1 /*
2 * Copyright (C) 2003, 2004, 2005, 2006, 2010 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 #ifndef Color_h
27 #define Color_h
28
29 #include "platform/animation/AnimationUtilities.h"
30 #include "wtf/FastAllocBase.h"
31 #include "wtf/Forward.h"
32 #include "wtf/unicode/Unicode.h"
33
34 namespace WebCore {
35
36 class Color;
37
38 typedef unsigned RGBA32; // RGBA quadruplet
39
40 PLATFORM_EXPORT RGBA32 makeRGB(int r, int g, int b);
41 PLATFORM_EXPORT RGBA32 makeRGBA(int r, int g, int b, int a);
42
43 PLATFORM_EXPORT RGBA32 colorWithOverrideAlpha(RGBA32 color, float overrideAlpha);
44 PLATFORM_EXPORT RGBA32 makeRGBA32FromFloats(float r, float g, float b, float a);
45 PLATFORM_EXPORT RGBA32 makeRGBAFromHSLA(double h, double s, double l, double a);
46 PLATFORM_EXPORT RGBA32 makeRGBAFromCMYKA(float c, float m, float y, float k, float a);
47
48 PLATFORM_EXPORT int differenceSquared(const Color&, const Color&);
49
redChannel(RGBA32 color)50 inline int redChannel(RGBA32 color) { return (color >> 16) & 0xFF; }
greenChannel(RGBA32 color)51 inline int greenChannel(RGBA32 color) { return (color >> 8) & 0xFF; }
blueChannel(RGBA32 color)52 inline int blueChannel(RGBA32 color) { return color & 0xFF; }
alphaChannel(RGBA32 color)53 inline int alphaChannel(RGBA32 color) { return (color >> 24) & 0xFF; }
54
55 struct NamedColor {
56 const char* name;
57 unsigned ARGBValue;
58 };
59
60 const NamedColor* findColor(register const char* str, register unsigned len);
61
62 class PLATFORM_EXPORT Color {
63 WTF_MAKE_FAST_ALLOCATED;
64 public:
Color()65 Color() : m_color(0), m_valid(false) { }
m_color(color)66 Color(RGBA32 color, bool valid = true) : m_color(color), m_valid(valid) { ASSERT(!m_color || m_valid); }
Color(int r,int g,int b)67 Color(int r, int g, int b) : m_color(makeRGB(r, g, b)), m_valid(true) { }
Color(int r,int g,int b,int a)68 Color(int r, int g, int b, int a) : m_color(makeRGBA(r, g, b, a)), m_valid(true) { }
69 // Color is currently limited to 32bit RGBA, perhaps some day we'll support better colors
Color(float r,float g,float b,float a)70 Color(float r, float g, float b, float a) : m_color(makeRGBA32FromFloats(r, g, b, a)), m_valid(true) { }
71 // Creates a new color from the specific CMYK and alpha values.
Color(float c,float m,float y,float k,float a)72 Color(float c, float m, float y, float k, float a) : m_color(makeRGBAFromCMYKA(c, m, y, k, a)), m_valid(true) { }
73 explicit Color(const String&);
74 explicit Color(const char*);
75
createUnchecked(int r,int g,int b)76 static Color createUnchecked(int r, int g, int b)
77 {
78 RGBA32 color = 0xFF000000 | r << 16 | g << 8 | b;
79 return Color(color);
80 }
createUnchecked(int r,int g,int b,int a)81 static Color createUnchecked(int r, int g, int b, int a)
82 {
83 RGBA32 color = a << 24 | r << 16 | g << 8 | b;
84 return Color(color);
85 }
86
87 // Returns the color serialized according to HTML5
88 // - http://www.whatwg.org/specs/web-apps/current-work/#serialization-of-a-color
89 String serialized() const;
90
91 // Returns the color serialized as either #RRGGBB or #RRGGBBAA
92 // The latter format is not a valid CSS color, and should only be seen in DRT dumps.
93 String nameForRenderTreeAsText() const;
94
95 void setNamedColor(const String&);
96
isValid()97 bool isValid() const { return m_valid; }
98
hasAlpha()99 bool hasAlpha() const { return alpha() < 255; }
100
red()101 int red() const { return redChannel(m_color); }
green()102 int green() const { return greenChannel(m_color); }
blue()103 int blue() const { return blueChannel(m_color); }
alpha()104 int alpha() const { return alphaChannel(m_color); }
105
rgb()106 RGBA32 rgb() const { return m_color; } // Preserve the alpha.
setRGB(int r,int g,int b)107 void setRGB(int r, int g, int b) { m_color = makeRGB(r, g, b); m_valid = true; }
setRGB(RGBA32 rgb)108 void setRGB(RGBA32 rgb) { m_color = rgb; m_valid = true; }
109 void getRGBA(float& r, float& g, float& b, float& a) const;
110 void getRGBA(double& r, double& g, double& b, double& a) const;
111 void getHSL(double& h, double& s, double& l) const;
112
113 Color light() const;
114 Color dark() const;
115
116 // This is an implementation of Porter-Duff's "source-over" equation
117 Color blend(const Color&) const;
118 Color blendWithWhite() const;
119
120 static bool parseHexColor(const String&, RGBA32&);
121 static bool parseHexColor(const LChar*, unsigned, RGBA32&);
122 static bool parseHexColor(const UChar*, unsigned, RGBA32&);
123
124 static const RGBA32 black = 0xFF000000;
125 static const RGBA32 white = 0xFFFFFFFF;
126 static const RGBA32 darkGray = 0xFF808080;
127 static const RGBA32 gray = 0xFFA0A0A0;
128 static const RGBA32 lightGray = 0xFFC0C0C0;
129 static const RGBA32 transparent = 0x00000000;
130
131 private:
132 RGBA32 m_color;
133 bool m_valid;
134 };
135
136 inline bool operator==(const Color& a, const Color& b)
137 {
138 return a.rgb() == b.rgb() && a.isValid() == b.isValid();
139 }
140
141 inline bool operator!=(const Color& a, const Color& b)
142 {
143 return !(a == b);
144 }
145
146 PLATFORM_EXPORT Color colorFromPremultipliedARGB(RGBA32);
147 PLATFORM_EXPORT RGBA32 premultipliedARGBFromColor(const Color&);
148
149 inline Color blend(const Color& from, const Color& to, double progress, bool blendPremultiplied = true)
150 {
151 // We need to preserve the state of the valid flag at the end of the animation
152 if (progress == 1 && !to.isValid())
153 return Color();
154
155 if (blendPremultiplied) {
156 // Contrary to the name, RGBA32 actually stores ARGB, so we can initialize Color directly from premultipliedARGBFromColor().
157 // Also, premultipliedARGBFromColor() bails on zero alpha, so special-case that.
158 Color premultFrom = from.alpha() ? premultipliedARGBFromColor(from) : 0;
159 Color premultTo = to.alpha() ? premultipliedARGBFromColor(to) : 0;
160
161 Color premultBlended(blend(premultFrom.red(), premultTo.red(), progress),
162 blend(premultFrom.green(), premultTo.green(), progress),
163 blend(premultFrom.blue(), premultTo.blue(), progress),
164 blend(premultFrom.alpha(), premultTo.alpha(), progress));
165
166 return Color(colorFromPremultipliedARGB(premultBlended.rgb()));
167 }
168
169 return Color(blend(from.red(), to.red(), progress),
170 blend(from.green(), to.green(), progress),
171 blend(from.blue(), to.blue(), progress),
172 blend(from.alpha(), to.alpha(), progress));
173 }
174 } // namespace WebCore
175
176 #endif // Color_h
177