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Improve internal algorithm for SwipeGesture

Browse source 
but still under question
This commit is contained in:
Pavel fljot 2012-07-11 22:47:55 +03:00
parent 850ed9849f
commit 4a8e6feada
1 changed files with 21 additions and 19 deletions
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40
src/org/gestouch/gestures/SwipeGesture.as
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@ -1,5 +1,6 @@
package org.gestouch.gestures
{
import org.gestouch.utils.GestureUtils;
import org.gestouch.core.GestureState;
import org.gestouch.core.Touch;
import org.gestouch.events.SwipeGestureEvent;
@ -20,12 +21,13 @@ package org.gestouch.gestures
*/
public class SwipeGesture extends Gesture
{
private static const ANGLE:Number = 30 * GestureUtils.DEGREES_TO_RADIANS;
public var slop:Number = Gesture.DEFAULT_SLOP;
public var numTouchesRequired:uint = 1;
public var minVelocity:Number = 0.8;
public var minVelocity:Number = 0.6;
public var minOffset:Number = Gesture.DEFAULT_SLOP;
public var direction:uint = SwipeGestureDirection.ORTHOGONAL;
public var maxDirectionalOffset:Number = Gesture.DEFAULT_SLOP << 1;
protected var _offset:Point = new Point();
protected var _startTime:int;
@ -103,6 +105,10 @@ package org.gestouch.gestures
if (touchesCount < numTouchesRequired)
return;
var totalTime:int = touch.time - _startTime;
if (totalTime == 0)
return;//It was somehow THAT MUCH performant on one Android tablet
var prevCentralPointX:Number = _centralPoint.x;
var prevCentralPointY:Number = _centralPoint.y;
updateCentralPoint();
@ -110,28 +116,27 @@ package org.gestouch.gestures
_offset.x = _centralPoint.x - _location.x;
_offset.y = _centralPoint.y - _location.y;
var offsetLength:Number = _offset.length;
if (offsetLength < slop)
{
// no need in processing - we're in the very beginning of movement
// no need in processing yet - we're in the very beginning of movement
return;
}
// average velocity (total offset to total duration)
_prevAvrgVel.x = _avrgVel.x;
_prevAvrgVel.y = _avrgVel.y;
var absPrevAvrgVel:Number = _prevAvrgVel.length;
var totalTime:int = touch.time - _startTime;
_avrgVel.x = _offset.x / totalTime;
_avrgVel.y = _offset.y / totalTime;
var avrgVel:Number = _avrgVel.length;
if (avrgVel * 0.95 < absPrevAvrgVel)
if (avrgVel * 0.95 < _prevAvrgVel.length)
{
_decelerationCounter++;
}
if (_decelerationCounter > 5 || avrgVel < 0.1)
// We should quickly fail if we have noticable deceleration
// or average velocity is too low
if (_decelerationCounter > 5 || avrgVel < 0.05)
{
setState(GestureState.FAILED);
return;
@ -139,9 +144,6 @@ package org.gestouch.gestures
if (_noDirection)
{
// We should quickly fail if we have noticable deceleration
// or first movement happend way later after touch
if (avrgVel >= minVelocity && (minOffset != minOffset || offsetLength >= minOffset))
{
if (setState(GestureState.RECOGNIZED) && hasEventListener(SwipeGestureEvent.GESTURE_SWIPE))
@ -169,9 +171,9 @@ package org.gestouch.gestures
// horizontal velocity is greater then vertical, but we're not interested in any horizontal direction
setState(GestureState.FAILED);
}
else if (recentOffsetX < 0 && (direction & SwipeGestureDirection.LEFT) == 0 ||
recentOffsetX > 0 && (direction & SwipeGestureDirection.RIGHT) == 0 ||
Math.abs(_offset.y) > maxDirectionalOffset)
else if ((recentOffsetX < 0 && (direction & SwipeGestureDirection.LEFT) == 0) ||
(recentOffsetX > 0 && (direction & SwipeGestureDirection.RIGHT) == 0) ||
Math.abs(Math.atan(_offset.y/_offset.x)) > ANGLE)
{
// movement in opposite direction
// or too much diagonally
@ -197,9 +199,9 @@ package org.gestouch.gestures
// horizontal velocity is greater then vertical, but we're not interested in any horizontal direction
setState(GestureState.FAILED);
}
else if (recentOffsetY < 0 && (direction & SwipeGestureDirection.UP) == 0 ||
recentOffsetY > 0 && (direction & SwipeGestureDirection.DOWN) == 0 ||
Math.abs(_offset.x) > maxDirectionalOffset)
else if ((recentOffsetY < 0 && (direction & SwipeGestureDirection.UP) == 0) ||
(recentOffsetY > 0 && (direction & SwipeGestureDirection.DOWN) == 0) ||
Math.abs(Math.atan(_offset.x/_offset.y)) > ANGLE)
{
// movement in opposite direction
// or too much diagonally
@ -221,7 +223,7 @@ package org.gestouch.gestures
setState(GestureState.FAILED);
}
}
}
}
override protected function onTouchEnd(touch:Touch):void