public void FlattenTo_SubdividesToCorrectError(double[] polygon, double acceptedError, int expectedNumSides)
{
var points = UnflattenArrayToPoints(polygon);
var resultingPoints = BezierTools.FlattenTo(points, acceptedError).ToArray();
Assert.Equal(1 + expectedNumSides, resultingPoints.Length);
}
public void FlattenTo_NoSubdivisionWhenLinearButOutOfOrder(double[] polygon)
{
var points = UnflattenArrayToPoints(polygon);
var result = BezierTools.FlattenTo(points, .001).ToArray();
Assert.Equal(4, result.Length);
var flattened = FlattenPointsToArray(result);
Assert.Equal(polygon, flattened);
}
public void FlattenTo_LimitsRecursiveDepth_10metersSubdividesToNoLessThan100thOfMillimeterByDefault()
{
// If a curve is 10 meters, how many subdivisions would reduce a segment length to below 0.01 millimeters?
// Take that as our maximum # of reasonable subdivisions for approximating a curve.
var maxDivisions = Math.Ceiling(Math.Log(10 * 1000 / .01) / Math.Log(2));
var points = UnflattenArrayToPoints(new double[] { 0, 0, 0, 1, 1, 1, 1, 0 });
var result = BezierTools.FlattenTo(points, 0).ToArray();
Assert.NotEmpty(result);
var actualDivisions = Math.Log(result.Length / 3 /* points per bezier */) / Math.Log(2);
Assert.InRange(actualDivisions, 1, maxDivisions);
}