MADS: Refactor MSurface and Screen to not use virtual inheritance

19 files changed, 69 insertions, 59 deletions

diff --git a/engines/mads/dragonsphere/dragonsphere_scenes.cpp b/engines/mads/dragonsphere/dragonsphere_scenes.cpp
index a18d03d143..c20eeb72fa 100644
--- a/engines/mads/dragonsphere/dragonsphere_scenes.cpp
+++ b/engines/mads/dragonsphere/dragonsphere_scenes.cpp
@@ -201,7 +201,7 @@ Common::String DragonsphereScene::formAnimName(char sepChar, int suffixNum) {
 
 /*------------------------------------------------------------------------*/
 
-void SceneInfoDragonsphere::loadCodes(MSurface &depthSurface, int variant) {
+void SceneInfoDragonsphere::loadCodes(BaseSurface &depthSurface, int variant) {
 	Common::String ext = Common::String::format(".WW%d", variant);
 	Common::String fileName = Resources::formatName(RESPREFIX_RM, _sceneId, ext);
 	if (!Common::File::exists(fileName))
@@ -217,7 +217,7 @@ void SceneInfoDragonsphere::loadCodes(MSurface &depthSurface, int variant) {
 	f.close();
 }
 
-void SceneInfoDragonsphere::loadCodes(MSurface &depthSurface, Common::SeekableReadStream *stream) {
+void SceneInfoDragonsphere::loadCodes(BaseSurface &depthSurface, Common::SeekableReadStream *stream) {
 	byte *destP = (byte *)depthSurface.getPixels();
 	byte *walkMap = new byte[stream->size()];
 	stream->read(walkMap, stream->size());
diff --git a/engines/mads/dragonsphere/dragonsphere_scenes.h b/engines/mads/dragonsphere/dragonsphere_scenes.h
index e9b48715db..22d894b9d9 100644
--- a/engines/mads/dragonsphere/dragonsphere_scenes.h
+++ b/engines/mads/dragonsphere/dragonsphere_scenes.h
@@ -647,9 +647,9 @@ public:
 class SceneInfoDragonsphere : public SceneInfo {
 	friend class SceneInfo;
 protected:
-	virtual void loadCodes(MSurface &depthSurface, int variant);
+	virtual void loadCodes(BaseSurface &depthSurface, int variant);
 
-	virtual void loadCodes(MSurface &depthSurface, Common::SeekableReadStream *stream);
+	virtual void loadCodes(BaseSurface &depthSurface, Common::SeekableReadStream *stream);
 
 	/**
 	* Constructor
diff --git a/engines/mads/font.cpp b/engines/mads/font.cpp
index 3828c3df8e..684418da91 100644
--- a/engines/mads/font.cpp
+++ b/engines/mads/font.cpp
@@ -145,7 +145,7 @@ void Font::setColorMode(SelectionMode mode) {
 	}
 }
 
-int Font::writeString(MSurface *surface, const Common::String &msg, const Common::Point &pt,
+int Font::writeString(BaseSurface *surface, const Common::String &msg, const Common::Point &pt,
 		int spaceWidth, int width) {
 	int xEnd;
 	if (width > 0)
diff --git a/engines/mads/font.h b/engines/mads/font.h
index 486cadcfff..a27de6e283 100644
--- a/engines/mads/font.h
+++ b/engines/mads/font.h
@@ -86,7 +86,7 @@ public:
 	int maxWidth() const { return _maxWidth; }
 	int getWidth(const Common::String &msg, int spaceWidth = -1);
 	int getHeight() const { return _maxHeight; }
-	int writeString(MSurface *surface, const Common::String &msg, const Common::Point &pt,
+	int writeString(BaseSurface *surface, const Common::String &msg, const Common::Point &pt,
 		int spaceWidth = 0, int width = 0);
 };
 
diff --git a/engines/mads/messages.cpp b/engines/mads/messages.cpp
index 2bee77dae7..773ebd309c 100644
--- a/engines/mads/messages.cpp
+++ b/engines/mads/messages.cpp
@@ -558,7 +558,7 @@ void TextDisplayList::setDirtyAreas2() {
 	}
 }
 
