sm sec fixes

DrawFigureLibrary/Figure.cs

@@ -28,8 +28,19 @@ namespace DrawFigureLibrary
 
         public override string ToString() => Name ?? "";
 
-        public static bool Check(Figure fig, int dX, int dY, Image img) => fig.x + dX >= 0 && fig.y + dY >= 0 && fig.x + dX + fig.w <= img.ActualWidth && fig.y + dY + fig.h <= img.ActualHeight;
-        
+        public static bool Check(Figure fig, int dX, int dY, Image img)
+        {
+            long nx = (long)fig.x + dX;
+            long ny = (long)fig.y + dY;
+            long nr = nx + fig.w;
+            long nb = ny + fig.h;
+
+            return nx >= 0 &&
+                   ny >= 0 &&
+                   nr <= (long)img.ActualWidth &&
+                   nb <= (long)img.ActualHeight;
+        }
+
         public virtual bool HitTest(Point p) => p.X >= x && p.X <= x + w && p.Y >= y && p.Y <= y + h;
         
         public virtual bool MoveByChecked(int dX, int dY)