1 /*
2 * Copyright (C) 2018 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
17 #include "CanvasTransform.h"
18 #include "Properties.h"
19 #include "utils/Color.h"
20
21 #include <SkColorFilter.h>
22 #include <SkGradientShader.h>
23 #include <SkPaint.h>
24 #include <SkShader.h>
25 #include <ui/ColorSpace.h>
26
27 #include <algorithm>
28 #include <cmath>
29
30 #include <log/log.h>
31 #include <SkHighContrastFilter.h>
32
33 namespace android::uirenderer {
34
makeLight(SkColor color)35 static SkColor makeLight(SkColor color) {
36 Lab lab = sRGBToLab(color);
37 float invertedL = std::min(110 - lab.L, 100.0f);
38 if (invertedL > lab.L) {
39 lab.L = invertedL;
40 return LabToSRGB(lab, SkColorGetA(color));
41 } else {
42 return color;
43 }
44 }
45
makeDark(SkColor color)46 static SkColor makeDark(SkColor color) {
47 Lab lab = sRGBToLab(color);
48 float invertedL = std::min(110 - lab.L, 100.0f);
49 if (invertedL < lab.L) {
50 lab.L = invertedL;
51 return LabToSRGB(lab, SkColorGetA(color));
52 } else {
53 return color;
54 }
55 }
56
transformColor(ColorTransform transform,SkColor color)57 static SkColor transformColor(ColorTransform transform, SkColor color) {
58 switch (transform) {
59 case ColorTransform::Light:
60 return makeLight(color);
61 case ColorTransform::Dark:
62 return makeDark(color);
63 default:
64 return color;
65 }
66 }
67
applyColorTransform(ColorTransform transform,SkPaint & paint)68 static void applyColorTransform(ColorTransform transform, SkPaint& paint) {
69 if (transform == ColorTransform::None) return;
70
71 SkColor newColor = transformColor(transform, paint.getColor());
72 paint.setColor(newColor);
73
74 if (paint.getShader()) {
75 SkShader::GradientInfo info;
76 std::array<SkColor, 10> _colorStorage;
77 std::array<SkScalar, _colorStorage.size()> _offsetStorage;
78 info.fColorCount = _colorStorage.size();
79 info.fColors = _colorStorage.data();
80 info.fColorOffsets = _offsetStorage.data();
81 SkShader::GradientType type = paint.getShader()->asAGradient(&info);
82
83 if (info.fColorCount <= 10) {
84 switch (type) {
85 case SkShader::kLinear_GradientType:
86 for (int i = 0; i < info.fColorCount; i++) {
87 info.fColors[i] = transformColor(transform, info.fColors[i]);
88 }
89 paint.setShader(SkGradientShader::MakeLinear(info.fPoint, info.fColors,
90 info.fColorOffsets, info.fColorCount,
91 info.fTileMode, info.fGradientFlags, nullptr));
92 break;
93 default:break;
94 }
95
96 }
97 }
98
99 if (paint.getColorFilter()) {
100 SkBlendMode mode;
101 SkColor color;
102 // TODO: LRU this or something to avoid spamming new color mode filters
103 if (paint.getColorFilter()->asAColorMode(&color, &mode)) {
104 color = transformColor(transform, color);
105 paint.setColorFilter(SkColorFilters::Blend(color, mode));
106 }
107 }
108 }
109
paletteForColorHSV(SkColor color)110 static BitmapPalette paletteForColorHSV(SkColor color) {
111 float hsv[3];
112 SkColorToHSV(color, hsv);
113 return hsv[2] >= .5f ? BitmapPalette::Light : BitmapPalette::Dark;
114 }
115
filterPalette(const SkPaint * paint,BitmapPalette palette)116 static BitmapPalette filterPalette(const SkPaint* paint, BitmapPalette palette) {
117 if (palette == BitmapPalette::Unknown || !paint || !paint->getColorFilter()) {
118 return palette;
119 }
120
121 SkColor color = palette == BitmapPalette::Light ? SK_ColorWHITE : SK_ColorBLACK;
122 color = paint->getColorFilter()->filterColor(color);
123 return paletteForColorHSV(color);
124 }
125
transformPaint(ColorTransform transform,SkPaint * paint)126 bool transformPaint(ColorTransform transform, SkPaint* paint) {
127 // TODO
128 applyColorTransform(transform, *paint);
129 return true;
130 }
131
transformPaint(ColorTransform transform,SkPaint * paint,BitmapPalette palette)132 bool transformPaint(ColorTransform transform, SkPaint* paint, BitmapPalette palette) {
133 palette = filterPalette(paint, palette);
134 bool shouldInvert = false;
135 if (palette == BitmapPalette::Light && transform == ColorTransform::Dark) {
136 shouldInvert = true;
137 }
138 if (palette == BitmapPalette::Dark && transform == ColorTransform::Light) {
139 shouldInvert = true;
140 }
141 if (shouldInvert) {
142 SkHighContrastConfig config;
143 config.fInvertStyle = SkHighContrastConfig::InvertStyle::kInvertLightness;
144 paint->setColorFilter(SkHighContrastFilter::Make(config)->makeComposed(paint->refColorFilter()));
145 }
146 return shouldInvert;
147 }
148
149 } // namespace android::uirenderer
150