/// <summary>
/// Check whether a certain percentage of the stroke is within the lasso
/// </summary>
/// <param name="lassoPoints"></param>
/// <param name="percentageWithinLasso"></param>
/// <returns></returns>
public bool HitTest(IEnumerable <Point> lassoPoints, int percentageWithinLasso)
{
if (lassoPoints == null)
{
throw new System.ArgumentNullException("lassoPoints");
}
if ((percentageWithinLasso < 0) || (percentageWithinLasso > 100))
{
throw new System.ArgumentOutOfRangeException("percentageWithinLasso");
}
if (percentageWithinLasso == 0)
{
return(true);
}
StrokeInfo strokeInfo = null;
try
{
strokeInfo = new StrokeInfo(this);
StylusPointCollection stylusPoints = strokeInfo.StylusPoints;
double target = strokeInfo.TotalWeight * percentageWithinLasso / 100.0f - PercentageTolerance;
Lasso lasso = new SingleLoopLasso();
lasso.AddPoints(lassoPoints);
for (int i = 0; i < stylusPoints.Count; i++)
{
if (true == lasso.Contains((Point)stylusPoints[i]))
{
target -= strokeInfo.GetPointWeight(i);
if (DoubleUtil.LessThan(target, 0f))
{
return(true);
}
}
}
return(false);
}
finally
{
if (strokeInfo != null)
{
//detach from event handlers, or else we leak.
strokeInfo.Detach();
}
}
}
/// <summary>
/// IHT's can get into a state where their StrokeInfo cache is too
/// out of sync with the StrokeCollection to incrementally update it.
/// When we detect this has happened, we just rebuild the entire cache.
/// </summary>
private void RebuildStrokeInfoCache()
{
List <StrokeInfo> newStrokeInfos = new List <StrokeInfo>(_strokes.Count);
foreach (Stroke stroke in _strokes)
{
bool found = false;
for (int x = 0; x < _strokeInfos.Count; x++)
{
StrokeInfo strokeInfo = _strokeInfos[x];
if (strokeInfo != null && stroke == strokeInfo.Stroke)
{
newStrokeInfos.Add(strokeInfo);
//just set to null instead of removing and shifting
//we're about to GC _strokeInfos
_strokeInfos[x] = null;
found = true;
break;
}
}
if (!found)
{
//we didn't find an existing strokeInfo
newStrokeInfos.Add(new StrokeInfo(stroke));
}
}
//detach the remaining strokeInfo's from their strokes
for (int x = 0; x < _strokeInfos.Count; x++)
{
StrokeInfo strokeInfo = _strokeInfos[x];
if (strokeInfo != null)
{
strokeInfo.Detach();
}
}
_strokeInfos = newStrokeInfos;
#if DEBUG
Debug.Assert(_strokeInfos.Count == _strokes.Count);
for (int x = 0; x < _strokeInfos.Count; x++)
{
Debug.Assert(_strokeInfos[x].Stroke == _strokes[x]);
}
#endif
}
/// <summary>
/// Check whether a certain percentage of the stroke is within the Rect passed in.
/// </summary>
/// <param name="bounds"></param>
/// <param name="percentageWithinBounds"></param>
/// <returns></returns>
public bool HitTest(Rect bounds, int percentageWithinBounds)
{
if ((percentageWithinBounds < 0) || (percentageWithinBounds > 100))
{
throw new System.ArgumentOutOfRangeException("percentageWithinBounds");
}
if (percentageWithinBounds == 0)
{
return(true);
}
StrokeInfo strokeInfo = null;
try
{
strokeInfo = new StrokeInfo(this);
StylusPointCollection stylusPoints = strokeInfo.StylusPoints;
double target = strokeInfo.TotalWeight * percentageWithinBounds / 100.0f - PercentageTolerance;
for (int i = 0; i < stylusPoints.Count; i++)
{
if (true == bounds.Contains((Point)stylusPoints[i]))
{
target -= strokeInfo.GetPointWeight(i);
if (DoubleUtil.LessThanOrClose(target, 0d))
{
return(true);
}
}
}
return(false);
}
finally
{
if (strokeInfo != null)
{
//detach from event handlers, or else we leak.
strokeInfo.Detach();
}
}
}
/// <summary>
/// Hit-testing with lasso
/// </summary>
/// <param name="lassoPoints">points making the lasso</param>
/// <param name="percentageWithinLasso">the margin value to tell whether a stroke
/// is in or outside of the rect</param>
/// <returns>collection of strokes found inside the rectangle</returns>
public StrokeCollection HitTest(IEnumerable <Point> lassoPoints, int percentageWithinLasso)
{
// Check the input parameters
if (lassoPoints == null)
{
throw new System.ArgumentNullException("lassoPoints");
}
if ((percentageWithinLasso < 0) || (percentageWithinLasso > 100))
{
throw new System.ArgumentOutOfRangeException("percentageWithinLasso");
}
if (IEnumerablePointHelper.GetCount(lassoPoints) < 3)
{
return(new StrokeCollection());
}
Lasso lasso = new SingleLoopLasso();
lasso.AddPoints(lassoPoints);
// Enumerate through the strokes and collect those captured by the lasso.
StrokeCollection lassoedStrokes = new StrokeCollection();
foreach (Stroke stroke in this)
{
if (percentageWithinLasso == 0)
{
lassoedStrokes.Add(stroke);
}
else
{
StrokeInfo strokeInfo = null;
try
{
strokeInfo = new StrokeInfo(stroke);
StylusPointCollection stylusPoints = strokeInfo.StylusPoints;
double target = strokeInfo.TotalWeight * percentageWithinLasso / 100.0f - Stroke.PercentageTolerance;
for (int i = 0; i < stylusPoints.Count; i++)
{
if (true == lasso.Contains((Point)stylusPoints[i]))
{
target -= strokeInfo.GetPointWeight(i);
if (DoubleUtil.LessThanOrClose(target, 0f))
{
lassoedStrokes.Add(stroke);
break;
}
}
}
}
finally
{
if (strokeInfo != null)
{
//detach from event handlers, or else we leak.
strokeInfo.Detach();
}
}
}
}
// Return the resulting collection
return(lassoedStrokes);
}
