1/*
2 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 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 COMPUTER, 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 COMPUTER, 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#include "config.h"
27#include "GraphicsContext.h"
28
29#if USE(CG)
30#include "GraphicsContextPlatformPrivateCG.h"
31#elif USE(CAIRO)
32#include "GraphicsContextPlatformPrivateCairo.h"
33#endif
34
35#include "AffineTransform.h"
36#include "BitmapInfo.h"
37#include "TransformationMatrix.h"
38#include "NotImplemented.h"
39#include "Path.h"
40#include <wtf/MathExtras.h>
41
42using namespace std;
43
44namespace WebCore {
45
46static void fillWithClearColor(HBITMAP bitmap)
47{
48    BITMAP bmpInfo;
49    GetObject(bitmap, sizeof(bmpInfo), &bmpInfo);
50    int bufferSize = bmpInfo.bmWidthBytes * bmpInfo.bmHeight;
51    memset(bmpInfo.bmBits, 0, bufferSize);
52}
53
54#if PLATFORM(WIN)
55void GraphicsContext::setShouldIncludeChildWindows(bool include)
56{
57    m_data->m_shouldIncludeChildWindows = include;
58}
59
60bool GraphicsContext::shouldIncludeChildWindows() const
61{
62    return m_data->m_shouldIncludeChildWindows;
63}
64
65GraphicsContext::WindowsBitmap::WindowsBitmap(HDC hdc, const IntSize& size)
66    : m_hdc(0)
67{
68    BitmapInfo bitmapInfo = BitmapInfo::create(size);
69
70    void* storage = 0;
71    m_bitmap = CreateDIBSection(0, &bitmapInfo, DIB_RGB_COLORS, &storage, 0, 0);
72    if (!m_bitmap)
73        return;
74
75    m_hdc = CreateCompatibleDC(hdc);
76    SelectObject(m_hdc, m_bitmap);
77
78    m_pixelData.initialize(m_bitmap);
79
80    ASSERT(storage == m_pixelData.buffer());
81
82    SetGraphicsMode(m_hdc, GM_ADVANCED);
83}
84
85GraphicsContext::WindowsBitmap::~WindowsBitmap()
86{
87    if (!m_bitmap)
88        return;
89
90    DeleteDC(m_hdc);
91    DeleteObject(m_bitmap);
92}
93
94PassOwnPtr<GraphicsContext::WindowsBitmap> GraphicsContext::createWindowsBitmap(const IntSize& size)
95{
96    return adoptPtr(new WindowsBitmap(m_data->m_hdc, size));
97}
98#endif
99
100HDC GraphicsContext::getWindowsContext(const IntRect& dstRect, bool supportAlphaBlend, bool mayCreateBitmap)
101{
102    // FIXME: Should a bitmap be created also when a shadow is set?
103    if (mayCreateBitmap && (!m_data->m_hdc || isInTransparencyLayer())) {
104        if (dstRect.isEmpty())
105            return 0;
106
107        // Create a bitmap DC in which to draw.
108        BitmapInfo bitmapInfo = BitmapInfo::create(dstRect.size());
109
110        void* pixels = 0;
111        HBITMAP bitmap = ::CreateDIBSection(NULL, &bitmapInfo, DIB_RGB_COLORS, &pixels, 0, 0);
112        if (!bitmap)
113            return 0;
114
115        HDC bitmapDC = ::CreateCompatibleDC(m_data->m_hdc);
116        ::SelectObject(bitmapDC, bitmap);
117
118        // Fill our buffer with clear if we're going to alpha blend.
119        if (supportAlphaBlend)
120           fillWithClearColor(bitmap);
121
122        // Make sure we can do world transforms.
123        SetGraphicsMode(bitmapDC, GM_ADVANCED);
124
125        // Apply a translation to our context so that the drawing done will be at (0,0) of the bitmap.
126        XFORM xform = TransformationMatrix().translate(-dstRect.x(), -dstRect.y());
127
128        ::SetWorldTransform(bitmapDC, &xform);
129
130        return bitmapDC;
131    }
132
133    m_data->flush();
134    m_data->save();
135    return m_data->m_hdc;
136}
137
138#if PLATFORM(WIN)
139void GraphicsContextPlatformPrivate::save()
140{
141    if (!m_hdc)
142        return;
143    SaveDC(m_hdc);
144}
145
146void GraphicsContextPlatformPrivate::restore()
147{
148    if (!m_hdc)
149        return;
150    RestoreDC(m_hdc, -1);
151}
152
153void GraphicsContextPlatformPrivate::clip(const FloatRect& clipRect)
154{
155    if (!m_hdc)
156        return;
157    IntersectClipRect(m_hdc, clipRect.x(), clipRect.y(), clipRect.maxX(), clipRect.maxY());
158}
159
160void GraphicsContextPlatformPrivate::clip(const Path&)
161{
162    notImplemented();
163}
164
165void GraphicsContextPlatformPrivate::scale(const FloatSize& size)
166{
167    if (!m_hdc)
168        return;
169
170    XFORM xform = TransformationMatrix().scaleNonUniform(size.width(), size.height());
171    ModifyWorldTransform(m_hdc, &xform, MWT_LEFTMULTIPLY);
172}
173
174static const double deg2rad = 0.017453292519943295769; // pi/180
175
176void GraphicsContextPlatformPrivate::rotate(float degreesAngle)
177{
178    XFORM xform = TransformationMatrix().rotate(degreesAngle);
179    ModifyWorldTransform(m_hdc, &xform, MWT_LEFTMULTIPLY);
180}
181
182void GraphicsContextPlatformPrivate::translate(float x , float y)
183{
184    if (!m_hdc)
185        return;
186
187    XFORM xform = TransformationMatrix().translate(x, y);
188    ModifyWorldTransform(m_hdc, &xform, MWT_LEFTMULTIPLY);
189}
190
191void GraphicsContextPlatformPrivate::concatCTM(const AffineTransform& transform)
192{
193    if (!m_hdc)
194        return;
195
196    XFORM xform = transform.toTransformationMatrix();
197    ModifyWorldTransform(m_hdc, &xform, MWT_LEFTMULTIPLY);
198}
199
200void GraphicsContextPlatformPrivate::setCTM(const AffineTransform& transform)
201{
202    if (!m_hdc)
203        return;
204
205    XFORM xform = transform.toTransformationMatrix();
206    SetWorldTransform(m_hdc, &xform);
207}
208#endif
209
210}
211