Parallel Projection Puns

This instagram page (link below) proclaims to be "reimagining rock'n'roll history via projections from a parallel universe in which REM chose instead to call themselves Cans Of Piss" and is probably essential content for all like-minded REM obsessives

It's actually really nicely executed too, the albums are being done in chronological order

https://instagram.com/cansofpissofficial

Enjoy!

In many games, such as MSFS, PP is needed in the 8kx and is a huge drain on performance.

I saw no mention of PP in the Frontier event. Will it still be needed, or does the new display, software or eye tracking etc, mean PP will be a thing of the past?

Thanks.

Hello there! So, I just received my Pimax 5k+ and apparently I did NOT do enough research before buying. I like it, a lot. Some games work simply flawlessly, or nearly so, a few others, however, not so much.

I assume the Knuckles tracking problem can truly only be solved with an additional USB dongle, correct? If so, any advice on where to find one so I can play Beat Saber and a few other games I've had some problems with would be great.

Is there ANY substantial work around for Elife Dangerous and parallel projection? The fov is simply astounding and I'd rather not keep my Index plugged into my PC JUST to play Elite ( I haven't even tested if I can do that). I bought the Pimax for Elite, especially and for whatever reason, none of the parallel projection issues came up in all of my searches prior to my purchase.

Even with a 3090 and a 3700X, I can barely clear 30 fps with all SS at 1.0, Steam resolution af 100% instead of the recommended 150%-- I mean, am I better off just cranking up the Steam resolution on my Index for Elite and forgoing the Pimax altogether, or should I just... find newer games to play and abandon VR for one of my favorite games, now?

Sorry if this sounds like a fair bit of whinging, but I like to have my cake and eat it whenever I can lol.

Thanks!

When I first got my 8kx I read up as much as could on what settings people recommend and so on. I read up that Parallel Projection was a very demanding setting and it was best to leave it off unless you were seeing lots of clipping on objects/UI/etc near the edges of your view. I do see that in a few games I play but it doesn't bother me, at least not at the expense of 35%+ FPS performance drop.

But then I was playing one of my favorite VR games currently and noticed the cat at the main menu looked really weird and it was bugging my eyes to focus on it. It wasn't until I closed one eye and looked at the cat, then closed the other and look to see that the shadows on the cat were flipping based off which eye I was looking through. With my left eye open, the shadows would be on the right side of the cat (which is correct based off the main light source), but looking only through my right eye the shadows were on the left side of the cat. And with both eyes opened, my brain was trying to combine the shadows.

So I said what the hell and let's try turning on this PP setting and see if it helps. Poof. The shadow problem went away and the image was displayed correctly (yes, as well as the outer edge clipping issue). Luckily the game is pretty well optimized and everything still runs very smooth with PP on.

https://preview.redd.it/pghlgtoq9eb71.jpg?width=744&format=pjpg&auto=webp&s=978987bf24d34dc633763942885356ad82282b41

This is a Unity based game and I was told most Unity games just work with Pimax so far. Or it's easy to fix the issues.

https://preview.redd.it/jal1ugtwbeb71.jpg?width=831&format=pjpg&auto=webp&s=796764c3a44985ef9cc334f9c24f9d9322b84566

I notified the dev, but they haven't heard of any specific setting in Unity to account for this weird shadow flipping issue seen only in Pimax HMDs (I've played this game on Rift CV1/Quest 1&2/Index/VP2 as well).

Another game I've started playing recently is the VR modded version of Valheim, which is great. But this shadow flipping issue popped up again in that game as well. I see it mainly on treasure chests in the game. With the shadows appearing on the left or right side of the chest depending on which eye you're looking through. However Valheim doesn't show up on the official games tab so I had to manually add it. Though even with turning on that PP setting for Valheim in PiTool, it doesn't seem to be doing anything. Hard to tell if it's because I'm manually adding games to the

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

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?

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.

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.

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

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.

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

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.

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!

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?

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 ;)

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/ )

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

FYI

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.

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