just bought the dev kit (can you blame me?) have some q's

[zella]

Hey guys,

firstly would like to say how glad i am to have found this forum, just saw palmers ces interview which lead me here.
there are some other very officially named forums, that are almost exclusively populated by clowns who pretend to know what they are talking about. I don't know what im talking about, i dont really have a clue, so thats why im here. and appologies if i have said anything stupid, or something that has been asked a million times, but i havent yet found an answer.

So...only just found out about the rift recently, then i saw some reactions of the press at ces, and i was sold, bought one immediately.

so my question (i have read the faq, but sill have a concrete technical answer)

why cant the rift be used for regular applications as a normal monitor, and in particular games. (as i understand that you dont want your entire FOV taken up by ms word or something.)

I know that without proper support you wont ever get the VR part, but why cant you just use it as a huge stereo display for regular games? surely its a very simple job to post process an image and correct for the lens distortion. and i know that a main part of the SDK is going to be dealing with that issue.
and i realise that for things like in game video etc it wont work well/if at all. but i would just be satisfied to walk on the beach in crysis.
i have heard that lack of head tracking will cause motion sickness that will make it unplayable, but to be honest i will be the judge of that. my $700 3d monitor is unplayable in my opinion, i have used it maybe a dozen times. surely this can work as a 3d display for older games?

so are we going to see lots of support for games (especially UE3 games) once the dev kits ship. or is it not such a simple task of post processing and image, resizing, adjust for lens distortion etc. is the fov so large that the game engine has to render more stuff?

thanks guys

[yuriythebest]

Welcome to the forums!

why cant the rift be used for regular applications as a normal monitor

well, considering the Developer version is 1280x800 split between 2 eyes, would you really want that?

and in particular games

for the game to display correctly on the rift, 2 views (for the left and right eye) must be generated and having them pre-warped to correct for the optics. This can be either accomplished natively or by a program that hacks into the DirectX and creates these 2 views ( check the Vireio Perception forum), additionally there's the matter of controlling your view - 2 axis like your mouse is not enough for a quality VR experience

I know that without proper support you wont ever get the VR part, but why cant you just use it as a huge stereo display for regular games? surely its a very simple job to post process an image and correct for the lens distortion. and i know that a main part of the SDK is going to be dealing with that issue.

that would be cool

so are we going to see lots of support for games (especially UE3 games) once the dev kits ship.

check the list here:
http://en.wikipedia.org/wiki/Oculus_Rift

or is it not such a simple task of post processing and image, resizing, adjust for lens distortion etc. is the fov so large that the game engine has to render more stuff?

short answer, it varies. it's one thing to get "something" to display on your screen, but if a game wasn't designed for VR or Stereoscopic 3D in mind, you may encounter visual anomalies.
http://www.mtbs3d.com/index.php?option= ... &Itemid=94

[neverman]

Welcome!

[zella]

great, thanks for your answers.

so im pretty happy then. i would have been content with just a few tech demos, doom and hawken. but from what i can tell the mod comunity/and some majors will get busy when the dev kits ship, and there will be plenty to do before consumer release. basically i couldent wait until summer 2014. i know that im gonna have to organise some kind of rota among my friends to try this thing out.

and i hope someone is going to make my stroll down a korean beach a reality!!

[2EyeGuy]

there are some other very officially named forums, that are almost exclusively populated by clowns who pretend to know what they are talking about.

Yes. It helps keep the clowns away from here though, and maintains the much more intellectual atmosphere here, so maybe that's a good thing. But I think they shouldn't have used quite such official sounding URLs for their fan forum.

why cant the rift be used for regular applications as a normal monitor, and in particular games. (as i understand that you dont want your entire FOV taken up by ms word or something.)

Firstly, the main reason you can't just plug the Rift into any HDMI/DVI device, is that the Rift has a single 16:10 screen which is divided down the middle so the left eye sees the left half and the right eye sees the right half. So it would be completely unreadable or unwatchable. Also the lenses over each eye warp each half of the image by stretching out the corners like a pincushion.

