Add a warning when trying to add multiple textures with the same name…

… so this doesn't happen again.

chunky/src/java/se/llbit/chunky/resources/TexturePackLoader.java

@@ -19,6 +19,7 @@
 import se.llbit.chunky.renderer.scene.PlayerModel;
 import se.llbit.chunky.renderer.scene.sky.Sun;
 import se.llbit.chunky.resources.texturepack.*;
+import se.llbit.log.Log;
 
 import java.lang.reflect.Field;
 import java.util.*;
@@ -3663,6 +3664,10 @@ private static void addSimpleTexture(String file, Texture texture) {
   }
 
   private static void addSimpleTexture(String name, String file, Texture texture) {
+    if (ALL_TEXTURES.containsKey(name)) {
+      Log.warnf("Duplicate texture %s (path %s). This is probably a bug, please report it at https://github.com/chunky-dev/chunky/issues", name, file);
+      addSimpleTexture(name + "_duplicate", file, texture);
+    }
     ALL_TEXTURES.put(name, new SimpleTexture(file, texture));
   }
 }