[Features] End Source has fallbacks if barrens/voids or center Biomes are missing

src/main/java/org/betterx/bclib/api/v2/generator/BCLibEndBiomeSource.java

@@ -62,9 +62,9 @@ public class BCLibEndBiomeSource extends BCLBiomeSource implements BiomeSourceWi
     private BiomeMap mapBarrens;
 
     private final BiomePicker endLandBiomePicker;
-    private final BiomePicker endVoidBiomePicker;
+    private BiomePicker endVoidBiomePicker;
-    private final BiomePicker endCenterBiomePicker;
+    private BiomePicker endCenterBiomePicker;
-    private final BiomePicker endBarrensBiomePicker;
+    private BiomePicker endBarrensBiomePicker;
 
     private BCLEndBiomeSourceConfig config;
 
@@ -171,6 +171,20 @@ public class BCLibEndBiomeSource extends BCLBiomeSource implements BiomeSourceWi
         endBarrensBiomePicker.rebuild();
         endCenterBiomePicker.rebuild();
 
+        if (endVoidBiomePicker.isEmpty()) {
+            BCLib.LOGGER.info("No Void Biomes found. Disabling by using barrens");
+            endVoidBiomePicker = endBarrensBiomePicker;
+        }
+        if (endBarrensBiomePicker.isEmpty()) {
+            BCLib.LOGGER.info("No Barrens Biomes found. Disabling by using land Biomes");
+            endBarrensBiomePicker = endLandBiomePicker;
+            endVoidBiomePicker = endLandBiomePicker;
+        }
+        if (endCenterBiomePicker.isEmpty()) {
+            BCLib.LOGGER.warning("No Center Island Biomes found. Forcing use of vanilla center.");
+            endCenterBiomePicker.addBiome(BiomeAPI.THE_END);
+        }
+
         this.endLandFunction = GeneratorOptions.getEndLandFunction();
         this.pos = new Point();
 

src/main/java/org/betterx/bclib/api/v2/generator/BiomePicker.java

@@ -62,6 +62,10 @@ public class BiomePicker {
         return biomes.isEmpty() ? fallbackBiome : tree.get(random);
     }
 
+    public boolean isEmpty() {
+        return biomes.isEmpty();
+    }
+
     public void rebuild() {
         WeightedList<ActualBiome> list = new WeightedList<>();