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