private static int DefaultBezierSubdivisions(CCVector2 p0, CCVector2 p1, CCVector2 p2)
{
CCVector2 p01 = CCVector2.Lerp(p0, p1, .5f);
CCVector2 p12 = CCVector2.Lerp(p1, p2, .5f);
float dist = ApproxDistance(p0, p01) + ApproxDistance(p01, p12) + ApproxDistance(p12, p2);
return((int)(dist * 0.10f));
}
private int BuildArcGeometryBuffer(CCVector2 p0, CCVector2 p1, float height, int subdivisions)
{
var edge01 = p1 - p0;
var p01mid = CCVector2.Lerp(p0, p1, 0.5f);
float width = edge01.Length();
float radius = (height / 2) + (width * width) / (height * 8);
edge01.Normalize();
var edge01t = new CCVector2(-edge01.Y, edge01.X);
var center = p01mid + edge01t * (radius - height);
float startAngle = PointToAngle(center, p0);
float endAngle = PointToAngle(center, p1);
float arcAngle;
if (height >= 0)
{
if (height < width / 2)
{
arcAngle = (Math.Abs(endAngle - startAngle) < Math.PI)
? endAngle - startAngle
: endAngle + (float)Math.PI * 2 - startAngle;
}
else
{
arcAngle = ((endAngle - startAngle) > Math.PI)
? endAngle - startAngle
: endAngle + (float)Math.PI * 2 - startAngle;
}
}
else
{
if (-height < width / 2)
{
arcAngle = (Math.Abs(endAngle - startAngle) < Math.PI)
? endAngle - startAngle
: endAngle - (float)Math.PI * 2 - startAngle;
}
else
{
arcAngle = ((endAngle - startAngle) > Math.PI)
? startAngle - endAngle
: endAngle - (float)Math.PI * 2 - startAngle;
}
}
return(BuildArcGeometryBuffer(center, Math.Abs(radius), subdivisions, startAngle, arcAngle));
}