Can I render one billboard per eye for a VR stereo effect?

Development Platform & Builds XR Development
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1

Hello,

I’m making a VR experience on rails and thought it would be fun to have a stereo video (on billboards) at one part. Is it possible to send one billboard to the left eye and one to the right?

Thank you!

2

It was possible to do this in 4.2 by reading the values set in the ViewToClip matrix. Doesn’t work in 4.3. Has anyone managed this yet?

3

Finally got there. All you really need to do is:

  1. drag out a ‘screen position’ node in your shader.

  2. Break out the X coordinate and test if it is over 0.5.

  3. If it is: it’s the right camera. If not : it’s the left camera.

4

This is super helpful. Thank you so much!!

5

Could someone expand on this?
I need a way to create a 3D portal or Mirror effect in VR… Basically a SceneCapture2D, that sends a separate feed for each eye.
Could I create 2 cameras, at the distance apart of the player IPD, each sending to it’s own render texture, then display only the appropriate eye on a material?

Not exactly sure how to use “Screen Position” in order to accomplish that… :confused: Like how do you get the material to tell if the coordinates are over/under 0.5? I have no idea how to do that kind of logic in a material. heh

6

Anybody found out how this works for the HTC Vive?

7

Hello,

if you want to have dedicated access to the rendered images for left and right eye using the “ScreenPosition” node in Unreal Engine 4.x you must turn off “Project Settings → Rendering → VR → Instance Stereo”.

At least I can confirm this with HTC Vive and Unreal Engine 4.14.3. “Instanced Stereo” was introduced in Unreal Engine 4.11 and increases the performance tremendously.

Any ideas how to avoid to turn off “Instanced Stereo” are welcomed.

Best,