TITANIC: Fixes for correct positioning of view background

engines/titanic/game_manager.cpp

@@ -239,7 +239,7 @@ void CGameManager::extendBounds(const Rect &r) {
 	if (_bounds.isEmpty())
 		_bounds = r;
 	else
-		_bounds.combine1(r);
+		_bounds.combine(r);
 }
 
 } // End of namespace Titanic

engines/titanic/game_view.cpp

@@ -27,6 +27,9 @@
 
 namespace Titanic {
 
+#define VIEW_OFFSET_X 20
+#define VIEW_OFFSET_Y 10
+
 CGameView::CGameView() : _gameManager(nullptr), _surface(nullptr) {
 }
 
@@ -62,10 +65,10 @@ void CGameView::drawView() {
 	Rect srcRect = _gameManager->_bounds;
 
 	Rect rect2(0, 0, 600, 340);
-	rect2.translate(20, 10);
-	srcRect.combine2(rect2);
-	srcRect.translate(-20, -10);
+	rect2.translate(VIEW_OFFSET_X, VIEW_OFFSET_Y);
+	srcRect.constrain(rect2);
 	Common::Point destPos(srcRect.left, srcRect.top);
+	srcRect.translate(-VIEW_OFFSET_X, -VIEW_OFFSET_Y);
 
 	CScreenManager::_currentScreenManagerPtr->blitFrom(SURFACE_BACKBUFFER,
 		_surface, &destPos, &srcRect);

engines/titanic/rect.cpp

@@ -24,19 +24,19 @@
 
 namespace Titanic {
 
-void Rect::combine1(const Rect &r) {
+void Rect::combine(const Rect &r) {
 	if (isEmpty() || r.isEmpty())
 		return;
 
 	Common::Rect::extend(r);
 }
 
-void Rect::combine2(const Rect &r) {
+void Rect::constrain(const Rect &r) {
 	if (!isEmpty()) {
 		if (r.isEmpty()) {
 			clear();
 		} else {
-			Common::Rect::extend(r);
+			Common::Rect::clip(r);
 		}
 	}
 }

engines/titanic/rect.h

@@ -48,12 +48,12 @@ public:
 	/**
 	 * Combine another rect into this one
 	 */
-	void combine1(const Rect &r);
+	void combine(const Rect &r);
 
 	/**
-	 * Combine another rect into this one
+	 * Constrains/clips to the intersection area of the given rect
 	 */
-	void combine2(const Rect &r);
+	void constrain(const Rect &r);
 };
 
 } // End of namespace Titanic

engines/titanic/screen_manager.cpp

@@ -149,7 +149,7 @@ void OSScreenManager::blitFrom(SurfaceNum surfaceNum, CVideoSurface *src,
 		rect2 = srcBounds;
 		rect2.translate(-srcBounds.left, -srcBounds.top);
 		rect2.translate(destPoint.x, destPoint.y);
-		rect2.combine2(_backSurfaces[surfaceNum]._bounds);
+		rect2.constrain(_backSurfaces[surfaceNum]._bounds);
 
 		rect2.translate(-destPoint.x, -destPoint.y);
 		rect2.translate(srcBounds.left, srcBounds.top);

engines/titanic/video_surface.cpp

@@ -59,12 +59,14 @@ void CVideoSurface::blitFrom(const Point &destPos, CVideoSurface *src, const Rec
 }
 
 void CVideoSurface::clipBounds(Rect &srcRect, Rect &destRect,
-		CVideoSurface *srcSurface, const Rect *subRect, const Point *pt) {
-	if (pt) {
-		srcRect.left = pt->x;
-		srcRect.top = pt->y;
+		CVideoSurface *srcSurface, const Rect *subRect, const Point *destPos) {
+	// Figure out initial source rect and dest rect, based on whether
+	// specific subRect and/or destPos have been passed
+	if (destPos) {
+		destRect.left = destPos->x;
+		destRect.top = destPos->y;
 	} else {
-		srcRect.left = srcRect.top = 0;
+		destRect.left = destRect.top = 0;
 	}
 
 	if (subRect) {
@@ -124,8 +126,7 @@ void CVideoSurface::blitRect1(const Rect &srcRect, const Rect &destRect, CVideoS
 	lock();
 
 	// TODO: Do it like the original does it
-//	this->_rawSurface->blitFrom(*src->_rawSurface, srcRect, Point(destRect.left, destRect.top));
-	this->_rawSurface->blitFrom(*src->_rawSurface);
+	_rawSurface->blitFrom(*src->_rawSurface, srcRect, Point(destRect.left, destRect.top));
 
 	src->unlock();
 	unlock();

engines/titanic/video_surface.h

@@ -44,8 +44,8 @@ private:
 	/**
 	 * Calculates blitting bounds
 	 */
-	void clipBounds(Rect &srcRect, Rect &destRect,
-		CVideoSurface *srcSurface, const Rect *subRect, const Point *pt);
+	void clipBounds(Rect &srcRect, Rect &destRect, CVideoSurface *srcSurface,
+		const Rect *subRect = nullptr, const Point *destPos = nullptr);
 
 	void blitRect1(const Rect &srcRect, const Rect &destRect, CVideoSurface *src);
 	void blitRect2(const Rect &srcRect, const Rect &destRect, CVideoSurface *src);