Parallel projection Puns

There used to be a trick to bypass PP for games like PC2 as referenced in this post here. I had used this in the past, but can't seem to get it to work anymore. When I start a race, I get double vision. Does this workaround no longer work?

The last update fixed the stereo mismatch on certain vfx and planet flora, now on headsets with canted screens like Index and Pimax you can disable parallel projection compatibility mode for a big performance gain!

Also interesting are some new libraries that would imply DLSS support is incoming..

https://community.openmr.ai/t/no-mans-sky-no-more-parallel-projection-mode/35703

Can anyone help me understand parallel projection in Godot. Or a similar type of camera. I’m really slow at learning and I’ve tried to do similar attempts at the same type of camera Diablo or path of exile uses. I can read about it all day long and I’ll just grasp the basics. Can someone maybe dumb it down for me. Or point me in a direction to examples.

I remember seeing someone that had a pp fix for half life alyx. So we don’t need to have pp on. Thought I saved the post. Can’t find it. Anyone got that post saved thanks

Astral projection has been a part of my life since I was 9 years old. It’s been a close companion. An old friend that’s been at my side for the last 40 plus years. In the beginning, it was simply fun and games, floating around my room, soaring over oceans, and attempting to visit my first crush (I never quite succeeded at that, but that’s another story).

As I got older and gained more experience (learning to move with the power of thought, contacting my guides), I began to make trips to other worlds, and different planes of reality. When I was a child, I use to think it was the coolest thing to dive toward the ocean, then suddenly pull up… Until I visited a world where there were spherical homes that orbited in its atmosphere like satellites, or when I flew (with the assistance of my guides) to a field in another reality where I said hello to a giant house cat with eyes that projected light. I began to realize that astral projection was more than walking through walls or gliding through the clouds. The possibilities were limitless, but even then, as I began to truly discover what I could do, I could never have imagined my next step…

Five years ago I had an accident that almost cost me my life and now requires that I walk with a cain. It of course changed many aspects of my life, but there was one aspect I could never have foreseen, and it all began in the hospital. I’d shut my eyes to try and sleep, but instead of darkness, I’d see images of things. Flashes really. Rivers, strips of land… Places I’d never seen before. At first, I simply thought it was a side effect of the pain killers they gave me, but after I arrived home, and stopped taking the drugs, these glimpses kept happening. It usually occurred early in the morning, after I woke up.

I’d shut my eyes, and instead of darkness, I’d be watching cartoons on an ancient looking television, or see legs (both women with high heels, and men with suit pants) walking back and forth on a sidewalk from the perspective of a toddler. Honestly, even with my astral projection experiences from the past, I thought I was losing my mind, but thankfully my mother, who is my best friend, assured me that I was still rational and quite sane. At the time I thought I might be seeing things from a past life, perhaps as a child.

But my mother, in her infinite wisdom, kept telling me not to place limits on these experiences. I needed to keep an open mind. Perhaps I wasn’t even scratching the surface. She was right… The glim

Hello,

I'm new to the Pimax family by receiving my 8kx yesterday. However, I'm trying to run x-plane and was told Parallel Projection needs to be turned on. But the current pitool doesn't have the option and installing an older version won't recognize the headset. Also, I noticed the backlight brightness slider doesn't do anything (0 to 100 brightness is the same), is this normal for the 8kx?

Thanks for any help!

In search of more FPS, I decided to turn off PP recently and was astounded to find that it doesn't seem to make any visual difference anymore. No more cross-eyed zoom-ins like it used to do a few months ago. All good now in both DCS and IL-2. Haven't tested any other games yet.

And the FPS bump with PP off was significant, like about 20-30% as one would expect. Yay!

Did I miss a memo? Can anybody else confirm the same results? What changed, was it both game devs adopting canted display code, or PiTool, or maybe a SteamVR patch?

NB: I'm on the latest Beta PiTool 1.0.2.087_v2 , but not sure if that matters. 100% Steam SS, 1.0 SS in DCS, 1.0 RQ in Pitool. Edit: Small FOV setting in Artisan, too.

A ticket request to fix the parallel projections requirement for SWS has been posted here:

https://answers.ea.com/t5/Bug-Reports/VR-Double-Vision-and-Incorrect-Rendering-on-HMDs-with-Non/m-p/9549551#M1421

Please add your voice to the post. Probably won't lead to anything but can't hurt to try.

