selection fix again

src/ui/view/MyCanvas.java

@@ -412,7 +412,14 @@ public class MyCanvas extends JPanel implements MouseListener, MouseMotionListen
 			controller.addSelectedObject(tempCps);
 		}
 		if (e.isControlDown()) {
-			controller.addSelectedObject(tempCps);
+			if (model.getSelectedCpsObjects().contains(tempCps)) {
+				model.getSelectedCpsObjects().remove(tempCps);
+				if (model.getSelectedCpsObjects().isEmpty()) {
+					tempCps = null;
+				}
+			} else {
+				controller.addSelectedObject(tempCps);
+			}
 		}
 		if (dragged == true) {
 			try {