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authorTadashi G. Takaoka <takaoka@google.com>2010-12-02 03:07:43 -0800
committerAndroid (Google) Code Review <android-gerrit@google.com>2010-12-02 03:07:43 -0800
commit26dae3f4e8ffd0f25b78c58598752cd393419bcc (patch)
treefd7280e7e0c0c879958a5c7d8b9376942d447e9b /java/src/com/android/inputmethod/latin/SwipeTracker.java
parent18c28f431eadc1b451ca25d14fd683db4b234838 (diff)
parent5a309f57155fb95667c2ccdda730eaf175de8876 (diff)
downloadlatinime-26dae3f4e8ffd0f25b78c58598752cd393419bcc.tar.gz
latinime-26dae3f4e8ffd0f25b78c58598752cd393419bcc.tar.xz
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Merge "Move some inner static class to top class in new package"
Diffstat (limited to 'java/src/com/android/inputmethod/latin/SwipeTracker.java')
-rw-r--r--java/src/com/android/inputmethod/latin/SwipeTracker.java157
1 files changed, 0 insertions, 157 deletions
diff --git a/java/src/com/android/inputmethod/latin/SwipeTracker.java b/java/src/com/android/inputmethod/latin/SwipeTracker.java
deleted file mode 100644
index 970e91965..000000000
--- a/java/src/com/android/inputmethod/latin/SwipeTracker.java
+++ /dev/null
@@ -1,157 +0,0 @@
-/*
- * Copyright (C) 2010 Google Inc.
- *
- * 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 com.android.inputmethod.latin;
-
-import android.view.MotionEvent;
-
-class SwipeTracker {
- private static final int NUM_PAST = 4;
- private static final int LONGEST_PAST_TIME = 200;
-
- final EventRingBuffer mBuffer = new EventRingBuffer(NUM_PAST);
-
- private float mYVelocity;
- private float mXVelocity;
-
- public void addMovement(MotionEvent ev) {
- if (ev.getAction() == MotionEvent.ACTION_DOWN) {
- mBuffer.clear();
- return;
- }
- long time = ev.getEventTime();
- final int count = ev.getHistorySize();
- for (int i = 0; i < count; i++) {
- addPoint(ev.getHistoricalX(i), ev.getHistoricalY(i), ev.getHistoricalEventTime(i));
- }
- addPoint(ev.getX(), ev.getY(), time);
- }
-
- private void addPoint(float x, float y, long time) {
- final EventRingBuffer buffer = mBuffer;
- while (buffer.size() > 0) {
- long lastT = buffer.getTime(0);
- if (lastT >= time - LONGEST_PAST_TIME)
- break;
- buffer.dropOldest();
- }
- buffer.add(x, y, time);
- }
-
- public void computeCurrentVelocity(int units) {
- computeCurrentVelocity(units, Float.MAX_VALUE);
- }
-
- public void computeCurrentVelocity(int units, float maxVelocity) {
- final EventRingBuffer buffer = mBuffer;
- final float oldestX = buffer.getX(0);
- final float oldestY = buffer.getY(0);
- final long oldestTime = buffer.getTime(0);
-
- float accumX = 0;
- float accumY = 0;
- final int count = buffer.size();
- for (int pos = 1; pos < count; pos++) {
- final int dur = (int)(buffer.getTime(pos) - oldestTime);
- if (dur == 0) continue;
- float dist = buffer.getX(pos) - oldestX;
- float vel = (dist / dur) * units; // pixels/frame.
- if (accumX == 0) accumX = vel;
- else accumX = (accumX + vel) * .5f;
-
- dist = buffer.getY(pos) - oldestY;
- vel = (dist / dur) * units; // pixels/frame.
- if (accumY == 0) accumY = vel;
- else accumY = (accumY + vel) * .5f;
- }
- mXVelocity = accumX < 0.0f ? Math.max(accumX, -maxVelocity)
- : Math.min(accumX, maxVelocity);
- mYVelocity = accumY < 0.0f ? Math.max(accumY, -maxVelocity)
- : Math.min(accumY, maxVelocity);
- }
-
- public float getXVelocity() {
- return mXVelocity;
- }
-
- public float getYVelocity() {
- return mYVelocity;
- }
-
- static class EventRingBuffer {
- private final int bufSize;
- private final float xBuf[];
- private final float yBuf[];
- private final long timeBuf[];
- private int top; // points new event
- private int end; // points oldest event
- private int count; // the number of valid data
-
- public EventRingBuffer(int max) {
- this.bufSize = max;
- xBuf = new float[max];
- yBuf = new float[max];
- timeBuf = new long[max];
- clear();
- }
-
- public void clear() {
- top = end = count = 0;
- }
-
- public int size() {
- return count;
- }
-
- // Position 0 points oldest event
- private int index(int pos) {
- return (end + pos) % bufSize;
- }
-
- private int advance(int index) {
- return (index + 1) % bufSize;
- }
-
- public void add(float x, float y, long time) {
- xBuf[top] = x;
- yBuf[top] = y;
- timeBuf[top] = time;
- top = advance(top);
- if (count < bufSize) {
- count++;
- } else {
- end = advance(end);
- }
- }
-
- public float getX(int pos) {
- return xBuf[index(pos)];
- }
-
- public float getY(int pos) {
- return yBuf[index(pos)];
- }
-
- public long getTime(int pos) {
- return timeBuf[index(pos)];
- }
-
- public void dropOldest() {
- count--;
- end = advance(end);
- }
- }
-} \ No newline at end of file