And a buffer for a point would be nothing but a circle.
Yes, but that's not a polygon. If you take a line segment, and you take the set of points that at distance d, you get two half circles joined by two line segments - not a polygon either.

Anyway, the problem shouldn't be too hard. Just walk along the original polygon, and create the new 'polygon' piece by piece. For each line segment, it's easy to find the corresponding line segment. Consecutive line segments are joined by arcs, whose origin lies on the vertex of the original polygon. For convex polygons, this is all you need to do. For concave polygon, you might get self-intersections this way. But they are reasonably easy to fix by maintaining a stack of 'polygon' pieces (line segments and arcs), and either deleting the top piece(s), or intersecting with it.

In reply to Re: polygon buffering algorithms by Anonymous Monk
in thread polygon buffering algorithms by punkish

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.