/*
* Copyright (C) 2008-2009 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.gesture;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.RectF;
import android.os.Parcel;
import android.os.Parcelable;
import android.util.Log;
import java.io.IOException;
import java.io.DataOutputStream;
import java.io.DataInputStream;
import java.io.ByteArrayOutputStream;
import java.io.ByteArrayInputStream;
import java.util.ArrayList;
import java.util.concurrent.atomic.AtomicInteger;
/**
* A gesture is a hand-drawn shape on a touch screen. It can have one or multiple strokes.
* Each stroke is a sequence of timed points. A user-defined gesture can be recognized by
* a GestureLibrary.
*/
public class Gesture implements Parcelable {
private static final long GESTURE_ID_BASE = System.currentTimeMillis();
private static final int BITMAP_RENDERING_WIDTH = 2;
private static final boolean BITMAP_RENDERING_ANTIALIAS = true;
private static final boolean BITMAP_RENDERING_DITHER = true;
private static final AtomicInteger sGestureCount = new AtomicInteger(0);
private final RectF mBoundingBox = new RectF();
// the same as its instance ID
private long mGestureID;
private final ArrayList<GestureStroke> mStrokes = new ArrayList<GestureStroke>();
public Gesture() {
mGestureID = GESTURE_ID_BASE + sGestureCount.incrementAndGet();
}
@Override
public Object clone() {
Gesture gesture = new Gesture();
gesture.mBoundingBox.set(mBoundingBox.left, mBoundingBox.top,
mBoundingBox.right, mBoundingBox.bottom);
final int count = mStrokes.size();
for (int i = 0; i < count; i++) {
GestureStroke stroke = mStrokes.get(i);
gesture.mStrokes.add((GestureStroke)stroke.clone());
}
return gesture;
}
/**
* @return all the strokes of the gesture
*/
public ArrayList<GestureStroke> getStrokes() {
return mStrokes;
}
/**
* @return the number of strokes included by this gesture
*/
public int getStrokesCount() {
return mStrokes.size();
}
/**
* Adds a stroke to the gesture.
*
* @param stroke
*/
public void addStroke(GestureStroke stroke) {
mStrokes.add(stroke);
mBoundingBox.union(stroke.boundingBox);
}
/**
* Calculates the total length of the gesture. When there are multiple strokes in
* the gesture, this returns the sum of the lengths of all the strokes.
*
* @return the length of the gesture
*/
public float getLength() {
int len = 0;
final ArrayList<GestureStroke> strokes = mStrokes;
final int count = strokes.size();
for (int i = 0; i < count; i++) {
len += strokes.get(i).length;
}
return len;
}
/**
* @return the bounding box of the gesture
*/
public RectF getBoundingBox() {
return mBoundingBox;
}
public Path toPath() {
return toPath(null);
}
public Path toPath(Path path) {
if (path == null) path = new Path();
final ArrayList<GestureStroke> strokes = mStrokes;
final int count = strokes.size();
for (int i = 0; i < count; i++) {
path.addPath(strokes.get(i).getPath());
}
return path;
}
public Path toPath(int width, int height, int edge, int numSample) {
return toPath(null, width, height, edge, numSample);
}
public Path toPath(Path path, int width, int height, int edge, int numSample) {
if (path == null) path = new Path();
final ArrayList<GestureStroke> strokes = mStrokes;
final int count = strokes.size();
for (int i = 0; i < count; i++) {
path.addPath(strokes.get(i).toPath(width - 2 * edge, height - 2 * edge, numSample));
}
return path;
}
/**
* Sets the id of the gesture.
*
* @param id
*/
void setID(long id) {
mGestureID = id;
}
/**
* @return the id of the gesture
*/
public long getID() {
return mGestureID;
}
/**
* Creates a bitmap of the gesture with a transparent background.
