3

In my experiment, I find this problem in cardboard sdk in unity. This problem exists in a lot of apps. In my opinion, the right scene and left scene should exchange.Cardboard demo Cardboard Demo and Jount VR also have this problem( just like this image, I think the right eye should see the left part), I will feel uncomfortable in this situation. Could someone explain it for me?

Dobbie
  • 133
  • 1
  • 10
  • Found more info on this? I'm surprised how a very few people are interested why they made it like this. Most of the comments I found is that it is a bug and should be swapped but it clearly is not since you can see 3D without any struggle. – KwahuNashoba Apr 18 '17 at 13:02

4 Answers4

1

I think it may be my misinterpretation, but I don't know if my idea is correct. For example, when we see something near before us, our left eye will turn to right direction and our right eye will turn to left direction. It's a littel like cross eyes. So it will get the result in vr app. The right eye can see more in left direction and the left eye can see more in right direction. This may be what google engineer thinking about. If anyone has some ideas about it, please contact me!

Dobbie
  • 133
  • 1
  • 10
1

I came up with my own theory about this. Maybe it will sound reasonable to you.

If you look at VR camera structure from top view in Unity (having both left and right camera selected) you can notice that they are offset-ed from the center (left eye camera left from central axis and right eye camera right) but are also tilted towards some imaginary point on central axis that is very close to them. This position and orientation is natural for our eyes when we try to focus something close in front of our nose. You can see that more of the left part of the scene fits in the right camera's frustum and vice versa.

This makes sense even when we focus something at larger distance. In theory, if you look at some point in infinity, "rays" from your eyes will be parallel and in that case your left eye will indeed see more left and right eye more right. But, you always focus on something that lays on axis going straight through the middle of your head so left eye will always see more right and vice versa.

gVR stereo camera

KwahuNashoba
  • 244
  • 3
  • 13
0

The most common reason for incorrect parallax in Cardboard apps is actually due to the phone. Many phones seem to report an incorrect DPI value. Cardboard uses DPI to determine the size of the screen, so an incorrect value throws off the screen size value, which then leads to a wrong inter-pupillary distance.

However, even when the DPI is correct, you should expect to see a bit more of the left side of the scene in the right eye, and vice versa for the left eye. This is just due to asymmetry of the viewing angles. Most viewer lenses are slightly farther apart than the center pixels of their corresponding screen half, which causes the field of view to extend a bit farther on the inside angle (towards the center line) than it does on the outside angle (towards the edge of the screen. (Try this looking through a small window. If you move a bit off center to the right, you can see a bit farther to the left through the window, and vice versa.)

smd
  • 829
  • 2
  • 6
  • 7
  • Thank you for your detailed answer! But I don't think it's the point. I have tried it in a lot of mobile phones. It's clearly the right part and left part are reversed. – Dobbie Feb 21 '16 at 10:57
0

I had this problem and was able to fix it by calibrating my phone's magnetic sensors. I have a Samsung Galaxy S7 and here's how to do it on that phone: https://www.youtube.com/watch?v=qRhaUznKbLg

Hope this helps, even if I'm a year late :-)

/Emil

emilast
  • 559
  • 1
  • 5
  • 11