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
19 #include <SkAndroidFrameworkUtils.h>
20 #include <SkBlendMode.h>
21 #include <SkColorFilter.h>
22 #include <SkGradientShader.h>
23 #include <SkHighContrastFilter.h>
24 #include <SkPaint.h>
25 #include <SkShader.h>
26 #include <log/log.h>
27
28 #include <algorithm>
29 #include <cmath>
30
31 #include "Properties.h"
32 #include "utils/Color.h"
33
34 namespace android::uirenderer {
35
makeLight(SkColor color)36 SkColor makeLight(SkColor color) {
37 Lab lab = sRGBToLab(color);
38 float invertedL = std::min(110 - lab.L, 100.0f);
39 if (invertedL > lab.L) {
40 lab.L = invertedL;
41 return LabToSRGB(lab, SkColorGetA(color));
42 } else {
43 return color;
44 }
45 }
46
makeDark(SkColor color)47 SkColor makeDark(SkColor color) {
48 Lab lab = sRGBToLab(color);
49 float invertedL = std::min(110 - lab.L, 100.0f);
50 if (invertedL < lab.L) {
51 lab.L = invertedL;
52 return LabToSRGB(lab, SkColorGetA(color));
53 } else {
54 return color;
55 }
56 }
57
transformColor(ColorTransform transform,SkColor color)58 SkColor transformColor(ColorTransform transform, SkColor color) {
59 switch (transform) {
60 case ColorTransform::Light:
61 return makeLight(color);
62 case ColorTransform::Dark:
63 return makeDark(color);
64 default:
65 return color;
66 }
67 }
68
transformColorInverse(ColorTransform transform,SkColor color)69 SkColor transformColorInverse(ColorTransform transform, SkColor color) {
70 switch (transform) {
71 case ColorTransform::Dark:
72 return makeLight(color);
73 case ColorTransform::Light:
74 return makeDark(color);
75 default:
76 return color;
77 }
78 }
79
applyColorTransform(ColorTransform transform,SkPaint & paint)80 static void applyColorTransform(ColorTransform transform, SkPaint& paint) {
81 if (transform == ColorTransform::None) return;
82
83 if (transform == ColorTransform::Invert) {
84 auto filter = SkHighContrastFilter::Make(
85 {/* grayscale= */ false, SkHighContrastConfig::InvertStyle::kInvertLightness,
86 /* contrast= */ 0.0f});
87
88 if (paint.getColorFilter()) {
89 paint.setColorFilter(SkColorFilters::Compose(filter, paint.refColorFilter()));
90 } else {
91 paint.setColorFilter(filter);
92 }
93 return;
94 }
95
96 SkColor newColor = transformColor(transform, paint.getColor());
97 paint.setColor(newColor);
98
99 if (paint.getShader()) {
100 SkAndroidFrameworkUtils::LinearGradientInfo info;
101 std::array<SkColor, 10> _colorStorage;
102 std::array<SkScalar, _colorStorage.size()> _offsetStorage;
103 info.fColorCount = _colorStorage.size();
104 info.fColors = _colorStorage.data();
105 info.fColorOffsets = _offsetStorage.data();
106
107 if (SkAndroidFrameworkUtils::ShaderAsALinearGradient(paint.getShader(), &info) &&
108 info.fColorCount <= _colorStorage.size()) {
109 for (int i = 0; i < info.fColorCount; i++) {
110 info.fColors[i] = transformColor(transform, info.fColors[i]);
111 }
112 paint.setShader(SkGradientShader::MakeLinear(
113 info.fPoints, info.fColors, info.fColorOffsets, info.fColorCount,
114 info.fTileMode, info.fGradientFlags, nullptr));
115 }
116 }
117
118 if (paint.getColorFilter()) {
119 SkBlendMode mode;
120 SkColor color;
121 // TODO: LRU this or something to avoid spamming new color mode filters
122 if (paint.getColorFilter()->asAColorMode(&color, &mode)) {
123 color = transformColor(transform, color);
124 paint.setColorFilter(SkColorFilters::Blend(color, mode));
125 }
126 }
127 }
128
paletteForColorHSV(SkColor color)129 static BitmapPalette paletteForColorHSV(SkColor color) {
130 float hsv[3];
131 SkColorToHSV(color, hsv);
132 return hsv[2] >= .5f ? BitmapPalette::Light : BitmapPalette::Dark;
133 }
134
filterPalette(const SkPaint * paint,BitmapPalette palette)135 static BitmapPalette filterPalette(const SkPaint* paint, BitmapPalette palette) {
136 if (palette == BitmapPalette::Unknown || !paint || !paint->getColorFilter()) {
137 return palette;
138 }
139
140 SkColor4f color = palette == BitmapPalette::Light ? SkColors::kWhite : SkColors::kBlack;
141 sk_sp<SkColorSpace> srgb = SkColorSpace::MakeSRGB();
142 color = paint->getColorFilter()->filterColor4f(color, srgb.get(), srgb.get());
143 return paletteForColorHSV(color.toSkColor());
144 }
145
transformPaint(ColorTransform transform,SkPaint * paint)146 bool transformPaint(ColorTransform transform, SkPaint* paint) {
147 // TODO
148 applyColorTransform(transform, *paint);
149 return true;
150 }
151
transformPaint(ColorTransform transform,SkPaint * paint,BitmapPalette palette)152 bool transformPaint(ColorTransform transform, SkPaint* paint, BitmapPalette palette) {
153 palette = filterPalette(paint, palette);
154 bool shouldInvert = false;
155 if (palette == BitmapPalette::Light && transform == ColorTransform::Dark) {
156 shouldInvert = true;
157 }
158 if (palette == BitmapPalette::Dark && transform == ColorTransform::Light) {
159 shouldInvert = true;
160 }
161 if (shouldInvert) {
162 SkHighContrastConfig config;
163 config.fInvertStyle = SkHighContrastConfig::InvertStyle::kInvertLightness;
164 paint->setColorFilter(SkHighContrastFilter::Make(config)->makeComposed(paint->refColorFilter()));
165 }
166 return shouldInvert;
167 }
168
169 } // namespace android::uirenderer
170