Added MoveIntoFrame() method.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39494 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/interface/LayoutUtils.h

@@ -35,6 +35,7 @@ public:
 	static	BRect				AlignInFrame(BRect frame, BSize maxSize,
 									BAlignment alignment);
 	static	void				AlignInFrame(BView* view, BRect frame);
+	static	BRect				MoveIntoFrame(BRect rect, BSize maxSize);
 };
 
 #endif	//	_LAYOUT_UTILS_H

src/kits/interface/LayoutUtils.cpp

@@ -1,6 +1,6 @@
 /*
- * Copyright 2006, Ingo Weinhold <[email protected].de>.
- * All rights reserved. Distributed under the terms of the MIT License.
+ * Copyright 2006-2010, Ingo Weinhold, ingo_weinhold@gmx.de.
+ * Distributed under the terms of the MIT License.
  */
 
 #include <LayoutUtils.h>
@@ -199,3 +199,34 @@ BLayoutUtils::AlignInFrame(BView* view, BRect frame)
  	view->ResizeTo(frame.Size());
 }
 
+
+/*!	Offsets a rectangle's location so that it lies fully in a given rectangular
+	frame.
+
+	If the rectangle is too wide/high to fully fit in the frame, its left/top
+	edge is offset to 0. The rect's size always remains unchanged.
+
+	\param rect The rectangle to be moved.
+	\param frameSize The size of the frame the rect shall be moved into. The
+		frame's left-top is (0, 0).
+	\return The modified rect.
+*/
+/*static*/ BRect
+BLayoutUtils::MoveIntoFrame(BRect rect, BSize frameSize)
+{
+	BPoint leftTop(rect.LeftTop());
+
+	// enforce horizontal limits; favor left edge
+	if (rect.right > frameSize.width)
+		leftTop.x -= rect.right - frameSize.width;
+	if (rect.left < 0)
+		leftTop.x = 0;
+
+	// enforce vertical limits; favor top edge
+	if (rect.bottom > frameSize.height)
+		leftTop.y -= rect.bottom - frameSize.height;
+	if (rect.top < 0)
+		leftTop.y = 0;
+
+	return rect.OffsetToSelf(leftTop);
+}