"getNativeWindowHandle+0x54" on Gluon JavaFX 16 EA 4 via DRM - javafx

Question

I was following the steps given at Gluon Documentation to run JavaFX on Raspberry Pi 4 via DRM. I downloaded the JavaFX EA 16 builds from here.
javafx.properties file :
javafx.version=16-internal
javafx.runtime.version=16-internal+28-2020-11-10-180413
javafx.runtime.build=28
After cloning the samples repository containing hellofx, I compiled it via javac (according to the steps) and then ran this command to run it using DRM:
sudo -E java -Dmonocle.platform=EGL -Djava.library.path=/opt/arm32hfb-sdk/lib -Dmonocle.egl.lib=/opt/arm32fb-sdk/lib/libgluon_drm.so --module-path /opt/arm32fb-sdk/lib --add-modules javafx.controls -cp dist/. hellofx.HelloFX
However, this caused the following error :
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x9c3314dc, pid=734, tid=746
#
# JRE version: OpenJDK Runtime Environment (11.0.9+11) (build 11.0.9+11-post-Raspbian-1deb10u1)
# Java VM: OpenJDK Server VM (11.0.9+11-post-Raspbian-1deb10u1, mixed mode, serial gc, linux-)
# Problematic frame:
# C [libgluon_drm.so+0x14dc] getNativeWindowHandle+0x54
#
# No core dump will be written. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#
# An error report file with more information is saved as:
# /home/pi/samples/CommandLine/Modular/CLI/hellofx/hs_err_pid734.log
#
# If you would like to submit a bug report, please visit:
# Unknown
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#
Aborted
It seems that while loading libgluon_drm.so in JavaFXSDK/lib/ fails at getNativeWindowHandle
What's weird is that after I ran sudo apt install libegl* mesa* libgl*, it actually succeeded but was asking me to set variable ENABLE_GLUON_COMMERCIAL_EXTENSIONS as true, which I had already done.
However, after rebooting, it started showing the same error.
I am using a Raspberry Pi 4 Model B with 2GB RAM. It is running on Raspberry Pi OS 32-Bit with desktop.
I had performed all of this on a clean installation.

Answer 1

Pi4 has both vc4 for render, and v3d for 3D. You can probe the devices for their capabilities - only one should acknowledge that it has DRIVER_RENDER or DRIVER_MODESET capabilities.
Pi4 DRM questions
The card which JavaFX selects by default is /dev/dri/card1. In my case, /dev/dri/card0 was the one to be used for render, and not card1. I solved the issue by using the following runtime argument :
-Degl.displayid=/dev/dri/card0
The JavaFX Version I used was 16-ea+5.