Hi Nathan. I do a deeper look.
///////////////////////////////////////////////////////////////////// El mar, 13-05-2014 a las 03:40 +1000, Nathan Hurst escribió: 1) to my old astigmatic eyes the tangents do not look like they are
quite matched, are you sure you have the tangent code correct. This is especially noticable when you are filleting a curve rather than a line.
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When I convert to paths a filleting the result curvature is a path of one segment, start and end nodes of this are tangent to front-back curves, and thsi sttart and end nodes are also handled as tangent for the inkscape UI.
Maybe the problem is how far is the tangent handle from a node, but there isn`t a perfect way to determine, it depends from case. I use the nearest point to the tangent from a point placed at a half distance from the real knot filleting to the original cusp node.
Here are some pics about how it works: http://sta.sh/28yrjqkdiw1
////////////////////////////////////////////////////////////////////// 2) can you add fillets with smooth curvature variation (e.g. cornu
spiral, spiro, and I recall there being a 2geom toy that demonstrated something like that).
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I see about it in power stroke code, I realy do the code but finaly removed, think isnt interesting in one curve path, because it increase the nuber of nodes of the resulting path because you need to pass the cubic values of the handles as points, because the incoming and outgoing curve need to be unchanged.
This is my opinion but if anybody want to tell me about, i could change ;)
Thanks Nathan for the feedback.