Starting at about engine version 4.16.2, my project started to show some bizarre rendering issues. I managed to track the issues to my textures that were marked with Mip Gen Settings “NoMipmaps”, however it is unclear if mipmaps are the sole perpetrator, as the SkySphere night effects seem to always have the artifact present. (or my changes to the texture are not perpetrating through the package chain all the way to the build)
Specifically, the materials using the no-mipmap textures began to render only a thin strip (U: 0 to 1, V: 0 to 0.1ish) of the specified texture, like as if it were trying to use mip map coordinates on a non-mipmap texture. This only occurred on the android packaged builds with etc1 configuration, and not within the editor, regardless of the preview feature level.
Steps to Reproduce:
1. Create a new 3rd Person project with mobile target, scalable 2D/3D, no starter content.
2. Change the skysphere to night time, either by rotating the light source, or disconnecting the light source and setting sun height to -1.
3. Configure the project for android in the project settings
4. Package the project for Android ETC1.
5. Install, run, and observe the thin streaks through the sky, instead of regular stars.
I did some experimentation to see if I could determine the exact cause, but all I could determine was that the bug did not affect all materials, the ones that I had made that were affected were fixed by changing mipmaps from none to “from texture group” (world group), and that the skysphere night sky stars always seemed to have the problem, regardless of texture settings (However, I have also noticed that changes to materials and textures don’t always get packaged unless other significant changes are made to the project. Perhaps a separate bug? So it may be that changing those properties fixes the skysphere, and I simply didn’t get to see the changes in the build).
I am running the packaged build on a Nexus 6p running Android 7.1.2
