[BUG-225911] Terrain or texture changes sligtly on region crossing, objects blink.

[sl-service-account]

What just happened?

Terrain or texture alters/shifts slightly after avatar crosses border, some objects blink, sometimes avatar blinks, see attachments:

1. Video terrain_changes.webm

   • Color under plant at left top changes from 'sandy' to green and from green to sandy
   • Grass to the right blinks
   • Spot between plant and grass looks like it changes height

   2. Video Avatar Blinks.webm

      • Self explanatory

   3. terrain_weidness.webm

      • Terrain seems to alter slightly, it ispecially noticable by shadows on hills near water
      • Texture seems to be of same quality, prior and after border crossing yet it shifts slightly.

   What were you doing when it happened?

   Crossing back and force between: http://maps.secondlife.com/secondlife/Product%20Engine%203/240/254/22 http://maps.secondlife.com/secondlife/Product%20Engine/238/4/22

   What were you expecting to happen instead?

   At least no blinking, terrain change is not that noticable, but optimally texture should not 'shift', terrain should not change.

   Other information

   Reproes at 519298 and freshly built viewer-neko.

Attachments

• Avatar Blinks.webm 2018-12-05 07:52:25
• terrain_changes.webm 2018-12-05 07:48:05
• terrain_weidness.webm 2018-12-05 07:55:55

Original Jira Fields

| Field | Value | | ------------- | ------------- | | Issue | BUG-225911 | | Summary | Terrain or texture changes sligtly on region crossing, objects blink. | | Type | Bug | | Priority | Unset | | Status | Accepted | | Resolution | Accepted | | Reporter | AndreyK ProductEngine (andreyk.productengine) | | Created at | 2018-12-05T13:01:38Z | | Updated at | 2018-12-06T17:44:56Z | ``` { 'Build Id': 'unset', 'Business Unit': ['Platform'], 'Date of First Response': '2018-12-05T10:39:51.253-0600', "Is there anything you'd like to add?": 'Reproes at 519298 and freshly built viewer-neko.', 'ReOpened Count': 0.0, 'Severity': 'Unset', 'System': 'SL Viewer', 'Target Viewer Version': 'viewer-development', 'What just happened?': "Terrain alters slightly after avatar crosses border, some object blink, sometimes avatar blinks, see attachments:\r\n1. Video terrain_changes.webm\r\n- Color under plant at left top changes from 'sandy' to green and from green to sandy\r\n- Grass to the right blinks\r\n- Spot between plant and grass looks like it changes height\r\n2. Video Avatar Blinks.webm\r\n- Self explanatory\r\n3. terrain_weidness.webm\r\n- Terrain seems to alter slightly, it ispecially noticable by shadows on hills near vater\r\n- Texture seems to be of same quality, yet it shifts.\r\n\r\nNot sure if this is normal or just me being that attentive and noy noticing it before...", 'What were you doing when it happened?': 'Crossing back and force between:\r\nhttp://maps.secondlife.com/secondlife/Product%20Engine%203/240/254/22\r\nhttp://maps.secondlife.com/secondlife/Product%20Engine/238/4/22', 'What were you expecting to happen instead?': "At least no blinking, terrain change is not that noticable, but optimally texture should not 'shift', terrain should not change.", } ```

[sl-service-account]

Kyle Linden commented at 2018-12-05T16:39:51Z

Hi Andrey,

There are two issues here and I have seen both for as long as I can recall.

Terrain -

1. Terrain textures are randomly generated seed that blends all four region textures according to the min and max height. In fact no two avatars will perceive the same texture blend on a region standing right next to each other.
2. Region crossing, and this is purely speculation, may cause the seed from region A to affect texture blending on region B or any region that now perceives you as a child agent.
3. Terrain is effectively another mesh and it has its own Level of Detail (LOD) slider. I noticed you were on graphics setting 1 (Low) so I'm not surprised at all that the distant terrain rendering changed slightly as you moved.

Avatar - That blink is so quick and I've grown so used to seeing it, that I perceive it as a normal part of Second Life.

That all stated. I'm not opposed at all to investigating whether these generally accepted behaviors could be improved. I'll bring it up at our next meeting.

If you have any other information about whether Terrain detail set to high improves the observed land rendering please let me know.

Thanks!

[sl-service-account]

AndreyK ProductEngine commented at 2018-12-05T17:37:17Z, updated at 2018-12-05T17:38:20Z

I also reproed both blink and slight terrain alteration at high, at same machine and 4/7 graphics at nvidia 970. Personally I was not noticing this as well until I started testing region crossings for another bug. Shadows and EEP transitions make terrain differences really stand out.

P.S. Blink might be related to 0,0,0 coordinates move. In such case not sure if it is fixable viewer side, if server says avatar is at 0,0,0 viewer should abide because avatar might be sitting.

[sl-service-account]

AndreyK ProductEngine commented at 2018-12-06T16:20:35Z

There appears to be SL-10118 for avatar blinking part (looks to be similar enoug). Not sure if object blinking and terrain changes need separate jiras.

[sl-service-account]

Graham Linden commented at 2018-12-06T16:36:48Z

We should try to repro the terrain part on release viewer, but I'm not sure how much we can do as the region crossing is a reset of the coordinates.

If there's a way we can base that random seed process on something "universal" with respect to pos (rather than a region-relative pos),

we might be able to achieve consistency.

[sl-service-account]

Kyle Linden commented at 2018-12-06T16:51:56Z

Imported terrain aspect of this report.

[sl-service-account]

AndreyK ProductEngine commented at 2018-12-06T17:44:26Z

We should try to repro the terrain part on release viewer Reproes easily (at least for me) at current release Second Life Release 6.0.0.520636 (64bit). Also can be seen on video from SL-10118.