pub fn joint_residuals(
kind: &JointKind,
a: &Connector<D>,
b: &Connector<D>,
at: &Coordinates,
scale: D,
) -> GeopResult<Vec<D>>Expand description
The residuals of a joint of kind between a — the first part’s
connector — and b, at the coordinates at (an angle in degrees),
where they are: each a length, a direction’s scaled by the part’s size
scale.
b’s origin is a’s moved along a’s axis by the distance, and along
its reference and the direction square to both by x and y; and as
the joint turns, b’s axis is parallel to a’s — facing either way, as
a pin in a hole may — with b’s reference a’s turned about a’s axis
by the angle (zero for a joint that does not turn), or b’s axis square
to a’s for a cross, or turned any way for a ball. Fails — infeasible —
where b is turned half a turn from what the angle says.