Function analyse_blend 

pub fn analyse_blend(
    model: &Model,
    shape: &Shape,
    blend: &Shape,
    stations: usize,
    tol: Tolerances,
) -> OgeomResult<Vec<BlendContact>>

Measure a blend face against every face it shares an edge with.

Every number is sampled: stations points spread over each shared edge’s range, the surfaces read at the parameters the edge’s own pcurves give, so nothing is inverted and nothing is guessed. A blend that is tangent everywhere except between two stations reports zero, which is the honest limit of sampling and the reason the count is in the report.

An edge whose pcurve on either face is missing cannot be measured this way at all: it is reported with its gap and tangency_error set to infinity rather than quietly skipped, because a blend nobody can measure is not a blend anybody should trust. Its curvature_error is infinite on the same grounds, and so is that of an edge where no station gave a curvature on both sides.

Errors

OgeomError::Construction if blend is not a face of shape, or stations is less than two.