It would be possible to have extra processing chips inside the Rift control box that take a normal signal and turn it into a side-by-side image so each eye is seeing the same thing (which is slightly more complicated on the 7" Rift because it isn't 100% overlap, but still possible). And have processing for correcting the lens distortion. But Oculus don't want that because they are trying to make the signal processing as simple as possible to keep down latency, and because they are aiming for a much cheaper price-point than other VR HMDs. They also want to keep the design simple, so there's less room for things to go wrong. Also they want it to be able to run on just the power from the ports, so they can't add any processing that's too power hungry, and they don't want to generate too much extra heat and have to add fans to the control box.

But even if they did add the extra processing in the control box to make it side-by-side and warped, that still leaves the problem of the aspect ratio being wrong. The Rift is taller than it is wide, since each eye has an 8:10 aspect ratio (aka 4:5 or 16:20). So if the input signal was 16:9, you wouldn't want it stretched vertically to more than twice as tall (16:20). They could fix that by making the processing letterbox the signal.

Another problem is, the lenses in the Rift make the screen appear huge, so it takes up more than 90 degrees of your view. That's like having a 200 inch screen in your lounge room. A 90 degree FOV is best for content that's filmed with a 90 degree super wide-angle camera lens, or from a camera that's far away. You don't want the action, or close-ups of people's faces, to be in your peripheral vision. You want the action to be in the middle of the screen and have peripheral background scenery in your peripheral vision. But because TV shows are designed for TVs that take up maybe 30 degrees of your FOV, and movie screens that take up about 45 degrees, they look bad stretched out over your whole vision. But it would be good for PC games, where a game FOV of 90 is common, and OK for console games where an FOV of 60-70 is common. You'd need a button to make it only use the middle part of the screen for watching movies or TV.

The Oculus Rift uses a 720p HD screen (except 800p vertically because it's 16:10 not 16:9), not a Full-HD screen, and it's split between each eye, so the resolution is roughly 640x800 overall (it's complicated because it's more since it's not 100% overlap, and less since you can't see the corners which are stretched out). If you waste most of the resolution by only using the middle 45 degrees of the screen, and you letterbox it to 16:9, then you are left with a resolution of a bit more than 320x180 for watching a movie in. Actually it's not quite that bad since the pixels aren't distributed evenly by the lenses, so 45 degrees actually has more than half the pixels. Lets say, 400x225. I used to play games in resolutions lower than that (almost all DOS games are 320x200), and it's not bad, but it's lower than people are used to.

But there's still another problem... The screen is attached to your head, and you can't see anything else except the screen. When you turn your head, what you are looking at turns with you, instead of staying still where it's supposed to. That triggers your body's automatic instinct to vomit up the magic mushrooms it thinks you must have eaten because when we evolved that only happened when we ate something hallucinogenic and likely poisonous. The same thing also happens the other way... if the game's or movie's camera is moving around or turning quickly, and your head isn't, you will also feel motion-sick and want to vomit. The smaller the FOV of the screen, and the more you can see the outside world, the less of a problem that is. But for the Rift it would be a significant problem.

Ironically, if Oculus make their product strictly better by adding extra features like that, it would actually get worse reviews and worse consumer response. If someone would pay $300 for a device that does A really well, then they won't pay $400 or even $300 for a strictly better device that does A really well and can also do B not very well. They'd only pay $200 for that better device, because they would perceive it as worse. That is sometimes hard for me to grasp, since my instinct is to always try to make things slightly better by adding mediocre features.

That's why it doesn't work like a normal DVI/HDMI monitor that you just plug into any HDMI/DVI device and watch. So the next question is, why can't it just work on a normal Windows PC in any Windows program? That wouldn't need any changes to the hardware, just some software or drivers to make it work.

