[Bug] Texture2D does not work on Android

[lattice0]

I believe this is a bug because the exact same code won't work on Android but works in PC, with exception to the context/window creation. For that I'm using @MarijnS95 updates to both glutin/glium because they don't compile for Android

Here's a minimum verifiable example: https://github.com/lattice0/AndroidNativeSurface/tree/texture (branch is texture) and the same cargo project of the Android project (https://github.com/lattice0/AndroidNativeSurface/tree/texture/android_native_surface) can also be run with cargo run on desktop, where it will produce a pattern in the texture:

(error is because I did not start the event loop correctly but whatever)

In summary, the following won't work:

            let texture =
                Texture2d::empty_with_format(&display, format, mipmap, width, height).unwrap();
            let mut data: Vec<Vec<u8>> = Vec::new();
            for i in 0..width {
                let mut v: Vec<u8> = Vec::new();
                for j in 0..height {
                    v.push((i * j % 255) as u8);
                }
                data.push(v);
            }

            texture.write(
                glium::Rect {
                    left: 0,
                    bottom: 0,
                    width,
                    height,
                },
                data,
            );

On Android you can uncomment FragColor to be red so you can see that at least the square is being renderer:

                void main() {
                    vec4 a = texture(tex, v_tex_coords);
                    FragColor = vec4(a.r,0.0,0.0,1.0);
                    //Uncomment to see that at least rendering the red square works
                    //FragColor = vec4(1.0,0.0,0.0,1.0);
                },

[faern]

I wonder if this is the same issue I'm seeing when using glium with a GTK4 application? I have the same behavior: When I draw a glium texture in a winit window (like the glium examples) it works, but when I try to draw with the exact same code on a GTK GLArea then nothing at all shows up. No errors are printed, so it's as if the texture(...) function in the fragment shader just always returns black). I reported it to gtk4-rs but did not get a response yet: gtk-rs/gtk4-rs#1647