/// <summary>
/// Calculates the similarity between this point and either 1 or 2 previous points representing a line segment
/// This function decides how appropriately this point would fit into a path joining 'point'
/// Comparison factors include: thickness of this valley compared to the last, valley colour, relative directions of the valleys
/// </summary>
/// <param name="point">Point to compare with</param>
/// <param name="previousPoint">Point prior to 'point', if applicable</param>
/// <returns>A floating-point similarity value between 0 and 1 where 1 is virtually identical</returns>
public SimilarityPack CalculateSimilarity(EdgePoint point, EdgePoint previousPoint = null)
{
SimilarityPack similarity = new SimilarityPack()
{
Colour = ImageMath.PixelDifference(ColourUnderPoint, point.ColourUnderPoint),
Direction = 1.0f,
Length = 1.0f,
Width = 1.0f,
Distance = 1.0f,
};
if (previousPoint != null)
{
Vector2 previousVector = new Vector2(point.X - previousPoint.X, point.Y - previousPoint.Y);
Vector2 currentVector = new Vector2(X - point.X, Y - point.Y);
if (previousVector.LengthSquared() > 0 && currentVector.LengthSquared() > 0)
{
// Direction similarity: Use the dot product of the normalised segment vectors
similarity.Direction = Vector2.Dot(previousVector / previousVector.Length(), currentVector / currentVector.Length());
// Length similarity: Use the smaller length divided by the bigger length.....?
similarity.Length = previousVector.Length() / currentVector.Length();
if (similarity.Length > 1.0f)
{
similarity.Length = 1.0f / similarity.Length; // swap the division operands lazily
}
}
}
if (point.LastPoint != null && LastPoint != null)
{
// Width similarity: Use the smaller width divided by the bigger width?
similarity.Width = Vector2.Distance(new Vector2(X, Y), new Vector2(LastPoint.X, LastPoint.Y)) /
Vector2.Distance(new Vector2(point.X, point.Y), new Vector2(point.LastPoint.X, point.LastPoint.Y));
if (similarity.Width > 1.0f)
{
similarity.Width = 1.0f / similarity.Width;
}
}
if (previousPoint == null)
{
float distanceToPoint = Vector2.Distance(new Vector2(X, Y), new Vector2(point.X, point.Y));
similarity.Distance = distanceToPoint > 0 ? 1.0f / distanceToPoint : 1.0f;
}
return(similarity);
}
private void ConnectEdgePoints(IEnumerable <EdgePoint>[] gridLines, List <Highlighter> highlighters)
{
// We want to join lines of similar edge lengths together. If we're coming from the tips of the fingers, we're fine increasing the width over time
// If we're coming from the opposite, we're fine decreasing the width
// Basically, we want to track whether the width increases or decreases as we go along
List <EdgePoint> finalEdgeList = new List <EdgePoint>();
for (int i = Input.LastClickPosition.X / gridInterval; i < gridLines.Count(); ++i)
{
EdgePoint mostSimilarPoint = null;
SimilarityPack highestSimilarity = new SimilarityPack();
foreach (EdgePoint p in gridLines[i])
{
SimilarityPack similarity;
if (finalEdgeList.Count == 0)
{
similarity = new SimilarityPack();
similarity.Distance = 1.0f / ((p.X - Input.LastClickPosition.X) * (p.X - Input.LastClickPosition.X) + (p.Y - Input.LastClickPosition.Y) * (p.Y - Input.LastClickPosition.Y));
}
else if (finalEdgeList.Count == 1)
{
similarity = p.CalculateSimilarity(finalEdgeList[0], null);
}
else
{
similarity = p.CalculateSimilarity(finalEdgeList[finalEdgeList.Count - 1], finalEdgeList[finalEdgeList.Count - 2]);
}
if (similarity.OverallSimilarity >= highestSimilarity.OverallSimilarity)
{
mostSimilarPoint = p;
highestSimilarity = similarity;
}
}
finalEdgeList.Add(mostSimilarPoint);
DebugInfo += highestSimilarity.Info + "\r\n";
}
for (int i = 1; i < finalEdgeList.Count; ++i)
{
highlighters.Add(new EdgeHighlighter(new Point(finalEdgeList[i - 1].X, finalEdgeList[i - 1].Y), new Point(finalEdgeList[i].X, finalEdgeList[i].Y))
{
Pen = new Pen(Color.Green, 1.0f)
});
}
}