/// <summary>
/// Cycles through a list of points and creates a fractal
/// version of the points by splitting each one in half and
/// moving it a random amount.
/// </summary>
/// <returns>A true if at least one point was changed.</returns>
public static bool StaggerPoints(
CenterPointList points,
MersenneRandom random,
float minimumDistance)
{
// Ignores blanks and null
if (points == null)
throw new ArgumentException("points cannot be null");
if (random == null)
throw new ArgumentException("random cannot be null");
if (points.Count < 2)
return false;
// Go through each set of points
CenterPointList newPoints = new CenterPointList();
bool changed = false;
for (int i = 0; i < points.Count - 1; i++)
{
// Get the points
CenterPoint p1 = points[i];
CenterPoint p2 = points[i + 1];
// Add the first point
newPoints.Add(p1);
// Get the distance
float distance = CalculateDistance(p1.Point, p2.Point);
if (distance > minimumDistance)
{
// These two are far enough to calculate a new point
CenterPoint mp =
new CenterPoint((p1.X + p2.X) / 2, (p1.Y + p2.Y) / 2);
float delta = distance * Constants.FractalDecay;
float diff = random.NextSingle(-delta, delta);
// Calculate the new point
float dy = p2.Y - p1.Y;
float dx = p2.X - p1.X;
if (dy == 0)
{
// This is a horizontal line
mp.Y += diff;
}
else if (dx == 0)
{
// This is a vertical line
mp.X += diff;
}
else
{
// Figure out the slope of the line
double theta1 = Math.Tanh(dy / dx);
double theta2 = theta1 - Math.PI / 2;
mp.X = (float) (mp.X + diff * Math.Cos(theta2));
mp.Y = (float) (mp.Y + diff * Math.Sin(theta2));
}
// Add the created point
newPoints.Add(mp);
changed = true;
}
// Add the second point
newPoints.Add(p2);
}
// See if we changes something
if (changed)
{
// Swap the points
points.Clear();
points.AddAll(newPoints);
newPoints.Clear();
}
// Return our status
return changed;
}
/// <summary>
/// Gets the distance between two points.
/// </summary>
public float GetDistance(CenterPoint point)
{
return Geometry.CalculateDistance(Point, point.Point);
}
/// <summary>
/// Draws a little widget in the center to indicate the center of
/// the segment point.
/// </summary>
private void RenderSegmentHandle(Context g, CenterPoint segmentPoint)
{
// Set up the variables
PointF p = new PointF(cx + segmentPoint.X, cy + segmentPoint.Y);
double s2 = (handleSize / 4) / scale;
// Draw a red circle
g.Color = new Color(0, 0, 0.75f);
g.Arc(p.X, p.Y, s2, 0, Math.PI * 2);
g.Fill();
}
