--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/mulwidgets/gesturehelper/src/gesture.cpp Thu Dec 17 08:56:02 2009 +0200
@@ -0,0 +1,931 @@
+/*
+* Copyright (c) 2008-2008 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description: Gesture class
+*
+*/
+
+#include "gesture.h"
+
+#include <e32math.h>
+
+#include "gesturedefs.h"
+#include "utils.h"
+
+using namespace GestureHelper;
+
+/**
+ * Point array for which only x axis is relevant
+ */
+class TXAxisPointArray : public TPointArray
+ {
+public:
+ TXAxisPointArray( const RArray< TPointEntry >& aPoints )
+ : TPointArray( aPoints ) {}
+
+ // from TPointArray
+ TPoint operator[]( TInt aIndex ) const
+ {
+ return TPoint( Raw( aIndex ).iX, 0 );
+ }
+ };
+
+/**
+ * Point array for which only y axis is relevant
+ */
+class TYAxisPointArray : public TPointArray
+ {
+public:
+ TYAxisPointArray( const RArray< TPointEntry >& aPoints )
+ : TPointArray( aPoints ) {}
+
+ // from TPointArray
+ TPoint operator[]( TInt aIndex ) const
+ {
+ return TPoint( 0, Raw( aIndex ).iY );
+ }
+ };
+
+namespace
+ {
+ /** @return the current time */
+ TTime CurrentTime()
+ {
+ TTime time;
+ time.UniversalTime();
+ return time;
+ }
+
+ /**
+ * @param aRelevantAxis See @ref MGestureEvent::Code
+ * @return gesture code by analysing the sequence of points
+ */
+ TGestureCode CodeFromPoints( const RArray< TPointEntry >& aPoints,
+ MGestureEvent::TAxis aRelevantAxis )
+ {
+ // select the correct filter based on aRelevantAxis
+ // these filter_ objects are array decorators that will eliminate either
+ // x, y or neither coordinate of each point
+ TXAxisPointArray filterY( aPoints );
+ TYAxisPointArray filterX( aPoints );
+ TPointArray filterNone( aPoints );
+ TPointArray& filter =
+ aRelevantAxis == MGestureEvent::EAxisHorizontal ? static_cast< TPointArray& >( filterY ) :
+ aRelevantAxis == MGestureEvent::EAxisVertical ? static_cast< TPointArray& >( filterX ) :
+ /* otherwise EAxisBoth */ filterNone;
+
+ // currently the gesture recogniser does not have any state, so it is fast
+ // to instantiate. The call is not static however, to allow the recogniser
+ // to be replaced by a more complicated implementation that has state.
+ // then it may make sense to make the recogniser a member variable.
+ return TGestureRecogniser().GestureCode( filter, aRelevantAxis );
+ }
+
+ /**
+ * @param aPoints Sequence of points representing 1st pointer movement
+ * @param aSecondaryPoints Sequence of points representing 2nd pointer movement
+ * @param aPreviousDistance contains the previous distance aftre this function execution
+ * @return gesture code by analysing the sequence of points
+ */
+ TGestureCode MultiTouchCode( const RArray< TPointEntry >& aPoints,
+ const RArray< TPointEntry >& aSecondaryPoints, TInt aPreviousDistance, TBool aIsFirstPinch )
+ {
+ TPointArray filter(aPoints);
+ TPointArray secondaryFilter(aSecondaryPoints);
+ return TGestureRecogniser().MultiTouchGestureCode( filter, secondaryFilter, aPreviousDistance, aIsFirstPinch );
+ }
+ } // unnamed namespace
+
+// ----------------------------------------------------------------------------
+// constructor
+// ----------------------------------------------------------------------------
+//
+CGesture::CGesture()
+ {
+ iPinchStartDistance = -1;
+ iPinchEndDistance = -1;
+ iPinchDetected = EFalse ;
+ }
+
+// ----------------------------------------------------------------------------
+// destructor
+// ----------------------------------------------------------------------------
+//
+CGesture::~CGesture()
+ {
+ iPoints.Close();
+ iSecondaryPoints.Close();
