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 <utils/Flattenable.h> 20 #include "FloatRect.h" 21 22 #include <math.h> 23 #include <type_traits> 24 25 namespace android { 26 27 struct StretchEffect : public LightFlattenablePod<StretchEffect> { 28 constexpr static const float CONTENT_DISTANCE_STRETCHED = 1.f; 29 30 float width = 0; 31 float height = 0; 32 float vectorX = 0; 33 float vectorY = 0; 34 float maxAmountX = 0; 35 float maxAmountY = 0; 36 FloatRect mappedChildBounds = {0, 0, 0, 0}; 37 38 bool operator==(const StretchEffect& other) const { 39 return width == other.width && height == other.height && 40 vectorX == other.vectorX && 41 vectorY == other.vectorY && 42 maxAmountX == other.maxAmountX && 43 maxAmountY == other.maxAmountY && 44 mappedChildBounds == other.mappedChildBounds; 45 } 46 isZeroStretchEffect47 static bool isZero(float value) { 48 constexpr float NON_ZERO_EPSILON = 0.001f; 49 return fabsf(value) <= NON_ZERO_EPSILON; 50 } 51 isNoOpStretchEffect52 bool isNoOp() const { return isZero(vectorX) && isZero(vectorY); } 53 hasEffectStretchEffect54 bool hasEffect() const { return !isNoOp(); } 55 sanitizeStretchEffect56 void sanitize() { 57 // If the area is empty, or the max amount is zero, then reset back to defaults 58 if (width == 0.f || height == 0.f || isZero(maxAmountX) || 59 isZero(maxAmountY)) { 60 *this = StretchEffect{}; 61 } 62 } 63 getStretchWidthMultiplierStretchEffect64 float getStretchWidthMultiplier() const { 65 return CONTENT_DISTANCE_STRETCHED / (1.f + abs(vectorX)); 66 } 67 getStretchHeightMultiplierStretchEffect68 float getStretchHeightMultiplier() const { 69 return CONTENT_DISTANCE_STRETCHED / (1.f + abs(vectorY)); 70 } 71 }; 72 73 static_assert(std::is_trivially_copyable<StretchEffect>::value, 74 "StretchEffect must be trivially copyable to be flattenable"); 75 76 } // namespace android