/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
* in compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License
* is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
* or implied. See the License for the specific language governing permissions and limitations under
* the License.
*/
package android.support.v17.leanback.animation;
import android.animation.TimeInterpolator;
/**
* @hide
*/
public class LogDecelerateInterpolator implements TimeInterpolator {
int mBase;
int mDrift;
final float mLogScale;
public LogDecelerateInterpolator(int base, int drift) {
mBase = base;
mDrift = drift;
mLogScale = 1f / computeLog(1, mBase, mDrift);
}
static float computeLog(float t, int base, int drift) {
return (float) -Math.pow(base, -t) + 1 + (drift * t);
}
@Override
public float getInterpolation(float t) {
return computeLog(t, mBase, mDrift) * mLogScale;
}
}