual position of your real head). Thus when using TrackIR you get a convincing feeling of looking all around a virtual cockpit when in actual fact your real head is only making very small movements, never more than a few degrees in any direction from the monitor. In other words the illusion depends on you forgetting the position of your real head and focussing on the position of your virtual head instead. It therefore seems perverse to handle translation relative to your real head (the current system) rather than relative to your virtual head.

If this could be changed I think it would greatly improve the illusion of being "in the game" which TrackIR use gives you as
your head movement would be relative to your virtual head position and therefore consistant with the virtual visual image you're seeing, rather than being relative to your real head position but in conflict with the visuals.

[ December 19, 2005, 09:24 PM: Message edited by: DickDastardly ]

Posts: 581
Joined: Thu Jul 07, 2005 5:00 am
Location: Philomath, OR

Re: Leaning when looking behind

Post by rodom » Mon Dec 19, 2005 5:19 pm

For a temp fix you could always invert the roll within the profile you use.

Posts: 10
Joined: Fri Jan 21, 2005 5:00 am

Re: Leaning when looking behind

Post by Peccator » Tue Dec 20, 2005 1:38 am

quote: For a temp fix ... Can I take this to mean that any fixes I make will be temporary because you guys are working on the problem? I hope so.

BTW, I think you misunderstand. My problem is not with ROLL but with TRANSLATION. I usually turn roll off altogether (for me it adds more complexity than benifits).

If you meant to say that I could invert my left/right translation, I've actually thought of that, but I'd need to be able to uninvert it every time I looked forward and reinvert it everytime I looked backwards. Plus the 90 degree head turn still wouldn't work (which would probably be great for trying to see below your own plane). But I don't think I can assign a shortcut for inverting/uninverting, and I don't think its worth asking for as it doesn't really solve the problem.

The real solution I think would be to rework your translation/rotation matrices. This should be relatively easy. I've coded it in class and every 1st person shooter has them right. Think about it, in a 1st person shooter, if you rotate your view to the left (with the mouse), and press forward, your charactor moves forward in respect to their new direction, not in respect to some fixed coordinate system.

Also, if you do change your matrices and find you like the way you are currently doing rotations/translations you can always make what set of matrices are being used a user selectable option fairly easily.

Lastly, I realize I'm making assumptions about how your software is implemented that may not be true. Maybe you didn't use matrices and so changing them will be very hard. I understand that every code base is different and some things that should be easy aren't.

[ December 20, 2005, 08:47 AM: Message edited by: Peccator ]

Posts: 10
Joined: Fri Jan 21, 2005 5:00 am

Re: Leaning when looking behind

Post by Peccator » Tue Dec 20, 2005 2:02 am

quote: If you think about it, this is unnatural ... the illusion depends on you forgetting the position of your real head and focussing on the position of your virtual head instead ...I couln't agree more Dick. I think you cut to the heart of this issue better than I did with this paragraph -- the illusion is lost.

NaturalPoint Employee
NaturalPoint Employee
Posts: 1395
Joined: Mon Oct 14, 2002 5:00 am
Location: Corvallis, Oregon

Re: Leaning when looking behind

Post by Jim » Wed Dec 21, 2005 10:08 am


We are aware of the situation that you describe above. We have experienced it for ourselves. We have looked into solving this problem several times and the answer is that it is very hard, if not impossible, to do.

Essentially, we do know exactly where you (your head) are in 3D space, and we know what information we are sending to the game to represent this scaled movement. The problem is that we are an absolute positioning device, so we must always have a dead center. If we "correct" the view problem then we could not be absolute because there is more than one solution to how you could arrive at the virtual head position you would desire. So, there are several ways you can move your real head to get into the exact same virtual head position, if the problem is "fixed" and therefore we can not guarantee that we are absolute, because how do we know which way was correct? You can move to the side and then rotate or translate again, or rotate first and then translate, the outcome is the same in the virtual view, but when you move back to your centered position it doesn't reverse out properly. Hope this makes sense.

We will continue to investigate this problem in the new year and hopefully come up with a good solution.

Posts: 20
Joined: Sat Mar 22, 2003 5:00 am

Re: Leaning when looking behind

Post by il2user » Fri Dec 30, 2005 8:48 pm

Here is a suggestion which I've thought about. Maybe it could help in this case, maybe not. No idea how well it would work, but maybe you can consider it?

Currently it is possible to turn TrackIR on/off. When switched off, the view updating stops and virtual head position and view direction stay the way they happened to be. This can be temporarily useful in some situations like when attacking a plane.

Would it be possible to add a new similar command to TrackIR software that would lock/unlock virtual head position only? If this was so, one could move the virtual head to some place in cockpit, lock head position and after that only the first 2 degrees of freedom would be in use. Then I could move my real head back to center position for best possible 2DOF tracking. If I looked left/right or up/down, those movements would be easily tracked by TrackIR. This info would be "sent" to the game as if my virtual head was in the locked position, but look direction would change in real time.

Once I'd want to release my virtual head position, I'd just press the head position toggle key again, and things would work like they are now: all X degrees of freedom defined in the profile would be used.

I think this kind of system could be good because it would improve tracking and one wouldn't have to keep one's real head in a difficult position for a long time:
-far left/right: tracking gets worse when you move away from the center
-near the monitor (looking instruments): leaning forward gets tiring quickly
-head high (peeking over the nose of the plane, say during landing)

What do you think?

Posts: 1
Joined: Tue Sep 05, 2006 7:37 pm

Re: Leaning when looking behind

Post by Kif » Tue Sep 05, 2006 8:11 pm

Has this been resolved?? I have been looking everywhere but all posts lead to a dead end. I know it is possible as in enemy engaged comanche hokkum it works fine but in FS9 it does not. Anyone know a fix??

i have track ir 4



Posts: 7728
Joined: Mon Jul 17, 2006 5:00 am
Location: Corvallis, Oregon

Re: Leaning when looking behind

Post by VincentG » Wed Sep 06, 2006 3:36 am

It should we resolved with the next release of the software drivers.

Post Reply