{"id":658,"date":"2008-02-02T16:11:45","date_gmt":"2008-02-02T15:11:45","guid":{"rendered":"http:\/\/www.lumen.nu\/rekveld\/wp\/?p=658"},"modified":"2019-08-24T21:44:45","modified_gmt":"2019-08-24T20:44:45","slug":"the-return-of-the-boids","status":"publish","type":"post","link":"https:\/\/www.joostrekveld.net\/?p=658","title":{"rendered":"the return of the boids"},"content":{"rendered":"<p><img decoding=\"async\" id=\"image659\" src=\"https:\/\/www.joostrekveld.net\/wp\/wp-content\/uploads\/2008\/02\/starlings2.jpg\" alt=\"starlings2.jpg\" \/><br \/>\n<em>image H.Chat\u00e9, F.Raynaud, STARFLAG Project, CNR-INFM <\/em><\/p>\n<p>In 1986 Craig Reynolds devised the <a href=\"http:\/\/www.red3d.com\/cwr\/boids\/\" target=\"_blank\" rel=\"noopener noreferrer\">boids<\/a>-algorithm, based on a model of the interactions in flocks, herds or schools of animals. The magic of the boids algorithm is that complex overall patterns emerge from local interactions between agents. Reynolds writes: &#8220;flocking requires that it reacts only to flockmates within a certain small neighborhood around itself. The neighborhood is characterized by a <em>distance<\/em> (measured from the center of the boid) and an <em>angle,<\/em> measured from the boid&#8217;s direction of flight. Flockmates outside this local neighborhood are ignored.&#8221;<br \/>\nRecently, european <a href=\"http:\/\/angel.elte.hu\/starling\/\" target=\"_blank\" rel=\"noopener noreferrer\">researchers<\/a> have <a href=\"http:\/\/xxx.lanl.gov\/abs\/0709.1916\" target=\"_blank\" rel=\"noopener noreferrer\">found<\/a> that starlings do not interact with all neighbours within a certain range, but rather with a fixed number (six or seven) of neighbours, irrespective of their distance. This makes the flocking more robust when there are big changes in density. Please update your algorithms !<br \/>\n(via <a href=\"http:\/\/www.greythumb.org\/blog\/index.php?\/archives\/278-Update-to-Boids-algorithm.html\" target=\"_blank\" rel=\"noopener noreferrer\">greythumb<\/a>, nice article <a href=\"http:\/\/ptonline.aip.org\/journals\/doc\/PHTOAD-ft\/vol_60\/iss_10\/28_1.shtml\" target=\"_blank\" rel=\"noopener noreferrer\">here<\/a>)<\/p>\n","protected":false},"excerpt":{"rendered":"<p>image H.Chat\u00e9, F.Raynaud, STARFLAG Project, CNR-INFM In 1986 Craig Reynolds devised the boids-algorithm, based on a model of the interactions in flocks, herds or schools of animals. The magic of the boids algorithm is that complex overall patterns emerge from local interactions between agents. Reynolds writes: &#8220;flocking requires that it reacts only to flockmates within &hellip; <a href=\"https:\/\/www.joostrekveld.net\/?p=658\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">the return of the boids<\/span> <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":659,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8,10],"tags":[],"class_list":["post-658","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-umwelt","category-websites"],"_links":{"self":[{"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=\/wp\/v2\/posts\/658","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=658"}],"version-history":[{"count":1,"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=\/wp\/v2\/posts\/658\/revisions"}],"predecessor-version":[{"id":2518,"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=\/wp\/v2\/posts\/658\/revisions\/2518"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=\/wp\/v2\/media\/659"}],"wp:attachment":[{"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=658"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=658"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.joostrekveld.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=658"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}