Color.h revision caaaa66e57293e4a6f312649bf472eab84d5c7fe
1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16#ifndef COLOR_H
17#define COLOR_H
18
19#include <math.h>
20
21#include <SkColor.h>
22#include <SkColorSpace.h>
23
24namespace android {
25namespace uirenderer {
26    namespace Color {
27        enum Color {
28            Red_500 = 0xFFF44336,
29            Pink_500 = 0xFFE91E63,
30            Purple_500 = 0xFF9C27B0,
31            DeepPurple_500 = 0xFF673AB7,
32            Indigo_500 = 0xFF3F51B5,
33            Blue_500 = 0xFF2196F3,
34            LightBlue_300 = 0xFF4FC3F7,
35            LightBlue_500 = 0xFF03A9F4,
36            Cyan_500 = 0xFF00BCD4,
37            Teal_500 = 0xFF009688,
38            Teal_700 = 0xFF00796B,
39            Green_500 = 0xFF4CAF50,
40            Green_700 = 0xFF388E3C,
41            LightGreen_500 = 0xFF8BC34A,
42            LightGreen_700 = 0xFF689F38,
43            Lime_500 = 0xFFCDDC39,
44            Yellow_500 = 0xFFFFEB3B,
45            Amber_500 = 0xFFFFC107,
46            Orange_500 = 0xFFFF9800,
47            DeepOrange_500 = 0xFFFF5722,
48            Brown_500 = 0xFF795548,
49            Grey_200 = 0xFFEEEEEE,
50            Grey_500 = 0xFF9E9E9E,
51            Grey_700 = 0xFF616161,
52            BlueGrey_500 = 0xFF607D8B,
53            Transparent = 0x00000000,
54            Black = 0xFF000000,
55            White = 0xFFFFFFFF,
56        };
57    }
58
59    static_assert(Color::White == SK_ColorWHITE, "color format has changed");
60    static_assert(Color::Black == SK_ColorBLACK, "color format has changed");
61
62    // Array of bright (500 intensity) colors for synthetic content
63    static const Color::Color BrightColors[] = {
64        Color::Red_500,
65        Color::Pink_500,
66        Color::Purple_500,
67        Color::DeepPurple_500,
68        Color::Indigo_500,
69        Color::Blue_500,
70        Color::LightBlue_500,
71        Color::Cyan_500,
72        Color::Teal_500,
73        Color::Green_500,
74        Color::LightGreen_500,
75        Color::Lime_500,
76        Color::Yellow_500,
77        Color::Amber_500,
78        Color::Orange_500,
79        Color::DeepOrange_500,
80        Color::Brown_500,
81        Color::Grey_500,
82        Color::BlueGrey_500,
83    };
84    static constexpr int BrightColorsCount = sizeof(BrightColors) / sizeof(Color::Color);
85
86    enum class TransferFunctionType : int8_t {
87        None = 0,
88        Full,
89        Limited,
90        Gamma
91    };
92
93    // Opto-electronic conversion function for the sRGB color space
94    // Takes a linear sRGB value and converts it to a gamma-encoded sRGB value
95    static constexpr float OECF_sRGB(float linear) {
96        // IEC 61966-2-1:1999
97        return linear <= 0.0031308f ?
98                linear * 12.92f : (powf(linear, 1.0f / 2.4f) * 1.055f) - 0.055f;
99    }
100
101    // Opto-electronic conversion function for the sRGB color space
102    // Takes a linear sRGB value and converts it to a gamma-encoded sRGB value
103    // This function returns the input unmodified if linear blending is not enabled
104    static constexpr float OECF(float linear) {
105#ifdef ANDROID_ENABLE_LINEAR_BLENDING
106        return OECF_sRGB(linear);
107#else
108        return linear;
109#endif
110    }
111
112    // Electro-optical conversion function for the sRGB color space
113    // Takes a gamma-encoded sRGB value and converts it to a linear sRGB value
114    static constexpr float EOCF_sRGB(float srgb) {
115        // IEC 61966-2-1:1999
116        return srgb <= 0.04045f ? srgb / 12.92f : powf((srgb + 0.055f) / 1.055f, 2.4f);
117    }
118
119    // Electro-optical conversion function for the sRGB color space
120    // Takes a gamma-encoded sRGB value and converts it to a linear sRGB value
121    // This function returns the input unmodified if linear blending is not enabled
122    static constexpr float EOCF(float srgb) {
123#ifdef ANDROID_ENABLE_LINEAR_BLENDING
124        return EOCF_sRGB(srgb);
125#else
126        return srgb;
127#endif
128    }
129
130    // Returns whether the specified color space's transfer function can be
131    // approximated with the native sRGB transfer function. This method
132    // returns true for sRGB, gamma 2.2 and Display P3 for instance
133    bool transferFunctionCloseToSRGB(const SkColorSpace* colorSpace);
134} /* namespace uirenderer */
135} /* namespace android */
136
137#endif /* COLOR_H */
138