+ }
+
+// ----------------------------------------------------------------------------
+// AsStartEventL
+// ----------------------------------------------------------------------------
+//
+CGesture* CGesture::AsStartEventLC() const
+ {
+ __ASSERT_DEBUG( 0 < iPoints.Count(), Panic( EGesturePanicIllegalLogic ) );
+ CGesture* gesture = new ( ELeave ) CGesture;
+ CleanupStack::PushL( gesture );
+ User::LeaveIfError( gesture->AddPoint( iPoints[0].iPos ) );
+ return gesture;
+ }
+
+// ----------------------------------------------------------------------------
+// ResetToLastPoint
+// ----------------------------------------------------------------------------
+//
+void CGesture::ResetToLastPoint(TBool aSetPointerZero,TBool aSetToZero)
+ {
+ TPointEntry lastEntry(TPoint(0,0),TTime());
+ if( aSetToZero )
+ {
+ __ASSERT_DEBUG( 0 < iPoints.Count(), Panic( EGesturePanicIllegalLogic ) );
+ lastEntry = LastPoint( iPoints);
+ }
+ else
+ {
+ __ASSERT_DEBUG( 0 < iSecondaryPoints.Count(), Panic( EGesturePanicIllegalLogic ) );
+ lastEntry = LastPoint( iSecondaryPoints);
+ }
+ Reset();
+ if( aSetPointerZero )
+ {
+ iPoints.Append(lastEntry);
+ }
+ else
+ {
+ iSecondaryPoints.Append(lastEntry);
+ }
+ }
+
+// ----------------------------------------------------------------------------
+// LastPoint
+// ----------------------------------------------------------------------------
+//
+inline const TPointEntry CGesture::LastPoint( const RArray< TPointEntry >& aPoints ) const
+ {
+ return aPoints[aPoints.Count() - 1];
+ }
+
+// ----------------------------------------------------------------------------
+// IsPinchToleranceHigh
+// ----------------------------------------------------------------------------
+//
+inline TBool CGesture::IsHighPinchTolerance() const
+ {
+
+ if( iPinchEndDistance == -1 )
+ {
+ return ETrue;
+ }
+ else
+ {
+ TInt currentDistance = TGestureRecogniser().Length( LastPoint(iPoints).iPos, LastPoint(iSecondaryPoints).iPos );
+ // if previously zooming out and current distance corresponds to zooming in or viceversa
+ if( ( iZoomState == EZoomOut && currentDistance < iPinchStartDistance) ||
+ ( iZoomState == EZoomIn && currentDistance > iPinchStartDistance))
+ {
+ return ETrue;
+ }
+ }
+ return EFalse;
+ }
+// ----------------------------------------------------------------------------
+// Reset
+// ----------------------------------------------------------------------------
+//
+void CGesture::Reset()
+ {
+ iPoints.Reset();
+ iSecondaryPoints.Reset();
+ iHoldingState = ENotHolding;
+ iState = ENotActive;
+ iHoldingPointIndex = 0;
+ iVisual = NULL;
+ iIsDoubleTap = EFalse;
+ iPinchStartDistance = -1;
+ iPinchEndDistance = -1;
+ iPinchDetected = EFalse;
+ iZoomState = ENoZoom;
+ }
+
+// ----------------------------------------------------------------------------
+// IsEmpty
+// ----------------------------------------------------------------------------
+//
+TBool CGesture::IsEmpty() const
+ {
+ return iPoints.Count() == 0;
+ }
+
+// ----------------------------------------------------------------------------
+// IsMultiTouch
+// ----------------------------------------------------------------------------
+//
+TBool CGesture::IsMultiTouch() const
+ {
+ return iSecondaryPoints.Count() == 0;
+ }
+
+// ----------------------------------------------------------------------------
+// Add a point to the sequence of points that together make up the gesture
+// ----------------------------------------------------------------------------
+//
+TInt CGesture::AddPoint( const TPoint& aPoint )
+ {
+ if ( !IsLatestPoint( aPoint ) )