Palmer, Dycus, and the other Oculus people aren't software guys. They work with hardware. So this isn't their area of expertise. With the developer kit they are just trying to get their hardware out to software developers so they can see what amazing things software developers can do with their hardware. Except for integrating into UDK and Unity and proving an SDK with examples for how to make games for it, they are letting other people worry about that side of things.

Some people have started working on that problem. Nthusim are making a special version called Nthusim HMD edition, that works in any program (Internet explorer, Microsoft Word, games, etc.) and also the windows desktop, that will render the screen as two side-by-side barrel-warped images so that it looks correct on the Rift. It won't make it 3D, and it won't add head tracking, but you'll be able to use normal programs. It will cost money, I don't know how much. I'm not sure how they're going to deal with the aspect ratio or the huge FOV, but it shouldn't be hard for them to make options to only use part of the screen, it is their area of expertise.

There's also a free program on here called Warp Injector that can do the same thing for just most Direct3D games, but not for other windows applications.

Since they have no head-tracking, that doesn't deal with the problem of motion sickness though.

Other people are working on just the head tracking problem, with programs like FreePIE or GlovePIE. They could be used in conjunction with other programs like nthusim HMD.

For watching movies, other people are working on a virtual cinema approach. That way it looks just like you are inside a real cinema with a big screen at one end with the movie playing on it. It would even work with 3D movies. It would have head tracking, and most of the view would stay fixed when you turn your head rather than following you, so it wouldn't make you motion sick. It still has the problem of low resolution (I don't know if head-tracking improves that), but I guess you could choose how close to the screen you want to sit to choose how much of the view the screen takes up.

For playing existing games that don't natively support the Rift, a couple of people are working on special 3D drivers for them. They will support head-tracking with mouse emulation and Direct3D hacking (for roll), and the warping, aspect ratio, and FOV fixes. Cybereality is working on the free Vireio Perception driver, but it only supports a few games right now. Someone else (was it MaterialDefender?) is working on the VorpX drivers which support a lot more games and render 3D faster, but cost money and use a form of 3D that isn't quite as accurate. VorpX might also support the warping and side-by-side in normal windows applications just like nthusim HMD.

That's not perfect, since there are bugs, and since the games weren't originally designed for the Rift and have HUDs, cutscenes, and head-shaking effects that don't work well with the Rift. But it will allow people to play existing games on their Rifts.

Ideally, people will still want games designed specially for the Rift or games that support the Rift natively. Since they will work perfectly without issues, and will make you feel like you are actually there.

my $700 3d monitor is unplayable in my opinion, i have used it maybe a dozen times.

Why?

A few things that will be better with the Rift compared to a 3D screen are:
Zero ghosting. Normally every other 3D screen has some ghosting where each eye can partly see the image from the other eye. HMDs (except the HeadPlay) don't have that issue, since each eye has it's own screen that's completely separate.
It still works when you roll your head. Normally tilting your head completely destroys the 3D effect or feels weird because they expect your eyes to stay separated only in the horizontal direction. That can't happen on a HMD.
If they get position tracking working, or even just the head and neck rotation model, then moving your head side to side won't have the strange effect that things popping out of the screen are moving side to side.
For objects far away (which is most objects), your focus will be almost correct and match your eyes convergence. On a 3D monitor you have to focus on something close while looking far away.
The sides of the screen won't occlude objects that are supposed to be in front of the screen as much, since the sides of the screen are much further out in your peripheral vision.
It won't seem gimmicky. Things won't seem like they're popping out of a screen (it's like there is no screen), they will just seem like the 3D in real life. This can be a bad thing though for people who like gimmicky 3D (I admit that I do), and those people might prefer Augmented Reality rather than Virtual Reality.
The dimensions will all be exactly correct. Normally 3D looks different depending on how far away you sit or how big your screen is. So the depth doesn't match up to any real world distances, and doesn't behave consistently with the laws of geometry and perspective. It can also sometimes diverge your eyes past infinity. But with the Oculus Rift you don't have to worry about that, everything can be rendered at exactly the real life distances with 3D to match.
There's no loss of brightness with the 3D in the Rift.
There's no flickering like with 3D projectors or active shutter glasses.
There's no colour distortion.

surely this can work as a 3d display for older games?

