public static List <int> GetCorners(InkStroke stroq, InkStroke oInkStroke)
{
List <int> corners = new List <int>(); // List of index of corners.
List <double> straws = new List <double>(); // List of length of straws at each inkStroke points.
List <double> temp = new List <double>();
double t, localMin;
int W = 3, i, localMinIndex;
corners.Add(0);
for (i = 0; i < W; i++)
{
straws.Add(0.0);
}
for (i = W; i < stroq.Points.Count - W; i++)
{
straws.Add(Distance(stroq.Points[i - W], stroq.Points[i + W]));
temp.Add(straws[i]);
}
for (i = stroq.Points.Count - W; i < stroq.Points.Count; i++)
{
straws.Add(0.0);
}
// Find the median and threshold.
if (temp.Count == 0)
{
Debug.WriteLine("Too few points. Try to draw more points.");
return(corners);
}
temp.Sort();
t = temp[temp.Count / 2] * 0.95;
// Find local minimum of potential corners.
for (i = W; i < stroq.Points.Count - W; i++)
{
if (straws[i] < t)
{
localMin = 100000.0;
localMinIndex = i;
while (i < stroq.Points.Count - W && straws[i] < t)
{
if (straws[i] < localMin)
{
localMin = straws[i];
localMinIndex = i;
}
i++;
}
corners.Add(localMinIndex);
}
}
corners.Add(stroq.Points.Count - 1);
// Do post process to the potential corners.
corners = PostProcessCorners(stroq, corners, straws);
// Remove corners on curve.
corners = CurveCheck(stroq, corners);
// Find original corners.
corners = ResampleToOriginal(stroq, oInkStroke, corners);
if (corners.Count != 0)
{
InkStroke cinkStroke = new InkStroke();
cinkStroke.Points.Add(stroq.Points[corners[0]]);
for (i = 1; i < corners.Count; i++)
{
cinkStroke.Points.Add(oInkStroke.Points[corners[i]]);
}
}
else
{
Debug.WriteLine("No corners found.");
}
return(corners);
}
// Determines the interspacing pixel distance between resampled points.
public static double DetermineResampleSpacing(InkStroke stroq)
{
Rect bound = stroq.BoundingRect;
return(Distance(new Point(bound.Left, bound.Top), new Point(bound.Right, bound.Bottom)) / 80.0);
}
