/// <summary>
/// Hit-testing for stroke erase scenario.
/// </summary>
/// <param name="iterator">the stroke nodes to iterate</param>
/// <returns>true if the strokes intersect, false otherwise</returns>
internal bool HitTest(StrokeNodeIterator iterator)
{
System.Diagnostics.Debug.Assert(iterator != null);
if ((_erasingStrokeNodes == null) || (_erasingStrokeNodes.Count == 0))
{
return(false);
}
Rect inkSegmentBounds = Rect.Empty;
for (int i = 0; i < iterator.Count; i++)
{
StrokeNode inkStrokeNode = iterator[i];
Rect inkNodeBounds = inkStrokeNode.GetBounds();
inkSegmentBounds.Union(inkNodeBounds);
if (inkSegmentBounds.IntersectsWith(_bounds))
{
//
foreach (StrokeNode erasingStrokeNode in _erasingStrokeNodes)
{
if (inkSegmentBounds.IntersectsWith(erasingStrokeNode.GetBoundsConnected()) &&
erasingStrokeNode.HitTest(inkStrokeNode))
{
return(true);
}
}
}
}
return(false);
}
/// <summary>
/// Merge two crossings into one.
/// </summary>
/// <param name="crossing"></param>
/// <returns>Return true if these two crossings are actually overlapping and merged; false otherwise</returns>
public bool Merge(LassoCrossing crossing)
{
if (crossing.IsEmpty)
{
return(false);
}
if (FIndices.IsEmpty && !crossing.IsEmpty)
{
FIndices = crossing.FIndices;
StartNode = crossing.StartNode;
EndNode = crossing.EndNode;
return(true);
}
if (DoubleUtil.GreaterThanOrClose(crossing.FIndices.EndFIndex, FIndices.BeginFIndex) &&
DoubleUtil.GreaterThanOrClose(FIndices.EndFIndex, crossing.FIndices.BeginFIndex))
{
if (DoubleUtil.LessThan(crossing.FIndices.BeginFIndex, FIndices.BeginFIndex))
{
FIndices.BeginFIndex = crossing.FIndices.BeginFIndex;
StartNode = crossing.StartNode;
}
if (DoubleUtil.GreaterThan(crossing.FIndices.EndFIndex, FIndices.EndFIndex))
{
FIndices.EndFIndex = crossing.FIndices.EndFIndex;
EndNode = crossing.EndNode;
}
return(true);
}
return(false);
}
/// <summary>
/// Generates stroke nodes along a given path.
/// Drops any previously genererated nodes.
/// </summary>
/// <param name="path"></param>
internal void MoveTo(IEnumerable <Point> path)
{
System.Diagnostics.Debug.Assert((path != null) && (IEnumerablePointHelper.GetCount(path) != 0));
Point[] points = IEnumerablePointHelper.GetPointArray(path);
if (_erasingStrokeNodes == null)
{
_erasingStrokeNodes = new List <StrokeNode>(points.Length);
}
else
{
_erasingStrokeNodes.Clear();
}
_bounds = Rect.Empty;
_nodeIterator = _nodeIterator.GetIteratorForNextSegment(points.Length > 1 ? FilterPoints(points) : points);
for (int i = 0; i < _nodeIterator.Count; i++)
{
StrokeNode strokeNode = _nodeIterator[i];
_bounds.Union(strokeNode.GetBoundsConnected());
_erasingStrokeNodes.Add(strokeNode);
}
#if POINTS_FILTER_TRACE
_totalPointsAdded += path.Length;
System.Diagnostics.Debug.WriteLine(String.Format("Total Points added: {0} screened: {1} collinear screened: {2}", _totalPointsAdded, _totalPointsScreened, _collinearPointsScreened));
#endif
}
/// <summary>
/// Hit-testing for stroke erase scenario.
/// </summary>
/// <param name="iterator">the stroke nodes to iterate</param>
/// <returns>true if the strokes intersect, false otherwise</returns>
internal bool HitTest(StrokeNodeIterator iterator)
{
System.Diagnostics.Debug.Assert(iterator != null);
if ((_erasingStrokeNodes == null) || (_erasingStrokeNodes.Count == 0))
{
return(false);
}
Rect inkSegmentBounds = Rect.Empty;
for (int i = 0; i < iterator.Count; i++)
{
StrokeNode inkStrokeNode = iterator[i];
Rect inkNodeBounds = inkStrokeNode.GetBounds();
inkSegmentBounds.Union(inkNodeBounds);
if (inkSegmentBounds.IntersectsWith(_bounds))
{
for (var index = 0; index < _erasingStrokeNodes.Count; index++)
{
var erasingStrokeNodeBound = _erasingStrokeNodeBounds[index];
if (inkSegmentBounds.IntersectsWith(erasingStrokeNodeBound))
{
StrokeNode erasingStrokeNode = _erasingStrokeNodes[index];
if (erasingStrokeNode.HitTest(inkStrokeNode))
{
return(true);
}
}
}
}
}
return(false);
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="newFIndices"></param>
/// <param name="strokeNode"></param>
public LassoCrossing(StrokeFIndices newFIndices, StrokeNode strokeNode)
{
System.Diagnostics.Debug.Assert(!newFIndices.IsEmpty);
System.Diagnostics.Debug.Assert(strokeNode.IsValid);
FIndices = newFIndices;
StartNode = EndNode = strokeNode;
}
/// <summary>
/// This method tells whether the contour of a given stroke node
/// intersects with the contour of this node. The contours of both nodes
/// include their connecting quadrangles.
/// </summary>
/// <param name="hitNode"></param>
/// <returns></returns>
internal bool HitTest(StrokeNode hitNode)
{
if (!IsValid || !hitNode.IsValid)
{
return(false);
}
IEnumerable <ContourSegment> hittingContour = hitNode.GetContourSegments();
return(_operations.HitTest(_lastNode, _thisNode, ConnectingQuad, hittingContour));
}
/// <summary>
/// Finds out if a given node intersects with this one,
/// and returns findices of the intersection.
/// </summary>
/// <param name="hitNode"></param>
/// <returns></returns>
internal StrokeFIndices CutTest(StrokeNode hitNode)
{
if ((IsValid == false) || (hitNode.IsValid == false))
{
return(StrokeFIndices.Empty);
}
IEnumerable <ContourSegment> hittingContour = hitNode.GetContourSegments();
// If the node contours intersect, the result is a pair of findices
// this segment should be cut at to let the hitNode's contour through it.
