Why is Actual Tread Depth wrong in sample project?

[Anonymous]

In the sample project, the Actual Tread Depth of one of the staircases is incorrect if you actually measure it.  To see it more clearly, you can modify the actual tread depth and it has no effect on the model (see screenshots).

Am I misunderstanding how actual tread depth works?  Why is not linked?

Also, is it possible to get the real tread depth of these stairs from the API without using just the geometry?

[RPTHOMAS108 · Accepted solution]

When stairs are based on a sketch the sketch defines the going/actual tread depth (previous method of drawing stairs).

If it is a sketch the goings can vary in length as indicated below. So there is no way of knowing the going other than by analysing sketch lines or actual geometry. Every sketch needs to have two boundaries (green lines) and goings (black lines). So you could determine intersections between black lines and green lines or black lines and blue line and then find minimum distances between such intersections. You would then have to take an average (most) but I don't know how useful that would be, is subjective. 

When stair is based on assembly stair going/actual tread depth is taken from parameter (newer method of drawing stairs).