[Android] Why is red colour missing from in-game screenshot?

[mnh48]

(As usual) I'm using physical keyboard and mouse with my phone to do anything including playing Minetest. Before, I'll just press Print Screen button where the phone would take screen's screenshot but now I figured out that F12 can be used to trigger in-game screenshot.

What I'm confused is the fact that the red colour is somehow missing from the in-game screenshot (F12):

This is what it should be, this is taken with screen's screenshot (Print Screen):


It is the latest Android Minetest 0.4.15 stable, I did not change much of default setting except:
- GPU Scaling: 0.8
- font_path changed to NotoSansCJKRegular.ttc because default one can't display CJK correctly (I use Japanese and Chinese to chat on some servers, default one just display spaces)
- font_size changed to 12 to adjust comfortable reading

That screenshot is on IhrFussel's Server, but I've also tested in singleplayer and it's the same, so it must be client setting somewhere make it became like that... I've also change the screenshot setting between PNG and JPG, both gives same result, red colour is missing.

Also, how to fix it???

[red-001]

Looks like some sort of weird android related bug, maybe you could make a bug report on github?

[azekill_DIABLO]

your phone is daltonian.

[mnh48]

your phone is daltonian.

no shitposting please, I'm trying to fix this...

you can also try to make some in-game screenshot and post here...

AFAIK, there's no screen overlay to take in-game screenshot, you need F12 button in any way, either via physical keyboard or extended software keyboard app like this.

[azekill_DIABLO]

your phone is daltonian.

no shitposting please, I'm trying to fix this...

you can also try to make some in-game screenshot and post here...

AFAIK, there's no screen overlay to take in-game screenshot, you need F12 button in any way, either via physical keyboard or extended software keyboard app like this.

ok sorry. have you tried to change screenshot output format? quality?

[mnh48]

I have tested all format, they are same

Here's all images link.
JPG (default quality / 0) - https://puu.sh/vkxBA/8927c63639.jpg
JPG (best quality / 100) - https://puu.sh/vkxyF/22d216056b.jpg
PNG - https://puu.sh/vkxA1/0ec78b09ac.png
BMP - https://puu.sh/vkxwz/3493a65383.bmp
PCX - https://puu.sh/vkxqB/cfdcb04b40.pcx
PPM - https://puu.sh/vkxks/c5aae48fcf.ppm
TGA - https://puu.sh/vkx05/48700dca33.tga

[MineYoshi]

Looks like the Red Channel is missing, have you configured OpenGl in your phone, or maybe setted up something about the graphics?

[mnh48]

The original question is using default setting for graphics, but for this post I tried to change the settings.

What appeared as default is ogles1 but it did not exist when click on the dropdown.

The other settings all crashed the app:
opengl
direct3d9
direct3d8
burningsvideo
software

I tried to manually change in minetest.conf to ogles2 and ogles3 in case that could fixed it, but nope... ogles3 crashed the game, ogles2 is buggy and the problem is still not solved:

This is when set to ogles2, even lag than ogles1 and problem still unsolved.

[MineYoshi]

The original question is using default setting for graphics, but for this post I tried to change the settings.

What appeared as default is ogles1 but it did not exist when click on the dropdown.

The other settings all crashed the app:
opengl
direct3d9
direct3d8
burningsvideo
software

I tried to manually change in minetest.conf to ogles2 and ogles3 in case that could fixed it, but nope... ogles3 crashed the game, ogles2 is buggy and the problem is still not solved:

This is when set to ogles2, even lag than ogles1 and problem still unsolved.

May be a problem with the render itself. Being sincerely i do not know the full reason of this, and what might be the solution.

[azekill_DIABLO]

try inverting the graphics of one of your pictures... i found this really weird

[bigfoot]

I have a theory, the red channel is replaced with the blue channel.
The red color is certainly not removed, look at the sky!
Maybe minetest sends #rrggbb to the renderer, and the renderer interpreted it as #bbggrr which would make this become this, and this become this. Hence the orange sky.

[azekill_DIABLO]

engine bug? hard to fix!