+ {
+ return iPoints.Append( TPointEntry( aPoint, CurrentTime() ) );
+ }
+ return KErrNone;
+ }
+
+// ----------------------------------------------------------------------------
+// AddSecondaryPoint
+// ----------------------------------------------------------------------------
+//
+TInt CGesture::AddSecondaryPoint( const TPoint& aPoint )
+ {
+ if ( !IsLatestSecondaryPoint( aPoint ) )
+ {
+ return iSecondaryPoints.Append( TPointEntry( aPoint, CurrentTime() ) );
+ }
+ return KErrNone;
+ }
+
+// ----------------------------------------------------------------------------
+// SetVisual
+// ----------------------------------------------------------------------------
+//
+void CGesture::SetVisual( CAlfVisual* aVisual )
+ {
+ iVisual = aVisual;
+ }
+
+// ----------------------------------------------------------------------------
+// IsNearHoldingPoint
+// ----------------------------------------------------------------------------
+//
+TBool CGesture::IsNearHoldingPoint( const TPoint& aPoint ) const
+ {
+ return ToleranceRect( iPoints[ iHoldingPointIndex ].iPos ).Contains( aPoint );
+ }
+
+// ----------------------------------------------------------------------------
+// IsLatestPoint
+// ----------------------------------------------------------------------------
+//
+TBool CGesture::IsLatestPoint( const TPoint& aPoint ) const
+ {
+ if ( iPoints.Count() > 0 )
+ {
+ return aPoint == CurrentPos();
+ }
+ return EFalse;
+ }
+// ----------------------------------------------------------------------------
+// IsLatestSecondaryPoint
+// ----------------------------------------------------------------------------
+//
+TBool CGesture::IsLatestSecondaryPoint( const TPoint& aPoint ) const
+ {
+ if ( iSecondaryPoints.Count() > 0 )
+ {
+ return aPoint == iSecondaryPoints[ iSecondaryPoints.Count() - 1 ].iPos;
+ }
+ return EFalse;
+ }
+
+// ----------------------------------------------------------------------------
+// StartHolding
+// ----------------------------------------------------------------------------
+//
+void CGesture::StartHolding()
+ {
+ iHoldingState = EHoldStarting;
+
+ // remove all points that were introduced after holding started
+ for ( TInt i = iPoints.Count() - 1; i > iHoldingPointIndex; i-- )
+ {
+ iPoints.Remove( i );
+ }
+ }
+
+// ----------------------------------------------------------------------------
+// SetHoldingPoint
+// ----------------------------------------------------------------------------
+//
+void CGesture::SetHoldingPoint()
+ {
+ iHoldingPointIndex = iPoints.Count() - 1;
+ }
+
+// ----------------------------------------------------------------------------
+// ContinueHolding
+// ----------------------------------------------------------------------------
+//
+void CGesture::ContinueHolding()
+ {
+ iHoldingState = EHolding;
+ }
+
+// ----------------------------------------------------------------------------
+// SetSingleTouchActive
+// ----------------------------------------------------------------------------
+//
+void CGesture::SetSingleTouchActive()
+ {
+ __ASSERT_DEBUG( ENotActive == iState, Panic( EGesturePanicIllegalLogic ) );
+ iState = ESingleTouchActive;
+ }
+// ----------------------------------------------------------------------------
+// SetMultiTouchActive
+// ----------------------------------------------------------------------------
+//
+void CGesture::SetMultiTouchActive()
+ {
+ iState = EMultiTouchActive;
+ iIsMultiTouched = ETrue;
+ }
+// ----------------------------------------------------------------------------
+// SetSingleTouchReleased
