fix: add 'isWaylandSession'

Author: JNightRider

jme3-core/src/main/java/com/jme3/system/JmeSystemDelegate.java

@@ -159,13 +159,13 @@ public boolean isDeviceRumbleSupported() {
         return false;
     }
 
-    @Override
-    public void rumble(float amountHigh, float amountLow, float duration) {
-    }
-
-    public final AssetManager newAssetManager(URL configFile) {
-        return new DesktopAssetManager(configFile);
-    }
+    @Override
+    public void rumble(float amountHigh, float amountLow, float duration) {
+    }
+
+    public final AssetManager newAssetManager(URL configFile) {
+        return new DesktopAssetManager(configFile);
+    }
 
     public final AssetManager newAssetManager() {
         return new DesktopAssetManager(null);
@@ -317,7 +317,15 @@ public String getBuildInfo() {
         sb.append(" * Build Date: ").append(JmeVersion.BUILD_DATE);
         return sb.toString();
     }
-    
+
+    public boolean isWaylandSession() {
+        // The following matches the test GLFW does to enable the Wayland backend.
+        if ("wayland".equalsIgnoreCase(System.getenv("XDG_SESSION_TYPE")) && System.getenv("WAYLAND_DISPLAY") != null) {
+            return true;
+        }
+        return false;
+    }
+
     public abstract URL getPlatformAssetConfigURL();
 
     public abstract JmeContext newContext(AppSettings settings, JmeContext.Type contextType);