1/*
2 Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
3
4 This library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Library General Public
6 License as published by the Free Software Foundation; either
7 version 2 of the License, or (at your option) any later version.
8
9 This library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12 Library General Public License for more details.
13
14 You should have received a copy of the GNU Library General Public License
15 along with this library; see the file COPYING.LIB.  If not, write to
16 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 Boston, MA 02110-1301, USA.
18 */
19
20#include "config.h"
21#include "Tile.h"
22
23#if ENABLE(TILED_BACKING_STORE)
24
25#include "GraphicsContext.h"
26#include "TiledBackingStore.h"
27#include "TiledBackingStoreClient.h"
28#include <QApplication>
29#include <QObject>
30#include <QPainter>
31#include <QRegion>
32
33namespace WebCore {
34
35static const unsigned checkerSize = 16;
36static const unsigned checkerColor1 = 0xff555555;
37static const unsigned checkerColor2 = 0xffaaaaaa;
38
39static QPixmap& checkeredPixmap()
40{
41    static QPixmap* pixmap;
42    if (!pixmap) {
43        pixmap = new QPixmap(checkerSize, checkerSize);
44        QPainter painter(pixmap);
45        QColor color1(checkerColor1);
46        QColor color2(checkerColor2);
47        for (unsigned y = 0; y < checkerSize; y += checkerSize / 2) {
48            bool alternate = y % checkerSize;
49            for (unsigned x = 0; x < checkerSize; x += checkerSize / 2) {
50                painter.fillRect(x, y, checkerSize / 2, checkerSize / 2, alternate ? color1 : color2);
51                alternate = !alternate;
52            }
53        }
54    }
55    return *pixmap;
56}
57
58Tile::Tile(TiledBackingStore* backingStore, const Coordinate& tileCoordinate)
59    : m_backingStore(backingStore)
60    , m_coordinate(tileCoordinate)
61    , m_rect(m_backingStore->tileRectForCoordinate(tileCoordinate))
62    , m_buffer(0)
63    , m_backBuffer(0)
64    , m_dirtyRegion(new QRegion(m_rect))
65{
66}
67
68Tile::~Tile()
69{
70    delete m_buffer;
71    delete m_backBuffer;
72    delete m_dirtyRegion;
73}
74
75bool Tile::isDirty() const
76{
77    return !m_dirtyRegion->isEmpty();
78}
79
80bool Tile::isReadyToPaint() const
81{
82    return m_buffer;
83}
84
85void Tile::invalidate(const IntRect& dirtyRect)
86{
87    IntRect tileDirtyRect = intersection(dirtyRect, m_rect);
88    if (tileDirtyRect.isEmpty())
89        return;
90
91    *m_dirtyRegion += tileDirtyRect;
92}
93
94Vector<IntRect> Tile::updateBackBuffer()
95{
96    if (m_buffer && !isDirty())
97        return Vector<IntRect>();
98
99    if (!m_backBuffer) {
100        if (!m_buffer) {
101            m_backBuffer = new QPixmap(m_backingStore->m_tileSize.width(), m_backingStore->m_tileSize.height());
102            m_backBuffer->fill(m_backingStore->m_client->tiledBackingStoreBackgroundColor());
103        } else {
104            // Currently all buffers are updated synchronously at the same time so there is no real need
105            // to have separate back and front buffers. Just use the existing buffer.
106            m_backBuffer = m_buffer;
107            m_buffer = 0;
108        }
109    }
110
111    QVector<QRect> dirtyRects = m_dirtyRegion->rects();
112    *m_dirtyRegion = QRegion();
113
114    QPainter painter(m_backBuffer);
115    GraphicsContext context(&painter);
116    context.translate(-m_rect.x(), -m_rect.y());
117
118    Vector<IntRect> updatedRects;
119    int size = dirtyRects.size();
120    for (int n = 0; n < size; ++n)  {
121        context.save();
122        IntRect rect = dirtyRects[n];
123        updatedRects.append(rect);
124        context.clip(FloatRect(rect));
125        context.scale(FloatSize(m_backingStore->m_contentsScale, m_backingStore->m_contentsScale));
126        m_backingStore->m_client->tiledBackingStorePaint(&context, m_backingStore->mapToContents(rect));
127        context.restore();
128    }
129
130    return updatedRects;
131}
132
133void Tile::swapBackBufferToFront()
134{
135    if (!m_backBuffer)
136        return;
137    delete m_buffer;
138    m_buffer = m_backBuffer;
139    m_backBuffer = 0;
140}
141
142void Tile::paint(GraphicsContext* context, const IntRect& rect)
143{
144    if (!m_buffer)
145        return;
146
147    IntRect target = intersection(rect, m_rect);
148    IntRect source((target.x() - m_rect.x()),
149                   (target.y() - m_rect.y()),
150                   target.width(),
151                   target.height());
152
153    context->platformContext()->drawPixmap(target, *m_buffer, source);
154}
155
156void Tile::paintCheckerPattern(GraphicsContext* context, const FloatRect& target)
157{
158    QPainter* painter = context->platformContext();
159    QTransform worldTransform = painter->worldTransform();
160    qreal scaleX = worldTransform.m11();
161    qreal scaleY = worldTransform.m22();
162
163    QRect targetViewRect = QRectF(target.x() * scaleX,
164                                  target.y() * scaleY,
165                                  target.width() * scaleX,
166                                  target.height() * scaleY).toAlignedRect();
167
168    QTransform adjustedTransform(1., worldTransform.m12(), worldTransform.m13(),
169                  worldTransform.m21(), 1., worldTransform.m23(),
170                  worldTransform.m31(), worldTransform.m32(), worldTransform.m33());
171    painter->setWorldTransform(adjustedTransform);
172
173    painter->drawTiledPixmap(targetViewRect,
174                             checkeredPixmap(),
175                             QPoint(targetViewRect.left() % checkerSize,
176                                    targetViewRect.top() % checkerSize));
177
178    painter->setWorldTransform(worldTransform);
179}
180
181}
182
183#endif
184