cover curve merging

[Pomax]

it's implied in the text but there should just be a dedicated short chapter on merging curves by contructing new curves and performing MSE fitting or the like

[tbrowder]

And that would be a perfect time to mention the PDF ISO standard's graphics operators for Bezier curves:

c - x1 y1 x2 y2 x3 y3  : cubic Bezier to
v - x2 y2 x3 y3        : Bezier with (x1,x2) = current [path]
y - x1 y1 x3 y3        : Bezier with (x2 y2) = (x3 y3)

Using the Raku (formerly Perl 6) module 'PDF::Content' (see https://github.com/pdf-raku/PDF-Content-raku) those
operators are implemented in mnemonic routines

CurveTo,
CurveToInitial, and 
CurveToFinal,

respectively.

[Pomax]

Can you explain why you think those instructions would make sense in that section? Curve merging takes two or more curves, and approximates their combined path using a new single curve.

(as far as I can tell, those instructions are just draw commands for individual curves, not related to specifying multiple curves and having the command(s) auto-convert those to single curves?)

[tbrowder]

Well, I was thinking of my current project where I need to create a fillet of constant radius to draw an object consisting of a wheel rim with four spokes. To me, that's almost like merging two curves.

But I think I see your point. Your approach is mathematical while I am constrained by my graphics language.