StrokeFIndices cutAt = _operations.CutTest(_lastNode, _thisNode, ConnectingQuad, hittingContour);
return((_index == 0) ? cutAt : BindFIndices(cutAt));
}
/// <summary>
/// Helper function to find out whether a point is inside the lasso
/// </summary>
private bool SegmentWithinLasso(StrokeNode strokeNode, double fIndex)
{
bool currentSegmentWithinLasso;
if (DoubleUtil.AreClose(fIndex, StrokeFIndices.BeforeFirst))
{
// This should check against the very first stroke node
currentSegmentWithinLasso = this.Contains(strokeNode.GetPointAt(0f));
}
else if (DoubleUtil.AreClose(fIndex, StrokeFIndices.AfterLast))
{
// This should check against the last stroke node
currentSegmentWithinLasso = this.Contains(strokeNode.Position);
}
else
{
currentSegmentWithinLasso = this.Contains(strokeNode.GetPointAt(fIndex));
}
return(currentSegmentWithinLasso);
}
/// <summary>
/// GetPointsAtMiddleSegment
/// </summary>
internal void GetPointsAtMiddleSegment( StrokeNode previous,
double angleBetweenNodes,
List<Point> abPoints,
List<Point> dcPoints,
out bool missingIntersection
#if DEBUG_RENDERING_FEEDBACK
, DrawingContext debugDC, double feedbackSize, bool showFeedback
#endif
)
{
missingIntersection = false;
if (IsValid && previous.IsValid)
{
Quad quad1 = previous.ConnectingQuad;
if (!quad1.IsEmpty)
{
Quad quad2 = ConnectingQuad;
if (!quad2.IsEmpty)
{
if (IsEllipse)
{
Rect node1Bounds = _operations.GetNodeBounds(previous._lastNode);
Rect node2Bounds = _operations.GetNodeBounds(_lastNode);
Rect node3Bounds = _operations.GetNodeBounds(_thisNode);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(null, new Pen(Brushes.Pink, feedbackSize / 2), _lastNode.Position, node2Bounds.Width / 2, node2Bounds.Height / 2);
}
#endif
if (angleBetweenNodes == 0.0d || ((quad1.B == quad2.A) && (quad1.C == quad2.D)))
{
//quads connections are the same, just add them
abPoints.Add(quad1.B);
dcPoints.Add(quad1.C);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize, feedbackSize);
}
#endif
}
else if (angleBetweenNodes > 0.0)
{
//the stroke angled towards the AB side
//this part is easy
if (quad1.B == quad2.A)
{
abPoints.Add(quad1.B);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize, feedbackSize);
}
#endif
}
else
{
Point intersection = GetIntersection(quad1.A, quad1.B, quad2.A, quad2.B);
Rect union = Rect.Union(node1Bounds, node2Bounds);
union.Inflate(1.0, 1.0);
//make sure we're not off in space
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize * 1.5, feedbackSize * 1.5);
debugDC.DrawEllipse(Brushes.Red, null, quad2.A, feedbackSize, feedbackSize);
}
#endif
if (union.Contains(intersection))
{
abPoints.Add(intersection);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Orange, null, intersection, feedbackSize, feedbackSize);
}
#endif
}
else
{
//if we missed the intersection we'll need to close the stroke segment
//this work is done in StrokeRenderer
missingIntersection = true;
return; //we're done.
}
}
if (quad1.C == quad2.D)
{
dcPoints.Add(quad1.C);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize, feedbackSize);
}
#endif
}
else
{
//add instructions to arc from quad1.C to quad2.D in reverse order (since we walk this array backwards to render)
dcPoints.Add(quad1.C);
dcPoints.Add(new Point(node2Bounds.Width, node2Bounds.Height));
dcPoints.Add(StrokeRenderer.ArcToMarker);
dcPoints.Add(quad2.D);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Blue, null, quad2.D, feedbackSize, feedbackSize);
}
#endif
}
}
else
{
//the stroke angled towards the CD side
//this part is easy
if (quad1.C == quad2.D)
{
dcPoints.Add(quad1.C);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize, feedbackSize);
}
#endif
}
else
{
Point intersection = GetIntersection(quad1.D, quad1.C, quad2.D, quad2.C);
Rect union = Rect.Union(node1Bounds, node2Bounds);
union.Inflate(1.0, 1.0);
//make sure we're not off in space
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize * 1.5, feedbackSize * 1.5);
debugDC.DrawEllipse(Brushes.Blue, null, quad2.D, feedbackSize, feedbackSize);
}
#endif
if (union.Contains(intersection))
{
dcPoints.Add(intersection);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Orange, null, intersection, feedbackSize, feedbackSize);
}
#endif
}
else
{
//if we missed the intersection we'll need to close the stroke segment
//this work is done in StrokeRenderer
missingIntersection = true;
return; //we're done.
}
}
if (quad1.B == quad2.A)
{
abPoints.Add(quad1.B);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize, feedbackSize);
}
#endif
}
else
{
//we need to arc between quad1.B and quad2.A along node2
abPoints.Add(quad1.B);
abPoints.Add(StrokeRenderer.ArcToMarker);
abPoints.Add(new Point(node2Bounds.Width, node2Bounds.Height));
abPoints.Add(quad2.A);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Red, null, quad2.A, feedbackSize, feedbackSize);
}
#endif
}
}
}
else
{
//rectangle
int indexA = -1;
int indexB = -1;
int indexC = -1;
int indexD = -1;
Vector[] vertices = _operations.GetVertices();
double pressureFactor = _lastNode.PressureFactor;
for (int i = 0; i < vertices.Length; i++)
{
Point point = _lastNode.Position + (vertices[i % vertices.Length] * pressureFactor);
if (point == quad2.A)
{
indexA = i;
}
if (point == quad1.B)
{
indexB = i;
}
if (point == quad1.C)
{
indexC = i;
}
if (point == quad2.D)
{
indexD = i;
}
}
if (indexA == -1 || indexB == -1 || indexC == -1 || indexD == -1)
{
Debug.Assert(false, "Couldn't find all 4 indexes in StrokeNodeOperations.GetPointsAtMiddleSegment");
return;
}
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawRectangle(null, new Pen(Brushes.Pink, feedbackSize / 2), _operations.GetNodeBounds(_lastNode));
debugDC.DrawEllipse(Brushes.Red, null, quad2.A, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Blue, null, quad2.D, feedbackSize, feedbackSize);
}
#endif
Rect node3Rect = _operations.GetNodeBounds(_thisNode);
//take care of a-b first
if (indexA == indexB)
{
//quad connection is the same, just add it
if (!node3Rect.Contains(quad1.B))
{
abPoints.Add(quad1.B);
}
}
else if ((indexA == 0 && indexB == 3) || ((indexA != 3 || indexB != 0) && (indexA > indexB)))
{
if (!node3Rect.Contains(quad1.B))
{
abPoints.Add(quad1.B);
}
if (!node3Rect.Contains(quad2.A))
{
abPoints.Add(quad2.A);
}
}
else
{
Point intersection = GetIntersection(quad1.A, quad1.B, quad2.A, quad2.B);
Rect node12 = Rect.Union(_operations.GetNodeBounds(previous._lastNode), _operations.GetNodeBounds(_lastNode));
node12.Inflate(1.0, 1.0);
//make sure we're not off in space
if (node12.Contains(intersection))
{
abPoints.Add(intersection);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Orange, null, intersection, feedbackSize, feedbackSize * 1.5);
}
#endif
}
else
{
//if we missed the intersection we'll need to close the stroke segment
//this work is done in StrokeRenderer.
missingIntersection = true;
return; //we're done.
