Avatar rotates 360 degrees when viewed from the top and below using "Front View" mode in the "Camera Controls" floater

[dmytrohproductengine]

Environment

Second Life Release 7.1.6.8632452945 (64bit)
Release Notes

You are at 211.9, 108.9, 21.5 in Product Engine located at simhost-04b8dd6c12cd9dd86.agni
SLURL: http://maps.secondlife.com/secondlife/Product%20Engine/212/109/22
(global coordinates 336,852.0, 307,309.0, 21.5)
Second Life Server 2024-03-18.8333615376
Release Notes

CPU: Intel(R) Core(TM) i7-8700K CPU @ 3.70GHz (3696.01 MHz)
Memory: 32688 MB
OS Version: Microsoft Windows 10/11 64-bit (Build 22631.3155)
Graphics Card Vendor: ATI Technologies Inc.
Graphics Card: Radeon RX 5500 XT

Windows Graphics Driver Version: 31.0.12027.9001
OpenGL Version: 4.6.0 Core Profile Context 22.20.27.09.230330

Window size: 1920x1009
Font Size Adjustment: 96pt
UI Scaling: 1
Draw distance: 128m
Bandwidth: 3000kbit/s
LOD factor: 1.5
Render quality: 4
Texture memory: 20167MB
Disk cache: Max size 1638.4 MB (19.2% used)

J2C Decoder Version: KDU v7.10.4
Audio Driver Version: FMOD Studio 2.02.20
Dullahan: 1.14.0.202310131404
CEF: 118.4.1+g3dd6078+chromium-118.0.5993.54
Chromium: 118.0.5993.54
LibVLC Version: 3.0.16
Voice Server Version: Vivox 4.10.0000.32327.5fc3fe7c.399bd0e

Packets Lost: 0/6,420 (0.0%)
April 11 2024 04:37:07

Description

See Reproduction steps.

Reproduction steps

1. Open the Viewer and log in.
2. Click the "Camera controls" toolbar button and choose the "Front View" option.
3. Left-click and hold the mouse button on the avatar.
4. Drag down/up the mouse until it stops (an avatar is viewed from the top/below).
5. Observe the avatar's screen position.

Actual result:
Avatar rotates 360 degrees when viewed from the top and below using "Front View" mode in the "Camera Controls" floater.

Expected result:
Avatar shouldn't rotate when viewed from the top and below using "Front View" mode in the "Camera Controls" floater.

Note:
This issue is reproduced on Win11/Win10/OSX.

This issue was found during ad-hoc testing of secondlife/jira-archive-internal/issues/69593.

This issue is not reproduced on the current production build Second Life Release 7.1.5.8443591509.

actual.mp4
https://github.com/secondlife/viewer/assets/150431068/ccb16fd7-a0ee-49f2-ad7b-920543a195f2

Test Plan (for different camera modes)

1. Follow the Reproduction steps listed above

2. Repeat these steps with different view modes

3. Repeat these steps in Mouse Look mode (press "M")

4. Fly using any transport like kart or helicopter
   and try to reproduce the bug using the same steps

5. Repeat the same steps with a custom preset copied from Rear view

6. Open 'Camer controls'
   Select 'Front view'
   Click 'Save as preset' button
   Choose 'Replace a preset' and select 'Rear'
   (then repeat and select 'Side')
   Click 'Save as preset' button once again
   And save as new preset.
   Try reproduction steps again

7. Check vehicles on vertical surfaces, like here: [Featurettes] Regression in anti-flipping mechanism for mouselook camera #1611

[LLGuru]

Fixed in #1240

[LLGuru]

Fixed by #1240