README improvements?

[rubyFeedback]

Hi,

I know there will be a larger introduction at 2022-02-05, but would it be possible to
expand the main README afterwards as well? Many people still remember the
original directfb, so it is of course interesting to them what directfb2 may bring
to the table and such.

[directfb2]

Hi,

There is some information in the NEWS file. Hope this gives an idea on DirectFB2 versus DirectFB.
But yes, more explanation should be added.

Nicolas Caramelli

[oceanmar]

What flavor/distro you’re using with directfb2?

[caramelli]

Whenever I start on a new embedded platform, I usually build my system from scratch, just using the cross compiler (with its C library), the Linux kernel, the busybox, and then immediately test the display with DirectFB2. In particular, I hope to run DirectFB2 on MCUs with an embedded OS like FreeRTOS.

I guess DirectFB2 can easily be integrated into Buildroot or Yocto.
DirectFB2 can also be built on your native distro: switch to a virtual console to test it.

[oceanmar]

@caramelli i asked because i compiled directfb2 to a freshly installed debian without x only the basic. when i try the examples gave me some problems

[caramelli]

I never had a DRM_IOCTL_GEM_FLINK failure, I have no explanation, this is to be investigated...
You can try the following test: echo system=fbdev > ~/.directfbrc
And then run a DirectFB example.

[oceanmar]

i've done as you suggested but nothing. another thing i noticed that when i run directfb examples it opens another tty and when i return to tty1 the error in the image above is shown.

[caramelli]

But this time with the fbdev system, I guess you don't get a DRM_IOCTL_GEM_FLINK failure?

[oceanmar]

i still have

[caramelli]

OK, you can check that the fbdev system module libdirectfb_fbdev.so is built and installed.

I also recommend checking that at least one of the FBDev or DRM/KMS graphics backends is working properly on your distro before running DirectFB:

• for fbdev : cat /dev/urandom > /dev/fb0
• for DRM/KMS : modetest -s connector_id:mode

[oceanmar]

• libdirectfb_fbdev.so is not installed because i didn't installed x.

-for fbdev : cat /dev/urandom > /dev/fb0

maybe because i'm using virtualbox

-for DRM/KMS : modetest -s connector_id:mode

gave a screen with different color just like an old tv

[caramelli]

It looks good. The X Window System is not required.
You can check if libdirectfb_fbdev.so is installed with : ls directfb-2.0-0/systems
Just for testing, to be sure that the drmkms system module will not be used, just remove it:
rm directfb-2.0-0/systems/libdirectfb_drmkms.so

[oceanmar]

@caramelli . thank you so much it works. tomorrow ill try how to run multiple windows at once, because everytime i try to run multiple examples at once just like in the wiki i only get one window running in the middle.

[oceanmar]

i can't compile and install linux-fusion :(. im editing the Makefile for kernel 5.10.0.11 but nothing.

[caramelli]

As you can see, the latest code available at https://github.com/deniskropp/linux-fusion has not been updated for many years.
In particular, in the Makefile:

ifeq ($(K_VERSION),3)
KMAKEFILE = Makefile-2.6
else
KMAKEFILE = Makefile-2.$(K_PATCHLEVEL)
endif

With K_VERSION equal to 5, yes, there are probably changes to add on linux-fusion for the build.
It would be nice and any help to do this is welcome!

[oceanmar]

In fact that is the source i’m tinkering now eithout breaking the system, i’m not that proficient with kernels