For a polar projection that's equidistant along meridians the equation relating radius on the map to polar angle is

ρ = θ ;

& for one that's equidistant along parallels it's

ρ = sinθ ;

but the case of a projection that's equidistant along a loxodrome - ie a curve of constant bearing (which when plotted on a sphere forms what converges with approach to a pole an exponential spiral around that pole) - a differential equation arises that has difficult behaviour at the origin (letting α be the angle between the loxodrome & a meridian)

dρ/dθ = √((secα)^2 - (tanα.ρcosecθ)^(2))

or

dρ/dθ = secα√(1 - (sinα.ρcosecθ)^(2)) .

If this be 'unwrapped', using a symbolic algebra package (don't even think of trying it by hand!) as a Taylor series, it's found that it converges terribly slowly, & that a very large № of terms has to be used to obtain anywhere-near decent precision. And the fact of there being a 0/0 at the origin is a stumpbling-block to application of the Runge-Kutta method; although it can be to some degree circumvented by starting the iteration at an intermediate value : but obviously the problem with that is that some particular intermediate value must be known in advance!

But the function

ρ(α,θ)

is clearly a natural 'interpolant', or homotopy, between the linear function

ρ(0,θ)

& the sine function

ρ(½π,θ)

; & although there are other functions that interpolate between the sine & either the linear function or some other function (an outstanding example would be the Jacobi elliptic function sn(k,) , which interpolates (or homotopates - whatever the most correct term might be) between sin() & tanh() ), it seems to me that this ρ(α,θ) function is a nicely natural one that might have some treatment of it somewhere by serious geezers, with theorems about it & stuff, & a name for it, etc. And a way of computing it: maybe a series for it in terms of some standard functions - such as maybe Bessel functions, or something like that - that converges with decent rapidity.

Not that anyone would necessarily require a map projection that's equidistant along a particular loxodrome (although I'm not saying definitely that no-one ever would, either!); but the scenario of that map projection might be 'isomorphic' to some other the need of a solution of which has been more compelling.

Is it possible to astral project to a parallel universe? Last night i had this dream where I knew I was asleep but I told myself I wasn’t exactly dreaming either and then when ai found another version of myself I [realized?] I was in a parallel universe. Except as this “dream” went on I began to feel like I didn’t know what was what and eventually forced myself awake.

I’ve astral projected in the past and don’t usually have control over it. It’s usually when I’m pulled to the world where spirits are so that someone I knew who’s passed can give me or someone near me a warning. Is projecting to a parallel existence possible? Has it happened to anyone? Was this just a crazy dream?

This small change in your launch parameters can increase the quality of your HL:Alyx Experience.

The info comes from the NextGenVR channel. (credit)

Here's how you do it:
This simple command line placed inside of HL:Alyx Properties - Set Launch options: -console -vconsole +sc_no_cull 1 +vr_enable_volume_fog 0

Hi, I haven't used my headset in ages so sorry if I missed something but I despite searching I haven't found any info. These options are missing (or at least somewhere I can't find them) in the latest Pitool version. AmI missing something here?

I just wanted to play some Elite and it looks like I need to enable parallel projections.

Thanks!

Seems to me they have made it so it is no longer needed to zoom outside cockpit. Significant performance gain so I now get 26fps rather than 22 ;)

So, I hope I did not messed up the title, English is not my native language.

The problem is this:

Split up a particles r position vector to two components which are parallel and perpendicular to a given n vector unit. For this, I've got that r^(par)= (r·n)n , and r^(per)=r-(r·n)n.

After that, the next problem is to construct the matrix of the linear projection, that creates the component of r parallel to n. This is the part where I stuck. In the solution, basically the following is given (see the picture). I really don't understand how exactly you come up with this sum, and how you can read out the matrix. I've already tried googling, but I couldn't really find anything like that. If anyone could explain me or show me a source so I could understand how is it going on, I would be grateful.

https://preview.redd.it/eeld3gpkmju41.png?width=395&format=png&auto=webp&s=ad0154b8df4331016f4c91ad76f573fa17136cfd

In Steam\config\steamvr.vrsettings you can set:

"steamvr" : { "renderCameraMode" : "raw" }`

the default if you have nothing set is equivalent to:

"steamvr" : { "renderCameraMode" : "parallel" }

You'll need to shut down steamvr before changing it.

This is similar to enabling/disabling parallel projections on the Pimax HMDs.

