Logarithmic depthbuffer not working correctly on devices that do not support EXT_frag_depth

[Avocher]

Description of the problem

Surfaces "bend" and disappear after the latest update to support logarithmic depthbuffer on devices that do not support EXT_frag_depth with logarithmicDepthBuffer set to true.

https://jsfiddle.net/dz37428b/7/

Three.js version

• Dev
• r89
• ...

Browser

• All of them
• Chrome
• Firefox
• Internet Explorer

OS

• All of them
• Windows
• macOS
• Linux
• Android
• iOS

[WestLangley]

Surfaces "bend" and disappear

Can you provide a screenshot?

after the latest update to support logarithmic depthbuffer

What "update" are your referring to? Did it work prior to that update?

Chrome

Chrome only?

[Avocher]

Here's a screenshot from the fiddle

I'm guessing it indirectly happened after this pull request #11995

I only had chrome/safari on my test devices so i checked those, I can install firefox if you want.

I should probable add that, the closer the camera is to the surface the greater the bending is.

[WestLangley]

OK, there is no "bending". What you are seeing are depth-buffer artifacts close to the near plane.

The issue is discussed here, and the work-around is to tessellate your geometry -- both boxes in this case.

As stated in the title to this post, the logarithmic depth buffer artifacts occur on devices that do not support the EXT_frag_depth extension, and for which we are handling the logarithmic depth buffer in software.

Fiddle showing the issue:
https://jsfiddle.net/ynom3pgu/ ( or for mobile viewing, https://jsfiddle.net/ynom3pgu/show )

three.js r.90dev

[Avocher]

I see,
Sadly tessellation is not an option for me as I have little to no control over the assets, so I'll just fall back to linear depth buffer when needed.

Thank you so much @WestLangley for helping me out.