-void TextDisplayList::draw(MSurface *s) {
+void TextDisplayList::draw(BaseSurface *s) {
 	for (uint idx = 0; idx < size(); ++idx) {
 		TextDisplay &td = (*this)[idx];
 		if (td._active && (td._expire >= 0)) {
diff --git a/engines/mads/messages.h b/engines/mads/messages.h
index 2b673a8a4d..ced8c5bb6d 100644
--- a/engines/mads/messages.h
+++ b/engines/mads/messages.h
@@ -170,7 +170,7 @@ public:
 	 * Draw any text in the list to the specified surface
 	 * @param surface	Surface
 	 */
-	void draw(MSurface *s);
+	void draw(BaseSurface *s);
 
 	/**
 	 * Determine dirty areas for active text areas
diff --git a/engines/mads/msurface.cpp b/engines/mads/msurface.cpp
index 40c69c0f08..8ea9c39bf5 100644
--- a/engines/mads/msurface.cpp
+++ b/engines/mads/msurface.cpp
@@ -30,9 +30,9 @@
 
 namespace MADS {
 
-MADSEngine *MSurface::_vm = nullptr;
+MADSEngine *BaseSurface::_vm = nullptr;
 
-int MSurface::scaleValue(int value, int scale, int err) {
+int BaseSurface::scaleValue(int value, int scale, int err) {
 	int scaled = 0;
 	while (value--) {
 		err -= scale;
@@ -44,7 +44,7 @@ int MSurface::scaleValue(int value, int scale, int err) {
 	return scaled;
 }
 
-void MSurface::drawSprite(const Common::Point &pt, SpriteInfo &info, const Common::Rect &clipRect) {
+void BaseSurface::drawSprite(const Common::Point &pt, SpriteInfo &info, const Common::Rect &clipRect) {
 	enum {
 		kStatusSkip,
 		kStatusScale,
@@ -171,7 +171,7 @@ void MSurface::drawSprite(const Common::Point &pt, SpriteInfo &info, const Commo
 	delete[] scaledLineBuf;
 }
 
-void MSurface::scrollX(int xAmount) {
+void BaseSurface::scrollX(int xAmount) {
 	if (xAmount == 0)
 		return;
 
@@ -203,7 +203,7 @@ void MSurface::scrollX(int xAmount) {
 	markAllDirty();
 }
 
-void MSurface::scrollY(int yAmount) {
+void BaseSurface::scrollY(int yAmount) {
 	if (yAmount == 0)
 		return;
 
@@ -238,7 +238,7 @@ void MSurface::scrollY(int yAmount) {
 	delete[] tempData;
 }
 
-void MSurface::translate(Common::Array<RGB6> &palette) {
+void BaseSurface::translate(Common::Array<RGB6> &palette) {
 	for (int y = 0; y < this->h; ++y) {
 		byte *pDest = (byte *)getBasePtr(0, y);
 
@@ -251,7 +251,7 @@ void MSurface::translate(Common::Array<RGB6> &palette) {
 	markAllDirty();
 }
 
-void MSurface::translate(byte map[PALETTE_COUNT]) {
+void BaseSurface::translate(byte map[PALETTE_COUNT]) {
 	for (int y = 0; y < this->h; ++y) {
 		byte *pDest = (byte *)getBasePtr(0, y);
 
@@ -263,7 +263,7 @@ void MSurface::translate(byte map[PALETTE_COUNT]) {
 	markAllDirty();
 }
 
