What title is this occurring in? Or is this a problem in every title?
You might be talking about Motion Compensation? The car always facing forward and NOT connected to the way my headset is facing, has NEVER been a problem for me, and my base stations are in the corners of my room, so it doesnt anchor to a base station. So im think youre talking about MC.
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@adhoge I believe I know what you need. Or what you might want :). You want to anchor the nominal (i.e. the reset) headset position to the plane of symmetry of your cockpit, with the nominal orientation (i.e. the forward look) with being in the same plane as well.
Then depending on how much close you want your physical setup to match or resemble the virtual cockpit in the game you may need to āanchorā the remaining degrees of freedom as well and if you go that route you will also need to fine tune the game offsets, because the game has no idea where exactly are the features you want to match to their real counterparts (i.e. is it your steering wheel, your seat, or your pedals, which may be laid out differently relative to each other in the game and in your setup).
Even when starting easy, with only the symmetry plane, it is not that trivial (as you already noticed).
First of all, it really does not depend on where you place your basestation. You may feel that placing it in the same plane may ease things a bit, and it might (but only a bit), but you would also need to know the exact angle at which the base is looking at your cockpit and getting both right (the exact placement and measuring the angle) will eventually end up with having to do some measurements anyway.
So letās assume you have a basestation at a convenient spot, not necessarily in any particular relation to the cockpit (I would agree with @dstar suggestion that having it offset to one side is usually better).
Then, assuming you do not move your setup, i.e. the simpit and the base are fixed on their positions, you can do a measurement once, using whatever you have: headset, puck tracker, etc. You just need to get the coordinates of two points on the symmetry plane, for example at the front and at the back of your cockpit and assuming your simpit is level (not mounted on some slope), the two points will be sufficient to define the plane. Knowing the base coordinates (this you know, as SteamVR gives you them as well), you now have the geometry = the plane pose relative to the base.
Now comes the tricky part (which I have not tried myself, so it is just an assumption, how I would try to approach it):
- You put the headset into the position which you would your game register as āzeroā pos and do the SteamVR calibration. This will produce new chaperon config in
chaperone_info.vrchap. - Then you recalculate the calibration using the geometry you measured by the method above and find the best/closest spot in the symmetry plane and modify the chaperon data respectively.
- You will also need to remove any ācalibrationā set up in the game and never do āresetā position in the game.
This was the easy way :). You can automate the steps by mounting a tracker (or two) on your simpit and then do the measurement everytime you activate the system. But if your game does not allow āunresettingā the zero position, then you might need more hardcore approach, with hooking the SteamVR runtime to make it supply a fake pose for the game and reseting the position in the game using this fake pose. This goes beyond a forum post, but if you get to that, I guess you already know what you are doing.
EDIT: The lighthouse tracking has a tendency to ārecalibrateā itself, which could impact the statically measured and calculated data. So an āautomatedā solution could be more desirable.
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Itās not a āproblemā, it is just impossible to mathematically center your car perfectly with the direction of your physical simracing rig. Your centerline will always be somewhat off of the theoretical perfect center line, leading to your car always being a degree or two off angle. No, I am absolutely not talking about motion compensation at all.
The car always facing forward and NOT connected to the way my headset is facing, has NEVER been a problem for me, and my base stations are in the corners of my room, so it doesnt anchor to a base station. So im think youre talking about MC.
I am not talking about motion compensation. Nothing is being compensated. Please read my explanations. Here is a test. Sit in your rig, look forward. Press reset, open your eyes. You are in your car and facing forward, all is fine. Now look left 45 degrees while in vr, hit reset, then move your head back to looking forward. Where is the nose of your car? It is 45 degrees to your left. This is wrong, this means you have to āaimā the center line of your VR to be in sync with the center of your rig so everything feels 1:1 and aligned. This is impossible currently.
Imagine a perfect center line through your body, like a string going through your chest in front of you. When you are in VR, you are trying to align that center line with the theoretical center line of your rig, but it is impossible. Wherever you look, that is the direction the center line will be projected. This is wrong. The direction of the car should always be facing the perfect center point of my rig. This is defined by the base station that I have perfectly centered on my rig.
Take a string, and glue it to the base station in your mind. Drag the other end of the string to your VR headset. Wherever you move your head, that center line (the string) is always anchored to the front, always fundamentally pointed in the same direction, the car follows this string.
I literally have no idea how else to explain this, sorry 
Nothing is ābrokenā, everything works perfectly. I race every day. This is an improvement on getting your car perfectly centered and facing the same perfect angle direction of your physical rig.
No youāre overcomplicating it I think. Draw a line through your head, out of your eyes. wherever you ar elooking, center point is projected that way. instead of that, I want center point to anchor to base station in front of me. Draw a line from the center of my rig where base station is to my headset. Thats the angle I always want to maintain. Regardless if im LOOKING left, it doesnt matter, where im LOOKING shouldnt influence where the center line is prijected.
YOu know in the steamvr theater view thing, you see a bunch of circles and lines going outwards, and one of these lines has an arrow on it? Well if I look 45 degrees left and click āreset seated positionā, of course that arrow is now pointing where I was looking.
