About same camera FOV value has different results in single screen mode and VR mode

Unity Engine
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It seems in stereoscopic mode, that is after XR plugin is initiated, the camera FOV will act differently in play mode.
For example, say, the default VR helmet’s FOV is 100, and the camera FOV hence is set to 100, the result when rendering in XR mode/stereoscopic mode will look much closer than 100, as if the FOV value is 60-70.

When turning of XR, when it becomes common single screen rendering mode. The FOV will be looking familiar again.

And the problem is, when doing LOD group switch threshold ratio calculation, it seems Unity is using single screen mode’s screen space, which makes it looks it switches at a much closer distance in VR mode. This makes me hard to calculate the actual LOD bias and LOD ratio I should use.

Can anyone confirm and give some opinions, please?

2

I have stumbled upon this thread where LOD VR Bias calculation was discussed.
As so it seems, Unity Technologies team itself created an equation “to determine a correct equation that will give anyone a correct bias value for cameras with mismatched FOVs” (quoted from there)

Take a look : https://discussions.unity.com/t/654767

Hope it helps!

1 Like
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Yes I am using a similar bias number, just still, the lodgroup’s ratio is not super intuitive, guess just have to do more tests in the actual platform.

That thread proves the number. Thank you for introducing it.

btw, even the single camera’s 9x fov feels apparently different from the vr platform’s 9x fov. So I guess try it in actual platform is a must do way.