third_party/WebKit/Source/core/layout/ScrollAlignment.h

   1 /*
   2  * Copyright (C) 2003, 2009 Apple Inc.  All rights reserved.
   3  *
   4  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
   5  *
   6  * Other contributors:
   7  *   Robert O'Callahan <roc+@cs.cmu.edu>
   8  *   David Baron <dbaron@fas.harvard.edu>
   9  *   Christian Biesinger <cbiesinger@web.de>
  10  *   Randall Jesup <rjesup@wgate.com>
  11  *   Roland Mainz <roland.mainz@informatik.med.uni-giessen.de>
  12  *   Josh Soref <timeless@mac.com>
  13  *   Boris Zbarsky <bzbarsky@mit.edu>
  14  *
  15  * This library is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU Lesser General Public
  17  * License as published by the Free Software Foundation; either
  18  * version 2.1 of the License, or (at your option) any later version.
  19  *
  20  * This library is distributed in the hope that it will be useful,
  21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  23  * Lesser General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU Lesser General Public
  26  * License along with this library; if not, write to the Free Software
  27  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  28  *
  29  * Alternatively, the contents of this file may be used under the terms
  30  * of either the Mozilla Public License Version 1.1, found at
  31  * http://www.mozilla.org/MPL/ (the "MPL") or the GNU General Public
  32  * License Version 2.0, found at http://www.fsf.org/copyleft/gpl.html
  33  * (the "GPL"), in which case the provisions of the MPL or the GPL are
  34  * applicable instead of those above.  If you wish to allow use of your
  35  * version of this file only under the terms of one of those two
  36  * licenses (the MPL or the GPL) and not to allow others to use your
  37  * version of this file under the LGPL, indicate your decision by
  38  * deletingthe provisions above and replace them with the notice and
  39  * other provisions required by the MPL or the GPL, as the case may be.
  40  * If you do not delete the provisions above, a recipient may use your
  41  * version of this file under any of the LGPL, the MPL or the GPL.
  42  */
  43
  44 #ifndef ScrollAlignment_h
  45 #define ScrollAlignment_h
  46
  47 #include "core/CoreExport.h"
  48 #include "wtf/Allocator.h"
  49
  50 namespace blink {
  51
  52 enum ScrollAlignmentBehavior {
  53     ScrollAlignmentNoScroll,
  54     ScrollAlignmentCenter,
  55     ScrollAlignmentTop,
  56     ScrollAlignmentBottom,
  57     ScrollAlignmentLeft,
  58     ScrollAlignmentRight,
  59     ScrollAlignmentClosestEdge
  60 };
  61
  62 class LayoutRect;
  63
  64 struct CORE_EXPORT ScrollAlignment {
  65     STACK_ALLOCATED();
  66     static ScrollAlignmentBehavior getVisibleBehavior(const ScrollAlignment& s) { return s.m_rectVisible; }
  67     static ScrollAlignmentBehavior getPartialBehavior(const ScrollAlignment& s) { return s.m_rectPartial; }
  68     static ScrollAlignmentBehavior getHiddenBehavior(const ScrollAlignment& s) { return s.m_rectHidden; }
  69
  70     // FIXME: This function should probably go somewhere else but where?
  71     static LayoutRect getRectToExpose(const LayoutRect& visibleRect, const LayoutRect& exposeRect, const ScrollAlignment& alignX, const ScrollAlignment& alignY);
  72
  73     static const ScrollAlignment alignCenterIfNeeded;
  74     static const ScrollAlignment alignToEdgeIfNeeded;
  75     static const ScrollAlignment alignCenterAlways;
  76     static const ScrollAlignment alignTopAlways;
  77     static const ScrollAlignment alignBottomAlways;
  78
  79     ScrollAlignmentBehavior m_rectVisible;
  80     ScrollAlignmentBehavior m_rectHidden;
  81     ScrollAlignmentBehavior m_rectPartial;
  82 };
  83
  84
  85 } // namespace blink
  86
  87 #endif // ScrollAlignment_h