-MSurface *MSurface::flipHorizontal() const {
+BaseSurface *BaseSurface::flipHorizontal() const {
 	MSurface *dest = new MSurface(this->w, this->h);
 
 	for (int y = 0; y < this->h; ++y) {
@@ -277,7 +277,7 @@ MSurface *MSurface::flipHorizontal() const {
 	return dest;
 }
 
-void MSurface::copyRectTranslate(MSurface &srcSurface, const byte *paletteMap,
+void BaseSurface::copyRectTranslate(BaseSurface &srcSurface, const byte *paletteMap,
 		const Common::Point &destPos, const Common::Rect &srcRect) {
 	// Loop through the lines
 	for (int yCtr = 0; yCtr < srcRect.height(); ++yCtr) {
@@ -294,7 +294,7 @@ void MSurface::copyRectTranslate(MSurface &srcSurface, const byte *paletteMap,
 		destPos.y + srcRect.height()));
 }
 
-void MSurface::copyFrom(MSurface &src, const Common::Point &destPos, int depth,
+void BaseSurface::copyFrom(BaseSurface &src, const Common::Point &destPos, int depth,
 	DepthSurface *depthSurface, int scale, bool flipped, int transparentColor) {
 	int destX = destPos.x, destY = destPos.y;
 	int frameWidth = src.w;
@@ -337,15 +337,13 @@ void MSurface::copyFrom(MSurface &src, const Common::Point &destPos, int depth,
 		if (destX < 0) {
 			copyRect.left += -destX;
 			destX = 0;
-		}
-		else if (destX + copyRect.width() > w) {
+		} else if (destX + copyRect.width() > w) {
 			copyRect.right -= destX + copyRect.width() - w;
 		}
 		if (destY < 0) {
 			copyRect.top += -destY;
 			destY = 0;
-		}
-		else if (destY + copyRect.height() > h) {
+		} else if (destY + copyRect.height() > h) {
 			copyRect.bottom -= destY + copyRect.height() - h;
 		}
 
diff --git a/engines/mads/msurface.h b/engines/mads/msurface.h
index e92770900d..733a29d9e3 100644
--- a/engines/mads/msurface.h
+++ b/engines/mads/msurface.h
@@ -25,7 +25,7 @@
 
 #include "common/scummsys.h"
 #include "common/rect.h"
-#include "graphics/managed_surface.h"
+#include "graphics/screen.h"
 #include "mads/palette.h"
 
 namespace MADS {
@@ -48,9 +48,11 @@ struct SpriteInfo {
 };
 
 /*
- * MADS graphics surface
+ * Base MADS surface class. This derivces from Graphics::Screen
+ * because it has logic we'll need for our own Screen class that
+ * derives from this one
  */
-class MSurface : virtual public Graphics::ManagedSurface {
+class BaseSurface : public Graphics::Screen {
 private:
 	/**
 	 * Helper method for calculating new dimensions when scaling a sprite
@@ -72,17 +74,17 @@ public:
 	/**
 	 * Basic constructor
 	 */
-	MSurface() : Graphics::ManagedSurface() {}
+	BaseSurface() : Graphics::Screen() {}
 
 	/**
 	 * Constructor for a surface with fixed dimensions
 	 */
-	MSurface(int width, int height) : Graphics::ManagedSurface(width, height) {}
+	BaseSurface(int width, int height) : Graphics::Screen(width, height) {}
 
 	/**
 	 * Destructor
 	 */
-	virtual ~MSurface() {}
+	virtual ~BaseSurface() {}
 
 	/**
 	 * Return a rect containing the bounds of the surface
@@ -142,13 +144,13 @@ public:
 	/**
 	 * Create a new surface which is a flipped horizontal copy of the current one
 	 */
-	MSurface *flipHorizontal() const;
+	BaseSurface *flipHorizontal() const;
 
 	/**
 	 * Copy an area from one surface to another, translating it using a palette
 	 * map as it's done
 	 */
-	void copyRectTranslate(MSurface &srcSurface, const byte *paletteMap,
+	void copyRectTranslate(BaseSurface &srcSurface, const byte *paletteMap,
 		const Common::Point &destPos, const Common::Rect &srcRect);
 