+// ----------------------------------------------------------------------------
+//
+void CGesture::SetSingleTouchReleased()
+ {
+ // IsMovementStopped expects corresponding SetComplete to be called before SetRelease
+ __ASSERT_DEBUG( ESingleTouchComplete == iState, Panic( EGesturePanicIllegalLogic ) );
+ iState = ESingleTouchReleased;
+ iIsMultiTouched = EFalse;
+ }
+// ----------------------------------------------------------------------------
+// SetMultiTouchReleased
+// ----------------------------------------------------------------------------
+//
+void CGesture::SetMultiTouchReleased()
+ {
+ // IsMovementStopped expects corresponding SetComplete to be called before SetRelease
+ __ASSERT_DEBUG( EMultiTouchComplete == iState, Panic( EGesturePanicIllegalLogic ) );
+ iState = EMultiTouchReleased;
+ }
+
+/**
+ * @return elapsed time between aStartTime and aEndTime
+ */
+inline TTimeIntervalMicroSeconds32 Elapsed( const TTime& aStartTime,
+ const TTime& aEndTime )
+ {
+ return aEndTime.MicroSecondsFrom( aStartTime ).Int64();
+ }
+
+// ----------------------------------------------------------------------------
+// SetSingleTouchComplete
+// ----------------------------------------------------------------------------
+//
+void CGesture::SetSingleTouchComplete()
+ {
+ __ASSERT_DEBUG( iPoints.Count() > 0, Panic( EGesturePanicIllegalLogic ) );
+ iState = ESingleTouchComplete;
+ iCompletionTime = CurrentTime();
+ }
+
+// ----------------------------------------------------------------------------
+// SetMultiTouchComplete
+// ----------------------------------------------------------------------------
+//
+void CGesture::SetMultiTouchComplete()
+ {
+ __ASSERT_DEBUG( iSecondaryPoints.Count() > 0, Panic( EGesturePanicIllegalLogic ) );
+ iState = EMultiTouchComplete;
+ }
+
+// ----------------------------------------------------------------------------
+// SetCancelled
+// ----------------------------------------------------------------------------
+//
+void CGesture::SetCancelled()
+ {
+ iState = ECancelled;
+ }
+
+// ----------------------------------------------------------------------------
+// SetDoubleTap
+// ----------------------------------------------------------------------------
+//
+void CGesture::SetDoubleTap()
+ {
+ iIsDoubleTap = ETrue;
+ }
+
+// ----------------------------------------------------------------------------
+// IsTap
+// ----------------------------------------------------------------------------
+//
+TBool CGesture::IsTap() const
+ {
+ if(iIsMultiTouched)
+ {
+ return EFalse;
+ }
+ return CodeFromPoints( iPoints, EAxisBoth ) == EGestureTap;
+ }
+
+// ----------------------------------------------------------------------------
+// IsPinch
+// ----------------------------------------------------------------------------
+//
+TBool CGesture::IsPinch()
+ {
+ if (iPinchStartDistance == -1 )
+ {
+ iPinchStartDistance = TGestureRecogniser().Length( iPoints[0].iPos, iSecondaryPoints[0].iPos ) ;
+ }
+ // if there is a pinch detected in the last attempt then update the start distance.
+ // henceforth this new distance is used as reference for calculating the pinch.
+
+ if( iPinchDetected )
+ {
+ iPinchStartDistance = iPinchEndDistance;
+ }
+ iPinchDetected = MultiTouchCode( iPoints, iSecondaryPoints, iPinchStartDistance,IsHighPinchTolerance()) == EGesturePinch;
+ if( iPinchDetected )
+ {
+ // This end distance is updated the first time the pinch is detected.
+ // This is done the save the value of pinch end distnce for further refernce to
+ // update the pinch start distance next time any pointer position changes.
