6 files changed, 97 insertions, 7 deletions

diff --git a/engines/titanic/direct_draw_surface.cpp b/engines/titanic/direct_draw_surface.cpp
index 6ce6f2411a..cf7639cf1b 100644
--- a/engines/titanic/direct_draw_surface.cpp
+++ b/engines/titanic/direct_draw_surface.cpp
@@ -77,7 +77,13 @@ void DirectDrawSurface::fill(const Common::Rect *bounds, uint32 color) {
 	_surface->fillRect(tempBounds, color);
 }
 
-void DirectDrawSurface::blitFast(const Common::Point &destPos, DirectDrawSurface *srcSurface, Common::Rect *bounds) {
+void DirectDrawSurface::blit(const Common::Rect &destRect, DirectDrawSurface *srcSurface, Common::Rect &srcRect) {
+	assert(srcSurface);
+	if (!destRect.isEmpty())
+		_surface->transBlitFrom(*srcSurface->_surface, srcRect, destRect, (uint)-1);
+}
+
+void DirectDrawSurface::blit(const Common::Point &destPos, DirectDrawSurface *srcSurface, Common::Rect *bounds) {
 	if (bounds)
 		_surface->blitFrom(*srcSurface->_surface, *bounds, destPos);
 	else
diff --git a/engines/titanic/direct_draw_surface.h b/engines/titanic/direct_draw_surface.h
index 14988583f0..9a93316f7d 100644
--- a/engines/titanic/direct_draw_surface.h
+++ b/engines/titanic/direct_draw_surface.h
@@ -102,7 +102,12 @@ public:
 	/**
 	 * Copy data from a source surfcae into this one
 	 */
-	void blitFast(const Common::Point &destPos, DirectDrawSurface *srcSurface, Common::Rect *bounds);
+	void blit(const Common::Rect &destRect, DirectDrawSurface *srcSurface, Common::Rect &srcRect);
+
+	/**
+	 * Copy data from a source surfcae into this one
+	 */
+	void blit(const Common::Point &destPos, DirectDrawSurface *srcSurface, Common::Rect *bounds);
 };
 
 } // End of namespace Titanic
diff --git a/engines/titanic/game_view.cpp b/engines/titanic/game_view.cpp
index 88ad095f7b..ecdeb85f9a 100644
--- a/engines/titanic/game_view.cpp
+++ b/engines/titanic/game_view.cpp
@@ -54,7 +54,7 @@ void CGameView::createSurface(const CResourceKey &key) {
 	// Create a fresh surface
 	CScreenManager::setCurrent();
 	_surface = CScreenManager::_currentScreenManagerPtr->createSurface(key);
-	_surface->_field3C = true;
+	_surface->_blitFlag = true;
 }
 
 void CGameView::draw1() {
diff --git a/engines/titanic/screen_manager.h b/engines/titanic/screen_manager.h
index 8fe51c57b0..ae3424d9fa 100644
--- a/engines/titanic/screen_manager.h
+++ b/engines/titanic/screen_manager.h
@@ -148,7 +148,7 @@ public:
 	/**
 	 * Sets the video mode
 	 */
-	virtual void setMode(int width, int height, int bpp, uint numBackSurfaces, bool flag2) = 0;
+	virtual void setMode(int width, int height, int bpp, uint numBackSurfaces, bool flag2);
 
 	/**
 	 * Handles drawing the cursors
diff --git a/engines/titanic/video_surface.cpp b/engines/titanic/video_surface.cpp
index 503fd6bfc7..b38a8624ea 100644
--- a/engines/titanic/video_surface.cpp
+++ b/engines/titanic/video_surface.cpp
@@ -30,8 +30,8 @@ int CVideoSurface::_videoSurfaceCounter = 0;
 
 CVideoSurface::CVideoSurface(CScreenManager *screenManager) :
 		_screenManager(screenManager), _rawSurface(nullptr),
-		_field34(nullptr), _pendingLoad(false), _field3C(false), _field40(0),
-		_field44(4), _field48(0), _field50(1) {
+		_field34(nullptr), _pendingLoad(false), _blitFlag(false),
+		_field40(0), _field44(4), _field48(0), _field50(1) {
 	_videoSurfaceNum = _videoSurfaceCounter++;
 }
 
