1 /*
2  * Copyright (C) 2024 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 package com.android.internal.widget.remotecompose.core.operations.utilities.easing;
17 
18 /**
19  * Provide a bouncing Easing function
20  */
21 public class ElasticOutCurve extends Easing {
22     private static final float F_PI = (float) Math.PI;
23     private static final float C4 = 2 * F_PI / 3;
24     private static final float TWENTY_PI = 20 * F_PI;
25     private static final float LOG_8 = (float) Math.log(8.0f);
26 
27     @Override
get(float x)28     public float get(float x) {
29         if (x <= 0) {
30             return 0.0f;
31         }
32         if (x >= 1) {
33             return 1.0f;
34         } else
35             return (float) (Math.pow(2.0f, -10 * x)
36                     * Math.sin((x * 10 - 0.75f) * C4) + 1);
37     }
38 
39     @Override
getDiff(float x)40     public float getDiff(float x) {
41         if (x < 0 || x > 1) {
42             return 0.0f;
43         } else
44             return (float) ((5 * Math.pow(2.0f, (1 - 10 * x))
45                     * (LOG_8 * Math.cos(TWENTY_PI * x / 3) + 2
46                     * F_PI * Math.sin(TWENTY_PI * x / 3))
47                     / 3));
48     }
49 }
50