1 /*
2 * Copyright 2022 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 "DisplayConfig.h"
18
19 #include <unordered_map>
20
21 namespace aidl::android::hardware::graphics::composer3::impl {
22 namespace {
23
24 template <class T>
hashCombine(size_t & hash,const T & value)25 inline void hashCombine(size_t& hash, const T& value) {
26 std::hash<T> hasher;
27 hash ^= hasher(value) + 0x9e3779b9 + (hash << 6) + (hash >> 2);
28 }
29
30 } // namespace
31
setAttribute(DisplayAttribute attribute,int32_t value)32 void DisplayConfig::setAttribute(DisplayAttribute attribute, int32_t value) {
33 if (attribute == DisplayAttribute::WIDTH) {
34 mWidth = value;
35 }
36 if (attribute == DisplayAttribute::HEIGHT) {
37 mHeight = value;
38 }
39 if (attribute == DisplayAttribute::DPI_X) {
40 mDpiX = value;
41 }
42 if (attribute == DisplayAttribute::DPI_Y) {
43 mDpiY = value;
44 }
45 if (attribute == DisplayAttribute::VSYNC_PERIOD) {
46 mVsyncPeriodNanos = value;
47 }
48 if (attribute == DisplayAttribute::CONFIG_GROUP) {
49 mConfigGroup = value;
50 }
51 }
52
getAttribute(DisplayAttribute attribute) const53 int32_t DisplayConfig::getAttribute(DisplayAttribute attribute) const {
54 if (attribute == DisplayAttribute::WIDTH) {
55 return mWidth;
56 }
57 if (attribute == DisplayAttribute::HEIGHT) {
58 return mHeight;
59 }
60 if (attribute == DisplayAttribute::DPI_X) {
61 // From hwcomposer2.h, HWC2_ATTRIBUTE_DPI_X returns "Dots per thousand
62 // inches (DPI * 1000)".
63 return getDotsPerThousandInchesX();
64 }
65 if (attribute == DisplayAttribute::DPI_Y) {
66 // From hwcomposer2.h, HWC2_ATTRIBUTE_DPI_Y returns "Dots per thousand
67 // inches (DPI * 1000)"
68 return getDotsPerThousandInchesY();
69 }
70 if (attribute == DisplayAttribute::VSYNC_PERIOD) {
71 return mVsyncPeriodNanos;
72 }
73 if (attribute == DisplayAttribute::CONFIG_GROUP) {
74 return mConfigGroup;
75 }
76 return -1;
77 }
78
toString() const79 std::string DisplayConfig::toString() const {
80 std::string output;
81 output += " id: " + std::to_string(mId);
82 output += " w:" + std::to_string(mWidth);
83 output += " h:" + std::to_string(mHeight);
84 output += " dpi-x:" + std::to_string(mDpiX);
85 output += " dpi-y:" + std::to_string(mDpiY);
86 output += " vsync:" + std::to_string(1e9 / mVsyncPeriodNanos);
87 output += " config-group:" + std::to_string(mConfigGroup);
88 return output;
89 }
90
91 /*static*/
addConfigGroups(std::vector<DisplayConfig> * configs)92 void DisplayConfig::addConfigGroups(std::vector<DisplayConfig>* configs) {
93 // From /hardware/interfaces/graphics/composer/2.4/IComposerClient.hal:
94 // "Configurations which share the same config group are similar in all
95 // attributes except for the vsync period."
96 struct ConfigForGroupHash {
97 size_t operator()(const DisplayConfig& config) const {
98 size_t hash = 0;
99 hashCombine(hash, config.mWidth);
100 hashCombine(hash, config.mHeight);
101 hashCombine(hash, config.mDpiX);
102 hashCombine(hash, config.mDpiY);
103 return hash;
104 }
105 };
106 struct ConfigForGroupEq {
107 size_t operator()(const DisplayConfig& a, const DisplayConfig& b) const {
108 if (a.mWidth != b.mWidth) {
109 return a.mWidth < b.mWidth;
110 }
111 if (a.mHeight != b.mHeight) {
112 return a.mHeight < b.mHeight;
113 }
114 if (a.mDpiX != b.mDpiX) {
115 return a.mDpiX < b.mDpiX;
116 }
117 return a.mDpiY < b.mDpiY;
118 }
119 };
120
121 std::unordered_map<DisplayConfig, int32_t, ConfigForGroupHash,
122 ConfigForGroupEq>
123 configToConfigGroup;
124
125 for (auto& config : *configs) {
126 auto [it, inserted] =
127 configToConfigGroup.try_emplace(config, configToConfigGroup.size());
128 config.setConfigGroup(it->second);
129 }
130 }
131
132 } // namespace aidl::android::hardware::graphics::composer3::impl
133