+ iPinchEndDistance = TGestureRecogniser().Length(
+ LastPoint(iPoints).iPos,LastPoint(iSecondaryPoints).iPos );
+ iZoomState = iPinchEndDistance > iPinchStartDistance ? EZoomOut : EZoomIn;
+ }
+ return iPinchDetected;
+ }
+
+/**
+ * Translates a non-holding code into a holding code
+ * @param aCode original gesture code
+ * @return a gesture code with hold flag applied
+ */
+inline TGestureCode Hold( TGestureCode aCode )
+ {
+ if ( aCode != EGestureStart &&
+ aCode != EGestureDrag &&
+ aCode != EGestureReleased &&
+ aCode != EGestureUnknown )
+ {
+ return static_cast< TGestureCode >( aCode | EFlagHold );
+ }
+ return aCode;
+ }
+
+// ----------------------------------------------------------------------------
+// Code
+// ----------------------------------------------------------------------------
+//
+TGestureCode CGesture::Code( TAxis aRelevantAxis ) const
+ {
+ switch ( iState )
+ {
+ case ESingleTouchActive:
+ // "start" event if only first point received
+ // need to check that not holding, in case user pressed stylus
+ // down, and activated holding without moving the stylus
+ if ( iPoints.Count() == 1 && !IsHolding() )
+ {
+ return EGestureStart;
+ }
+ // "drag" event if holding not started or holding started earlier
+ else if ( iHoldingState != EHoldStarting )
+ {
+ // select the correct filter based on aRelevantAxis
+ // these filter_ objects are array decorators that will eliminate either
+ // x, y or neither coordinate of each point
+ TXAxisPointArray filterY( iPoints );
+ TYAxisPointArray filterX( iPoints );
+ TPointArray filterNone( iPoints );
+ TPointArray& filter =
+ aRelevantAxis == MGestureEvent::EAxisHorizontal ? static_cast< TPointArray& >( filterY ) :
+ aRelevantAxis == MGestureEvent::EAxisVertical ? static_cast< TPointArray& >( filterX ) :
+ /* otherwise EAxisBoth */ filterNone;
+
+ return TGestureRecogniser().ValidateDrag( filter, aRelevantAxis );
+ }
+ // holding was just started
+ else
+ {
+ return Hold( CodeFromPoints( iPoints, aRelevantAxis ) );
+ }
+
+ case EMultiTouchActive:
+ // Only if there are some points in secondary array
+ if ( iSecondaryPoints.Count() == 1 && iPoints.Count() == 1 )
+ {
+ return EGestureMultiTouchStart;
+ }
+ else
+ {
+ return MultiTouchCode( iPoints, iSecondaryPoints, iPinchStartDistance,IsHighPinchTolerance() );
+ }
+
+ case ESingleTouchComplete:
+ {
+ if ( iIsDoubleTap )
+ {
+ return EGestureDoubleTap;
+ }
+
+ // If there was a mulitouch within the last gesture then ignore the tap
+ TGestureCode gestureCode = CodeFromPoints( iPoints, aRelevantAxis );
+ if( gestureCode == EGestureTap && iIsMultiTouched)
+ {
+ return EGestureUnknown;
+ }
+ return gestureCode;
+ }
+ case EMultiTouchComplete:
+ return MultiTouchCode( iPoints, iSecondaryPoints, iPinchStartDistance,IsHighPinchTolerance());
+
+ case ESingleTouchReleased:
+ return EGestureReleased;
+ case EMultiTouchReleased:
+ return EGestureMultiTouchReleased;
+
+ case ECancelled: // fallthrough
+ case ENotActive:
+ default:
+ return EGestureUnknown;
+ }
+ }
+
+// ----------------------------------------------------------------------------
+// IsHolding
+// ----------------------------------------------------------------------------
+//
+TBool CGesture::IsHolding() const
+ {
+ return iHoldingState >= EHoldStarting;
+ }
+
+// ----------------------------------------------------------------------------
+// StartPos
+// ----------------------------------------------------------------------------
+//
+TPoint CGesture::StartPos() const
+ {
+ // at least one point will be in the array during callback (pointer down pos)
+ return iPoints[ 0 ].iPos;
+ }
+
