5 files changed, 30 insertions, 12 deletions
diff --git a/engines/sludge/builtin.cpp b/engines/sludge/builtin.cpp
index 8195fc53f9..909118a2dd 100644
--- a/engines/sludge/builtin.cpp
+++ b/engines/sludge/builtin.cpp
@@ -58,7 +58,7 @@ int speechMode = 0;
 
 Variable *launchResult = NULL;
 
-extern int lastFramesPerSecond, thumbWidth, thumbHeight;
+extern int lastFramesPerSecond;
 extern bool allowAnyFilename;
 extern VariableStack *noStack;
 extern StatusStuff  *nowStatus;
@@ -2460,13 +2460,14 @@ builtIn(showThumbnail) {
 
 builtIn(setThumbnailSize) {
 	UNUSEDALL
+	int thumbHeight, thumbWidth;
 	if (!getValueType(thumbHeight, SVT_INT, fun->stack->thisVar))
 		return BR_ERROR;
 	trimStack(fun->stack);
 	if (!getValueType(thumbWidth, SVT_INT, fun->stack->thisVar))
 		return BR_ERROR;
 	trimStack(fun->stack);
-	if (!g_sludge->_gfxMan->checkSizeValide(thumbWidth, thumbHeight)) {
+	if (!g_sludge->_gfxMan->setThumbnailSize(thumbWidth, thumbHeight)) {
 		Common::String buff = Common::String::format("%i x %i", thumbWidth, thumbWidth);
 		fatal("Invalid thumbnail size", buff);
 		return BR_ERROR;
diff --git a/engines/sludge/graphics.cpp b/engines/sludge/graphics.cpp
index 578e6f65fe..580124f513 100644
--- a/engines/sludge/graphics.cpp
+++ b/engines/sludge/graphics.cpp
@@ -83,6 +83,10 @@ void GraphicsManager::init() {
 	_currentBurnR = 0;
 	_currentBurnG = 0;
 	_currentBurnB = 0;
+
+	// Thumbnail
+	_thumbWidth = 0;
+	_thumbHeight = 0;
 }
 
 void GraphicsManager::kill() {
diff --git a/engines/sludge/graphics.h b/engines/sludge/graphics.h
index 16973a1658..6c5351cb53 100644
--- a/engines/sludge/graphics.h
+++ b/engines/sludge/graphics.h
@@ -167,7 +167,8 @@ public:
 	void saveColors(Common::WriteStream *stream);
 	void loadColors(Common::SeekableReadStream *stream);
 
-	// Thumb nail
+	// Thumbnail
+	bool setThumbnailSize(int thumbWidth, int thumbHeight);
 	bool saveThumbnail(Common::WriteStream *stream);
 	bool skipThumbnail(Common::SeekableReadStream *stream);
 	void showThumbnail(const Common::String &filename, int x, int y);
@@ -222,6 +223,10 @@ private:
 	// Colors
 	uint _currentBlankColour;
 	byte _currentBurnR, _currentBurnG, _currentBurnB;
+
+	// Thumbnail
+	int _thumbWidth;
+	int _thumbHeight;
 };
 
 } // End of namespace Sludge
diff --git a/engines/sludge/sludger.cpp b/engines/sludge/sludger.cpp
index 4f5f204d92..f616fe696b 100644
--- a/engines/sludge/sludger.cpp
+++ b/engines/sludge/sludger.cpp
@@ -79,7 +79,7 @@ Variable *globalVars;
 int numGlobals = 0;
 
 extern Variable *launchResult;
-extern int lastFramesPerSecond, thumbWidth, thumbHeight;
+extern int lastFramesPerSecond;
 
 extern bool allowAnyFilename;
 extern byte fadeMode;
@@ -167,7 +167,6 @@ void initSludge() {
 	launchResult = nullptr;
 
 	lastFramesPerSecond = -1;
-	thumbWidth = thumbHeight = 0;
 	allowAnyFilename = true;
 	noStack = nullptr;
 	numBIFNames = numUserFunc = 0;
diff --git a/engines/sludge/thumbnail.cpp b/engines/sludge/thumbnail.cpp
index 2c7e007f71..dcbcd91db3 100644
--- a/engines/sludge/thumbnail.cpp
+++ b/engines/sludge/thumbnail.cpp
@@ -35,14 +35,23 @@
 
 namespace Sludge {
 
-int thumbWidth = 0, thumbHeight = 0;
+bool GraphicsManager::setThumbnailSize(int thumbWidth, int thumbHeight)
+{
+	if (checkSizeValide(thumbWidth, thumbHeight))
+	{
+		_thumbWidth = thumbWidth;
+		_thumbHeight = thumbHeight;
+		return true;
+	}
+	return false;
+}
 
 bool GraphicsManager::saveThumbnail(Common::WriteStream *stream) {
 
-	stream->writeUint32LE(thumbWidth);
-	stream->writeUint32LE(thumbHeight);
+	stream->writeUint32LE(_thumbWidth);
+	stream->writeUint32LE(_thumbHeight);
 
-	if (thumbWidth && thumbHeight) {
+	if (_thumbWidth && _thumbHeight) {
 		if (!freeze())
 			return false;
 
@@ -117,12 +126,12 @@ void GraphicsManager::showThumbnail(const Common::String &filename, int atX, int
 }
 
 bool GraphicsManager::skipThumbnail(Common::SeekableReadStream *stream) {
-	thumbWidth = stream->readUint32LE();
-	thumbHeight = stream->readUint32LE();
+	_thumbWidth = stream->readUint32LE();
+	_thumbHeight = stream->readUint32LE();
 
 	// Load image
 	Graphics::Surface tmp;
-	if (thumbWidth & thumbHeight) {
+	if (_thumbWidth & _thumbHeight) {
 		if (!ImgLoader::loadPNGImage(stream, &tmp))
 			return false;
 		else