/// <summary>
/// Recognize gesture from the recorded data
/// </summary>
/// <returns>Returns MouseGesture or MouseGesture.Unknown if no gesture is recognized.</returns>
/// <remarks>
/// Funtion counts the number of unknown segments before the gestures,
/// the number of segments in the gestures and the number of unknown segments
/// after the gestures. These counts are keystone for the gesture recognition.
/// </remarks>
private MouseGesture RecognizeGesture()
{
int index = 0;
int unknownSegmentsBefore = CountMouseMoveSegments(ref index, MouseMoveSegment.SegmentDirection.Unknown);
MouseMoveSegment.SegmentDirection firstSegmentDirection;
int firstGestureLenght = CountMouseMoveSegments(ref index, out firstSegmentDirection);
int unknownSegmentsMiddle = CountMouseMoveSegments(ref index, MouseMoveSegment.SegmentDirection.Unknown);
MouseMoveSegment.SegmentDirection secondSegmentDirection = MouseMoveSegment.SegmentDirection.Unknown;
int secondGestureLength = 0;
int unknownSegmentAfter = 0;
//if complex gesture are enabled count segments for the second gesture
if (enableComplexGestures)
{
secondGestureLength = CountMouseMoveSegments(ref index, out secondSegmentDirection);
unknownSegmentAfter = CountMouseMoveSegments(ref index, MouseMoveSegment.SegmentDirection.Unknown);
}
//if there are some segments left, the recorded data does not contain valid mouse gesture
MouseMoveSegment.SegmentDirection nextSegment;
if (CountMouseMoveSegments(ref index, out nextSegment) > 0)
{
return(MouseGesture.Unknown);
}
//recognize firs gesture
MouseGesture firstGesture =
RecognizeSimpleGesture(unknownSegmentsBefore, firstGestureLenght,
unknownSegmentsMiddle, firstSegmentDirection);
//if complex gesture are enabled continue with second gesture
MouseGesture secondGesture;
if ((enableComplexGestures) && (secondGestureLength > 0))
{
secondGesture = RecognizeSimpleGesture(unknownSegmentsMiddle, secondGestureLength,
unknownSegmentAfter, secondSegmentDirection);
return(RecognizeComplexGeasture(firstGesture, secondGesture));
}
else
{
return(firstGesture);
}
}
/// <summary>
/// Counts segments in row with SegmentDirection.
/// Counting started at the index of mouseMoveSegments array.
/// </summary>
/// <param name="index">
/// Index to start at. Index to start next search is passed to
/// this var.
/// </param>
/// <param name="segmentDirection">The direction of segments to count.</param>
/// <returns>Returns the number of segments with direction in the row.</returns>
public int CountMouseMoveSegments(ref int index, MouseMoveSegment.SegmentDirection segmentDirection)
{
int count = 0;
while (index < mouseMoveSegments.Count &&
mouseMoveSegments[index].Direction == segmentDirection)
{
index++;
count++;
}
return(count);
}
/// <summary>
/// Counts segments with the same direction in mouseMoveSegments.
/// Counting started at the index of mouseMoveSegments array and
/// the direction of segments is passed to the segmentDirection
/// </summary>
/// <param name="index">
/// Index to start at. Index to start next search is passed to
/// this var.
/// </param>
/// <param name="segmentDirection">
/// The direction of the segments is passed
/// to this var.
/// </param>
/// <returns>Returns the number of segments with the same direction in the row.</returns>
public int CountMouseMoveSegments(ref int index, out MouseMoveSegment.SegmentDirection segmentDirection)
{
int count = 0;
segmentDirection = MouseMoveSegment.SegmentDirection.Unknown;
if (index < mouseMoveSegments.Count)
{
segmentDirection = mouseMoveSegments[index].Direction;
}
else
{
return(0);
}
while (index < mouseMoveSegments.Count &&
mouseMoveSegments[index].Direction == segmentDirection)
{
index++;
count++;
}
return(count);
}
/// <summary>
/// Tries to recognize simple mouse gesture
/// </summary>
/// <param name="unknownBefore">The number of segments with SegmentDirection.Unknown before the gesture</param>
/// <param name="length">The number of segments of the gesture.</param>
/// <param name="unknownAfter">The number of segments with SegmentDirection.Unknown after the gesture</param>
/// <param name="direction">The direction of the gesture.</param>
/// <returns>Returns the simple gesture or MouseGesture.Unknown if no gesture is recognized.</returns>
protected MouseGesture RecognizeSimpleGesture(int unknownBefore, int length, int unknownAfter, MouseMoveSegment.SegmentDirection direction)
{
// max length of unknown segments before and after gesture
double lengthTolerance = length * maxUnknownSkipRatio;
// check unknown segments
if ((unknownBefore < lengthTolerance) && (unknownAfter < lengthTolerance))
{
//according to the direction of the segment choose simple MouseGesture
switch (direction)
{
case MouseMoveSegment.SegmentDirection.Up:
return(MouseGesture.Up);
case MouseMoveSegment.SegmentDirection.Right:
return(MouseGesture.Right);
case MouseMoveSegment.SegmentDirection.Down:
return(MouseGesture.Down);
case MouseMoveSegment.SegmentDirection.Left:
return(MouseGesture.Left);
}
}
return(MouseGesture.Unknown);
}