+// ----------------------------------------------------------------------------
+// CurrentPos
+// ----------------------------------------------------------------------------
+//
+TPoint CGesture::CurrentPos() const
+ {
+ // at least on point will be in the array during callback (pointer down pos)
+ return iPoints[ iPoints.Count() - 1 ].iPos;
+ }
+
+// ----------------------------------------------------------------------------
+// IsMovementStopped
+// ----------------------------------------------------------------------------
+//
+inline TBool CGesture::IsMovementStopped() const
+ {
+ // iCompletionTime is only only valid if client has called SetComplete
+ if ( iState >= ESingleTouchComplete )
+ {
+ return Elapsed( NthLastEntry( 1 ).iTime, iCompletionTime ).Int() > KSpeedStopTime;
+ }
+ return EFalse;
+ }
+
+namespace
+ {
+ const TInt KFloatingPointAccuracy = 0.000001;
+
+ /** @return percentage (0.0-1.0) how far aPos is from aEdge1 towards aEdge2 */
+ inline TReal32 Proportion( TReal32 aPos, TReal32 aEdge1, TReal32 aEdge2 )
+ {
+ if ( Abs( aEdge2 - aEdge1 ) > KFloatingPointAccuracy )
+ {
+ return ( aPos - aEdge1 ) / ( aEdge2 - aEdge1 );
+ }
+ return 0; // avoid division by zero
+ }
+
+ /** Edges (pixels) at which speed should be -100% or 100% */
+ NONSHARABLE_STRUCT( TEdges )
+ {
+ TReal32 iMin;
+ TReal32 iMax;
+ };
+
+ /**
+ * scale which allows different (coordinate -> percentage) mapping
+ * between -100% to 0% and 0 and 100%
+ */
+ NONSHARABLE_STRUCT( TScale )
+ {
+ TScale( TInt aZero, const TEdges& aEdges )
+ : iMin( aEdges.iMin ), iZero( aZero ), iMax( aEdges.iMax )
+ {
+ }
+
+ /** @return aPos as a percentage between -100% and 100% in aScale */
+ TReal32 Percent( TReal32 aPos ) const;
+
+ /// coordinate where speed is -100%
+ TReal32 iMin;
+ /// coordinate where speed is 0%
+ TReal32 iZero;
+ /// coordinate where speed is 100%
+ TReal32 iMax;
+ };
+
+ /** @convert aPos into a percentage between -100% and 100% in aScale */
+ TReal32 TScale::Percent( TReal32 aPos ) const
+ {
+ TReal32 percent;
+ if ( aPos < iZero )
+ {
+ // return negative percentages on the lower side of zero point
+ percent = -1 * Proportion( aPos, iZero, iMin );
+ }
+ else
+ {
+ percent = Proportion( aPos, iZero, iMax );
+ }
+ // constrain between -100% and 100%
+ return Min( Max( percent, -1.0F ), 1.0F );
+ }
+
+ /** Scale in x and y dimensions */
+ NONSHARABLE_STRUCT( TScale2D )
+ {
+ TRealPoint Percent( const TPoint& aPos ) const
+ {
+ return TRealPoint( iX.Percent( aPos.iX ),
+ iY.Percent( aPos.iY ) );
+ }
+
+ TScale iX;
+ TScale iY;
+ };
+
+ enum TDirection { ESmaller, ELarger };
+
+ /** @return the direction of pos compared to the previous pos */
+ inline TDirection Direction( TInt aPos, TInt aPreviousPos )
+ {
+ return aPos < aPreviousPos ? ESmaller : ELarger;
+ }
+
+ /** Direction in x and y dimensions */
+ NONSHARABLE_STRUCT( TDirection2D )
+ {
+ TDirection iX;
+ TDirection iY;
+ };
+
+ /** Return the direction (up/down) of signal at aIndex */
+ inline TDirection2D Direction( TInt aIndex, const RArray< TPointEntry >& aPoints )
+ {
+ const TPoint& pos = aPoints[ aIndex ].iPos;
+ const TPoint& prevPos = aPoints[ aIndex - 1 ].iPos;
+ TDirection2D dir = { Direction( pos.iX, prevPos.iX ),
+ Direction( pos.iY, prevPos.iY ) };
+ return dir;
+ }
+ /**
+ * @return a position in the aLow and aHigh, so that it aProportion of
+ * of length is above the pos
+ */
+ TReal32 ProportionalLength( TReal32 aLow, TReal32 aHigh, TReal32 aProportion )
+ {
+ return ( aHigh - aLow ) * aProportion / ( 1 + aProportion );
+ }
+
+ /**
+ * @return aVariableEdge scaled to new position, when the other edge changes