So far people have been focused on only getting it working in games from the past 10 years (DirectX 9 and above). But I'm personally going to try and come up with ways of getting it to work with games older than that. I'll probably make a DirectX 8 driver at least.

so are we going to see lots of support for games (especially UE3 games) once the dev kits ship.

Yes, I'm sure we will a few months after the dev kit ships. It still takes a little bit of time to get things working or to get things released.

or is it not such a simple task of post processing and image, resizing, adjust for lens distortion etc.

That part's probably fairly simple, especially since Oculus will be supplying code to do all that. But don't forget the other parts, like head-tracking, getting the HUD to work OK in VR, and having less screen-shaking and cutscenes. It's still not too hard, but takes a bit of time. Also if the scales don't match up, people will suddenly notice that. Games often use different or unrealistic scales for different kinds of objects. And the gun is usually rendered a special way that's not part of the normal 3D world, so it looks right in 2D and so it doesn't go through walls. In VR you have to render the gun so it seems like part of the world. Also, cross-hairs don't work the normal way in 3D.

is the fov so large that the game engine has to render more stuff?

Vertically it certainly is. Horizontally it's only slightly wider than older games normally render (they render 90 degrees but they show it in about 30 degrees of your vision, so it's not realistic). Console-ports will be rendering more stuff, since they had lower FOVs to start with.
But they are also now rendering everything twice, once for each eye.
And if they can't do it at a constant 60Hz, it will feel weird and make you slightly motion sick when you turn your head.
Valve will be talking about all these issues in their talk at GDC, when they discuss how they ported Team Fortress 2 to the Oculus Rift.

thanks guys

That's OK. Although it took longer to answer than I expected. You did ask for technical details and explanations.

[KBK]

Excellent post. Thanks for putting in the effort.

[zella]

Hey man. Firstly than you, I really appreciate you taking the time to compose that rep¬ly¬.
And I absolutely wanted a technical answer, so great.

Lol at the fan forum, that’s exactly what it is.

Yeah I have heard palmer saying that all they want to do is push pixels to the screen with the control box. I wasn’t really expecting anything else. I was more thinking about using the grunt of my rig for that.

Ok I get it, so some games it is just a case of adjusting for the lens distortion, but others simply don’t have the proper FOV, and will require more work.

I probably haven’t been looking hard enough, but you seem like a willing teacher. Could you please explain overlap? Is it something to do with that middle part of our vision that is serviced by both eyes?

And I really dig the hallucination and nausea thing. I’m a firm believer that everything in our complicated modern lives that’s related to human behaviour can be explained with some caveman logic.

Glad to hear so many good ppl are working on solutions. I will be sure to check out Nthusim HMD, warp injector, etc.

Also like the idea of a virtual cinema.

I heard palmer saying that 3D drivers aren’t going to be very relevant for the rift for quite a while. I know for the purpose of converting old games without access to the engine code they are vital.

Again good to hear about Vireio Perception and the vorp x solution.

And yeah I know head bob, HUD, and automatic/cinematic camera control will be a problem. But I’m willing to set the bar a lot lower for those experiences. There are just some in game environment that I would love to jump inside, even if I can’t play the game to its full potential