}
}
// now take care of c-d.
if (indexC == indexD)
{
//quad connection is the same, just add it
if (!node3Rect.Contains(quad1.C))
{
dcPoints.Add(quad1.C);
}
}
else if ((indexC == 0 && indexD == 3) || ((indexC != 3 || indexD != 0) && (indexC > indexD)))
{
if (!node3Rect.Contains(quad1.C))
{
dcPoints.Add(quad1.C);
}
if (!node3Rect.Contains(quad2.D))
{
dcPoints.Add(quad2.D);
}
}
else
{
Point intersection = GetIntersection(quad1.D, quad1.C, quad2.D, quad2.C);
Rect node12 = Rect.Union(_operations.GetNodeBounds(previous._lastNode), _operations.GetNodeBounds(_lastNode));
node12.Inflate(1.0, 1.0);
//make sure we're not off in space
if (node12.Contains(intersection))
{
dcPoints.Add(intersection);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Orange, null, intersection, feedbackSize, feedbackSize * 1.5);
}
#endif
}
else
{
//if we missed the intersection we'll need to close the stroke segment
//this work is done in StrokeRenderer.
missingIntersection = true;
return; //we're done.
}
}
}
}
}
}
}
/// <summary>
/// Hit-testing for point erase.
/// </summary>
/// <param name="iterator"></param>
/// <param name="intersections"></param>
/// <returns></returns>
internal bool EraseTest(StrokeNodeIterator iterator, List <StrokeIntersection> intersections)
{
System.Diagnostics.Debug.Assert(iterator != null);
System.Diagnostics.Debug.Assert(intersections != null);
intersections.Clear();
List <StrokeFIndices> eraseAt = new List <StrokeFIndices>();
if ((_erasingStrokeNodes == null) || (_erasingStrokeNodes.Count == 0))
{
return(false);
}
Rect inkSegmentBounds = Rect.Empty;
for (int x = 0; x < iterator.Count; x++)
{
StrokeNode inkStrokeNode = iterator[x];
Rect inkNodeBounds = inkStrokeNode.GetBounds();
inkSegmentBounds.Union(inkNodeBounds);
if (inkSegmentBounds.IntersectsWith(_bounds))
{
//
int index = eraseAt.Count;
foreach (StrokeNode erasingStrokeNode in _erasingStrokeNodes)
{
if (false == inkSegmentBounds.IntersectsWith(erasingStrokeNode.GetBoundsConnected()))
{
continue;
}
StrokeFIndices fragment = inkStrokeNode.CutTest(erasingStrokeNode);
if (fragment.IsEmpty)
{
continue;
}
// Merge it with the other results for this ink segment
bool inserted = false;
for (int i = index; i < eraseAt.Count; i++)
{
StrokeFIndices lastFragment = eraseAt[i];
if (fragment.BeginFIndex < lastFragment.EndFIndex)
{
// If the fragments overlap, merge them
if (fragment.EndFIndex > lastFragment.BeginFIndex)
{
fragment = new StrokeFIndices(
Math.Min(lastFragment.BeginFIndex, fragment.BeginFIndex),
Math.Max(lastFragment.EndFIndex, fragment.EndFIndex));
// If the fragment doesn't go beyond lastFragment, break
if ((fragment.EndFIndex <= lastFragment.EndFIndex) || ((i + 1) == eraseAt.Count))
{
inserted = true;
eraseAt[i] = fragment;
break;
}
else
{
eraseAt.RemoveAt(i);
i--;
}
}
// insert otherwise
else
{
eraseAt.Insert(i, fragment);
inserted = true;
break;
}
}
}
// If not merged nor inserted, add it to the end of the list
if (false == inserted)
{
eraseAt.Add(fragment);
}
// Break out if the entire ink segment is hit - {BeforeFirst, AfterLast}
if (eraseAt[eraseAt.Count - 1].IsFull)
{
break;
}
}
// Merge inter-segment overlapping fragments
if ((index > 0) && (index < eraseAt.Count))
{
StrokeFIndices lastFragment = eraseAt[index - 1];
if (DoubleUtil.AreClose(lastFragment.EndFIndex, StrokeFIndices.AfterLast))
{
if (DoubleUtil.AreClose(eraseAt[index].BeginFIndex, StrokeFIndices.BeforeFirst))
{
lastFragment.EndFIndex = eraseAt[index].EndFIndex;
eraseAt[index - 1] = lastFragment;
eraseAt.RemoveAt(index);
}
else
{
lastFragment.EndFIndex = inkStrokeNode.Index;
eraseAt[index - 1] = lastFragment;
}
}
}
}
// Start next ink segment
inkSegmentBounds = inkNodeBounds;
}
if (eraseAt.Count != 0)
{
foreach (StrokeFIndices segment in eraseAt)
{
intersections.Add(new StrokeIntersection(segment.BeginFIndex, StrokeFIndices.AfterLast,
StrokeFIndices.BeforeFirst, segment.EndFIndex));
}
}
return(eraseAt.Count != 0);
}
internal static void CalcGeometryAndBounds(StrokeNodeIterator iterator,
DrawingAttributes drawingAttributes,
#if DEBUG_RENDERING_FEEDBACK
DrawingContext debugDC,
double feedbackSize,
bool showFeedback,
#endif
bool calculateBounds,
out Geometry geometry,
out Rect bounds)
{
Debug.Assert(iterator != null && drawingAttributes != null);
//we can use our new algorithm for identity only.
Matrix stylusTipTransform = drawingAttributes.StylusTipTransform;
if (stylusTipTransform != Matrix.Identity && stylusTipTransform._type != MatrixTypes.TRANSFORM_IS_SCALING)
{
//second best optimization
CalcGeometryAndBoundsWithTransform(iterator, drawingAttributes, stylusTipTransform._type, calculateBounds, out geometry, out bounds);
}
else
{
StreamGeometry streamGeometry = new StreamGeometry();
streamGeometry.FillRule = FillRule.Nonzero;
StreamGeometryContext context = streamGeometry.Open();
geometry = streamGeometry;
Rect empty = Rect.Empty;
bounds = empty;
try
{
//
// We keep track of three StrokeNodes as we iterate across
// the Stroke. Since these are structs, the default ctor will
// be called and .IsValid will be false until we initialize them
//
StrokeNode emptyStrokeNode = new StrokeNode();
StrokeNode prevPrevStrokeNode = new StrokeNode();
StrokeNode prevStrokeNode = new StrokeNode();
StrokeNode strokeNode = new StrokeNode();
Rect prevPrevStrokeNodeBounds = empty;
Rect prevStrokeNodeBounds = empty;
Rect strokeNodeBounds = empty;
//percentIntersect is a function of drawingAttributes height / width
double percentIntersect = 95d;
double maxExtent = Math.Max(drawingAttributes.Height, drawingAttributes.Width);
percentIntersect += Math.Min(4.99999d, ((maxExtent / 20d) * 5d));
double prevAngle = double.MinValue;
bool isStartOfSegment = true;
bool isEllipse = drawingAttributes.StylusTip == StylusTip.Ellipse;
bool ignorePressure = drawingAttributes.IgnorePressure;
//
// Two List<Point>'s that get reused for adding figures
// to the streamgeometry.
