public static ProjectedCircle Project(Circle circle, Layer layer, Matrix4 transform)
{
// find axis endpoints
var rightVector = Vector.RightVectorFromNormal(circle.Normal);
var upVector = circle.Normal.Cross(rightVector).Normalize();
var pt = transform.Transform(circle.Center + (rightVector * circle.Radius));
var qt = transform.Transform(circle.Center + (upVector * circle.Radius));
var m = transform.Transform(circle.Center);
return(ProjectedCircle.FromConjugateDiameters(circle, layer, m, pt, qt));
}
public static ProjectedArc Project(Arc arc, Layer layer, Matrix4 transform)
{
// find the containing circle
var rightVector = Vector.RightVectorFromNormal(arc.Normal);
var upVector = arc.Normal.Cross(rightVector).Normalize();
var pt = transform.Transform(arc.Center + (rightVector * arc.Radius));
var qt = transform.Transform(arc.Center + (upVector * arc.Radius));
var m = transform.Transform(arc.Center);
var circle = ProjectedCircle.FromConjugateDiameters(null, layer, m, pt, qt);
// find the new start and end angles
var startPoint = transform.Transform(arc.EndPoint1);
var endPoint = transform.Transform(arc.EndPoint2);
var startAngle = (startPoint - circle.Center).ToAngle();
var endAngle = (endPoint - circle.Center).ToAngle();
return(new ProjectedArc(arc, layer, circle.Center, circle.RadiusX, circle.RadiusY, circle.Rotation, startAngle, endAngle, startPoint, endPoint));
}