Android: Black screen with post-processing

[Yonle]

Minetest version

5.7.0

OS / Hardware

Operating system: ARM64 Android
CPU: Cortex-A53

GPU model: PowerVR GE8320, 650 MHz
OpenGL version: -

Summary

First time playing resulting in black screen. No Mods or any plugins installed yet. World created with default configuration.

Changing camera also does not helps.

Steps to reproduce

1. Start Minetest for the first time
2. Create world without changing anything
3. Get in

[Yonle]

Downgrading to 5.6.1 works.

[Yonle]

But upgrading from 5.6.1 to 5.7.0 also leads to black screen.

[srifqi]

I can not reproduce it (on Samsung Galaxy A72, GPU: Adreno 618). Both versions mentioned in this thread can run normally.

Have you tried to set the video driver (video_driver) to ogles1 in the 5.7.0 version? It is in the All Settings -> Advanced -> Advanced -> Graphics -> Video driver.

[Yonle]

Have you tried to set the video driver (video_driver) to ogles1 in the 5.7.0 version? It is in the All Settings -> Advanced -> Advanced -> Graphics -> Video driver.

I did not modify anything on the settings yet, So i am doing it now.

It works, But some UI is buggy.

[sfan5]

ogles1 will not be supported in the future, so if it doesn't work we have to fix that anyway.
Do you have the debug.txt / log file?

[Yonle]

debug.txt

[nininik0]

Maybe you should delete the app and then install it again or switch to OGLES2 #13580

[joshuaruxpin]

had same issue trying to run on chromebook

[Yonle]

Disabling shader makes the black screen gone.

[nininik0]

Yes but disabling shader causes stuff to render in fulbright #13511 #13580

[Yonle]

Yes but disabling shader causes stuff to render in fulbright #13511 #13580

Could confirm.

[Unacceptium]

i got the same issue on my gigaset, android 9! i changed the video driver and shaders and that solved

[grorp]

Unfortunately, I can't reproduce this either (OnePlus Nord CE 2 Lite / CPH2409), and the log posted by Yonle doesn't seem to contain anything useful...

[erlehmann]

Here is a list of mobile devices that have the PowerVR GE8320 GPU (same as the submitter):
https://mobile.phonebunch.com/phone-filter/gpu/powervr-ge8320/page/1/

I also found this PR for GLideN64 that may be related: gonetz/GLideN64#2633

Newer PowerVR devices need depth to be cleared every frame, otherwise most geometry is rendered behind the background.

It also needs fragment based depth to be disabled, otherwise geometry has various depth glitches.

Edit: See gonetz/GLideN64#2108 (comment) for screenshots of the GLideN64 bug that may or may not be related.

[Unacceptium]

@erlehmann i'm not a programmer, but i can't logic out how that polygon issue related.

edit: as i said, changing video driver, fog and shaders helped me. i get that white background hud wich @Yonle screenshoted above.

[SmallJoker]

For those affected by this bug: Please post your GPU model (see CPU-Z app for example) and the relevant excerpt from debug.txt (and/or logcat) to narrow down whether it's a shader compiling error or related to a specific GPU.

Unfortunately there does not seem to be a Minetest developer who could reproduce this issue to work on a fix, hence community inputs are highly welcomed. Removing from the 5.8.0 milestone to not hold back its release due to a specific hardware problem of certain models.

[Unacceptium]

the phone i reproduced the issue is a higaset gs190 wich is
SoC/CPU: MediaTek Helio A22 MT6761
GPU: Mali-G72 MP3
4 core
is this helpful?

[sfan5]

the good news: I can reproduce this issue on Linux with a Mali-450 GPU and the Mesa driver (so not some proprietary stuff that's impossible to debug). That also means there's a good chance there's an actual bug.

the bad news: this board is very slow at compiling and I don't have the expertise or time to continue debugging this.

[sfan5]

should be re-tested after #14338 and #14405

[Yonle]

Unfortunately i no longer have the same phone to retest the new build.

[sfan5]

Good news: time and motivation to re-test this came back.
More good news: disabling post-processing fixes this issue. Since it's disabled by default on Android we don't have to worry about this for now.

[grorp]

The post-processing pipeline creates a depth texture (not renderbuffer) for off-screen rendering (see src/client/render/secondstage.cpp)

Looking at this code:

https://github.com/minetest/minetest/blob/60cd1e452957e2e924eedf9de6b46f6eb7833ccc/irr/src/OpenGLES2/Driver.cpp#L99-L105

There can be cases with OpenGL ES 2 where no depth texture format is supported at all. This would obviously result in texture creation failing, the framebuffer would be invalid/incomplete and we'd have the issue described here.

[sfan5]

A second problem is the usage of GL_BGRA, which is an unsized format, for creating a render target. This doesn't work and never will.
The required combination for this problem to appear is:

• GLES 2.x
• EXT_texture_format_BGRA8888 supported
• OES_texture_half_float not supported

edit: this might have been wrong actually, but doesn't matter now.