//
List<Point> pathFigureABSide = new List<Point>();//don't prealloc. It causes Gen2 collections to rise and doesn't help execution time
List<Point> pathFigureDCSide = new List<Point>();
List<Point> polyLinePoints = new List<Point>(4);
int iteratorCount = iterator.Count;
for (int index = 0, previousIndex = -1; index < iteratorCount; )
{
if (!prevPrevStrokeNode.IsValid)
{
if (prevStrokeNode.IsValid)
{
//we're sliding our pointers forward
prevPrevStrokeNode = prevStrokeNode;
prevPrevStrokeNodeBounds = prevStrokeNodeBounds;
prevStrokeNode = emptyStrokeNode;
}
else
{
prevPrevStrokeNode = iterator[index++, previousIndex++];
prevPrevStrokeNodeBounds = prevPrevStrokeNode.GetBounds();
continue; //so we always check if index < iterator.Count
}
}
//we know prevPrevStrokeNode is valid
if (!prevStrokeNode.IsValid)
{
if (strokeNode.IsValid)
{
//we're sliding our pointers forward
prevStrokeNode = strokeNode;
prevStrokeNodeBounds = strokeNodeBounds;
strokeNode = emptyStrokeNode;
}
else
{
//get the next strokeNode, but don't automatically update previousIndex
prevStrokeNode = iterator[index++, previousIndex];
prevStrokeNodeBounds = prevStrokeNode.GetBounds();
RectCompareResult result =
FuzzyContains( prevStrokeNodeBounds,
prevPrevStrokeNodeBounds,
isStartOfSegment ? 99.99999d : percentIntersect);
if (result == RectCompareResult.Rect1ContainsRect2)
{
// this node already contains the prevPrevStrokeNodeBounds (PP):
//
// |------------|
// | |----| |
// | | PP | P |
// | |----| |
// |------------|
//
prevPrevStrokeNode = iterator[index - 1, prevPrevStrokeNode.Index - 1]; ;
prevPrevStrokeNodeBounds = Rect.Union(prevStrokeNodeBounds, prevPrevStrokeNodeBounds);
// at this point prevPrevStrokeNodeBounds already contains this node
// we can just ignore this node
prevStrokeNode = emptyStrokeNode;
// update previousIndex to point to this node
previousIndex = index - 1;
// go back to our main loop
continue;
}
else if (result == RectCompareResult.Rect2ContainsRect1)
{
// this prevPrevStrokeNodeBounds (PP) already contains this node:
//
// |------------|
// | |----||
// | PP | P ||
// | |----||
// |------------|
//
//prevPrevStrokeNodeBounds already contains this node
//we can just ignore this node
prevStrokeNode = emptyStrokeNode;
// go back to our main loop, but do not update previousIndex
// because it should continue to point to previousPrevious
continue;
}
Debug.Assert(!prevStrokeNode.GetConnectingQuad().IsEmpty, "prevStrokeNode.GetConnectingQuad() is Empty!");
// if neither was true, we now have two of our three nodes required to
// start our computation, we need to update previousIndex to point
// to our current, valid prevStrokeNode
previousIndex = index - 1;
continue; //so we always check if index < iterator.Count
}
}
//we know prevPrevStrokeNode and prevStrokeNode are both valid
if (!strokeNode.IsValid)
{
strokeNode = iterator[index++, previousIndex];
strokeNodeBounds = strokeNode.GetBounds();
RectCompareResult result =
FuzzyContains( strokeNodeBounds,
prevStrokeNodeBounds,
isStartOfSegment ? 99.99999 : percentIntersect);
RectCompareResult result2 =
FuzzyContains( strokeNodeBounds,
prevPrevStrokeNodeBounds,
isStartOfSegment ? 99.99999 : percentIntersect);
if ( isStartOfSegment &&
result == RectCompareResult.Rect1ContainsRect2 &&
result2 == RectCompareResult.Rect1ContainsRect2)
{
if (pathFigureABSide.Count > 0)
{
//we've started a stroke, we need to end it before resetting
//prevPrev
#if DEBUG_RENDERING_FEEDBACK
prevStrokeNode.GetPointsAtEndOfSegment(pathFigureABSide, pathFigureDCSide, debugDC, feedbackSize, showFeedback);
#else
prevStrokeNode.GetPointsAtEndOfSegment(pathFigureABSide, pathFigureDCSide);
#endif
//render
ReverseDCPointsRenderAndClear(context, pathFigureABSide, pathFigureDCSide, polyLinePoints, isEllipse, true/*clear the point collections*/);
}
//we're resetting
//prevPrevStrokeNode. We need to gen one
//without a connecting quad
prevPrevStrokeNode = iterator[index - 1, prevPrevStrokeNode.Index - 1];
prevPrevStrokeNodeBounds = prevPrevStrokeNode.GetBounds();
prevStrokeNode = emptyStrokeNode;
strokeNode = emptyStrokeNode;
// increment previousIndex to to point to this node
previousIndex = index - 1;
continue;
}
else if (result == RectCompareResult.Rect1ContainsRect2)
{
// this node (C) already contains the prevStrokeNodeBounds (P):
//
// |------------|
// |----| | |----| |
// | PP | | | P | C |
// |----| | |----| |
// |------------|
//
//we have to generate a new stroke node that points
//to pp since the connecting quad from C to P could be empty
//if they have the same point
strokeNode = iterator[index - 1, prevStrokeNode.Index - 1];
if (!strokeNode.GetConnectingQuad().IsEmpty)
{
//only update prevStrokeNode if we have a valid connecting quad
prevStrokeNode = strokeNode;
prevStrokeNodeBounds = Rect.Union(strokeNodeBounds, prevStrokeNodeBounds);
// update previousIndex, since it should point to this node now
previousIndex = index - 1;
}
// at this point we can just ignore this node
strokeNode = emptyStrokeNode;
//strokeNodeBounds = empty;
prevAngle = double.MinValue; //invalidate
// go back to our main loop
continue;
}
else if (result == RectCompareResult.Rect2ContainsRect1)
{
// this prevStrokeNodeBounds (P) already contains this node (C):
//
// |------------|
// |----| | |----||
// | PP | | P | C ||
// |----| | |----||
// |------------|
//
//prevStrokeNodeBounds already contains this node
//we can just ignore this node
strokeNode = emptyStrokeNode;
