Hoe Tangent Offset of 3-Node Edge

The hoe tangent offset of a 3-node edge is defined as the ratio of the distance between the real and ideal mid-side node and the distance between the corner nodes of the edge.

If the mid-side node does not lie on the line connecting the corner nodes (that is the edge has a non-zero normal offset), then its projection on the line is used in the calculation.

HTEi = Hoe tangent offset of edge i
  = di / li

Figure 1.