diff options
Diffstat (limited to 'java/src')
| -rw-r--r-- | java/src/com/android/inputmethod/latin/LatinKeyboardBaseView.java | 1 | ||||
| -rw-r--r-- | java/src/com/android/inputmethod/latin/SwipeTracker.java | 157 |
2 files changed, 91 insertions, 67 deletions
diff --git a/java/src/com/android/inputmethod/latin/LatinKeyboardBaseView.java b/java/src/com/android/inputmethod/latin/LatinKeyboardBaseView.java index 7247632c3..346daa3e3 100644 --- a/java/src/com/android/inputmethod/latin/LatinKeyboardBaseView.java +++ b/java/src/com/android/inputmethod/latin/LatinKeyboardBaseView.java @@ -1286,7 +1286,6 @@ public class LatinKeyboardBaseView extends View implements View.OnClickListener } // Track the last few movements to look for spurious swipes. - if (action == MotionEvent.ACTION_DOWN) mSwipeTracker.clear(); mSwipeTracker.addMovement(me); // Ignore all motion events until a DOWN. diff --git a/java/src/com/android/inputmethod/latin/SwipeTracker.java b/java/src/com/android/inputmethod/latin/SwipeTracker.java index 007c8e7a4..31f7cb324 100644 --- a/java/src/com/android/inputmethod/latin/SwipeTracker.java +++ b/java/src/com/android/inputmethod/latin/SwipeTracker.java @@ -16,70 +16,40 @@ package com.android.inputmethod.latin; +import android.util.Log; import android.view.MotionEvent; class SwipeTracker { + private static final int NUM_PAST = 4; + private static final int LONGEST_PAST_TIME = 200; - static final int NUM_PAST = 4; - static final int LONGEST_PAST_TIME = 200; + final EventRingBuffer mBuffer = new EventRingBuffer(NUM_PAST); - final float mPastX[] = new float[NUM_PAST]; - final float mPastY[] = new float[NUM_PAST]; - final long mPastTime[] = new long[NUM_PAST]; - - float mYVelocity; - float mXVelocity; - - public void clear() { - mPastTime[0] = 0; - } + private float mYVelocity; + private float mXVelocity; public void addMovement(MotionEvent ev) { if (ev.getAction() == MotionEvent.ACTION_DOWN) { - clear(); + mBuffer.clear(); return; } long time = ev.getEventTime(); - final int N = ev.getHistorySize(); - for (int i=0; i<N; i++) { - addPoint(ev.getHistoricalX(i), ev.getHistoricalY(i), - ev.getHistoricalEventTime(i)); + 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) { - int drop = -1; - int i; - final long[] pastTime = mPastTime; - for (i=0; i<NUM_PAST; i++) { - if (pastTime[i] == 0) { + final EventRingBuffer buffer = mBuffer; + while (buffer.size() > 0) { + long lastT = buffer.getTime(0); + if (lastT >= time - LONGEST_PAST_TIME) break; - } else if (pastTime[i] < time-LONGEST_PAST_TIME) { - drop = i; - } - } - if (i == NUM_PAST && drop < 0) { - drop = 0; - } - if (drop == i) drop--; - final float[] pastX = mPastX; - final float[] pastY = mPastY; - if (drop >= 0) { - final int start = drop+1; - final int count = NUM_PAST-drop-1; - System.arraycopy(pastX, start, pastX, 0, count); - System.arraycopy(pastY, start, pastY, 0, count); - System.arraycopy(pastTime, start, pastTime, 0, count); - i -= (drop+1); - } - pastX[i] = x; - pastY[i] = y; - pastTime[i] = time; - i++; - if (i < NUM_PAST) { - pastTime[i] = 0; + buffer.dropOldest(); } + buffer.add(x, y, time); } public void computeCurrentVelocity(int units) { @@ -87,33 +57,24 @@ class SwipeTracker { } public void computeCurrentVelocity(int units, float maxVelocity) { - final float[] pastX = mPastX; - final float[] pastY = mPastY; - final long[] pastTime = mPastTime; + final EventRingBuffer buffer = mBuffer; + final float oldestX = buffer.getX(0); + final float oldestY = buffer.getY(0); + final long oldestTime = buffer.getTime(0); - final float oldestX = pastX[0]; - final float oldestY = pastY[0]; - final long oldestTime = pastTime[0]; float accumX = 0; float accumY = 0; - int N=0; - while (N < NUM_PAST) { - if (pastTime[N] == 0) { - break; - } - N++; - } - - for (int i=1; i < N; i++) { - final int dur = (int)(pastTime[i] - oldestTime); + 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 = pastX[i] - oldestX; - float vel = (dist/dur) * units; // pixels/frame. + float dist = buffer.getX(pos) - oldestX; + float vel = (dist / dur) * units; // pixels/frame. if (accumX == 0) accumX = vel; else accumX = (accumX + vel) * .5f; - dist = pastY[i] - oldestY; - vel = (dist/dur) * units; // pixels/frame. + dist = buffer.getY(pos) - oldestY; + vel = (dist / dur) * units; // pixels/frame. if (accumY == 0) accumY = vel; else accumY = (accumY + vel) * .5f; } @@ -130,4 +91,68 @@ class SwipeTracker { 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); + } + } }
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