/// <summary>
/// C-tor.
/// </summary>
/// <param name="strokes">strokes to hit-test</param>
/// <param name="percentageWithinLasso">a hit-testing parameter that defines the minimal
/// percent of nodes of a stroke to be inside the lasso to consider the stroke hit</param>
internal IncrementalLassoHitTester(StrokeCollection strokes, int percentageWithinLasso)
: base(strokes)
{
System.Diagnostics.Debug.Assert((percentageWithinLasso >= 0) && (percentageWithinLasso <= 100));
_lasso = new SingleLoopLasso();
_percentIntersect = percentageWithinLasso;
}
/// <summary>
/// Erases all ink inside a lasso
/// </summary>
/// <param name="lassoPoints">lasso to erase within</param>
public void Erase(IEnumerable <Point> lassoPoints)
{
// Check the input parameters
if (lassoPoints == null)
{
throw new System.ArgumentNullException("lassoPoints");
}
int length = IEnumerablePointHelper.GetCount(lassoPoints);
if (length == 0)
{
throw new ArgumentException(SR.Get(SRID.EmptyArray));
}
if (length < 3)
{
return;
}
Lasso lasso = new SingleLoopLasso();
lasso.AddPoints(lassoPoints);
for (int i = 0; i < this.Count; i++)
{
Stroke stroke = this[i];
StrokeCollection eraseResult = stroke.Erase(stroke.HitTest(lasso));
UpdateStrokeCollection(stroke, eraseResult, ref i);
}
}
/// <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>
/// Erase with lasso points.
/// </summary>
/// <param name="lassoPoints">Lasso points to erase with</param>
/// <returns>The after-erasing strokes</returns>
public StrokeCollection GetEraseResult(IEnumerable <Point> lassoPoints)
{
// Check the input parameters
if (lassoPoints == null)
{
throw new System.ArgumentNullException("lassoPoints");
}
if (IEnumerablePointHelper.GetCount(lassoPoints) == 0)
{
throw new ArgumentException(SR.Get(SRID.EmptyArray));
}
Lasso lasso = new SingleLoopLasso();
lasso.AddPoints(lassoPoints);
return(this.Erase(this.HitTest(lasso)));
}
/// <summary>
/// Clips out all ink outside a given lasso
/// </summary>
/// <param name="lassoPoints">lasso</param>
public void Clip(IEnumerable <Point> lassoPoints)
{
// Check the input parameters
if (lassoPoints == null)
{
throw new System.ArgumentNullException("lassoPoints");
}
int length = IEnumerablePointHelper.GetCount(lassoPoints);
if (length == 0)
{
throw new ArgumentException(SR.Get(SRID.EmptyArray));
}
if (length < 3)
{
//
// if you're clipping with a point or a line with
// two points, it doesn't matter where the line is or if it
// intersects any of the strokes, the point or line has no region
// so technically everything in the strokecollection
// should be removed
//
this.Clear(); //raises the appropriate events
return;
}
Lasso lasso = new SingleLoopLasso();
lasso.AddPoints(lassoPoints);
for (int i = 0; i < this.Count; i++)
{
Stroke stroke = this[i];
StrokeCollection clipResult = stroke.Clip(stroke.HitTest(lasso));
UpdateStrokeCollection(stroke, clipResult, ref i);
}
}
/// <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);
}