This is wrong, It should draw that center line through the origin of my headset, to the base station. If i stand outside my rig, look left 45 degrees,a nd press center, center line should not be 45 degrees. it should be drawn from my headset position, to the base station.
This actually is an issue that MC fixes and you might be missing the point. You use a ātrackerā - vive controller, tracker, etc. anchorit somewhere, turn on MC, and it now tracks where that DEVICE is facing - not your headset. I can reset the view all i want but its still straight based on which way the TRACKER is facing - not my headset. Ive had success with a cheap tracker that SimRacingStudio made work - its called witmotion.
Motion Compensationās exact point of being developed was because we needed to have the view anchored to our rigās orientation and movement. have you ever tried Motion Comp?
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WIth MC you can āanchorā the tracking to the tracker (instead of the basestation), but you are still facing the same problem, how to ensure that the headset in the zeroed position is looking exactly at the tracker (or that it is in the same plane).
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It is how resetting position typically works. It takes the actual position as a new āzeroā a changes the nominal yaw to the current one. Roll and pitch are not āresetā as it is assumed that we usually want to maintain the same/natural horizont and/or elevation.
Anyway, you can use basestation instead of the (one) tracker, if you place the basestation into the aforementioned āsymmetry planeā, but the procedure to achieve what you are trying is basically the same. You may need to do some hard work and some programming. There is no function (in SteamVR), which does that.
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You may need to do some hard work and some programming. There is no function (in SteamVR), which does that.
Yeah thats fine, basically itās just getting the difference between my current look forward angle, and where the base station is, and redrawing/repositioning or whatever. i only care about the 3d location of my headset, not where it is pointing.
Holy crap really? Thats basically exactly what I need.
Motion Compensationās exact point of being developed was because we needed to have the view anchored to our rigās orientation and movement. have you ever tried Motion Comp?
That makes so much sense lol. No I havenāt. Sorry for spazzing! I will look into this because this sounds like exactly what I need - just car always pointing forward.
What should I google/lookup for this? I have a Pimax and a 1.0 Base Station. I saw some āmotion compensationā thing in the PiTool?
I will look into Witmotion. Do you have any videos or resources on anything related to this?
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It shouldnāt be a big problem at least in theory. The origin (starting point) of my headset will be set, which is fine, and then a center line drawn from headset to base station. It knows where the base station is as Iām actively looking at it in the theater or w.e view and I can see it in 3d space. It just needs to ignore where Iām looking and only pay attention to where my headset is
Iāve found an interesting link here that may be relevant to what Iām trying to do. Sim Racing Studio OpenVR Motion Compensation Guide : Sim Racing Studio
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YES!!! thats the one for SRS. Theres more out there. They made a unique one with a VERY cheap Witmotion tracker. I had to buy 2 more because the first 2 failed later on but theyāre so cheap i didnt care.
The tracker will be your new viewing position. You place it with the connector sticking out forward and thatās your new position. You will want to place it on your rig in a place where itās closer to the center of gravity. if you place it forward or aft too much, the changes in pitch may be too much, but even that can be changed in the software i believe. The rest of the software is basically getting to know OVRMC - theres a discord as well, but its barely active there.
There is also MC in that pitool software that i tried and incredibly it actually worked when i tried itā¦ You may want to try using their built in MC as well.
Lastly, theres a new dev behind a new kind of MC thats supposedly getting really good reviews from people. Itās called OVRXC-Motion Compensationā¦ you can join their discord here OpenXR-MotionCompensation
Theyāre more active and continuously making more updates as it seems OVRMC slowed down as it works as it should already.
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So basically I place this thing somewhere on my rig, calibrate it, and my center will always be fixed depending on the calibration of this witmotion device? BTW my rig isnāt motion. My singluar goal is to just have my car pointed the same way 24/7 so I donāt have to wiggle my head around and try to get it perfect hitting ārecenterā 100 times.
I want my car nose in game to always be locked to that base station in front of me (or something else) is all. Youāre saying the MC stuff can help me with this then?
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Iām really curious about this too. I also donāt have motion on my rig. But can a Vive Tracker be mounted to my wheel base, which is in front of me, and that be used to lock in the x-axis (forward/backward axis parallel with the floor)?
Dont you mean yaw? Surge being the direction your rig is facing, and the direction you want your car to face in VR. the problem is the yaw of the VR headset determining the surge direction, when surge should be in sync with your physical rigs surge
is that what you meant? describing and reading spatial problems is so hard lol
Is your problem nailing the heave to align your wheel? because mine is a problem with getting the perfect yaw so my car points in the perfect direction in sync with my rig, not a small degree off of the yaw
My problem is the same problem as yours. Re-centering the headset vs my perfectionism/ocd lol.
Explaining the problem appears to be as hard as it is to get the car perfectly lined up.
Maybe 2 trackers, both in inline with the center of the driver. One in front and one behind.
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OK perfect and hahaha yes it does, nightmare thread. I apologize in advance to everyone whos come across this thread.
Thats what I was thinking, then some clever math with offsets to place the headset in space.