1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except 5 * in compliance with the License. You may obtain a copy of the License at 6 * 7 * http://www.apache.org/licenses/LICENSE-2.0 8 * 9 * Unless required by applicable law or agreed to in writing, software distributed under the License 10 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express 11 * or implied. See the License for the specific language governing permissions and limitations under 12 * the License. 13 */ 14 15 package com.android.inputmethod.keyboard.internal; 16 17 import com.android.inputmethod.latin.ResizableIntArray; 18 19 public final class GestureStrokeWithPreviewPoints extends GestureStroke { 20 public static final int PREVIEW_CAPACITY = 256; 21 22 private final ResizableIntArray mPreviewEventTimes = new ResizableIntArray(PREVIEW_CAPACITY); 23 private final ResizableIntArray mPreviewXCoordinates = new ResizableIntArray(PREVIEW_CAPACITY); 24 private final ResizableIntArray mPreviewYCoordinates = new ResizableIntArray(PREVIEW_CAPACITY); 25 26 private int mStrokeId; 27 private int mLastPreviewSize; 28 29 private int mMinPreviewSampleLengthSquare; 30 private int mLastX; 31 private int mLastY; 32 33 // TODO: Move this to resource. 34 private static final float MIN_PREVIEW_SAMPLE_LENGTH_RATIO_TO_KEY_WIDTH = 0.1f; 35 GestureStrokeWithPreviewPoints(final int pointerId, final GestureStrokeParams params)36 public GestureStrokeWithPreviewPoints(final int pointerId, final GestureStrokeParams params) { 37 super(pointerId, params); 38 } 39 40 @Override reset()41 protected void reset() { 42 super.reset(); 43 mStrokeId++; 44 mLastPreviewSize = 0; 45 mPreviewEventTimes.setLength(0); 46 mPreviewXCoordinates.setLength(0); 47 mPreviewYCoordinates.setLength(0); 48 } 49 getGestureStrokeId()50 public int getGestureStrokeId() { 51 return mStrokeId; 52 } 53 getGestureStrokePreviewSize()54 public int getGestureStrokePreviewSize() { 55 return mPreviewEventTimes.getLength(); 56 } 57 58 @Override setKeyboardGeometry(final int keyWidth)59 public void setKeyboardGeometry(final int keyWidth) { 60 super.setKeyboardGeometry(keyWidth); 61 final float sampleLength = keyWidth * MIN_PREVIEW_SAMPLE_LENGTH_RATIO_TO_KEY_WIDTH; 62 mMinPreviewSampleLengthSquare = (int)(sampleLength * sampleLength); 63 } 64 needsSampling(final int x, final int y)65 private boolean needsSampling(final int x, final int y) { 66 final int dx = x - mLastX; 67 final int dy = y - mLastY; 68 return dx * dx + dy * dy >= mMinPreviewSampleLengthSquare; 69 } 70 71 @Override addPoint(final int x, final int y, final int time, final boolean isMajorEvent)72 public void addPoint(final int x, final int y, final int time, final boolean isMajorEvent) { 73 super.addPoint(x, y, time, isMajorEvent); 74 if (isMajorEvent || needsSampling(x, y)) { 75 mPreviewEventTimes.add(time); 76 mPreviewXCoordinates.add(x); 77 mPreviewYCoordinates.add(y); 78 mLastX = x; 79 mLastY = y; 80 } 81 } 82 appendPreviewStroke(final ResizableIntArray eventTimes, final ResizableIntArray xCoords, final ResizableIntArray yCoords)83 public void appendPreviewStroke(final ResizableIntArray eventTimes, 84 final ResizableIntArray xCoords, final ResizableIntArray yCoords) { 85 final int length = mPreviewEventTimes.getLength() - mLastPreviewSize; 86 if (length <= 0) { 87 return; 88 } 89 eventTimes.append(mPreviewEventTimes, mLastPreviewSize, length); 90 xCoords.append(mPreviewXCoordinates, mLastPreviewSize, length); 91 yCoords.append(mPreviewYCoordinates, mLastPreviewSize, length); 92 mLastPreviewSize = mPreviewEventTimes.getLength(); 93 } 94 } 95