Add support for z-index parameters in Entity which determines the Entity rendering order

engine/src/main/java/com/bartlomiejpluta/base/engine/world/entity/model/DefaultEntity.java

@@ -27,6 +27,10 @@ public class DefaultEntity extends MovableSprite implements Entity {
    private final Vector2f entityScale = new Vector2f(1, 1);
    private Vector2fc entitySetSize;
 
+   @Getter
+   @Setter
+   private int zIndex = 0;
+
    private int animationSpeed = 100;
 
    @Getter

engine/src/main/java/com/bartlomiejpluta/base/engine/world/map/layer/object/DefaultObjectLayer.java

@@ -20,6 +20,9 @@ import java.util.LinkedList;
 import java.util.List;
 import java.util.Queue;
 
+import static java.lang.Float.compare;
+import static java.lang.Integer.compare;
+
 public class DefaultObjectLayer extends BaseLayer implements ObjectLayer {
 
    @Getter
@@ -190,6 +193,7 @@ public class DefaultObjectLayer extends BaseLayer implements ObjectLayer {
    }
 
    private int compareObjects(Entity a, Entity b) {
-      return Float.compare(a.getPosition().y(), b.getPosition().y());
+      var z = compare(a.getZIndex(), b.getZIndex());
+      return z == 0 ? compare(a.getPosition().y(), b.getPosition().y()) : z;
    }
 }