public static List<LineSegment> fractalLineSegment(LineSegment ls, float maxOffset, float threshold)
{
// uncomment these lines to temporary disable line fractals
//List<LineSegment> dummy = new List<LineSegment>();
//dummy.Add(ls);
//return dummy;
s_lineFractalPerp = ls.getLine().getPerpVector();
s_lineFractalLength = ls.getLength();
return fractalLineSegment(ls, maxOffset, threshold, 1);
}
public static List<LineSegment> fractalLineSegment(LineSegment ls, float baseMaxOffset, float threshold, int depth)
{
// TODO fix for short line segments... it goes crazy! that or increase threshold, but still...
const int maxDepth = 6;
List<LineSegment> result = new List<LineSegment>();
// recursive base case
if (ls.getLengthSquared() < threshold || depth >= maxDepth)
{
result.Add(ls);
return result;
}
// calculate and offset midpt
// easy approach - midpt
Vector2 midpt = ls.getMidpoint();
// other approach - any pt on the line segment selected from a normal dist between the pts
// for whatever reason, this doesn't seem to work quite as well
//float percentBetween = RandomManager.nextNormalDistPercent(1);
//Vector2 midpt = ls.getLine().getPt(ls.p.X + (ls.q.X - ls.p.X) * percentBetween);
// Can calculate max offset for this segment either as proportion of the original max depth
// float maxOffset = maxOffset * (maxDepth - depth) / maxDepth;
// Or as a proportion of the original length of the line
float maxOffset = baseMaxOffset * ls.getLength() / s_lineFractalLength;
float offset = (float)(RandomManager.get().NextDouble() - 0.5f) * maxOffset;
// Can get offset direction either from current line segment or original line segment
// Vector2 dir = ls.getLine().getPerpVector();
Vector2 offsetDir = s_lineFractalPerp;
offsetDir.Normalize();
midpt += offset * offsetDir;
// recurse!
List<LineSegment> left = fractalLineSegment(new LineSegment(ls.p, midpt), maxOffset, threshold, depth+1);
List<LineSegment> right = fractalLineSegment(new LineSegment(midpt, ls.q), maxOffset, threshold, depth+1);
result.AddRange(left);
result.AddRange(right);
return result;
}