[Bug?] MergeMeshes() results in mesh artifacts on Kindle Fire 7

[Nodragem]

When running on Silk Browser on Amazon Kindle Fire 7 the Mesh Merge function results in garbled mesh artifacts.

 

Note that the merging works very well on Android and Apple device (using Chrome, or Safari).

I am going to report it on Github, but if you have reasons to think that this is not a bug, please let me know.

[Nodragem]

So I try to reproduce the bug on the Playground, and I could not do it simply.

For now I succeeded to reproduce the texture black artefacts but not the texture green artefact. I could not reproduce the geometry artefacts either (I mean the artefact that change the geometry of the maze).

The texture black artefact seems to come from the use of BABYLON.PBRMetallicRoughnessMaterial; see the playground here: https://playground.babylonjs.com/#INZ0Z0#30

This is how the PG is rendered on the Amazon Fire 7:

The problem occurs even without the mergeMeshes() call.

[bghgary]

@Nodragem Can you go to http://webglreport.com/ on your device and post the results?

[Nodragem]

Yep I will do but I am more concerned about the geometry artefacts which seems to result from mergeMeshes();

Concerning the black artefact I can use StandardMaterial for now

[bghgary]

Sure. Ping if you find a way to repro the geometry issue with a playground.

[Nodragem]

I just saw that there is a dedicated section for bugs. How can I move my thread to that section?

[bghgary]

Either way. This is kind of a gray area since we don't know if it actually is a bug in Babylon or something with the Silk Browser or the drivers on the Fire.

[brianzinn]

Have you tried dialing back some settings, like disabling webgl2 in engine options or engine.getCaps().highPrecisionShaderSupported = false;  It may be possible that the BabylonJS engine needs to account for a bug in the the browser/driver as @bghgary has suggested.

When I look at your first screenshot it looks like z-fighting with 2 planes - those misplaced triangles look like a face that does not belong.  I've tried mesh merging and was happier with more fine grained control using meshes generated manually (from data files). I was originally inspired by some code from this project (/scripts/PlanetChunckMeshBuilder), which is efficient and produces minimum vertices (ie: skipping occluded faces) :
http://svenfrankson.github.io/PlanetBuilderWeb/index.html