1 /*
2  * Copyright (C) 2014 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 package com.android.camera.ui.motion;
18 
19 /**
20  * Predefined material curves and animations.
21  */
22 public class UnitCurves {
23     public static final UnitCurve FAST_OUT_SLOW_IN = new UnitBezier(0.4f, 0.0f, 0.2f, 1.0f);
24     public static final UnitCurve LINEAR_OUT_SLOW_IN = new UnitBezier(0.0f, 0.0f, 0.2f, 1.0f);
25     public static final UnitCurve FAST_OUT_LINEAR_IN = new UnitBezier(0.4f, 0.0f, 1.0f, 1.0f);
26     public static final UnitCurve LINEAR = new UnitBezier(0.0f, 0.0f, 1.0f, 1.0f);
27 
28     /**
29      * Given two curves (from and to) and a time along the from curve, compute
30      * the time at t, and find a t along the 'toCurve' that will produce the
31      * same output. This is useful when interpolating between two different curves
32      * when the animation is not at the beginning or end.
33      *
34      * @param enterCurve the curve to compute the value from
35      * @param exitCurve the curve to find a time t on that matches output of
36      *                  enterCurve at T.
37      * @param t the time at which to compute the value (0..1)
38      * @return the time along the exitCurve.
39      */
mapEnterCurveToExitCurveAtT(UnitCurve enterCurve, UnitCurve exitCurve, float t)40     public static float mapEnterCurveToExitCurveAtT(UnitCurve enterCurve, UnitCurve exitCurve,
41           float t) {
42         return exitCurve.tAt(1 - enterCurve.valueAt(t));
43     }
44 }
45