 	/**
@@ -161,10 +163,22 @@ public:
 	 * @param flipped		Flag for whether image is to be flipped
 	 * @param transparentColor	Transparency palette index
 	 */
-	void copyFrom(MSurface &src, const Common::Point &destPos, int depth, DepthSurface *depthSurface,
+	void copyFrom(BaseSurface &src, const Common::Point &destPos, int depth, DepthSurface *depthSurface,
 		int scale, bool flipped, int transparentColor = -1);
 };
 
+class MSurface : public BaseSurface {
+protected:
+	/**
+	 * Override the addDirtyRect from Graphics::Screen, since for standard
+	 * surfaces we don't need dirty rects to be tracked
+	 */
+	virtual void addDirtyRect(const Common::Rect &r) {}
+public:
+	MSurface() : BaseSurface() {}
+	MSurface(int width, int height) : BaseSurface(width, height) {}
+};
+
 class DepthSurface : public MSurface {
 public:
 	/**
diff --git a/engines/mads/nebular/nebular_scenes.cpp b/engines/mads/nebular/nebular_scenes.cpp
index 40228b4b7d..9502d273ea 100644
--- a/engines/mads/nebular/nebular_scenes.cpp
+++ b/engines/mads/nebular/nebular_scenes.cpp
@@ -311,7 +311,7 @@ Common::String NebularScene::formAnimName(char sepChar, int suffixNum) {
 
 /*------------------------------------------------------------------------*/
 
-void SceneInfoNebular::loadCodes(MSurface &depthSurface, int variant) {
+void SceneInfoNebular::loadCodes(BaseSurface &depthSurface, int variant) {
 	File f(Resources::formatName(RESPREFIX_RM, _sceneId, ".DAT"));
 	MadsPack codesPack(&f);
 	Common::SeekableReadStream *stream = codesPack.getItemStream(variant + 1);
@@ -322,7 +322,7 @@ void SceneInfoNebular::loadCodes(MSurface &depthSurface, int variant) {
 	f.close();
 }
 
-void SceneInfoNebular::loadCodes(MSurface &depthSurface, Common::SeekableReadStream *stream) {
+void SceneInfoNebular::loadCodes(BaseSurface &depthSurface, Common::SeekableReadStream *stream) {
 	byte *destP = (byte *)depthSurface.getPixels();
 	byte *endP = (byte *)depthSurface.getBasePtr(0, depthSurface.h);
 
diff --git a/engines/mads/nebular/nebular_scenes.h b/engines/mads/nebular/nebular_scenes.h
index 58a6d1c98f..b600c6dbe1 100644
--- a/engines/mads/nebular/nebular_scenes.h
+++ b/engines/mads/nebular/nebular_scenes.h
@@ -1373,9 +1373,9 @@ public:
 class SceneInfoNebular : public SceneInfo {
 	friend class SceneInfo;
 protected:
-	virtual void loadCodes(MSurface &depthSurface, int variant);
+	virtual void loadCodes(BaseSurface &depthSurface, int variant);
 
-	virtual void loadCodes(MSurface &depthSurface, Common::SeekableReadStream *stream);
+	virtual void loadCodes(BaseSurface &depthSurface, Common::SeekableReadStream *stream);
 
 	/**
 	* Constructor
diff --git a/engines/mads/phantom/phantom_scenes.cpp b/engines/mads/phantom/phantom_scenes.cpp
index 7ef627ceeb..bfb521e369 100644
--- a/engines/mads/phantom/phantom_scenes.cpp
+++ b/engines/mads/phantom/phantom_scenes.cpp
@@ -174,7 +174,7 @@ Common::String PhantomScene::formAnimName(char sepChar, int suffixNum) {
 
