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plotting - Drawing the Pursuit curves


I was reading this post on Filling Space with Pursuit Polygons. I didn't really see where the filling was, but found it quite interesting.


Then I saw these pursuit curves.



enter image description here


They seem to have used a different logarithm. For example looking at the square, by tweaking the code from the previous code, I got this


With[{data = {{0, 0}, {1, 0}, {1, 1}, {0, 1}, {0, 0}}},  Graphics[{Table[{Scale[       Rotate[Line[data], 90/11*x Degree], {x, x}]}, {x, 0, 11}]}]]

enter image description here


Both picture has 11 sets of squares. With a bit trial and error, I got as close as possible by changing the angles.


How can I get the identical pictures?


And these ones below, which looks more challenging. enter image description here enter image description here



Answer



In this answer of mine I wrote a simple function that will draw the curve you are after, given an arbitrary polygon:



g[x_] := Fold[Append[#1, BSplineFunction[#1[[#2]], SplineDegree -> 1][.1]] &, x, Partition[Range[200], 2, 1]]

For example, given the triangle


ListPlot[Prepend[{{0, 0}, {1, 0}, {1/2, Sqrt[3]/2}}, {1/2, Sqrt[3]/2}], AspectRatio -> 1, Joined -> True, PlotRange -> All]

enter image description here


we get


ListPlot[Prepend[g@{{0, 0}, {1, 0}, {1/2, Sqrt[3]/2}}, {1/2, Sqrt[3]/2}], AspectRatio -> 1, Joined -> True, PlotRange -> All]

enter image description here



With this, it is just a matter of combining triangles to generate all the figures in the OP.


For example, given the hexagon


ListPlot[{Prepend[{{0, 0}, {1, 0}, {1/2, Sqrt[3]/2}}, {1/2, Sqrt[3]/2}], Prepend[{{1, 0}, {2, 0}, {3/2, Sqrt[3]/2}}, {3/2, Sqrt[3]/2}], Prepend[{{0, 0}, {1, 0}, {1/2, -(Sqrt[3]/2)}}, {1/2, -(Sqrt[3]/2)}], Prepend[{{1, 0}, {2, 0}, {3/2, -(Sqrt[3]/2)}}, {3/2, -(Sqrt[3]/2)}], Prepend[{{1/2, Sqrt[3]/2}, {3/2, Sqrt[3]/2}, {1, 0}}, {1, 0}], Prepend[{{1/2, -(Sqrt[3]/2)}, {3/2, -(Sqrt[3]/2)}, {1, 0}}, {1, 0}]}, AspectRatio -> 1, Joined -> True, PlotRange -> All]

enter image description here


we get


ListPlot[{Prepend[g@{{0, 0}, {1, 0}, {1/2, Sqrt[3]/2}}, {1/2, Sqrt[3]/2}], Prepend[g@{{1, 0}, {2, 0}, {3/2, Sqrt[3]/2}}, {3/2, Sqrt[3]/2}], Prepend[g@{{0, 0}, {1, 0}, {1/2, -(Sqrt[3]/2)}}, {1/2, -(Sqrt[3]/2)}], Prepend[g@{{1, 0}, {2, 0}, {3/2, -(Sqrt[3]/2)}}, {3/2, -(Sqrt[3]/2)}], Prepend[g@{{1/2, Sqrt[3]/2}, {3/2, Sqrt[3]/2}, {1, 0}}, {1, 0}], Prepend[g@{{1/2, -(Sqrt[3]/2)}, {3/2, -(Sqrt[3]/2)}, {1, 0}}, {1, 0}]}, AspectRatio -> 1, Joined -> True, PlotRange -> All]

enter image description here


Tweaking the parameters and using black lines, we get



enter image description here


which is almost identical to the figure in the OP. Similarly,


enter image description here


while the rest of figures are left to the reader.


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