Discussion Real mirror achieved by camera manipulation?

I was wondering have anyone tried using mirrored camera to make a real mirror.
I've seen a few uses static camera and render texture to "try" to make a mirror but those aren't real mirrors.
Also, is it worth it to do it this way? or reflection probe is just better?

 

They're as real as any mirror in a game that doesn't use expensive raytracing.

Reflection probes generally make the most sense if you're dealing with multiple reflective surfaces and still use fundamentally similar processes to the render texture idea.

 

https://forum.unity.com/threads/planar-reflection-mirror-legacy-renderer-vr-compatible.1170721/
https://forum.unity.com/threads/vr-mirror-test-project.1219659/

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Proper mirror requires you to render your scene twice.
And if you're doing it in VR, then you'll be rendering it three times.

If you're not in VR but in flatscreen game, you can achieve mirror effect using camera stacking and matrix overrides.
If you're in VR, you can no longer do that, because some of the required functionality is broken.

 

What I meant was those mirror won't look right on other angles except direct front.
And I think by manipulating the mirrored camera you can make a REAL working mirror.

Let me put it this way:
a single mirrored camera onto a render texture on a quad VS a same size reflection probe surface
which will run better?

 

If you're talking about cubemap reflection probe, t hen it will perform and look worse than a mirrored quad on a flat surface.

If you're talking about HDRP planar reflection probe, it should largely be the same, but in VR it might not be aligned perfectly if you try to poke finger into the mirror (which is why I bothered with the project above).

Unless you're running a raytraced environment, mirrors are expensive, regardless of what you do.