Animated pbr textures don't animate

[canny]

Objects with an animated pbr textures stop animating the texture when we look elsewhere and back to the object.

A right click on the object triggers the animation again.

(a bit like the object not spinning as they should, a right click does the trick)

Happens on mac and pc

This doesn't happen if the material is not pbr.

https://secondlife.canny.io/admin/board/bug-reports/p/deltafps-extrafps-animated-pbr-textures-dont-animate

Test plan

• PBR materials with texture animations should start animating when visible, within a reasonable timeframe
• PBR materials with texture animations should not semi-permanently stop animating when looking away and then looking back
• Texture animations should have the expected texture transforms and animations

[canny]

This issue has been linked to a Canny post: [deltaFPS] [extraFPS] Animated pbr textures don't animate 🎉

[AtlasLinden]

Reproduced on both DeltaFPS (7.1.10.10800445603) and ExtraFPS (7.1.11.11074622243)
Clip of repro: https://gyazo.com/837144fbea9b84d5456bd3108a44f851

[canny]

This issue has been linked to a Canny post: Animated PBR textures using llSetTextureAnim appear randomly broken in the recent SL viewers 🎉

[cosmic-linden]

In my local dev build, I think I've fixed the part of this issue where the texture animations stops when looking away. However, the texture animation still sometimes fails to play on login. I will open a PR with the fix so far, and continue looking in to this ticket.