(libinterface) Add 'square' scaling option to BitmapView

When toggled, this option disallows the scaled-to view rect being
uneven.

application/views/ConversationView.cpp

@@ -286,6 +286,7 @@ ConversationView::_InitInterface()
 	fIcon->SetExplicitMinSize(BSize(50, 50));
 	fIcon->SetExplicitPreferredSize(BSize(50, 50));
 	fIcon->SetExplicitAlignment(BAlignment(B_ALIGN_RIGHT, B_ALIGN_MIDDLE));
+	fIcon->SetSquare(true);
 
 	fProtocolView = new BitmapView("protocolView");
 

libs/libinterface/BitmapView.cpp

@@ -22,6 +22,7 @@ BitmapView::BitmapView(const char* name, uint32 flags)
 	:
 	BView(name, flags | B_WILL_DRAW | B_FULL_UPDATE_ON_RESIZE),
 	fBitmap(NULL),
+	fIsSquare(false),
 	fWidth(kMinWidth),
 	fHeight(kMinHeight)
 {
@@ -97,6 +98,13 @@ BitmapView::SetBitmap(const BBitmap* bitmap)
 }
 
 
+void
+BitmapView::SetSquare(bool isSquare)
+{
+	fIsSquare = isSquare;
+}
+
+
 BSize
 BitmapView::MinSize()
 {
@@ -131,5 +139,30 @@ BitmapView::Draw(BRect frame)
 	SetBlendingMode(B_PIXEL_ALPHA, B_ALPHA_OVERLAY);
 
 	DrawBitmap(fBitmap, fBitmap->Bounds(),
-		Bounds(), B_FILTER_BITMAP_BILINEAR);
+		_ViewBounds(), B_FILTER_BITMAP_BILINEAR);
+}
+
+
+BRect
+BitmapView::_ViewBounds()
+{
+	BRect bounds = Bounds();
+	if (fIsSquare == false || bounds.Height() == bounds.Width())
+		return bounds;
+
+	BPoint lt = bounds.LeftTop();
+	BPoint rb = bounds.RightBottom();
+	float diff = 0.0;
+
+	if (bounds.Height() > bounds.Width()) {
+		diff = bounds.Height() - bounds.Width();
+		lt -= BPoint(0.0, diff / 2);
+		rb += BPoint(0.0, diff / 2);
+	}
+	else if (bounds.Width() > bounds.Height()) {
+		diff = bounds.Height() - bounds.Width();
+		lt -= BPoint(diff / 2, 0.0);
+		rb += BPoint(diff / 2, 0.0);
+	}
+	return BRect(lt, rb);
 }

libs/libinterface/BitmapView.h

@@ -23,6 +23,7 @@ public:
 
 				status_t	SetBitmap(const char* filename);
 				status_t	SetBitmap(const BBitmap* bitmap);
+				void		SetSquare(bool isSquare);
 
 	virtual 	BSize		MinSize();
 	virtual 	BSize		MaxSize();
@@ -31,7 +32,10 @@ public:
 	virtual		void		Draw(BRect frame);
 
 private:
+				BRect		_ViewBounds();
+
 				BBitmap*	fBitmap;
+				bool		fIsSquare;
 				float		fWidth;
 				float		fHeight;
 };