Running FeudalTactics on Mobile Linux

[jonnius]

I tried starting the release desktop jar like java -jar FeudalTactics-desktop.jar on an arm64 Ubuntu Touch Linux device, but keep getting:

[LWJGL] GLFW_API_UNAVAILABLE error
        Description : EGL: Failed to find support for OpenGL
        Stacktrace  :
                org.lwjgl.glfw.GLFW.nglfwCreateWindow(GLFW.java:2058)
                org.lwjgl.glfw.GLFW.glfwCreateWindow(GLFW.java:2229)
                com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application.createGlfwWindow(Lwjgl3Application.java:527)
                com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application.createWindow(Lwjgl3Application.java:463)
                com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application.createWindow(Lwjgl3Application.java:449)
                com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application.<init>(Lwjgl3Application.java:163)
                de.sesu8642.feudaltactics.lwjgl3.Lwjgl3Launcher.createApplication(Lwjgl3Launcher.java:24)
                de.sesu8642.feudaltactics.lwjgl3.Lwjgl3Launcher.main(Lwjgl3Launcher.java:16)
[de.sesu8642.feudaltactics.lwjgl3.Lwjgl3Launcher] the game crashed because of an unexpected exception
com.badlogic.gdx.utils.GdxRuntimeException: Couldn't create window
        at com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application.createGlfwWindow(Lwjgl3Application.java:530)
        at com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application.createWindow(Lwjgl3Application.java:463)
        at com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application.createWindow(Lwjgl3Application.java:449)
        at com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application.<init>(Lwjgl3Application.java:163)
        at de.sesu8642.feudaltactics.lwjgl3.Lwjgl3Launcher.createApplication(Lwjgl3Launcher.java:24)
        at de.sesu8642.feudaltactics.lwjgl3.Lwjgl3Launcher.main(Lwjgl3Launcher.java:16)

I assume, it is requiring OpenGL support, while Ubuntu Touch provides GLES. As you support Android, I assume that GLES should be supported by this game. Is that correct? Can you provide any guidance how to package/start the game so that it utilizes GLES?

[Sesu8642]

I think you might need to edit the config in de.sesu8642.feudaltactics.lwjgl3.Lwjgl3Launcher. See https://libgdx.com/wiki/graphics/opengl-es-support.

[Sesu8642]

Any update on this?

[jonnius]

Thanks for your suggestion and sorry for not getting back on this, yet. I didn't find the time yet to try it out. I will report once there is news.

[jonnius]

I finally got to test again. I found that configuring the OpenGL emulation as suggested doesn't change anything, even though I don't know which version my FP4 with UT actually supports. What I found though is that I only get that error when starting the app from an SSH session, not starting it from the device itself. There it actually starts.

I still have issues, namely that some areas are not clickable (de.sesu8642.feudaltactics.lib.ingame.GameController clicked: null) and that it doesn't seem to support Wayland (only runs through XWayland). Should I close this one and open separate issues for these?

[Sesu8642]

The log line you quote is the expected output if you click water. If you didn't, please open a separate issue.
Wayland support must be implemented in the LibGDX framework which in turn uses LWJGL3. It's out of scope for me but feel free to open an issue there.

[jonnius]

Will open one for the missing clicks after some more testing...

Which version of lwjgl/glfw does this project use? Looking at this issue, it seems that starting with LWJGL 3.3.4 / GLFW 3.4 it would run natively on Wayland.

[Sesu8642]

Its using 3.3.3. libGDX downgraded it after there were some antivirus detection problems. See LWJGL/lwjgl3#1005
It seems to be fixed in 3.3.6 but the latest libGDX still uses 3.3.3. I will upgrade after libGDX does so.

[jonnius]

Where can I see/configure the versions for testing?

[jonnius]

Just for reference, I pushed my packaging test configuration here: https://github.com/jonnius/FeudalTactics/tree/ut

[Sesu8642]

The dependency on gdx-backend-lwjgl3 is defined in lwjgl3/build.gradle. Here you should be able to override the version of the transitive lwjgl3 dependency.
https://stackoverflow.com/questions/28444016/how-can-i-force-gradle-to-set-the-same-version-for-two-dependencies

[jonnius]

I added the following in lwjgl3/build.gradle:

configurations.all {
    resolutionStrategy {
        force("org.lwjgl:lwjgl-glfw:3.3.6")
    }
}

This leads to

Apr 27 17:19:31 ubuntu-phablet aa-exec[50165]: [LWJGL] Failed to load a library. Possible solutions:
Apr 27 17:19:31 ubuntu-phablet aa-exec[50165]:         a) Add the directory that contains the shared library to -Djava.library.path or -Dorg.lwjgl.librarypath.
Apr 27 17:19:31 ubuntu-phablet aa-exec[50165]:         b) Add the JAR that contains the shared library to the classpath.
Apr 27 17:19:31 ubuntu-phablet aa-exec[50165]: [LWJGL] Enable debug mode with -Dorg.lwjgl.util.Debug=true for better diagnostics.
Apr 27 17:19:31 ubuntu-phablet aa-exec[50165]: [LWJGL] Enable the SharedLibraryLoader debug mode with -Dorg.lwjgl.util.DebugLoader=true for better diagnostics.
Apr 27 17:19:31 ubuntu-phablet aa-exec[50165]: Exception in thread "main" java.lang.UnsatisfiedLinkError: Failed to locate library: liblwjgl.so

[Sesu8642]

Probably upgrading takes more than just pulling the new version.
Another option is to set gdxVersion=1.13.0 in gradle.properties. It does start and actually gives me some Wayland error messages in the background.

[jonnius]

Unfortunately, that leads to the same result of the missing liblwjgl.so. :(

[Sesu8642]

Does your jar run on x86 Linux? I checked the contents and the .so file for arm64 seems to be present. It might be a bug in libGDX.