App Environment SkyDome's UV values

I started a visionOS app using Apple's new "App Environment" template, and when I looked at the UV mapping for the half SkyDome, the bottom edge had a UV 'Y' value of 0.318.

Naively, I had assumed the bottom edge of a half dome would have a UV 'Y' value of 0.5 (half way up the texture map).

Is this the standard UV mapping for half a SkyDome?

It has caused some issues when I've applied some HDRIs.

Hello @Todd2

There is no standard UV mapping for a sky dome. A "sky dome" can be any mesh that is sufficiently large enough to block any pixels coming from the player's passthrough environment. The sky dome included in the Xcode app template is an example of such an asset, and you are encouraged to use you own that better matches the experience you are trying to create.

There are some best practices that Apple recommends, and this WWDC video goes into more detail about setting up a sky dome. Typically, a sky dome asset is created in a DCC and imported into Reality Composer Pro/Xcode. This asset will have normals facing inward rather than outward, and will have its own associated UV, texture, and material data. Sky domes typically use unlit materials and have a high resolution texture.

Thank you for your question, please let me know if this didn't clear things up. If you do have more questions, going into more detail about the specific experience you are trying to achieve will help us answer any questions you may have.

App Environment SkyDome's UV values
 
 
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