On to my monitor. First I bought it in England, for £410 pretty much the day it came out, you would almost certainly not pay $700 in the states, that just a straight cash conversion (we get royally ripped off over here).
It was one of the first, if not the first to have dual link DVI and hdmi 1.4 so that meant I could use my PC and PS3 for 3D. I then found out that console 3D is a laughable joke (as are consoles in general).
And PC 3D is no good for me either, maybe it’s the monitor, it’s not top of the line (Acer gn245hq) but what it adds to the experience it also takes away. 3d in movies is fine, because movies aren’t that high quality if you ask me. Pause an hd film, and look at that still image, it’s not that great, 24FPS and if anyone is moving across shot its probably blurry, so adding 3d doesn’t take much away in terms of fidelity, it just adds immersion.
No when you look at a still from my PC (60fps) , its crystal. The clarity is unbelievable. And when I put the 3d on it takes away some of that clarity and sharpness, and the immersion it adds doesn’t make up for the loss. The only game I have played on it recently is the walking dead, as the graphics are pants anyways, so it does add to the experience.
I wish I had just put the money towards a 30in 2560 monitor instead.

Great to hear that there will be more things to do than just the tech demos and a few games, relatively soon after release.
And yeah I know about the crosshairs issue (NVidia’s laser pointer does a good job of fixing that)

[laast]

That's not perfect, since there are bugs, and since the games weren't originally designed for the Rift and have HUDs, cutscenes, and head-shaking effects that don't work well with the Rift. But it will allow people to play existing games on their Rifts.

About Shaders at wrong deph in some DX9 games: is someone in touch with Helix, a 3D fix "master" for 3Dvison users (http://helixmod.blogspot.fr/)? Mixing his dx fixes with VIREio could provide us perfect 3D rendering.

[2EyeGuy]

I probably haven’t been looking hard enough, but you seem like a willing teacher. Could you please explain overlap? Is it something to do with that middle part of our vision that is serviced by both eyes?

Yes. Here's Randomoneh's diagram, I haven't checked if it's to scale:

The picture of a duck isn't the best example since it is showing a very low FOV, and really we are talking about high FOV pictures. The circle represents more than 100 degrees of your vision, and that duck would have to be metres away for that image to be accurate. So it will seem a lot more natural than that image. But that diagram shows how it works.

Partial overlap is how your eyes naturally work, if you look at something distant then close one eye, you'll see part of that image disappear. That part could only be seen by one eye, and therefore wasn't in 3D. But on the Oculus Rift Dev Kit the overlapped area is smaller than it should be in real life.

I think the overlap will be even lower for close objects.

One advantage of partial overlap you can see from that image is that the aspect ratio is now better. Which means you'll get a wider horizontal field of view than you would have before. But they haven't told us the numbers yet.

In the original Oculus Rift design with 5.6" screens, the centre of each eye was roughly over the centre of it's screen half. When they discovered there weren't enough of the 5.6" screens available, since they weren't being made any more, to cover the amount of people who ordered a Rift, they had to look for a different screen. They found a 7" screen with much better pixel fill so you didn't get the screen door effect (black lines between all the pixels), and much lower pixel change time so you didn't get motion blur when you turn your head.

But the 7" screen is bigger, and the distance between people's eyes is still the same, so the eyes aren't over the centre of each screen half any more.

[GeraldT]

@2EyeGuy

Just to be sure I understand this right ... you are not saying that part of the picture on the screen will be overlayed right?

And you have given me something to think about with the 7" change. I am really curious if in the end the experience might still be inferior to the 5.6" version due to too many pixel lost in the border areas. They still used the older version for demos!

[zacherynuk]

Post of the year. (Damn it - one post up I mean )

[oculusfan]

I'm sure if the extra screen area is detrimental, they could easily populate a 5.6" image and surround the remaining screen space with black borders. Then they would have the exact same output that the 5.6" screen was giving except with all the benefits of the better display.

[KBK]

My IPD is, apparently, 7.1cm, so the 7" will work OK for me, from what I understand of the subject.

[2EyeGuy]

I'm sure if the extra screen area is detrimental, they could easily populate a 5.6" image and surround the remaining screen space with black borders. Then they would have the exact same output that the 5.6" screen was giving except with all the benefits of the better display.

Except lower resolution.
BTW, I don't know if they use the same lenses with the 7" that they used in the 5.6". If they use less powerful magnification then there will be less screen-space on the nose side of each eye.