// go back to our main loop, but do not update previousIndex
// because it should continue to point to previous
continue;
}
Debug.Assert(!strokeNode.GetConnectingQuad().IsEmpty, "strokeNode.GetConnectingQuad was empty, this is unexpected");
//
// NOTE: we do not check if C contains PP, or PP contains C because
// that indicates a change in direction, which we handle below
//
// if neither was true P and C are separate,
// we now have all three nodes required to
// start our computation, we need to update previousIndex to point
// to our current, valid prevStrokeNode
previousIndex = index - 1;
}
// see if we have an overlap between the first and third node
bool overlap = prevPrevStrokeNodeBounds.IntersectsWith(strokeNodeBounds);
// prevPrevStrokeNode, prevStrokeNode and strokeNode are all
// valid nodes now. Now we need to figure out what do add to our
// PathFigure. First calc bounds on the strokeNode we know we need to render
if (calculateBounds)
{
bounds.Union(prevStrokeNodeBounds);
}
// determine what points to add to pathFigureABSide and pathFigureDCSide
// from prevPrevStrokeNode
if (pathFigureABSide.Count == 0)
{
Debug.Assert(pathFigureDCSide.Count == 0);
if (calculateBounds)
{
bounds.Union(prevPrevStrokeNodeBounds);
}
if (isStartOfSegment && overlap)
{
//render a complete first stroke node or we can get artifacts
prevPrevStrokeNode.GetContourPoints(polyLinePoints);
AddFigureToStreamGeometryContext(context, polyLinePoints, prevPrevStrokeNode.IsEllipse/*isBezierFigure*/);
polyLinePoints.Clear();
}
// we're starting a new pathfigure
// we need to add parts of the prevPrevStrokeNode contour
// to pathFigureABSide and pathFigureDCSide
#if DEBUG_RENDERING_FEEDBACK
prevStrokeNode.GetPointsAtStartOfSegment(pathFigureABSide, pathFigureDCSide, debugDC, feedbackSize, showFeedback);
#else
prevStrokeNode.GetPointsAtStartOfSegment(pathFigureABSide, pathFigureDCSide);
#endif
//set our marker, we're no longer at the start of the stroke
isStartOfSegment = false;
}
if (prevAngle == double.MinValue)
{
//prevAngle is no longer valid
prevAngle = GetAngleBetween(prevPrevStrokeNode.Position, prevStrokeNode.Position);
}
double delta = GetAngleDeltaFromLast(prevStrokeNode.Position, strokeNode.Position, ref prevAngle);
bool directionChangedOverAbsoluteThreshold = Math.Abs(delta) > 90d && Math.Abs(delta) < (360d - 90d);
bool directionChangedOverOverlapThreshold = overlap && !(ignorePressure || strokeNode.PressureFactor == 1f) && Math.Abs(delta) > 30d && Math.Abs(delta) < (360d - 30d);
double prevArea = prevStrokeNodeBounds.Height * prevStrokeNodeBounds.Width;
double currArea = strokeNodeBounds.Height * strokeNodeBounds.Width;
bool areaChanged = !(prevArea == currArea && prevArea == (prevPrevStrokeNodeBounds.Height * prevPrevStrokeNodeBounds.Width));
bool areaChangeOverThreshold = false;
if (overlap && areaChanged)
{
if ((Math.Min(prevArea, currArea) / Math.Max(prevArea, currArea)) <= 0.90d)
{
//the min area is < 70% of the max area
areaChangeOverThreshold = true;
}
}
if (areaChanged || delta != 0.0d || index >= iteratorCount)
{
//the area changed between the three nodes OR there was an angle delta OR we're at the end
//of the stroke... either way, this is a significant node. If not, we're going to drop it.
if ((overlap && (directionChangedOverOverlapThreshold || areaChangeOverThreshold)) ||
directionChangedOverAbsoluteThreshold)
{
//
// we need to stop the pathfigure at P
// and render the pathfigure
//
// |--| |--| |--||--| |------|
// |PP|------|P | |PP||P | |PP P C|
// |--| |--| |--||--| |------|
// / |C |
// |--| |--|
// |C |
// |--|
#if DEBUG_RENDERING_FEEDBACK
prevStrokeNode.GetPointsAtEndOfSegment(pathFigureABSide, pathFigureDCSide, debugDC, feedbackSize, showFeedback);
#else
//end the figure
prevStrokeNode.GetPointsAtEndOfSegment(pathFigureABSide, pathFigureDCSide);
#endif
//render
ReverseDCPointsRenderAndClear(context, pathFigureABSide, pathFigureDCSide, polyLinePoints, isEllipse, true/*clear the point collections*/);
if (areaChangeOverThreshold)
{
//render a complete stroke node or we can get artifacts
prevStrokeNode.GetContourPoints(polyLinePoints);
AddFigureToStreamGeometryContext(context, polyLinePoints, prevStrokeNode.IsEllipse/*isBezierFigure*/);
polyLinePoints.Clear();
}
}
else
{
//
// direction didn't change over the threshold, add the midpoint data
// |--| |--|
// |PP|------|P |
// |--| |--|
// \
// |--|
// |C |
// |--|
bool endSegment; //flag that tell us if we missed an intersection
#if DEBUG_RENDERING_FEEDBACK
strokeNode.GetPointsAtMiddleSegment(prevStrokeNode, delta, pathFigureABSide, pathFigureDCSide, out endSegment, debugDC, feedbackSize, showFeedback);
#else
strokeNode.GetPointsAtMiddleSegment(prevStrokeNode, delta, pathFigureABSide, pathFigureDCSide, out endSegment);
#endif
if (endSegment)
{
//we have a missing intersection, we need to end the
//segment at P
#if DEBUG_RENDERING_FEEDBACK
prevStrokeNode.GetPointsAtEndOfSegment(pathFigureABSide, pathFigureDCSide, debugDC, feedbackSize, showFeedback);
#else
//end the figure
prevStrokeNode.GetPointsAtEndOfSegment(pathFigureABSide, pathFigureDCSide);
#endif
//render
ReverseDCPointsRenderAndClear(context, pathFigureABSide, pathFigureDCSide, polyLinePoints, isEllipse, true/*clear the point collections*/);
}
}
}
//
// either way... slide our pointers forward, to do this, we simply mark
// our first pointer as 'empty'
//
prevPrevStrokeNode = emptyStrokeNode;
prevPrevStrokeNodeBounds = empty;
}
//
// anything left to render?