+ * from aOldEdge to aNewEdge, so that aOrigin maintains the *same relative
+ * position* between aVariableEdge and the other edge
+ */
+ inline TReal32 ScaledEdge( TReal32 aOrigin, TReal32 aVariableEdge,
+ TReal32 aOldEdge, TReal aNewEdge )
+ {
+ TReal32 proportion = Proportion( aOrigin, aVariableEdge, aOldEdge );
+ return ( proportion * aNewEdge - aOrigin ) / ( proportion - 1 );
+ }
+
+ TScale Rescale( TReal32 aPos, TDirection aDir, TDirection aPrevDir,
+ const TScale& aPrevScale, const TEdges& aEdges )
+ {
+ TScale scale( aPrevScale );
+ if ( aPrevDir != aDir )
+ {
+ // the code duplication is accepted here, since it is difficult to factor out
+ // while maintaining the understandability of this anyway complex algorithm
+ if ( aDir == ESmaller )
+ {
+ scale.iMin = aEdges.iMin;
+ if ( aPrevScale.iZero < aPos )
+ {
+ TReal32 proportionAboveZero = Proportion( aPos, aPrevScale.iZero, aPrevScale.iMax );
+ scale.iZero = aPos - ProportionalLength( aEdges.iMin, aPos, proportionAboveZero );
+ }
+ else
+ {
+ // adjust zero pos so that proportion between aPos, Min, and Zero pos
+ // stay the same (Min will move to 0, aPos stays the same)
+ scale.iZero = ScaledEdge( aPos, aPrevScale.iZero,
+ aPrevScale.iMin, aEdges.iMin );
+ }
+ // adjust the upper edge to take into account the movement of zero pos
+ scale.iMax = ScaledEdge( aPos, aPrevScale.iMax,
+ aPrevScale.iZero, scale.iZero );
+ }
+ else // ELarger
+ {
+ scale.iMax = aEdges.iMax;
+ if ( aPos < aPrevScale.iZero )
+ {
+ TReal32 proportionBelowZero = Proportion( aPos, aPrevScale.iZero, aPrevScale.iMin );
+ scale.iZero = aPos + ProportionalLength( aPos, aEdges.iMax, proportionBelowZero );
+ }
+ else
+ {
+ // adjust zero pos so that proportion between aPos, Max, and Zero pos
+ // stay the same (Max will move edge, aPos stays the same)
+ scale.iZero = ScaledEdge( aPos, aPrevScale.iZero,
+ aPrevScale.iMax, aEdges.iMax );
+ }
+ // adjust the lower edge to take into account the movement of zero pos
+ scale.iMin = ScaledEdge( aPos, aPrevScale.iMin,
+ aPrevScale.iZero, scale.iZero );
+ }
+ }
+ return scale;
+ }
+
+ /** Edges in x and y dimensions */
+ NONSHARABLE_STRUCT( TEdges2D )
+ {
+ TEdges iX;
+ TEdges iY;
+ };
+
+ /**
+ * @param aEdges edges of the area in which gesture points are accepted
+ * @return the scale of latest point in the list of points
+ */
+ TScale2D Scale( const RArray< TPointEntry >& aPoints, const TEdges2D& aEdges )
+ {
+ TScale2D scale = { TScale( aPoints[0].iPos.iX, aEdges.iX ),
+ TScale( aPoints[0].iPos.iY, aEdges.iY ) };
+ TInt count = aPoints.Count();
+ if ( count > 1 )
+ {
+ // iterate the whole point list to arrive to the current scale
+ TDirection2D dir( Direction( 1, aPoints ) );
+ for ( TInt i = 1; i < count; i++ )
+ {
+ // get direction at i
+ TDirection2D newDir( Direction( i, aPoints ) );
+ // get new scale at i
+ scale.iX = Rescale( aPoints[i - 1].iPos.iX, newDir.iX, dir.iX, scale.iX, aEdges.iX );
+ scale.iY = Rescale( aPoints[i - 1].iPos.iY, newDir.iY, dir.iY, scale.iY, aEdges.iY );
+ dir = newDir;
+ }
+ }
+ return scale;
+ }
+ } // unnamed namespace
+
+TRealPoint CGesture::SpeedPercent( const TRect& aEdges ) const
+ {
+ // x and y coordinates are easier to handle separately, extract from TRect:
+ // ((iMinX, iMinY), (iMaxX, iMaxY)) -> ((iMinX, iMaxX), (iMinY, iMaxY))
+ TEdges2D edges = { { aEdges.iTl.iX, aEdges.iBr.iX },
+ { aEdges.iTl.iY, aEdges.iBr.iY } };
+ // work out the current scale (coordinate -> percentage mapping) from
+ // the history of points (i.e., points of current gesture). Then
+ // calculate the percentage of the current position.