My IPD is, apparently, 7.1cm, so the 7" will work OK for me, from what I understand of the subject.

Mine's only 6.25cm. I'm not saying the IPD of the Rift Dev Kit is fixed at 7cm. That's just a number Randomoneh used for that diagram. A lower IPD means less overlap and a wider total FOV. The average IPD for men in the US army is 6.5cm, and 6.2cm for women. So it's unlikely the device would assume an IPD of 7cm. Since it's a sausage-fest here (see the poll) with only a few women developers, they'll probably assume an IPD of 6.5cm for the dev kit. They may or may not make the lenses adjustable to suit a range of IPDs. Software will probably have to support a range of IPDs though. The consumer version will probably have adjustable IPD to accommodate women, children, and people with different IPDs.

[zella]

Thanks 2EyeGuy. I get it now.

and GeraldT,

They still used the older version for demos!

This is a very interesting point. I think, and hope, that it was for the legitimate reasons they gave, which was: the old prototype was more functional than the dev kit, as they had mockups of the dev kit lying around at CES.
It would be very disappointing, not to mention totally deceitful, if the 7in dev kits were working as stably as the old version, but they chose not to use it as it gave a worse experience.

They strike me as a transparent bunch. And they were all saying the experience with the new screen was better. maybe overlap is worse, but its made up for by the better switching time and fill rate?

[GeraldT]

That is just the point - I have never heard anyone saying the experience with the new one was better. They only mentioned the new one when someone complained about the blur or the screendoor, and then they were saying that those two aspects are gonna be better with the new model. I can't remember a "the experience will be superior with the new one".

So I went back and had a look at the blog:

"... in the end it should result in an improved Oculus Rift developer kit and a better VR experience overall."

That leaves room for interpretation.

And yes I do like the whole Oculus crew and I do believe they are quite open so far. But I can not remember Palmer mentioning a blur or screendoor in the kickstarter video. So it is not as if they try to advertise the downsides.

I will still be happy with the Rift if I have to make some tradeoffs in pixel-density - this is a very cheap device and I don't mind them making adjustments to the design as needed. I am still curious about what I will get though!

[2EyeGuy]

That is just the point - I have never heard anyone saying the experience with the new one was better. They only mentioned the new one when someone complained about the blur or the screendoor, and then they were saying that those two aspects are gonna be better with the new model. I can't remember a "the experience will be superior with the new one".

So I went back and had a look at the blog:

"... in the end it should result in an improved Oculus Rift developer kit and a better VR experience overall."

That leaves room for interpretation.

And yes I do like the whole Oculus crew and I do believe they are quite open so far. But I can not remember Palmer mentioning a blur or screendoor in the kickstarter video. So it is not as if they try to advertise the downsides.

I will still be happy with the Rift if I have to make some tradeoffs in pixel-density - this is a very cheap device and I don't mind them making adjustments to the design as needed. I am still curious about what I will get though!

I think the Kickstarter video was more about the consumer version. The developer kits were just the first step they needed to get that dream happening.

Now is when Oculus have access to the final 7" dev kits to test and work with, so we'll probably start seeing more information about them soon. But they'll be in our own hands sooner than we think. It's already a few days into February, so not long now until the first people start getting them. I expect the experience will be amazing. But if, for some reason, the 7" displays turn out not to be as good a choice, I'm sure they'll fix it in the consumer version. Half the point of the dev kit was to get developer feedback on what works well and what doesn't.

[KBK]

well, I did read a bit about better CR, better fill rates, and 24bit (3x8) color depth, and a panel that is about twice as fast.

Which means the basic display itself is better than the original unit.

(from the Oculus blog) (and Nate speaking in a few interviews)(Nate is REALLY good, as a front man, BTW.)

Thus, except for potential IPD vs lens problems, I see no reason why the newer version is not to be better.

As well, it is possible that the mock up at the show (CES) was a printed example. Then a mold, then cast a new one, in black, or do a black print from the get-go.