*
* @param width width of the target bitmap
* @param height height of the target bitmap
* @param edge the edge
* @param numSample
* @param color
* @return the bitmap
*/
public Bitmap toBitmap(int width, int height, int edge, int numSample, int color) {
final Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
final Canvas canvas = new Canvas(bitmap);
canvas.translate(edge, edge);
final Paint paint = new Paint();
paint.setAntiAlias(BITMAP_RENDERING_ANTIALIAS);
paint.setDither(BITMAP_RENDERING_DITHER);
paint.setColor(color);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeCap(Paint.Cap.ROUND);
paint.setStrokeWidth(BITMAP_RENDERING_WIDTH);
final ArrayList<GestureStroke> strokes = mStrokes;
final int count = strokes.size();
for (int i = 0; i < count; i++) {
Path path = strokes.get(i).toPath(width - 2 * edge, height - 2 * edge, numSample);
canvas.drawPath(path, paint);
}
return bitmap;
}
/**
* Creates a bitmap of the gesture with a transparent background.
*
* @param width
* @param height
* @param inset
* @param color
* @return the bitmap
*/
public Bitmap toBitmap(int width, int height, int inset, int color) {
final Bitmap bitmap = Bitmap.createBitmap(width, height,
Bitmap.Config.ARGB_8888);
final Canvas canvas = new Canvas(bitmap);
final Paint paint = new Paint();
paint.setAntiAlias(BITMAP_RENDERING_ANTIALIAS);
paint.setDither(BITMAP_RENDERING_DITHER);
paint.setColor(color);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeCap(Paint.Cap.ROUND);
paint.setStrokeWidth(BITMAP_RENDERING_WIDTH);
final Path path = toPath();
final RectF bounds = new RectF();
path.computeBounds(bounds, true);
final float sx = (width - 2 * inset) / bounds.width();
final float sy = (height - 2 * inset) / bounds.height();
final float scale = sx > sy ? sy : sx;
paint.setStrokeWidth(2.0f / scale);
path.offset(-bounds.left + (width - bounds.width() * scale) / 2.0f,
-bounds.top + (height - bounds.height() * scale) / 2.0f);
canvas.translate(inset, inset);
canvas.scale(scale, scale);
canvas.drawPath(path, paint);
return bitmap;
}
void serialize(DataOutputStream out) throws IOException {
final ArrayList<GestureStroke> strokes = mStrokes;
final int count = strokes.size();
// Write gesture ID
out.writeLong(mGestureID);
// Write number of strokes
out.writeInt(count);
for (int i = 0; i < count; i++) {
strokes.get(i).serialize(out);
}
}
static Gesture deserialize(DataInputStream in) throws IOException {
final Gesture gesture = new Gesture();
// Gesture ID
gesture.mGestureID = in.readLong();
// Number of strokes
final int count = in.readInt();
for (int i = 0; i < count; i++) {
gesture.addStroke(GestureStroke.deserialize(in));
}
return gesture;
}
public static final Parcelable.Creator<Gesture> CREATOR = new Parcelable.Creator<Gesture>() {
public Gesture createFromParcel(Parcel in) {
Gesture gesture = null;
final long gestureID = in.readLong();
final DataInputStream inStream = new DataInputStream(
new ByteArrayInputStream(in.createByteArray()));
try {
gesture = deserialize(inStream);
} catch (IOException e) {
Log.e(GestureConstants.LOG_TAG, "Error reading Gesture from parcel:", e);
} finally {
GestureUtils.closeStream(inStream);
}
if (gesture != null) {
gesture.mGestureID = gestureID;
}
return gesture;
}
public Gesture[] newArray(int size) {
return new Gesture[size];
}
};
public void writeToParcel(Parcel out, int flags) {
out.writeLong(mGestureID);
boolean result = false;
final ByteArrayOutputStream byteStream =
new ByteArrayOutputStream(GestureConstants.IO_BUFFER_SIZE);
final DataOutputStream outStream = new DataOutputStream(byteStream);
try {
serialize(outStream);
result = true;
} catch (IOException e) {
Log.e(GestureConstants.LOG_TAG, "Error writing Gesture to parcel:", e);
} finally {
GestureUtils.closeStream(outStream);
GestureUtils.closeStream(byteStream);
}
if (result) {
out.writeByteArray(byteStream.toByteArray());
}
}
public int describeContents() {
return 0;
}
}
|