//
if (prevPrevStrokeNode.IsValid)
{
if (prevStrokeNode.IsValid)
{
if (calculateBounds)
{
bounds.Union(prevPrevStrokeNodeBounds);
bounds.Union(prevStrokeNodeBounds);
}
Debug.Assert(!strokeNode.IsValid);
//
// we never made it to strokeNode, render two points, OR
// strokeNode was a dupe
//
if (pathFigureABSide.Count > 0)
{
#if DEBUG_RENDERING_FEEDBACK
prevStrokeNode.GetPointsAtEndOfSegment(pathFigureABSide, pathFigureDCSide, debugDC, feedbackSize, showFeedback);
#else
//
// strokeNode was a dupe, we just need to render the end of the stroke
// which is at prevStrokeNode
//
prevStrokeNode.GetPointsAtEndOfSegment(pathFigureABSide, pathFigureDCSide);
#endif
//render
ReverseDCPointsRenderAndClear(context, pathFigureABSide, pathFigureDCSide, polyLinePoints, isEllipse, false/*clear the point collections*/);
}
else
{
// we've only seen two points to render
Debug.Assert(pathFigureDCSide.Count == 0);
//contains all the logic to render two stroke nodes
RenderTwoStrokeNodes( context,
prevPrevStrokeNode,
prevPrevStrokeNodeBounds,
prevStrokeNode,
prevStrokeNodeBounds,
pathFigureABSide,
pathFigureDCSide,
polyLinePoints
#if DEBUG_RENDERING_FEEDBACK
,debugDC,
feedbackSize,
showFeedback
#endif
);
}
}
else
{
if (calculateBounds)
{
bounds.Union(prevPrevStrokeNodeBounds);
}
// we only have a single point to render
Debug.Assert(pathFigureABSide.Count == 0);
prevPrevStrokeNode.GetContourPoints(pathFigureABSide);
AddFigureToStreamGeometryContext(context, pathFigureABSide, prevPrevStrokeNode.IsEllipse/*isBezierFigure*/);
}
}
else if (prevStrokeNode.IsValid && strokeNode.IsValid)
{
if (calculateBounds)
{
bounds.Union(prevStrokeNodeBounds);
bounds.Union(strokeNodeBounds);
}
// typical case, we hit the end of the stroke
// see if we need to start a stroke, or just end one
if (pathFigureABSide.Count > 0)
{
#if DEBUG_RENDERING_FEEDBACK
strokeNode.GetPointsAtEndOfSegment(pathFigureABSide, pathFigureDCSide, debugDC, feedbackSize, showFeedback);
#else
strokeNode.GetPointsAtEndOfSegment(pathFigureABSide, pathFigureDCSide);
#endif
//render
ReverseDCPointsRenderAndClear(context, pathFigureABSide, pathFigureDCSide, polyLinePoints, isEllipse, false/*clear the point collections*/);
if (FuzzyContains(strokeNodeBounds, prevStrokeNodeBounds, 70d) != RectCompareResult.NoItersection)
{
//render a complete stroke node or we can get artifacts
strokeNode.GetContourPoints(polyLinePoints);
AddFigureToStreamGeometryContext(context, polyLinePoints, strokeNode.IsEllipse/*isBezierFigure*/);
}
}
else
{
Debug.Assert(pathFigureDCSide.Count == 0);
//contains all the logic to render two stroke nodes
RenderTwoStrokeNodes( context,
prevStrokeNode,
prevStrokeNodeBounds,
strokeNode,
strokeNodeBounds,
pathFigureABSide,
pathFigureDCSide,
polyLinePoints
#if DEBUG_RENDERING_FEEDBACK
,debugDC,
feedbackSize,
showFeedback
#endif
);
}
}
}
finally
{
context.Close();
geometry.Freeze();
}
}
}
/// <summary>
/// Helper function to find out whether a point is inside the lasso
/// </summary>
private bool SegmentWithinLasso(StrokeNode strokeNode, double fIndex)
{
bool currentSegmentWithinLasso;
if (DoubleUtil.AreClose(fIndex, StrokeFIndices.BeforeFirst))
{
// This should check against the very first stroke node
currentSegmentWithinLasso = this.Contains(strokeNode.GetPointAt(0f));
}
else if (DoubleUtil.AreClose(fIndex, StrokeFIndices.AfterLast))
{
// This should check against the last stroke node
currentSegmentWithinLasso = this.Contains(strokeNode.Position);
}
else
{
currentSegmentWithinLasso = this.Contains(strokeNode.GetPointAt(fIndex));
}
return currentSegmentWithinLasso;
}
/// <summary>
/// GetPointsAtMiddleSegment
/// </summary>
internal void GetPointsAtMiddleSegment(StrokeNode previous,
double angleBetweenNodes,
List <Point> abPoints,
List <Point> dcPoints,
out bool missingIntersection
#if DEBUG_RENDERING_FEEDBACK
, DrawingContext debugDC, double feedbackSize, bool showFeedback
#endif
)
{
missingIntersection = false;
if (IsValid && previous.IsValid)
{
Quad quad1 = previous.ConnectingQuad;
if (!quad1.IsEmpty)
{
Quad quad2 = ConnectingQuad;
if (!quad2.IsEmpty)
{
if (IsEllipse)
{
Rect node1Bounds = _operations.GetNodeBounds(previous._lastNode);
Rect node2Bounds = _operations.GetNodeBounds(_lastNode);
Rect node3Bounds = _operations.GetNodeBounds(_thisNode);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(null, new Pen(Brushes.Pink, feedbackSize / 2), _lastNode.Position, node2Bounds.Width / 2, node2Bounds.Height / 2);
}
#endif
if (angleBetweenNodes == 0.0d || ((quad1.B == quad2.A) && (quad1.C == quad2.D)))
{
//quads connections are the same, just add them
abPoints.Add(quad1.B);
dcPoints.Add(quad1.C);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize, feedbackSize);
}
#endif
}
else if (angleBetweenNodes > 0.0)
{
//the stroke angled towards the AB side
//this part is easy
if (quad1.B == quad2.A)
{
abPoints.Add(quad1.B);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize, feedbackSize);
}
#endif
}
else
{
Point intersection = GetIntersection(quad1.A, quad1.B, quad2.A, quad2.B);
Rect union = Rect.Union(node1Bounds, node2Bounds);
union.Inflate(1.0, 1.0);
//make sure we're not off in space
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize * 1.5, feedbackSize * 1.5);
debugDC.DrawEllipse(Brushes.Red, null, quad2.A, feedbackSize, feedbackSize);
}
#endif
if (union.Contains(intersection))
{
abPoints.Add(intersection);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Orange, null, intersection, feedbackSize, feedbackSize);
}
#endif
}
else
{
//if we missed the intersection we'll need to close the stroke segment
//this work is done in StrokeRenderer
missingIntersection = true;
return; //we're done.
}
}
if (quad1.C == quad2.D)
{
dcPoints.Add(quad1.C);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize, feedbackSize);
}
#endif
}
else
{
//add instructions to arc from quad1.C to quad2.D in reverse order (since we walk this array backwards to render)
dcPoints.Add(quad1.C);
dcPoints.Add(new Point(node2Bounds.Width, node2Bounds.Height));
dcPoints.Add(StrokeRenderer.ArcToMarker);
dcPoints.Add(quad2.D);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Blue, null, quad2.D, feedbackSize, feedbackSize);
}
#endif
}
}
else
{
//the stroke angled towards the CD side
//this part is easy
if (quad1.C == quad2.D)
{
dcPoints.Add(quad1.C);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize, feedbackSize);
}
#endif
}
else
{
Point intersection = GetIntersection(quad1.D, quad1.C, quad2.D, quad2.C);
Rect union = Rect.Union(node1Bounds, node2Bounds);
union.Inflate(1.0, 1.0);
//make sure we're not off in space
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize * 1.5, feedbackSize * 1.5);
debugDC.DrawEllipse(Brushes.Blue, null, quad2.D, feedbackSize, feedbackSize);
}
#endif
if (union.Contains(intersection))
{
dcPoints.Add(intersection);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Orange, null, intersection, feedbackSize, feedbackSize);
}
#endif
}
else
{
//if we missed the intersection we'll need to close the stroke segment
//this work is done in StrokeRenderer
missingIntersection = true;
return; //we're done.
