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that contains the other, then there are no common lines of support, while if each of two shapes consists of a pair of small disks at opposite corners of a square then there may be as many as 16 common lines of support.
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The notion of supporting line is also discussed for planar shapes. In this case a supporting line may be defined as a line which has common points with the boundary of the shape, but not with its interior.
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exists at a given point, then it is the unique supporting line at this point, if it does not separate the curve.
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that are separated by a positive distance, then they necessarily have exactly four common lines of support, the
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The notion of a supporting line to a planar curve or convex shape can be generalized to n dimension as a
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of the two convex hulls. Two of these lines of support separate the two shapes, and are called
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There can be many supporting lines for a curve at a given point. When a
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Animation of parallel supporting lines around a
Reuleaux triangle.
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If two bounded connected planar shapes have disjoint
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164:"Encyclopedia of Distances", by
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61:. In other words,
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22:Reuleaux triangle
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166:Michel M. Deza
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192:Geometry
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37:geometry
130:annulus
90:tangent
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67:closed
48:curve
46:of a
39:, a
35:In
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78:L
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63:C
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44:L
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