Opaque set
id:
opaque-set-247-15572012
title:
Opaque set
text:
In discrete geometry, an opaque set is a system of curves or other set in the plane that blocks all lines of sight across a polygon, circle, or other shape. Opaque sets have also been called barriers, beam detectors, opaque covers, or opaque forests. Opaque sets were introduced by Stefan Mazurkiewicz in 1916, and the problem of minimizing their total length was posed by Frederick Bagemihl in 1959. For instance, visibility through a unit square can be blocked by its four boundary edges, with len
brand slug:
wiki
category slug:
encyclopedia
description:
Shape that blocks all lines of sight
original url:
https://en.wikipedia.org/wiki/Opaque_set
date created:
date modified:
2023-09-29T20:26:48Z
main entity:
{"identifier":"Q16867981","url":"https://www.wikidata.org/entity/Q16867981"}
image:
{"content_url":"https://upload.wikimedia.org/wikipedia/commons/3/38/Unit_Square_Opaque_Forest_Solutions.svg","width":405,"height":404}
fields total:
13
integrity:
15