Many games have shaders that look at the depth buffer axis for things like blending shadows, rendering fog, and more, so using "raw" on them can cause issues.

Be careful: since the canting degree on Index is lower than on Pimax, these issues may be less apparent on certain titles but still may give you a subtle stereo disparity effect.

You may want to search on the r/pimax sub to find out which titles work well without parallel projections and not just trust your eyes (since the canting angle is so much less). Most modern Unreal stuff should be good, except for a shadow blending issue (blending between shadow cascades will be along depth buffer z axis, which will point off in different directions for each eye without parallel projections, they are planning to fix for 4.23).

Treat this as super experimental. Many shaders unfortunately optimize certain things by doing calculations in z space, which without parallel projections ends up being two diverging rays instead of two parallel rays. Since the canting angle is much lower on Index than on Pimax, the performance boost of toggling this is also much lower and may not be worth the hassle of having to restart SteamVR for apps that are and aren't compatible with it and the risk that there is stereo disparity that affects your experience but isn't strong enough for you to be sure about.

(edit: here's an r/pimax thread outlining some that probably won't work with setting "raw", they also link a google docs spreadsheet with a couple parallel projections compatibility columns:

https://www.reddit.com/r/Pimax/comments/bi5ma8/list_of_parallel_projection_titles/ )

FYI

Show that two different parallel lines are either projected onto parallel lines or on two points by a projection pπ,d , where π : Ax + By + Cz + D = 0, d : (x − x0)/p = (y − y0 )/q = (z − z0)/r and π is not parallel to d.

Th pimax team made a post about performance optimisation and RTX2080ti performance I will quote it instead of linking, since there is still some virus concern.

> The team have done some quick comparison test with 50+ games during the holiday on RTX2080Ti, Here are some draft conclusions:

>1. We have achieved ~35% performance improvement by implementing a new rendering algorithm, but it's not backward compatible. it requires Unreal 4.18 or above version, and Oculus SDK 1.17 or above.
But almost every Unity games are OK. That is,
a. New game based Unreal 4.18 or above works perfectly.
b. Old game based Unreal 4.17 or below don't work, and you will get a wrong stereoscopic overlap.
c. Games based Unity engine work perfectly.
d. Games based Oculus SDK 1.17 or above work perfectly.

>To do backward compatibility with the old game based Unreal 4.17 or below, we add a checkbox in the PiTool, but it seems most users turn on the setting but forget to turn off it when playing the new games, thus, they didn't take the advantage of our new rendering algorithm.

>fullsizeoutput_1383.jpeg2846x2008 2.27 MB

>for example:
a. Pavlov VR, Batman: Arkham VR, IL-2 Sturmovik: Battle of Stalingrad;.....
old Unreal engine Not supported
b. Onward, Payday2, DOOM VFR, Skyrim VR, The Gallery - Episode 2: Heart of the Emberstone, Guns'n'Stories: Preface VR,.....
new Unreal version, supported
c. The Lab, The Blu, Fruit NinJa VR......
Unity based games supported

>2. RTX2080Ti VS GTX1080Ti you will get ~30% performance improvement.

>So when you combined solution 1 and solution 2. you can totally get more ~60% performance, taking GTX1080Ti as the benchmark.

>for Pimax 5K+, you can set the rendering quality level 1.5 in PiTool and SS ~100% in SteamVR, The games play smoothly and visual quality looks fanatics.

>For Pimax 8K, you need set the rendering quality level 1.75 in PiTool and SS ~60% in SteamVR, The games play smoothly and visual quality looks fanatics.

>Accordingly, we tuned a special gamma setting for Pimax 8K under 1.75 rendering quality value, it can enhance the sharpness but drop off some brightness.

>important for Pimax 8K, you should set the rendering quality 1.75 in PiTool for good visual quality and sharpness. currently, we don't' recommend any setting blow 1.5 in PiToll. We might lock the 1.5 or 1.75 value in next version PiTool for regul

https://imgur.com/a/cci0bxV

If you aren't sure what to look for to determine whether or not you should be checking "parallel projections" in pitool - here is a simple example. SteamVR Home does require this to be checked to work properly. The above imgur link shows a series of images that demonstrate how objects seem to pop in and out of existence when you rotate your head. This will only happen in this app with parallel projections UNchecked. go back into pitool, check the box, restart steamvr, and it works totally fine as expected.

