ColumnInfo.h revision cad810f21b803229eb11403f9209855525a25d57 
1/*
2 * Copyright (C) 2010 Apple Inc.  All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef ColumnInfo_h
27#define ColumnInfo_h
28
29#include <wtf/Vector.h>
30#include "IntRect.h"
31
32namespace WebCore {
33
34class ColumnInfo : public Noncopyable {
35public:
36    ColumnInfo()
37        : m_desiredColumnWidth(0)
38        , m_desiredColumnCount(1)
39        , m_columnCount(1)
40        , m_columnHeight(0)
41        , m_minimumColumnHeight(0)
42        , m_forcedBreaks(0)
43        , m_maximumDistanceBetweenForcedBreaks(0)
44        , m_forcedBreakOffset(0)
45        { }
46
47    int desiredColumnWidth() const { return m_desiredColumnWidth; }
48    void setDesiredColumnWidth(int width) { m_desiredColumnWidth = width; }
49
50    unsigned desiredColumnCount() const { return m_desiredColumnCount; }
51    void setDesiredColumnCount(unsigned count) { m_desiredColumnCount = count; }
52
53    unsigned columnCount() const { return m_columnCount; }
54    int columnHeight() const { return m_columnHeight; }
55
56    // Set our count and height.  This is enough info for a RenderBlock to compute page rects
57    // dynamically.
58    void setColumnCountAndHeight(int count, int height)
59    {
60        m_columnCount = count;
61        m_columnHeight = height;
62    }
63    void setColumnHeight(int height) { m_columnHeight = height; }
64
65    void updateMinimumColumnHeight(int height) { m_minimumColumnHeight = std::max(height, m_minimumColumnHeight); }
66    int minimumColumnHeight() const { return m_minimumColumnHeight; }
67
68    int forcedBreaks() const { return m_forcedBreaks; }
69    int forcedBreakOffset() const { return m_forcedBreakOffset; }
70    int maximumDistanceBetweenForcedBreaks() const { return m_maximumDistanceBetweenForcedBreaks; }
71    void clearForcedBreaks()
72    {
73        m_forcedBreaks = 0;
74        m_maximumDistanceBetweenForcedBreaks = 0;
75        m_forcedBreakOffset = 0;
76    }
77    void addForcedBreak(int offsetFromFirstPage)
78    {
79        ASSERT(!m_columnHeight);
80        int distanceFromLastBreak = offsetFromFirstPage - m_forcedBreakOffset;
81        if (!distanceFromLastBreak)
82            return;
83        m_forcedBreaks++;
84        m_maximumDistanceBetweenForcedBreaks = std::max(m_maximumDistanceBetweenForcedBreaks, distanceFromLastBreak);
85        m_forcedBreakOffset = offsetFromFirstPage;
86    }
87
88private:
89    int m_desiredColumnWidth;
90    unsigned m_desiredColumnCount;
91
92    unsigned m_columnCount;
93    int m_columnHeight;
94    int m_minimumColumnHeight;
95    int m_forcedBreaks; // FIXME: We will ultimately need to cache more information to balance around forced breaks properly.
96    int m_maximumDistanceBetweenForcedBreaks;
97    int m_forcedBreakOffset;
98};
99
100}
101
102#endif
103