public BezierSubdivision Prev() // Previous index at current level
{
var next = new BezierSubdivision(new List <Vector2>(Points), Level, Index - 1);
next.ScaleRight(-1);
next.Reverse();
return(next);
}
public BezierSubdivision Parent() // Parent subdivision (inverse of BezierSubdivide)
{
var parent = new BezierSubdivision(new List <Vector2>(Points), Level - 1, Index >> 1);
if ((Index & 1) == 0)
{
parent.ScaleRight(2);
}
else
{
parent.ScaleLeft(-1);
}
return(parent);
}
public static List <Vector2> MoveAnchorsToLength(List <Vector2> anchors, PathType pathType, double newLength, out PathType newPathType)
{
var newAnchors = new List <Vector2>();
var sliderPath = new SliderPath(pathType, anchors.ToArray(), newLength);
var maxSliderPath = new SliderPath(pathType, anchors.ToArray());
if (newLength > maxSliderPath.Distance)
{
// Extend linearly
switch (pathType)
{
case PathType.Bezier:
newPathType = PathType.Bezier;
newAnchors.AddRange(anchors);
newAnchors.Add(anchors.Last());
newAnchors.Add(sliderPath.PositionAt(1));
break;
case PathType.Catmull:
case PathType.PerfectCurve:
// Convert to bezier and then extend
newPathType = PathType.Bezier;
newAnchors = BezierConverter.ConvertToBezier(sliderPath).ControlPoints;
newAnchors.Add(anchors.Last());
newAnchors.Add(sliderPath.PositionAt(1));
break;
default:
newPathType = pathType;
newAnchors.AddRange(anchors);
newAnchors[newAnchors.Count - 1] = sliderPath.PositionAt(1);
break;
}
}
else
{
switch (sliderPath.Type)
{
case PathType.Catmull:
case PathType.Bezier:
newPathType = PathType.Bezier;
// Convert in case the path type is catmull
var convert = BezierConverter.ConvertToBezier(sliderPath).ControlPoints;
// Find the last bezier segment and the pixel length at that part
BezierSubdivision subdivision = null;
double totalLength = 0;
foreach (var bezierSubdivision in ChopAnchors(convert))
{
subdivision = bezierSubdivision;
var length = bezierSubdivision.SubdividedApproximationLength();
if (totalLength + length > newLength)
{
break;
}
totalLength += length;
newAnchors.AddRange(bezierSubdivision.Points);
}
if (subdivision == null)
{
break;
}
// Find T for the remaining pixel length
var t = subdivision.LengthToT(newLength - totalLength);
// ScaleRight the BezierSubdivision so the anchors end at T
subdivision.ScaleRight(t);
// Add the scaled anchors
newAnchors.AddRange(subdivision.Points);
break;
case PathType.PerfectCurve:
newPathType = PathType.PerfectCurve;
newAnchors.AddRange(anchors);
newAnchors[1] = sliderPath.PositionAt(0.5);
newAnchors[2] = sliderPath.PositionAt(1);
break;
default:
newPathType = pathType;
if (anchors.Count > 2)
{
// Find the section of the linear slider which contains the slider end
totalLength = 0;
foreach (var bezierSubdivision in ChopAnchorsLinear(anchors))
{
newAnchors.Add(bezierSubdivision.Points[0]);
var length = bezierSubdivision.Length();
if (totalLength + length > newLength)
{
break;
}
totalLength += length;
}
newAnchors.Add(sliderPath.PositionAt(1));
}
else
{
newAnchors.AddRange(anchors);
newAnchors[newAnchors.Count - 1] = sliderPath.PositionAt(1);
}
break;
}
}
return(newAnchors);
}
