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 "Color.h"
31 #include "PlatformString.h"
32 #include <wtf/Assertions.h>
33 
34 namespace WebCore {
35 
36     class CanvasGradient;
37     class CanvasPattern;
38     class Document;
39     class GraphicsContext;
40     class HTMLCanvasElement;
41 
42     class CanvasStyle : public RefCounted<CanvasStyle> {
43     public:
createFromRGBA(RGBA32 rgba)44         static PassRefPtr<CanvasStyle> createFromRGBA(RGBA32 rgba) { return adoptRef(new CanvasStyle(rgba)); }
45         static PassRefPtr<CanvasStyle> createFromString(const String& color, Document* = 0);
46         static PassRefPtr<CanvasStyle> createFromStringWithOverrideAlpha(const String& color, float alpha);
createFromGrayLevelWithAlpha(float grayLevel,float alpha)47         static PassRefPtr<CanvasStyle> createFromGrayLevelWithAlpha(float grayLevel, float alpha) { return adoptRef(new CanvasStyle(grayLevel, alpha)); }
createFromRGBAChannels(float r,float g,float b,float a)48         static PassRefPtr<CanvasStyle> createFromRGBAChannels(float r, float g, float b, float a) { return adoptRef(new CanvasStyle(r, g, b, a)); }
createFromCMYKAChannels(float c,float m,float y,float k,float a)49         static PassRefPtr<CanvasStyle> createFromCMYKAChannels(float c, float m, float y, float k, float a) { return adoptRef(new CanvasStyle(c, m, y, k, a)); }
50         static PassRefPtr<CanvasStyle> createFromGradient(PassRefPtr<CanvasGradient>);
51         static PassRefPtr<CanvasStyle> createFromPattern(PassRefPtr<CanvasPattern>);
52 
isCurrentColor()53         bool isCurrentColor() const { return m_type == CurrentColor || m_type == CurrentColorWithOverrideAlpha; }
hasOverrideAlpha()54         bool hasOverrideAlpha() const { return m_type == CurrentColorWithOverrideAlpha; }
overrideAlpha()55         float overrideAlpha() const { ASSERT(m_type == CurrentColorWithOverrideAlpha); return m_overrideAlpha; }
56 
color()57         String color() const { ASSERT(m_type == RGBA || m_type == CMYKA); return Color(m_rgba).serialized(); }
canvasGradient()58         CanvasGradient* canvasGradient() const { return m_gradient.get(); }
canvasPattern()59         CanvasPattern* canvasPattern() const { return m_pattern.get(); }
60 
61         void applyFillColor(GraphicsContext*);
62         void applyStrokeColor(GraphicsContext*);
63 
64         bool isEquivalentColor(const CanvasStyle&) const;
65         bool isEquivalentRGBA(float r, float g, float b, float a) const;
66         bool isEquivalentCMYKA(float c, float m, float y, float k, float a) const;
67 
68     private:
69         enum Type { RGBA, CMYKA, Gradient, ImagePattern, CurrentColor, CurrentColorWithOverrideAlpha };
70 
71         CanvasStyle(Type, float overrideAlpha = 0);
72         CanvasStyle(RGBA32 rgba);
73         CanvasStyle(float grayLevel, float alpha);
74         CanvasStyle(float r, float g, float b, float a);
75         CanvasStyle(float c, float m, float y, float k, float a);
76         CanvasStyle(PassRefPtr<CanvasGradient>);
77         CanvasStyle(PassRefPtr<CanvasPattern>);
78 
79         Type m_type;
80 
81         union {
82             RGBA32 m_rgba;
83             float m_overrideAlpha;
84         };
85 
86         RefPtr<CanvasGradient> m_gradient;
87         RefPtr<CanvasPattern> m_pattern;
88 
89         struct CMYKAValues {
CMYKAValuesCMYKAValues90             CMYKAValues() {}
CMYKAValuesCMYKAValues91             CMYKAValues(float cyan, float magenta, float yellow, float black, float alpha) : c(cyan), m(magenta), y(yellow), k(black), a(alpha) {}
92             float c;
93             float m;
94             float y;
95             float k;
96             float a;
97         } m_cmyka;
98     };
99 
100     RGBA32 currentColor(HTMLCanvasElement*);
101     bool parseColorOrCurrentColor(RGBA32& parsedColor, const String& colorString, HTMLCanvasElement*);
102 
103 } // namespace WebCore
104 
105 #endif
106