implement mementos snapshots

1 files changed, 11 insertions, 0 deletions

diff --git a/CanvasData.h b/CanvasData.h
index d2b0666..69e8c8c 100644
--- a/CanvasData.h
+++ b/CanvasData.h
@@ -1,7 +1,18 @@
 #pragma once
 
+#include "Memento.h"
+
 struct CanvasData {
 	unsigned rows = 0;
 	unsigned columns = 0;
 };
 
+class CanvasDataMemento : public Memento {
+	friend class Canvas;
+
+public:
+	CanvasDataMemento(const CanvasData & data) : data(data) {}
+private:
+	CanvasData data;
+};
+