 /*------------------------------------------------------------------------*/
 
-void SceneInfoPhantom::loadCodes(MSurface &depthSurface, int variant) {
+void SceneInfoPhantom::loadCodes(BaseSurface &depthSurface, int variant) {
 	Common::String ext = Common::String::format(".WW%d", variant);
 	Common::String fileName = Resources::formatName(RESPREFIX_RM, _sceneId, ext);
 	if (!Common::File::exists(fileName))
@@ -190,7 +190,7 @@ void SceneInfoPhantom::loadCodes(MSurface &depthSurface, int variant) {
 	f.close();
 }
 
-void SceneInfoPhantom::loadCodes(MSurface &depthSurface, Common::SeekableReadStream *stream) {
+void SceneInfoPhantom::loadCodes(BaseSurface &depthSurface, Common::SeekableReadStream *stream) {
 	byte *destP = (byte *)depthSurface.getPixels();
 	byte *walkMap = new byte[stream->size()];
 	stream->read(walkMap, stream->size());
diff --git a/engines/mads/phantom/phantom_scenes.h b/engines/mads/phantom/phantom_scenes.h
index a6a8395a2c..6b7ab697f3 100644
--- a/engines/mads/phantom/phantom_scenes.h
+++ b/engines/mads/phantom/phantom_scenes.h
@@ -474,9 +474,9 @@ public:
 class SceneInfoPhantom : public SceneInfo {
 	friend class SceneInfo;
 protected:
-	virtual void loadCodes(MSurface &depthSurface, int variant);
+	virtual void loadCodes(BaseSurface &depthSurface, int variant);
 
-	virtual void loadCodes(MSurface &depthSurface, Common::SeekableReadStream *stream);
+	virtual void loadCodes(BaseSurface &depthSurface, Common::SeekableReadStream *stream);
 
 	/**
 	* Constructor
diff --git a/engines/mads/scene_data.cpp b/engines/mads/scene_data.cpp
index 5323178ec7..21fd4f9026 100644
--- a/engines/mads/scene_data.cpp
+++ b/engines/mads/scene_data.cpp
@@ -128,7 +128,7 @@ SceneInfo *SceneInfo::init(MADSEngine *vm) {
 }
 
 void SceneInfo::load(int sceneId, int variant, const Common::String &resName,
-		int flags, DepthSurface &depthSurface, MSurface &bgSurface) {
+		int flags, DepthSurface &depthSurface, BaseSurface &bgSurface) {
 	bool sceneFlag = sceneId >= 0;
 
 	// Figure out the resource to use
@@ -299,7 +299,7 @@ void SceneInfo::load(int sceneId, int variant, const Common::String &resName,
 	}
 }
 
-void SceneInfo::loadPalette(int sceneId, int artFileNum, const Common::String &resName, int flags, MSurface &bgSurface) {
+void SceneInfo::loadPalette(int sceneId, int artFileNum, const Common::String &resName, int flags, BaseSurface &bgSurface) {
 	bool sceneFlag = sceneId >= 0;
 	Common::String resourceName;
 	bool isV2 = (_vm->getGameID() != GType_RexNebular);
@@ -351,7 +351,7 @@ void SceneInfo::loadPalette(int sceneId, int artFileNum, const Common::String &r
 	}
 }
 
-void SceneInfo::loadMadsV1Background(int sceneId, const Common::String &resName, int flags, MSurface &bgSurface) {
+void SceneInfo::loadMadsV1Background(int sceneId, const Common::String &resName, int flags, BaseSurface &bgSurface) {
 	bool sceneFlag = sceneId >= 0;
 	Common::String resourceName;
 	Common::SeekableReadStream *stream;
@@ -397,7 +397,7 @@ void SceneInfo::loadMadsV1Background(int sceneId, const Common::String &resName,
 	artFile.close();
 }
 
