PBR Terrain not loading upon quick teleport

[AtlasLinden]

Environment

Both DeltaFPS (7.1.10.10800445603) and ExtraFPS (7.1.11.11565212741)

You are at 121.0, 110.0, 23.2 in Pasta Cake located at simhost-054bc31cb9bd66326.agni
SLURL: http://maps.secondlife.com/secondlife/Pasta%20Cake/121/110/23
(global coordinates 332,153.0, 305,518.0, 23.2)
Second Life Server 2024-10-15.11356152186
Release Notes

CPU: 12th Gen Intel(R) Core(TM) i9-12900HK (2918.4 MHz)
Memory: 32440 MB
OS Version: Microsoft Windows 11 64-bit (Build 26100.2033)
Graphics Card Vendor: NVIDIA Corporation
Graphics Card: NVIDIA GeForce RTX 3050 Ti Laptop GPU/PCIe/SSE2

Windows Graphics Driver Version: 32.0.15.5612
OpenGL Version: 4.6.0 NVIDIA 556.12

Window size: 2560x1369
Font Size Adjustment: 96pt
UI Scaling: 1
Draw distance: 128m
Bandwidth: 3000kbit/s
LOD factor: 1.375
Render quality: 3
Texture memory: 4096MB
Disk cache: Max size 1638.4 MB (100.0% used)

J2C Decoder Version: KDU v7.10.4
Audio Driver Version: OpenAL, version 1.1 ALSOFT 1.23.1 / OpenAL Community / OpenAL Soft: OpenAL Soft
Dullahan: 1.14.0.202408091639
CEF: 118.4.1+g3dd6078+chromium-118.0.5993.54
Chromium: 118.0.5993.54
LibVLC Version: 3.0.21
Voice Server Version: Vivox 4.10.0000.32327.5fc3fe7c.5942f08

Packets Lost: 0/1,137 (0.0%)
October 31 2024 13:26:50

Description

Teleporting from one region using PBR terrain to another and back can cause the terrain to be blank.
https://gyazo.com/31387d846252b01cc48440da443cdac9

Currently this has only reproduced on Atlas Lindens machine.
TPing into a non-PBR Terrain region and back will revert the issue.

Reproduction steps

1. Login to PBR Terrain region
2. TP to another region using PBR terrain
3. TP back to original location

[cosmic-linden]

I got lucky and was able to reproduce this.

[canny]

This issue has been linked to a Canny post: PBR LAND Textures not loading 🎉

[canny]

This issue has been unlinked from a Canny post: PBR LAND Textures not loading 😢

[valeriiaaproductengine]

Failed QA.

This issue is not reproduce on OSX but keeps reproducing on Win10 - see screen recording:

bandicam.2024-11-25.12-13-26-121.mp4

Verified on the Second Life Release 7.1.11.11982653819 (64bit) in the scope of https://github.com/secondlife/iqa/issues/395 on Win10/OSX.

[akleshchev]

Cherry picker cosmic's fx into ExtraFPS.

#3150

[georgebproductengine]

Passed QA.

Verified on the Second Life Release 7.1.11.12041172537 (64bit) on Win10/OSX in the scope of https://github.com/secondlife/iqa/issues/401.