/// <summary>
///
/// </summary>
/// <param name="originA"></param>
/// <param name="normalA"></param>
/// <param name="originB"></param>
/// <param name="normalB"></param>
/// <param name="point"></param>
/// <param name="axis"></param>
/// <returns></returns>
public static bool PlanePlaneIntersect(Vector3d originA, Vector3d normalA, Vector3d originB, Vector3d normalB, out Vector3d point, out Vector3d axis)
{
axis = Vector3d.Cross(normalA, normalB);
if (axis.SquareLength > 0.0)
{
var d = Vector3d.Reject(normalB, normalA);
point = ProjectToPlaneAlong(originA, originB, normalB, d);
return(true);
}
// normals are parallel, no unique solution
point = Vector3d.Zero;
return(false);
}
/// <summary>
/// Returns the aspect ratio of the triangle defined by 3 given points.
/// This is defined as the longest edge / shortest altitude.
/// </summary>
/// <param name="p0"></param>
/// <param name="p1"></param>
/// <param name="p2"></param>
/// <returns></returns>
public static double GetAspect(Vector3d p0, Vector3d p1, Vector3d p2)
{
double maxEdge = 0.0; // longest edge
double minAlt = Double.PositiveInfinity; // shortest altitude
Vector3d v0 = p1 - p0;
Vector3d v1 = p2 - p1;
Vector3d v2 = p0 - p2;
Sub(v0, v1);
Sub(v1, v2);
Sub(v2, v0);
return(Math.Sqrt(maxEdge) / Math.Sqrt(minAlt));
void Sub(Vector3d a, Vector3d b)
{
maxEdge = Math.Max(maxEdge, a.SquareLength);
minAlt = Math.Min(minAlt, Vector3d.Reject(b, a).SquareLength);
}
}
