1/**
2 * Copyright (C) 2007 Rob Buis <buis@kde.org>
3 * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
4 * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
5 * Copyright (C) 2009 Google, Inc.  All rights reserved.
6 * Copyright (C) Research In Motion Limited 2010. All rights reserved.
7 * Copyright (C) 2012 Zoltan Herczeg <zherczeg@webkit.org>.
8 *
9 * This library is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Library General Public
11 * License as published by the Free Software Foundation; either
12 * version 2 of the License, or (at your option) any later version.
13 *
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 * Library General Public License for more details.
18 *
19 * You should have received a copy of the GNU Library General Public License
20 * along with this library; see the file COPYING.LIB.  If not, write to
21 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
22 * Boston, MA 02110-1301, USA.
23 */
24
25#ifndef SVGRenderingContext_h
26#define SVGRenderingContext_h
27
28#include "core/rendering/PaintInfo.h"
29#include "core/rendering/svg/RenderSVGResourceClipper.h"
30#include "platform/graphics/ImageBuffer.h"
31
32namespace blink {
33
34class AffineTransform;
35class RenderObject;
36class FloatRect;
37class RenderSVGResourceFilter;
38class RenderSVGResourceMasker;
39
40// SVGRenderingContext
41class SVGRenderingContext {
42public:
43    // Does not start rendering.
44    SVGRenderingContext()
45        : m_renderingFlags(0)
46        , m_object(0)
47        , m_paintInfo(0)
48        , m_savedContext(0)
49        , m_filter(0)
50        , m_clipper(0)
51        , m_clipperState(RenderSVGResourceClipper::ClipperNotApplied)
52        , m_masker(0)
53    {
54    }
55
56    SVGRenderingContext(RenderObject* object, PaintInfo& paintinfo)
57        : m_renderingFlags(0)
58        , m_object(0)
59        , m_paintInfo(0)
60        , m_savedContext(0)
61        , m_filter(0)
62        , m_clipper(0)
63        , m_clipperState(RenderSVGResourceClipper::ClipperNotApplied)
64        , m_masker(0)
65    {
66        prepareToRenderSVGContent(object, paintinfo);
67    }
68
69    // Automatically finishes context rendering.
70    ~SVGRenderingContext();
71
72    // Used by all SVG renderers who apply clip/filter/etc. resources to the renderer content.
73    void prepareToRenderSVGContent(RenderObject*, PaintInfo&);
74    bool isRenderingPrepared() const { return m_renderingFlags & RenderingPrepared; }
75
76    static void renderSubtree(GraphicsContext*, RenderObject*, const AffineTransform&);
77
78    static float calculateScreenFontSizeScalingFactor(const RenderObject*);
79    static void calculateDeviceSpaceTransformation(const RenderObject*, AffineTransform& absoluteTransform);
80    static FloatRect clampedAbsoluteTargetRect(const FloatRect& absoluteTargetRect);
81    static void clear2DRotation(AffineTransform&);
82
83    static IntRect calculateImageBufferRect(const FloatRect& targetRect, const AffineTransform& absoluteTransform)
84    {
85        return enclosingIntRect(absoluteTransform.mapRect(targetRect));
86    }
87
88    // Support for the buffered-rendering hint.
89    bool bufferForeground(OwnPtr<ImageBuffer>&);
90
91private:
92    // To properly revert partially successful initializtions in the destructor, we record all successful steps.
93    enum RenderingFlags {
94        RenderingPrepared = 1,
95        RestoreGraphicsContext = 1 << 1,
96        EndOpacityLayer = 1 << 2,
97        PostApplyResources = 1 << 3,
98        PrepareToRenderSVGContentWasCalled = 1 << 4
99    };
100
101    // List of those flags which require actions during the destructor.
102    const static int ActionsNeeded = RestoreGraphicsContext | EndOpacityLayer | PostApplyResources;
103
104    int m_renderingFlags;
105    RenderObject* m_object;
106    PaintInfo* m_paintInfo;
107    GraphicsContext* m_savedContext;
108    IntRect m_savedPaintRect;
109    RenderSVGResourceFilter* m_filter;
110    RenderSVGResourceClipper* m_clipper;
111    RenderSVGResourceClipper::ClipperState m_clipperState;
112    RenderSVGResourceMasker* m_masker;
113};
114
115} // namespace blink
116
117#endif // SVGRenderingContext_h
118