Android/frameworks_base
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

VelocityTracker now uses pointer id instead of index when referring to

Browse Source 
multiple pointers. VelocityTracker now correctly handles
multitouch. Addresses http://b/issue?id=2439030
This commit is contained in:
Adam Powell
2010-02-12 16:50:19 -08:00
parent 60d21566fc
commit 73d8fca6ba
1 changed files with 38 additions and 23 deletions
Download Patch File Download Diff File Expand all files Collapse all files

61
core/java/android/view/VelocityTracker.java
View File

@@ -124,24 +124,37 @@ public final class VelocityTracker implements Poolable<VelocityTracker> {
* @param ev The MotionEvent you received and would like to track.
*/
public void addMovement(MotionEvent ev) {
long time = ev.getEventTime();
final int N = ev.getHistorySize();
final int pointerCount = ev.getPointerCount();
for (int p = 0; p < pointerCount; p++) {
for (int i=0; i<N; i++) {
addPoint(p, ev.getHistoricalX(p, i), ev.getHistoricalY(p, i),
ev.getHistoricalEventTime(i));
int touchIndex = (mLastTouch + 1) % NUM_PAST;
for (int i=0; i<N; i++) {
for (int id = 0; id < MotionEvent.BASE_AVAIL_POINTERS; id++) {
mPastTime[id][touchIndex] = 0;
}
for (int p = 0; p < pointerCount; p++) {
int id = ev.getPointerId(p);
mPastX[id][touchIndex] = ev.getHistoricalX(p, i);
mPastY[id][touchIndex] = ev.getHistoricalY(p, i);
mPastTime[id][touchIndex] = ev.getHistoricalEventTime(i);
}
addPoint(p, ev.getX(p), ev.getY(p), time);
}
}
private void addPoint(int pos, float x, float y, long time) {
final int lastTouch = (mLastTouch + 1) % NUM_PAST;
mPastX[pos][lastTouch] = x;
mPastY[pos][lastTouch] = y;
mPastTime[pos][lastTouch] = time;
mLastTouch = lastTouch;
touchIndex = (touchIndex + 1) % NUM_PAST;
}
// During calculation any pointer values with a time of 0 are treated
// as a break in input. Initialize all to 0 for each new touch index.
for (int id = 0; id < MotionEvent.BASE_AVAIL_POINTERS; id++) {
mPastTime[id][touchIndex] = 0;
}
final long time = ev.getEventTime();
for (int p = 0; p < pointerCount; p++) {
int id = ev.getPointerId(p);
mPastX[id][touchIndex] = ev.getX(p);
mPastY[id][touchIndex] = ev.getY(p);
mPastTime[id][touchIndex] = time;
}
mLastTouch = touchIndex;
}
/**
@@ -177,10 +190,12 @@ public final class VelocityTracker implements Poolable<VelocityTracker> {
// find oldest acceptable time
int oldestTouch = lastTouch;
if (pastTime[lastTouch] > 0) { // cleared ?
oldestTouch = (lastTouch + 1) % NUM_PAST;
final float acceptableTime = pastTime[lastTouch] - LONGEST_PAST_TIME;
while (pastTime[oldestTouch] < acceptableTime) {
oldestTouch = (oldestTouch + 1) % NUM_PAST;
int nextOldestTouch = (NUM_PAST + oldestTouch - 1) % NUM_PAST;
while (pastTime[nextOldestTouch] >= acceptableTime &&
nextOldestTouch != lastTouch) {
oldestTouch = nextOldestTouch;
nextOldestTouch = (NUM_PAST + oldestTouch - 1) % NUM_PAST;
}
}
@@ -241,25 +256,25 @@ public final class VelocityTracker implements Poolable<VelocityTracker> {
* Retrieve the last computed X velocity. You must first call
* {@link #computeCurrentVelocity(int)} before calling this function.
*
* @param pos Which pointer's velocity to return.
* @param id Which pointer's velocity to return.
* @return The previously computed X velocity.
*
* @hide Pending API approval
*/
public float getXVelocity(int pos) {
return mXVelocity[pos];
public float getXVelocity(int id) {
return mXVelocity[id];
}
/**
* Retrieve the last computed Y velocity. You must first call
* {@link #computeCurrentVelocity(int)} before calling this function.
*
* @param pos Which pointer's velocity to return.
* @param id Which pointer's velocity to return.
* @return The previously computed Y velocity.
*
* @hide Pending API approval
*/
public float getYVelocity(int pos) {
return mYVelocity[pos];
public float getYVelocity(int id) {
return mYVelocity[id];
}
}