1 /* 2 * Copyright 2021 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 #pragma once 18 19 #include <cstdint> 20 21 #include <ftl/cast.h> 22 #include <ftl/string.h> 23 #include <log/log.h> 24 25 namespace android::ui { 26 27 // A LayerStack identifies a Z-ordered group of layers. A layer can only be associated to a single 28 // LayerStack, but a LayerStack can be associated to multiple displays, mirroring the same content. 29 struct LayerStack { 30 uint32_t id = UINT32_MAX; 31 32 template <typename T> fromValueLayerStack33 static constexpr LayerStack fromValue(T v) { 34 if (ftl::cast_safety<uint32_t>(v) == ftl::CastSafety::kSafe) { 35 return {static_cast<uint32_t>(v)}; 36 } 37 38 ALOGW("Invalid layer stack %s", ftl::to_string(v).c_str()); 39 return {}; 40 } 41 }; 42 43 constexpr LayerStack INVALID_LAYER_STACK; 44 constexpr LayerStack DEFAULT_LAYER_STACK{0u}; 45 46 inline bool operator==(LayerStack lhs, LayerStack rhs) { 47 return lhs.id == rhs.id; 48 } 49 50 inline bool operator!=(LayerStack lhs, LayerStack rhs) { 51 return !(lhs == rhs); 52 } 53 54 inline bool operator>(LayerStack lhs, LayerStack rhs) { 55 return lhs.id > rhs.id; 56 } 57 58 inline bool operator<(LayerStack lhs, LayerStack rhs) { 59 return lhs.id < rhs.id; 60 } 61 62 // A LayerFilter determines if a layer is included for output to a display. 63 struct LayerFilter { 64 LayerStack layerStack; 65 66 // True if the layer is only output to internal displays, i.e. excluded from screenshots, screen 67 // recordings, and mirroring to virtual or external displays. Used for display cutout overlays. 68 bool toInternalDisplay = false; 69 70 // Returns true if the input filter can be output to this filter. includesLayerFilter71 bool includes(LayerFilter other) const { 72 // The layer stacks must match. 73 if (other.layerStack == INVALID_LAYER_STACK || other.layerStack != layerStack) { 74 return false; 75 } 76 77 // The output must be to an internal display if the input filter has that constraint. 78 return !other.toInternalDisplay || toInternalDisplay; 79 } 80 }; 81 82 } // namespace android::ui 83