-void SceneInfo::loadMadsV2Background(int sceneId, const Common::String &resName, int flags, MSurface &bgSurface) {
+void SceneInfo::loadMadsV2Background(int sceneId, const Common::String &resName, int flags, BaseSurface &bgSurface) {
 	Common::String tileMapResourceName = Resources::formatName(RESPREFIX_RM, sceneId, ".MM");
 	File tileMapFile(tileMapResourceName);
 	MadsPack tileMapPack(&tileMapFile);
diff --git a/engines/mads/scene_data.h b/engines/mads/scene_data.h
index 41a08f74eb..a28c42c5ab 100644
--- a/engines/mads/scene_data.h
+++ b/engines/mads/scene_data.h
@@ -189,36 +189,36 @@ public:
 	 * loads the data
 	 */
 	void load(int sceneId, int variant, const Common::String &resName, int flags,
-		DepthSurface &depthSurface, MSurface &bgSurface);
+		DepthSurface &depthSurface, BaseSurface &bgSurface);
 
 	/**
 	 * Loads the palette for a scene
 	 */
-	void loadPalette(int sceneId, int artFileNum, const Common::String &resName, int flags, MSurface &bgSurface);
+	void loadPalette(int sceneId, int artFileNum, const Common::String &resName, int flags, BaseSurface &bgSurface);
 
 	/**
 	 * Loads a V1 game background
 	 */
-	void loadMadsV1Background(int sceneId, const Common::String &resName, int flags, MSurface &bgSurface);
+	void loadMadsV1Background(int sceneId, const Common::String &resName, int flags, BaseSurface &bgSurface);
 
 	/**
 	 * Loads a V2 game background
 	 */
-	void loadMadsV2Background(int sceneId, const Common::String &resName, int flags, MSurface &bgSurface);
+	void loadMadsV2Background(int sceneId, const Common::String &resName, int flags, BaseSurface &bgSurface);
 
 	/**
 	 * Loads the given surface with depth information of a given scene
 	 * @param depthSurface	Depth/walk surface
 	 * @param variant		Variant number to load
 	 */
-	virtual void loadCodes(MSurface &depthSurface, int variant) = 0;
+	virtual void loadCodes(BaseSurface &depthSurface, int variant) = 0;
 
 	/**
 	 * Loads the given surface with depth information of a given scene
 	 * @param depthSurface	Depth/walk surface
 	 * @param stream		Stream to load the data from
 	 */
-	virtual void loadCodes(MSurface &depthSurface, Common::SeekableReadStream *stream) = 0;
+	virtual void loadCodes(BaseSurface &depthSurface, Common::SeekableReadStream *stream) = 0;
 };
 
 } // End of namespace MADS
diff --git a/engines/mads/screen.cpp b/engines/mads/screen.cpp
index 05f9de61e2..b17b6e93b8 100644
--- a/engines/mads/screen.cpp
+++ b/engines/mads/screen.cpp
@@ -201,7 +201,7 @@ void DirtyAreas::mergeAreas(int idx1, int idx2) {
 	da1._textActive = true;
 }
 
-void DirtyAreas::copy(MSurface *srcSurface, MSurface *destSurface, const Common::Point &posAdjust) {
+void DirtyAreas::copy(BaseSurface *srcSurface, BaseSurface *destSurface, const Common::Point &posAdjust) {
 	for (uint i = 0; i < size(); ++i) {
 		const Common::Rect &srcBounds = (*this)[i]._bounds;
 
@@ -555,7 +555,7 @@ void ScreenObjects::synchronize(Common::Serializer &s) {
 
 /*------------------------------------------------------------------------*/
 
-Screen::Screen(): Graphics::Screen(), MSurface() {
+Screen::Screen(): BaseSurface() {
 	// Create the screen surface separately on another surface, since the screen
 	// surface will be subject to change as the clipping area is altered
 	_rawSurface.create(MADS_SCREEN_WIDTH, MADS_SCREEN_HEIGHT);
diff --git a/engines/mads/screen.h b/engines/mads/screen.h
index 626080580e..eeb15453f8 100644
--- a/engines/mads/screen.h
+++ b/engines/mads/screen.h
@@ -25,7 +25,6 @@
 
