public override bool IsInsideDataArea {get;}

// nodes, edges of the triangle
var triNnodes = triangle.Nodes;
var triEdges = triangle.Edges;

// triangle geometry
var polygon = triangle.ToPolygon();
// triangle length
var triLength = triangle.Length;
// triangle area 
var triArea = triangle.Area;
// is the triangle "inside"
var isInsideTriangle = triangle.IsInsideDataArea;

// triangle aspect and slope  (radians)
var aspect = triangle.Aspect;
var slope = triangle.Slope;

// get centroid
var centroid = triangle.GetCentroid();

// get normal
var normal = triangle.GetNormal();

// get adjacent triangles
var adjTriangles = triangle.GetAdjacentTriangles();

// get area of triangle that falls between the z values
double minZ = 1.0;
double maxZ = 3.0;
IReadOnlyList<Coordinate3D> coords = triangle.GetPointsBetweenZs(minZ, maxZ);