}
}
if (quad1.B == quad2.A)
{
abPoints.Add(quad1.B);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize, feedbackSize);
}
#endif
}
else
{
//we need to arc between quad1.B and quad2.A along node2
abPoints.Add(quad1.B);
abPoints.Add(StrokeRenderer.ArcToMarker);
abPoints.Add(new Point(node2Bounds.Width, node2Bounds.Height));
abPoints.Add(quad2.A);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Red, null, quad2.A, feedbackSize, feedbackSize);
}
#endif
}
}
}
else
{
//rectangle
int indexA = -1;
int indexB = -1;
int indexC = -1;
int indexD = -1;
Vector[] vertices = _operations.GetVertices();
double pressureFactor = _lastNode.PressureFactor;
for (int i = 0; i < vertices.Length; i++)
{
Point point = _lastNode.Position + (vertices[i % vertices.Length] * pressureFactor);
if (point == quad2.A)
{
indexA = i;
}
if (point == quad1.B)
{
indexB = i;
}
if (point == quad1.C)
{
indexC = i;
}
if (point == quad2.D)
{
indexD = i;
}
}
if (indexA == -1 || indexB == -1 || indexC == -1 || indexD == -1)
{
Debug.Assert(false, "Couldn't find all 4 indexes in StrokeNodeOperations.GetPointsAtMiddleSegment");
return;
}
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawRectangle(null, new Pen(Brushes.Pink, feedbackSize / 2), _operations.GetNodeBounds(_lastNode));
debugDC.DrawEllipse(Brushes.Red, null, quad2.A, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Green, null, quad1.B, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Yellow, null, quad1.C, feedbackSize, feedbackSize);
debugDC.DrawEllipse(Brushes.Blue, null, quad2.D, feedbackSize, feedbackSize);
}
#endif
Rect node3Rect = _operations.GetNodeBounds(_thisNode);
//take care of a-b first
if (indexA == indexB)
{
//quad connection is the same, just add it
if (!node3Rect.Contains(quad1.B))
{
abPoints.Add(quad1.B);
}
}
else if ((indexA == 0 && indexB == 3) || ((indexA != 3 || indexB != 0) && (indexA > indexB)))
{
if (!node3Rect.Contains(quad1.B))
{
abPoints.Add(quad1.B);
}
if (!node3Rect.Contains(quad2.A))
{
abPoints.Add(quad2.A);
}
}
else
{
Point intersection = GetIntersection(quad1.A, quad1.B, quad2.A, quad2.B);
Rect node12 = Rect.Union(_operations.GetNodeBounds(previous._lastNode), _operations.GetNodeBounds(_lastNode));
node12.Inflate(1.0, 1.0);
//make sure we're not off in space
if (node12.Contains(intersection))
{
abPoints.Add(intersection);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Orange, null, intersection, feedbackSize, feedbackSize * 1.5);
}
#endif
}
else
{
//if we missed the intersection we'll need to close the stroke segment
//this work is done in StrokeRenderer.
missingIntersection = true;
return; //we're done.
}
}
// now take care of c-d.
if (indexC == indexD)
{
//quad connection is the same, just add it
if (!node3Rect.Contains(quad1.C))
{
dcPoints.Add(quad1.C);
}
}
else if ((indexC == 0 && indexD == 3) || ((indexC != 3 || indexD != 0) && (indexC > indexD)))
{
if (!node3Rect.Contains(quad1.C))
{
dcPoints.Add(quad1.C);
}
if (!node3Rect.Contains(quad2.D))
{
dcPoints.Add(quad2.D);
}
}
else
{
Point intersection = GetIntersection(quad1.D, quad1.C, quad2.D, quad2.C);
Rect node12 = Rect.Union(_operations.GetNodeBounds(previous._lastNode), _operations.GetNodeBounds(_lastNode));
node12.Inflate(1.0, 1.0);
//make sure we're not off in space
if (node12.Contains(intersection))
{
dcPoints.Add(intersection);
#if DEBUG_RENDERING_FEEDBACK
if (showFeedback)
{
debugDC.DrawEllipse(Brushes.Orange, null, intersection, feedbackSize, feedbackSize * 1.5);
}
#endif
}
else
{
//if we missed the intersection we'll need to close the stroke segment
//this work is done in StrokeRenderer.
missingIntersection = true;
return; //we're done.
}
}
}
}
}
}
}
/// <summary>
/// This method tells whether the contour of a given stroke node
/// intersects with the contour of this node. The contours of both nodes
/// include their connecting quadrangles.
/// </summary>
/// <param name="hitNode"></param>
/// <returns></returns>
internal bool HitTest(StrokeNode hitNode)
{
if (!IsValid || !hitNode.IsValid)
{
return false;
}
IEnumerable<ContourSegment> hittingContour = hitNode.GetContourSegments();
return _operations.HitTest(_lastNode, _thisNode, ConnectingQuad, hittingContour);
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="newFIndices"></param>
/// <param name="strokeNode"></param>
public LassoCrossing(StrokeFIndices newFIndices, StrokeNode strokeNode)
{
System.Diagnostics.Debug.Assert(!newFIndices.IsEmpty);
System.Diagnostics.Debug.Assert(strokeNode.IsValid);
FIndices = newFIndices;
StartNode = EndNode = strokeNode;
}
/// <summary>
/// Finds out if a given node intersects with this one,
/// and returns findices of the intersection.
/// </summary>
/// <param name="hitNode"></param>
/// <returns></returns>
internal StrokeFIndices CutTest(StrokeNode hitNode)
{
if ((IsValid == false) || (hitNode.IsValid == false))
{
return StrokeFIndices.Empty;
}
IEnumerable<ContourSegment> hittingContour = hitNode.GetContourSegments();
// If the node contours intersect, the result is a pair of findices
// this segment should be cut at to let the hitNode's contour through it.