+ return Scale( iPoints, edges ).Percent( CurrentPos() );
+ }
+
+// ----------------------------------------------------------------------------
+// Speed
+// ----------------------------------------------------------------------------
+//
+TRealPoint CGesture::Speed() const
+ {
+ const TReal32 KMicroSecondsInSecond = 1000000;
+
+ // Speed is only evaluated at the end of the swipe
+ // if user stops at the end of the swipe before lifting stylus,
+ // speed is zero. If time is zero, return 0 speed (infinite does
+ // not make sense either). Will need to consider also earlier points
+ // and their times or start time, if this zero-speed behavior is a problem
+ TRealPoint speed;
+ TReal32 time = static_cast<TReal32>( TimeFromPreviousPoint().Int() )
+ / KMicroSecondsInSecond;
+ if ( !IsMovementStopped() && time > 0 )
+ {
+ TPoint distance = CurrentPos() - PreviousPos();
+ speed.iX = static_cast<TReal32>( distance.iX ) / time;
+ speed.iY = static_cast<TReal32>( distance.iY ) / time;
+ }
+ return speed;
+ }
+
+// ----------------------------------------------------------------------------
+// Distance
+// ----------------------------------------------------------------------------
+//
+TPoint CGesture::Distance() const
+ {
+ return CurrentPos() - StartPos();
+ }
+
+// ----------------------------------------------------------------------------
+// Visual
+// ----------------------------------------------------------------------------
+//
+CAlfVisual* CGesture::Visual() const
+ {
+ return iVisual;
+ }
+
+// ----------------------------------------------------------------------------
+// TimeFromPreviousPoint
+// ----------------------------------------------------------------------------
+//
+inline TTimeIntervalMicroSeconds32 CGesture::TimeFromPreviousPoint() const
+ {
+ const TInt KLatestEntryOffset = 1;
+ return Elapsed( PreviousEntry().iTime, NthLastEntry( KLatestEntryOffset ).iTime );
+ }
+
+// ----------------------------------------------------------------------------
+// return nth point from the end of the points array
+// ----------------------------------------------------------------------------
+//
+inline const TPointEntry& CGesture::NthLastEntry( TInt aOffset ) const
+ {
+ return iPoints[ Max( iPoints.Count() - aOffset, 0 ) ];
+ }
+
+// ----------------------------------------------------------------------------
+// PreviousEntry
+// ----------------------------------------------------------------------------
+//
+inline const TPointEntry& CGesture::PreviousEntry() const
+ {
+ return NthLastEntry( KPreviousPointOffset );
+ }
+
+// ----------------------------------------------------------------------------
+// PreviousPos
+// ----------------------------------------------------------------------------
+//
+inline TPoint CGesture::PreviousPos() const
+ {
+ return PreviousEntry().iPos;
+ }
+
+// ----------------------------------------------------------------------------
+// PinchPercent
+// ----------------------------------------------------------------------------
+//
+TInt CGesture::PinchPercent() const
+ {
+ return (iPinchEndDistance*100/iPinchStartDistance);
+ }
+
+// ----------------------------------------------------------------------------
+// PinchCentrePoint
+// ----------------------------------------------------------------------------
+//
+TPoint CGesture::PinchCentrePoint() const
+ {
+ if( iPoints.Count() <= 0 || iSecondaryPoints.Count() <= 0 )
+ {
+ return TPoint(0,0);
+ }
+ TInt greaterX = iPoints[0].iPos.iX > iSecondaryPoints[0].iPos.iX ? iPoints[0].iPos.iX : iSecondaryPoints[0].iPos.iX;
+ TInt greaterY = iPoints[0].iPos.iY > iSecondaryPoints[0].iPos.iY ? iPoints[0].iPos.iY : iSecondaryPoints[0].iPos.iY;
+ return TPoint( (Abs(iPoints[0].iPos.iX - iSecondaryPoints[0].iPos.iX)/2 + greaterX), (Abs(iPoints[0].iPos.iY - iSecondaryPoints[0].iPos.iY)/2 + greaterY));
+ }
+
+// end of file
+