public static PathSplitData SplitBezierPathEvenly(BezierPath bezierPath, float spacing, float accuracy)
{
var splitData = new PathSplitData();
splitData.vertices.Add(bezierPath[0]);
splitData.tangents.Add(
CubicBezierUtility.EvaluateCurveDerivative(bezierPath.GetPointsInSegment(0), 0).normalized);
splitData.cumulativeLength.Add(0);
splitData.anchorVertexMap.Add(0);
splitData.minMax.AddValue(bezierPath[0]);
var prevPointOnPath = bezierPath[0];
var lastAddedPoint = bezierPath[0];
float currentPathLength = 0;
float dstSinceLastVertex = 0;
// Go through all segments and split up into vertices
for (var segmentIndex = 0; segmentIndex < bezierPath.NumSegments; segmentIndex++)
{
var segmentPoints = bezierPath.GetPointsInSegment(segmentIndex);
var estimatedSegmentLength = CubicBezierUtility.EstimateCurveLength(
segmentPoints[0],
segmentPoints[1],
segmentPoints[2],
segmentPoints[3]);
var divisions = Mathf.CeilToInt(estimatedSegmentLength * accuracy);
var increment = 1f / divisions;
for (var t = increment; t <= 1; t += increment)
{
var isLastPointOnPath = (t + increment > 1 && segmentIndex == bezierPath.NumSegments - 1);
if (isLastPointOnPath)
{
t = 1;
}
var pointOnPath = CubicBezierUtility.EvaluateCurve(segmentPoints, t);
dstSinceLastVertex += (pointOnPath - prevPointOnPath).magnitude;
// If vertices are now too far apart, go back by amount we overshot by
if (dstSinceLastVertex > spacing)
{
var overshootDst = dstSinceLastVertex - spacing;
pointOnPath += (prevPointOnPath - pointOnPath).normalized * overshootDst;
t -= increment;
}
if (dstSinceLastVertex >= spacing || isLastPointOnPath)
{
currentPathLength += (lastAddedPoint - pointOnPath).magnitude;
splitData.cumulativeLength.Add(currentPathLength);
splitData.vertices.Add(pointOnPath);
splitData.tangents.Add(CubicBezierUtility.EvaluateCurveDerivative(segmentPoints, t).normalized);
splitData.minMax.AddValue(pointOnPath);
dstSinceLastVertex = 0;
lastAddedPoint = pointOnPath;
}
prevPointOnPath = pointOnPath;
}
splitData.anchorVertexMap.Add(splitData.vertices.Count - 1);
}
return(splitData);
}
public static PathSplitData SplitBezierPathByAngleError(
BezierPath bezierPath,
float maxAngleError,
float minVertexDst,
float accuracy)
{
var splitData = new PathSplitData();
splitData.vertices.Add(bezierPath[0]);
splitData.tangents.Add(
CubicBezierUtility.EvaluateCurveDerivative(bezierPath.GetPointsInSegment(0), 0).normalized);
splitData.cumulativeLength.Add(0);
splitData.anchorVertexMap.Add(0);
splitData.minMax.AddValue(bezierPath[0]);
var prevPointOnPath = bezierPath[0];
var lastAddedPoint = bezierPath[0];
float currentPathLength = 0;
float dstSinceLastVertex = 0;
// Go through all segments and split up into vertices
for (var segmentIndex = 0; segmentIndex < bezierPath.NumSegments; segmentIndex++)
{
var segmentPoints = bezierPath.GetPointsInSegment(segmentIndex);
var estimatedSegmentLength = CubicBezierUtility.EstimateCurveLength(
segmentPoints[0],
segmentPoints[1],
segmentPoints[2],
segmentPoints[3]);
var divisions = Mathf.CeilToInt(estimatedSegmentLength * accuracy);
var increment = 1f / divisions;
for (var t = increment; t <= 1; t += increment)
{
var isLastPointOnPath = (t + increment > 1 && segmentIndex == bezierPath.NumSegments - 1);
if (isLastPointOnPath)
{
t = 1;
}
var pointOnPath = CubicBezierUtility.EvaluateCurve(segmentPoints, t);
var nextPointOnPath = CubicBezierUtility.EvaluateCurve(segmentPoints, t + increment);
// angle at current point on path
var localAngle = 180 - MathUtility.MinAngle(prevPointOnPath, pointOnPath, nextPointOnPath);
// angle between the last added vertex, the current point on the path, and the next point on the path
var angleFromPrevVertex = 180 - MathUtility.MinAngle(lastAddedPoint, pointOnPath, nextPointOnPath);
var angleError = Mathf.Max(localAngle, angleFromPrevVertex);
if ((angleError > maxAngleError && dstSinceLastVertex >= minVertexDst) || isLastPointOnPath)
{
currentPathLength += (lastAddedPoint - pointOnPath).magnitude;
splitData.cumulativeLength.Add(currentPathLength);
splitData.vertices.Add(pointOnPath);
splitData.tangents.Add(CubicBezierUtility.EvaluateCurveDerivative(segmentPoints, t).normalized);
splitData.minMax.AddValue(pointOnPath);
dstSinceLastVertex = 0;
lastAddedPoint = pointOnPath;
}
else
{
dstSinceLastVertex += (pointOnPath - prevPointOnPath).magnitude;
}
prevPointOnPath = pointOnPath;
}
splitData.anchorVertexMap.Add(splitData.vertices.Count - 1);
}
return(splitData);
}
