diff --git a/src/plane.cpp b/src/plane.cpp
index 11fd261..d420df9 100644
--- a/src/plane.cpp
+++ b/src/plane.cpp
@@ -105,10 +105,12 @@ void Plane::setBitmap(Bitmap *value)
 {
 	GUARD_DISPOSED;
 
-	if (value)
-		value->ensureNonMega();
-
 	p->bitmap = value;
+
+	if (!value)
+		return;
+
+	value->ensureNonMega();
 }
 
 void Plane::setOX(int value)
diff --git a/src/sprite.cpp b/src/sprite.cpp
index 59ad1db..1581333 100644
--- a/src/sprite.cpp
+++ b/src/sprite.cpp
@@ -152,10 +152,13 @@ void Sprite::setBitmap(Bitmap *bitmap)
 	if (p->bitmap == bitmap)
 		return;
 
-	if (bitmap)
-		bitmap->ensureNonMega();
-
 	p->bitmap = bitmap;
+
+	if (!bitmap)
+		return;
+
+	bitmap->ensureNonMega();
+
 	*p->srcRect = bitmap->rect();
 	p->onSrcRectChange();
 	p->quad.setPosRect(p->srcRect->toFloatRect());
diff --git a/src/window.cpp b/src/window.cpp
index ada0a9c..000aa65 100644
--- a/src/window.cpp
+++ b/src/window.cpp
@@ -717,24 +717,29 @@ void Window::setWindowskin(Bitmap *value)
 {
 	GUARD_DISPOSED;
 
-	if (value)
-		value->ensureNonMega();
-
 	p->windowskin = value;
+
+	if (!value)
+		return;
+
+	value->ensureNonMega();
 }
 
 void Window::setContents(Bitmap *value)
 {
 	GUARD_DISPOSED;
 
-	if (value)
-		value->ensureNonMega();
+	if (p->contents == value)
+		return;
 
 	p->contents = value;
 	p->controlsVertDirty = true;
 
-	if (value)
-		p->contentsQuad.setTexPosRect(value->rect(), value->rect());
+	if (!value)
+		return;
+
+	value->ensureNonMega();
+	p->contentsQuad.setTexPosRect(value->rect(), value->rect());
 }
 
 void Window::setStretch(bool value)