StrokeFIndices cutAt = _operations.CutTest(_lastNode, _thisNode, ConnectingQuad, hittingContour);
return (_index == 0) ? cutAt : BindFIndices(cutAt);
}
/// <summary>
/// Helper routine to render two distinct stroke nodes
/// </summary>
private static void RenderTwoStrokeNodes( StreamGeometryContext context,
StrokeNode strokeNodePrevious,
Rect strokeNodePreviousBounds,
StrokeNode strokeNodeCurrent,
Rect strokeNodeCurrentBounds,
List<Point> pointBuffer1,
List<Point> pointBuffer2,
List<Point> pointBuffer3
#if DEBUG_RENDERING_FEEDBACK
,DrawingContext debugDC,
double feedbackSize,
bool showFeedback
#endif
)
{
Debug.Assert(pointBuffer1 != null);
Debug.Assert(pointBuffer2 != null);
Debug.Assert(pointBuffer3 != null);
Debug.Assert(context != null);
//see if we need to render a quad - if there is not at least a 70% overlap
if (FuzzyContains(strokeNodePreviousBounds, strokeNodeCurrentBounds, 70d) != RectCompareResult.NoItersection)
{
//we're between 100% and 70% overlapped
//just render two distinct figures with a connecting quad (if needed)
strokeNodePrevious.GetContourPoints(pointBuffer1);
AddFigureToStreamGeometryContext(context, pointBuffer1, strokeNodePrevious.IsEllipse/*isBezierFigure*/);
Quad quad = strokeNodeCurrent.GetConnectingQuad();
if (!quad.IsEmpty)
{
pointBuffer3.Add(quad.A);
pointBuffer3.Add(quad.B);
pointBuffer3.Add(quad.C);
pointBuffer3.Add(quad.D);
AddFigureToStreamGeometryContext(context, pointBuffer3, false/*isBezierFigure*/);
}
strokeNodeCurrent.GetContourPoints(pointBuffer2);
AddFigureToStreamGeometryContext(context, pointBuffer2, strokeNodeCurrent.IsEllipse/*isBezierFigure*/);
}
else
{
//we're less than 70% overlapped, it's safe to run our optimization
#if DEBUG_RENDERING_FEEDBACK
strokeNodeCurrent.GetPointsAtStartOfSegment(pointBuffer1, pointBuffer2, debugDC, feedbackSize, showFeedback);
strokeNodeCurrent.GetPointsAtEndOfSegment(pointBuffer1, pointBuffer2, debugDC, feedbackSize, showFeedback);
#else
strokeNodeCurrent.GetPointsAtStartOfSegment(pointBuffer1, pointBuffer2);
strokeNodeCurrent.GetPointsAtEndOfSegment(pointBuffer1, pointBuffer2);
#endif
//render
ReverseDCPointsRenderAndClear(context, pointBuffer1, pointBuffer2, pointBuffer3, strokeNodeCurrent.IsEllipse, false/*clear the point collections*/);
}
}
internal StrokeIntersection[] HitTest(StrokeNodeIterator iterator)
{
System.Diagnostics.Debug.Assert(_points != null);
System.Diagnostics.Debug.Assert(iterator != null);
if (_points.Count < 3)
{
//
// it takes at least 3 points to create a lasso
//
return(Array.Empty <StrokeIntersection>());
}
//
// We're about to perform hit testing with a lasso.
// To do so we need to iterate through each StrokeNode.
// As we do, we calculate the bounding rect between it
// and the previous StrokeNode and store this in 'currentStrokeSegmentBounds'
//
// Next, we check to see if that StrokeNode pair's bounding box intersects
// with the bounding box of the Lasso points. If not, we continue iterating through
// StrokeNode pairs.
//
// If it does, we do a more granular hit test by pairing points in the Lasso, getting
// their bounding box and seeing if that bounding box intersects our current StrokeNode
// pair
//
Point lastNodePosition = new Point();
Point lassoLastPoint = _points[_points.Count - 1];
Rect currentStrokeSegmentBounds = Rect.Empty;
// Initilize the current crossing to be an empty one
LassoCrossing currentCrossing = LassoCrossing.EmptyCrossing;
// Creat a list to hold all the crossings
List <LassoCrossing> crossingList = new List <LassoCrossing>();
for (int i = 0; i < iterator.Count; i++)
{
StrokeNode strokeNode = iterator[i];
Rect nodeBounds = strokeNode.GetBounds();
currentStrokeSegmentBounds.Union(nodeBounds);
// Skip the node if it's outside of the lasso's bounds
if (currentStrokeSegmentBounds.IntersectsWith(_bounds) == true)
{
// currentStrokeSegmentBounds, made up of the bounding box of
// this StrokeNode unioned with the last StrokeNode,
// intersects the lasso bounding box.
//
// Now we need to iterate through the lasso points and find out where they cross
//
Point lastPoint = lassoLastPoint;
foreach (Point point in _points)
{
//
// calculate a segment of the lasso from the last point
// to the current point
//
Rect lassoSegmentBounds = new Rect(lastPoint, point);
//
// see if this lasso segment intersects with the current stroke segment
//
if (!currentStrokeSegmentBounds.IntersectsWith(lassoSegmentBounds))
{
lastPoint = point;
continue;
}
//
// the lasso segment DOES intersect with the current stroke segment
// find out precisely where
//
StrokeFIndices strokeFIndices = strokeNode.CutTest(lastPoint, point);
lastPoint = point;
if (strokeFIndices.IsEmpty)
{
// current lasso segment does not hit the stroke segment, continue with the next lasso point
continue;
}
// Create a potentially new crossing for the current hit testing result.
LassoCrossing potentialNewCrossing = new LassoCrossing(strokeFIndices, strokeNode);
// Try to merge with the current crossing. If the merge is succussful (return true), the new crossing is actually
// continueing the current crossing, so do not start a new crossing. Otherwise, start a new one and add the existing
// one to the list.
if (!currentCrossing.Merge(potentialNewCrossing))
{
// start a new crossing and add the existing on to the list
crossingList.Add(currentCrossing);
currentCrossing = potentialNewCrossing;
}
}
}
// Continue with the next node
currentStrokeSegmentBounds = nodeBounds;
lastNodePosition = strokeNode.Position;
}
// Adding the last crossing to the list, if valid
if (!currentCrossing.IsEmpty)
{
crossingList.Add(currentCrossing);
}
// Handle the special case of no intersection at all
if (crossingList.Count == 0)
{
// the stroke was either completely inside the lasso
// or outside the lasso
if (this.Contains(lastNodePosition))
{
StrokeIntersection[] strokeIntersections = new StrokeIntersection[1];
strokeIntersections[0] = StrokeIntersection.Full;
return(strokeIntersections);
}
else
{
return(Array.Empty <StrokeIntersection>());
}
}
// It is still possible that the current crossing list is not sorted or overlapping.
// Sort the list and merge the overlapping ones.
SortAndMerge(ref crossingList);
// Produce the hit test results and store them in a list
List <StrokeIntersection> strokeIntersectionList = new List <StrokeIntersection>();
ProduceHitTestResults(crossingList, strokeIntersectionList);
return(strokeIntersectionList.ToArray());
}
/// <summary>
/// Merge two crossings into one.
/// </summary>
/// <param name="crossing"></param>
/// <returns>Return true if these two crossings are actually overlapping and merged; false otherwise</returns>
public bool Merge(LassoCrossing crossing)
{
if (crossing.IsEmpty)
{
return false;
}
if (FIndices.IsEmpty && !crossing.IsEmpty)
{
FIndices = crossing.FIndices;
StartNode = crossing.StartNode;
EndNode = crossing.EndNode;
return true;
}
if(DoubleUtil.GreaterThanOrClose(crossing.FIndices.EndFIndex, FIndices.BeginFIndex) &&
DoubleUtil.GreaterThanOrClose(FIndices.EndFIndex, crossing.FIndices.BeginFIndex))
{
if (DoubleUtil.LessThan(crossing.FIndices.BeginFIndex, FIndices.BeginFIndex))
{
FIndices.BeginFIndex = crossing.FIndices.BeginFIndex;
StartNode = crossing.StartNode;
}
if (DoubleUtil.GreaterThan(crossing.FIndices.EndFIndex, FIndices.EndFIndex))
{
FIndices.EndFIndex = crossing.FIndices.EndFIndex;
EndNode = crossing.EndNode;
}
return true;
}
return false;
}
