public static Point GetEdgeEndpointOnEllipse(Point oVertexALocation, double dVertexARadiusWidth, double dVertexARadiusHeight, Point oVertexBLocation, double angle = 0)
{
Debug.Assert(dVertexARadiusWidth >= 0);
Debug.Assert(dVertexARadiusHeight >= 0);
var sourcePoint = oVertexALocation;
var targetPoint = oVertexBLocation;
var dEdgeAngle = MathHelper.GetAngleBetweenPoints(sourcePoint, targetPoint);
if (angle != 0)
{
dEdgeAngle = (dEdgeAngle.ToDegrees() + angle).ToRadians();
}
var pt = new Point(
sourcePoint.X + (dVertexARadiusWidth * Math.Cos(dEdgeAngle)),
sourcePoint.Y - (dVertexARadiusHeight * Math.Sin(dEdgeAngle))
);
if (angle != 0)
{
pt = MathHelper.RotatePoint(pt, oVertexALocation, angle);
}
return(pt);
}
public static Point GetEdgeEndpointOnRectangle(Point sourcePos, Rect sourceBounds, Point targetPos, double angle = 0)
{
Func <Point, double, Point> rotate = (p, a) => angle == 0.0 ? p : MathHelper.RotatePoint(p, sourceBounds.Center(), a);
var tgt_pt = rotate(targetPos, -angle);
if (tgt_pt.X <= sourcePos.X)
{
var leftSide = Intersects(sourcePos.ToVector(), tgt_pt.ToVector(), sourceBounds.TopLeft().ToVector(), sourceBounds.BottomLeft().ToVector());
if (leftSide.HasValue)
{
return(rotate(new Point(leftSide.Value.X, leftSide.Value.Y), angle));
}
}
else
{
var rightSide = Intersects(sourcePos.ToVector(), tgt_pt.ToVector(), sourceBounds.TopRight().ToVector(), sourceBounds.BottomRight().ToVector());
if (rightSide.HasValue)
{
return(rotate(new Point(rightSide.Value.X, rightSide.Value.Y), angle));
}
}
if (tgt_pt.Y <= sourcePos.Y)
{
var topSide = Intersects(sourcePos.ToVector(), tgt_pt.ToVector(), sourceBounds.TopLeft().ToVector(), sourceBounds.TopRight().ToVector());
if (topSide.HasValue)
{
return(rotate(new Point(topSide.Value.X, topSide.Value.Y), angle));
}
}
else
{
var bottomSide = Intersects(sourcePos.ToVector(), tgt_pt.ToVector(), sourceBounds.BottomLeft().ToVector(), sourceBounds.BottomRight().ToVector());
if (bottomSide.HasValue)
{
return(rotate(new Point(bottomSide.Value.X, bottomSide.Value.Y), angle));
}
}
return(rotate(new Point(sourcePos.X, sourcePos.Y), angle));
}
public static Point GetEdgeEndpointOnRectangle(Point sourcePos, Rect sourceBounds, Point targetPos, double angle = 0)
{
var tgt_pt = targetPos;
if (angle != 0)
{
tgt_pt = MathHelper.RotatePoint(targetPos, sourceBounds.Center(), -angle);
}
var leftSide = Intersects(sourcePos.ToVector(), tgt_pt.ToVector(), sourceBounds.TopLeft().ToVector(), sourceBounds.BottomLeft().ToVector());
var bottomSide = Intersects(sourcePos.ToVector(), tgt_pt.ToVector(), sourceBounds.BottomLeft().ToVector(), sourceBounds.BottomRight().ToVector());
var rightSide = Intersects(sourcePos.ToVector(), tgt_pt.ToVector(), sourceBounds.TopRight().ToVector(), sourceBounds.BottomRight().ToVector());
var topSide = Intersects(sourcePos.ToVector(), tgt_pt.ToVector(), sourceBounds.TopLeft().ToVector(), sourceBounds.TopRight().ToVector());
var pt = new Point(sourcePos.X, sourcePos.Y);
// Get the rectangle side where intersection of the proposed Edge path occurred.
if (leftSide != null)
{
pt = new Point(leftSide.Value.X, leftSide.Value.Y);
}
else if (bottomSide != null)
{
pt = new Point(bottomSide.Value.X, bottomSide.Value.Y);
}
else if (rightSide != null)
{
pt = new Point(rightSide.Value.X, rightSide.Value.Y);
}
else if (topSide != null)
{
pt = new Point(topSide.Value.X, topSide.Value.Y);
}
if ((leftSide != null || bottomSide != null || rightSide != null || topSide != null) && angle != 0)
{
pt = MathHelper.RotatePoint(pt, sourceBounds.Center(), angle);
}
return(pt);
}