@@ -46,6 +46,74 @@ void CVideoSurface::setSurface(CScreenManager *screenManager, DirectDrawSurface
 	_ddSurface = surface;
 }
 
+void CVideoSurface::blitFrom(const Common::Rect &srcRect, const Common::Rect &destRect, CVideoSurface *srcSurface) {
+	// TODO: Cases when _blitFlag is false
+	assert(_blitFlag);
+	error("TODO");
+}
+
+void CVideoSurface::clipBounds(Common::Rect &srcRect, Common::Rect &destRect,
+		CVideoSurface *srcSurface, Common::Rect *subRect, Common::Point *pt) {
+	if (pt) {
+		srcRect.left = pt->x;
+		srcRect.top = pt->y;
+	} else {
+		srcRect.left = srcRect.top = 0;
+	}
+
+	if (subRect) {
+		destRect.right = destRect.left + subRect->width();
+		destRect.bottom = destRect.top + subRect->height();
+		srcRect = *subRect;
+	} else {
+		srcRect.right = srcRect.left + srcSurface->getWidth();
+		srcRect.bottom = srcRect.top + srcSurface->getHeight();
+		srcRect = Common::Rect(0, 0, srcSurface->getWidth(), srcSurface->getHeight());
+	}
+
+	// Clip destination rect to be on-screen
+	if (destRect.left < 0) {
+		srcRect.left -= destRect.left;
+		destRect.left = 0;
+	}
+	if (destRect.top < 0) {
+		srcRect.top -= destRect.top;
+		destRect.top = 0;
+	}
+	if (destRect.right > getWidth()) {
+		srcRect.right += getWidth() - destRect.right;
+		destRect.right = getWidth();
+	}
+	if (destRect.bottom > getHeight()) {
+		srcRect.bottom += getHeight() - destRect.bottom;
+		destRect.bottom = getHeight();
+	}
+
+	// Clip source rect to be within the source surface
+	if (srcRect.left < 0) {
+		destRect.left -= srcRect.left;
+		srcRect.left = 0;
+	}
+	if (srcRect.top < 0) {
+		destRect.top -= srcRect.top;
+		srcRect.top = 0;
+	}
+	if (srcRect.right > srcSurface->getWidth()) {
+		destRect.right += srcSurface->getWidth() - srcRect.right;
+		srcRect.right = srcSurface->getWidth();
+	}
+	if (srcRect.bottom > srcSurface->getHeight()) {
+		destRect.bottom += srcSurface->getHeight() - srcRect.bottom;
+		srcRect.bottom = srcSurface->getHeight();
+	}
+
+	// Validate that the resulting rects are valid
+	if (destRect.left >= destRect.right || destRect.top >= destRect.bottom
+		|| srcRect.left >= srcRect.right || srcRect.top >= srcRect.bottom)
+		error("Invalid rect");
+}
+
+
 /*------------------------------------------------------------------------*/
 
 OSVideoSurface::OSVideoSurface(CScreenManager *screenManager, DirectDrawSurface *surface) :
diff --git a/engines/titanic/video_surface.h b/engines/titanic/video_surface.h
index 7efd8b5c37..88ab2e4d45 100644
--- a/engines/titanic/video_surface.h
+++ b/engines/titanic/video_surface.h
@@ -39,6 +39,12 @@ class CTargaDecode;
 class CVideoSurface : public ListItem {
 	friend class CJPEGDecode;
 	friend class CTargaDecode;
+private:
+	/**
+	 * Calculates blitting bounds
+	 */
+	void clipBounds(Common::Rect &destRect, Common::Rect &srcRect,
+		CVideoSurface *srcSurface, Common::Rect *bounds2, Common::Point *pt);
 protected:
 	static int _videoSurfaceCounter;
 protected:
@@ -55,7 +61,7 @@ protected:
 	int _field50;
 	int _lockCount;
 public:
-	bool _field3C;
+	bool _blitFlag;
 public:
 	CVideoSurface(CScreenManager *screenManager);
 	virtual ~CVideoSurface();
@@ -141,6 +147,11 @@ public:
 	 * Frees the underlying surface
 	 */
 	virtual int freeSurface() { return 0; }
+
+	/**
+	 * Blit from another surface
+	 */
+	void blitFrom(const Common::Rect &srcRect, const Common::Rect &destRect, CVideoSurface *srcSurface);
 };
 
 class OSVideoSurface : public CVideoSurface {