Why i see gaps in terrain rendering at high level of detail?

CesiumJS
1

My problem is gaps (black or see-through lines) in terrain rendering. Difficult to describe, easy to see. Screenshot is here: https://snag.gy/jT5MR0.jpg

I don't understand possible reasons of those gaps in terrain rendering when zooming in close to terrain. Can someone point me in the right direction for investigation?

I've created a terrain tileset from GeoTiff, using command: "ctb-tile in.gif ./terrain_tiles/" from docker image "homme/cesium-terrain-builder". levels of details from 10 to 21.

I load the terrain with simplest example code:
var terrainProvider = new Cesium.CesiumTerrainProvider({
            url : '/my_web_path/terrain_tiles',
        });

Using Cesium 1.18 on Windows 7. It might be something obvious, but i'm stuck and need your help.

2

Hello,

We fixed similar bugs to this in past few releases. Can you update to the most recent version of Cesium to see if that fixes the problem?

Best,

Hannah

3

Unfortunately, there are still gaps on Cesium 1.21 latest.

Orthophoto tiles flipped with flipXY. The rest code is the same. By the way, those gaps are moving along the surface as I move mouse (and change camera angle and titing). Could it be some missed argument to ctb-tiles at generation stage?

4

Hmm, okay. Are the gaps only there temporarily or do they persist? Sometimes there are gaps when tiles are loading in from different levels, but the correct tile should pop in quickly.

-Hannah

5

They do persist. Also tested on latest Firefox and on trunk cesium. Those issues does not change if I turn off/on orthophotoplan image layer.

6

Hmm, I’m not sure what the problem is, sorry. You might want to ask the folks who published cesium terrain builder if they have any tips.

-Hannah