box重载overlaps

source/src/Physics/Shapes/Box.ts

@@ -21,6 +21,22 @@ class Box extends Polygon {
         return verts;
     }
 
+    /**
+     * 
+     * @param other 
+     */
+    public overlaps(other: Shape){
+        if (this.isUnrotated){
+            if (other instanceof Box && other.isUnrotated)
+                return this.bounds.intersects(other.bounds);
+
+            if (other instanceof Circle)
+                return Collisions.isRectToCircle(this.bounds, other.position, other.radius);
+        }
+
+        return super.overlaps(other);
+    }
+
     /**
      * 
      * @param other 

source/src/Physics/Shapes/ShapeCollisions/ShapeCollisions.ts

@@ -270,9 +270,11 @@ class ShapeCollisions {
             
             result.normal = new Vector2(-result.minimumTranslationVector.x, -result.minimumTranslationVector.y);
             result.normal.normalize();
+
+            return result;
         }
 
-        return result;
+        return null;
     }
 
     private static minkowskiDifference(first: Box, second: Box){