 #include "common/scummsys.h"
 #include "common/array.h"
-#include "graphics/screen.h"
 #include "mads/msurface.h"
 #include "mads/action.h"
 
@@ -118,7 +117,7 @@ public:
 	* @param destSurface	Dest surface
 	* @param posAdjust		Position adjustment
 	*/
-	void copy(MSurface *srcSurface, MSurface *destSurface, const Common::Point &posAdjust);
+	void copy(BaseSurface *srcSurface, BaseSurface *destSurface, const Common::Point &posAdjust);
 
 	/**
 	* Use the lsit of dirty areas to copy areas of the screen surface to
@@ -129,7 +128,6 @@ public:
 	void reset();
 };
 
-
 class ScreenObject {
 public:
 	bool _active;
@@ -208,7 +206,7 @@ public:
 	void synchronize(Common::Serializer &s);
 };
 
-class Screen : virtual public Graphics::Screen, virtual public MSurface {
+class Screen : public BaseSurface {
 private:
 	uint16 _random;
 	MSurface _rawSurface;
diff --git a/engines/mads/sprites.cpp b/engines/mads/sprites.cpp
index fc8ddf22d2..84060ccdfe 100644
--- a/engines/mads/sprites.cpp
+++ b/engines/mads/sprites.cpp
@@ -337,7 +337,7 @@ void SpriteSlots::drawSprites(MSurface *s) {
 				s->copyFrom(*sprite, Common::Point(xp, yp), slot._depth, &scene._depthSurface,
 					-1, flipped, sprite->getTransparencyIndex());
 			} else {
-				MSurface *spr = sprite;
+				BaseSurface *spr = sprite;
 				if (flipped) {
 					// Create a flipped copy of the sprite temporarily
 					spr = sprite->flipHorizontal();
diff --git a/engines/mads/user_interface.cpp b/engines/mads/user_interface.cpp
index 8f7cb0a24b..204f71fe43 100644
--- a/engines/mads/user_interface.cpp
+++ b/engines/mads/user_interface.cpp
@@ -161,7 +161,7 @@ void UISlots::draw(bool updateFlag, bool delFlag) {
 					MSprite *sprite = asset->getFrame(frameNumber - 1);
 
 					if (flipped) {
-						MSurface *spr = sprite->flipHorizontal();
+						BaseSurface *spr = sprite->flipHorizontal();
 						userInterface.mergeFrom(spr, spr->getBounds(), slot._position,
 							sprite->getTransparencyIndex());
 						spr->free();
@@ -429,7 +429,7 @@ void UserInterface::drawTextElements() {
 	}
 }
 
-void UserInterface::mergeFrom(MSurface *src, const Common::Rect &srcBounds,
+void UserInterface::mergeFrom(BaseSurface *src, const Common::Rect &srcBounds,
 	const Common::Point &destPos, int transparencyIndex) {
 	// Validation of the rectangle and position
 	int destX = destPos.x, destY = destPos.y;
diff --git a/engines/mads/user_interface.h b/engines/mads/user_interface.h
index 9232dc1bb1..6c9485998a 100644
--- a/engines/mads/user_interface.h
+++ b/engines/mads/user_interface.h
@@ -238,7 +238,7 @@ public:
 	* @param destPos		Destination position to draw in current surface
 	* @param transparencyIndex	Transparency color
 	*/
-	void mergeFrom(MSurface *src, const Common::Rect &srcBounds, const Common::Point &destPos,
+	void mergeFrom(BaseSurface *src, const Common::Rect &srcBounds, const Common::Point &destPos,
 		int transparencyIndex = -1);
 
 	/**