1/*
2 * Copyright (C) 2006, 2008 Apple Inc. All rights reserved.
3 * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
18 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
19 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
20 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
21 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
22 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#ifndef CanvasStyle_h
28#define CanvasStyle_h
29
30#include "platform/graphics/Color.h"
31#include "platform/heap/Handle.h"
32#include "wtf/Assertions.h"
33#include "wtf/RefCounted.h"
34#include "wtf/text/WTFString.h"
35
36namespace blink {
37
38    class CanvasGradient;
39    class CanvasPattern;
40    class GraphicsContext;
41    class HTMLCanvasElement;
42
43    class CanvasStyle FINAL : public RefCountedWillBeGarbageCollected<CanvasStyle> {
44    public:
45        static PassRefPtrWillBeRawPtr<CanvasStyle> createFromRGBA(RGBA32 rgba) { return adoptRefWillBeNoop(new CanvasStyle(rgba)); }
46        static PassRefPtrWillBeRawPtr<CanvasStyle> createFromString(const String& color);
47        static PassRefPtrWillBeRawPtr<CanvasStyle> createFromStringWithOverrideAlpha(const String& color, float alpha);
48        static PassRefPtrWillBeRawPtr<CanvasStyle> createFromGrayLevelWithAlpha(float grayLevel, float alpha) { return adoptRefWillBeNoop(new CanvasStyle(grayLevel, alpha)); }
49        static PassRefPtrWillBeRawPtr<CanvasStyle> createFromRGBAChannels(float r, float g, float b, float a) { return adoptRefWillBeNoop(new CanvasStyle(r, g, b, a)); }
50        static PassRefPtrWillBeRawPtr<CanvasStyle> createFromCMYKAChannels(float c, float m, float y, float k, float a) { return adoptRefWillBeNoop(new CanvasStyle(c, m, y, k, a)); }
51        static PassRefPtrWillBeRawPtr<CanvasStyle> createFromGradient(PassRefPtrWillBeRawPtr<CanvasGradient>);
52        static PassRefPtrWillBeRawPtr<CanvasStyle> createFromPattern(PassRefPtrWillBeRawPtr<CanvasPattern>);
53
54        bool isCurrentColor() const { return m_type == CurrentColor || m_type == CurrentColorWithOverrideAlpha; }
55        bool hasOverrideAlpha() const { return m_type == CurrentColorWithOverrideAlpha; }
56        float overrideAlpha() const { ASSERT(m_type == CurrentColorWithOverrideAlpha); return m_overrideAlpha; }
57
58        String color() const { ASSERT(m_type == RGBA || m_type == CMYKA); return Color(m_rgba).serialized(); }
59        CanvasGradient* canvasGradient() const { return m_gradient.get(); }
60        CanvasPattern* canvasPattern() const { return m_pattern.get(); }
61
62        void applyFillColor(GraphicsContext*);
63        void applyStrokeColor(GraphicsContext*);
64
65        bool isEquivalentColor(const CanvasStyle&) const;
66        bool isEquivalentRGBA(float r, float g, float b, float a) const;
67        bool isEquivalentCMYKA(float c, float m, float y, float k, float a) const;
68
69        void trace(Visitor*);
70
71    private:
72        enum Type { RGBA, CMYKA, Gradient, ImagePattern, CurrentColor, CurrentColorWithOverrideAlpha };
73
74        CanvasStyle(Type, float overrideAlpha = 0);
75        CanvasStyle(RGBA32 rgba);
76        CanvasStyle(float grayLevel, float alpha);
77        CanvasStyle(float r, float g, float b, float a);
78        CanvasStyle(float c, float m, float y, float k, float a);
79        CanvasStyle(PassRefPtrWillBeRawPtr<CanvasGradient>);
80        CanvasStyle(PassRefPtrWillBeRawPtr<CanvasPattern>);
81
82        Type m_type;
83
84        union {
85            RGBA32 m_rgba;
86            float m_overrideAlpha;
87        };
88
89        RefPtrWillBeMember<CanvasGradient> m_gradient;
90        RefPtrWillBeMember<CanvasPattern> m_pattern;
91
92        struct CMYKAValues {
93            CMYKAValues() : c(0), m(0), y(0), k(0), a(0) { }
94            CMYKAValues(float cyan, float magenta, float yellow, float black, float alpha) : c(cyan), m(magenta), y(yellow), k(black), a(alpha) { }
95            float c;
96            float m;
97            float y;
98            float k;
99            float a;
100        } m_cmyka;
101    };
102
103    RGBA32 currentColor(HTMLCanvasElement*);
104    bool parseColorOrCurrentColor(RGBA32& parsedColor, const String& colorString, HTMLCanvasElement*);
105
106} // namespace blink
107
108#endif
109