So - if you aren't sure - move your head around left right. If things are constantly appearing/disappearing near the edge of your vision (note: NEAR, not at or past - obviously things disappear when out of your vision. But they shouldn't just be disappearing when they get close to the edge). - that's a case when you need to check the box in pitool for that game.

I just received my headset and attempted to play Subnautica... after some research I noticed that you have to enable parallel projections, which I did, but it causes terrible screen tearing in the right eye. It doesn't look like this should occur, only a performance drop. Am I missing a step?

Hey All,

So I use a Pimax 5k+ to play Skyrim VR. However, because of the Pimax canted lenses, we need to use a 'parallel projections' hack in Pitool to make it display correctly. Now, this is all well and good, and it works, but it costs around a third of your performance budget. I'd quite like to get that back! And i'm sure other Pimax users would too.

So my question is this. How hard would it be to mod the required configuration changes in on the Skyrim side? I'm potentially willing to have a stab at it my self, if someone can point me in the right direction. Or offer resources if it's beyond my capabilities. I know Devs can and do incorporate this change for a lot of 'live' games, so there is some kind of standard procedure. I don't know how well that marries up with the ins and outs and limitations of Skyrim modding/the old engine. At the least it would be nice to know if this is technically feasible. Anyone with any experience who can offer insight, it would be greatly appreciated.

Also as a point of interest, the new Valve Index has mildly canted lenses.

Thanks.

Valve just published the first of several deep dive articles on their Index HMD and it has the following passage.

> Canted Eye Tubes:

> Second, we canted each lens/display assembly by 5 degrees to optimize inner vs. outer FOV and also improve available interior IPD range. The first benefit of the canted approach is simple: It nudges a few more degrees of FOV towards the outer sides, at the expense of the inner sides of each eye where stereo overlap is at play. Stereo overlap is still vitally important, of course. The canting simply provides a way to keep angular resolution of the system high while still striving for the higher overall binocular FOV that we were hoping to provide.

> The main downside of canting is that both the existing software content library and the field of GPU rendering hardware are all typically optimized for parallel eyes. Fortunately, this may be readily compensated for in software using the re-projection techniques we already depend on for maintaining a constant frame rate. We just need to do a tiny bit every frame.... This way, apps past, present, and future may continue rendering in parallel as they always have, and they will "just work" for HMDs with mild amounts of cant angles.

I wonder if Pimax could benefit from this as well instead of using their demanding "parallel projection" algorithm?

https://np.reddit.com/r/ValveIndex/comments/c47pi3/index_rendered_fov_measurements/esf836e/

Would need someone with more time to look at it a bit closer and see why the Pimax parallel projection matrix requires more unused FOV that gets cropped and hopefully masked out than the does the Index.

There may be some ways of applying some skew without making z direction non-parallel that Pimax is missing. Someone needs to look closer at the raw matrices.

If you want to change Index into non-parallel mode set

 Steam/config/steamvr.vrsettings

 "steamvr": { "renderCameraMode": "raw"}

Today i have found a thread in the Steam Forums that could be a possible workaround for the Resolution Limit in SteamVR for people that uses Parallel Projections and experience Bluriness. I can't confirm this by myself because i don't have a Pimax. But somebody can try this.

1. Close SteamVR and Pitool if it's running
2. Head over to X:\Program Files (x86)\Steam\steamapps\common\SteamVR\resources\settings and open the file "default.vrsettings" in Wordpad or Notepad++ or whatever.
3. In that file look for that entry -> "maxRecommendedResolution" : 4096,
4. Change the "4096," to "8192,"
5. Save the File.
6. Change the SuperSampling Value in SteamVR and Pitool, to your desire.
7. Try out and see if it makes a difference.

I hope this could help. Can somebody confirm if it's working?

Greetings

The performance impact is so terrible that I'd like to avoid it as much as possible, but I'm still unsure which games require it.

I assume that if everyone tested just one game we could all pull together and have a complete list in no time.

Alternately, I read somewhere that it's older versions of Unreal engine that have this problem so maybe there's a list of games with which version of unreal engine it's using so I can figure out which games need it that way?

Makes no sense they're literally the same engine and game but different modes (1st is single player story mode, second is a multiplayer game mode). Both oculus exclusives btw. Such a shame since echo arena has been my #1 game to play for two years now but now with having to turn PP on, it's really unplayable because of how bad performance gets..can't even use large FOV on it cause it crashes with PP on.

Is this not fixable from Pimax's side since lone echo works fine? what's the cause of this?