{"id":12665,"date":"2021-11-15T18:32:19","date_gmt":"2021-11-15T23:32:19","guid":{"rendered":"https:\/\/carleton.ca\/scs\/?page_id=12665"},"modified":"2026-06-02T14:59:26","modified_gmt":"2026-06-02T18:59:26","slug":"tr-131-an-efficient-window-based-system-based-on-constraints","status":"publish","type":"page","link":"https:\/\/carleton.ca\/scs\/research\/scs-technical-reports\/technical-reports-1988\/tr-131-an-efficient-window-based-system-based-on-constraints\/","title":{"rendered":"TR-131: An Efficient Window Based System Based on Constraints"},"content":{"rendered":"\n<section class=\"w-screen px-6 cu-section cu-section--white ml-offset-center md:px-8 lg:px-14\">\n    <div class=\"space-y-6 cu-max-w-child-5xl  md:space-y-10 cu-prose-first-last\">\n\n            <div class=\"cu-textmedia flex flex-col lg:flex-row mx-auto gap-6 md:gap-10 my-6 md:my-12 first:mt-0 max-w-5xl\">\n        <div class=\"justify-start cu-textmedia-content cu-prose-first-last\" style=\"flex: 0 0 100%;\">\n            <header class=\"font-light prose-xl cu-pageheader md:prose-2xl cu-component-updated cu-prose-first-last\">\n                                    <h1 class=\"cu-prose-first-last font-semibold !mt-2 mb-4 md:mb-6 relative after:absolute after:h-px after:bottom-0 after:bg-cu-red after:left-px text-3xl md:text-4xl lg:text-5xl lg:leading-[3.5rem] pb-5 after:w-10 text-cu-black-700 not-prose\">\n                        TR-131: An Efficient Window Based System Based on Constraints\n                    <\/h1>\n                \n                                \n                            <\/header>\n\n                    <\/div>\n\n            <\/div>\n\n    <\/div>\n<\/section>\n\n<p>Carleton University<br>\n<a href=\"https:\/\/carleton.ca\/scs\/research\/scs-technical-reports\/technical-reports-1988\/\">Technical Report<\/a> <strong>TR-131<\/strong><br>\nMarch 1988<\/p>\n\n\n\n<h2 id=\"an-efficient-window-based-system-based-on-constraints\" class=\"wp-block-heading tr_t1\">An Efficient Window Based System Based on Constraints<\/h2>\n\n\n\n<div class=\"tr_t3\">\n<div class=\"tr_t3\">\n<div class=\"tr_t3\">Danny Epstein &amp; Wilf LaLonde<\/div>\n<\/div>\n<\/div>\n\n\n\n<div>\n<h3>Abstract<\/h3>\n<p>We describe the design of an efficient constrant-based window system for Smalltalk. This window system permits the specification of windows by constraining the subwindows to satisfy relationships from a very small number of primitive prioritized constraints. In fact, only three classes of constraints are supported, one of which is implicit and unavailable for general use. The system extends the current Smalltalk system by eliminating some of its existing inadequacies and by permitting the integration of both fixed-sized and scalable subwindows in the same window. A goal of the design is to produce a system with real-time response that is fast enough to be substituted for the existing design. A prototype with response times of less than 1\/4 a second has been implemented to demonstrate the notions; alternative constraint satisfaction solution techniques are being experimented with to speed it up even further.<\/p>\n<\/div>\n\n\n\n<p><a href=\"https:\/\/carleton.ca\/scs\/wp-content\/uploads\/sites\/260\/tr-131.pdf\">TR-131.pdf<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Carleton University Technical Report TR-131 March 1988 An Efficient Window Based System Based on Constraints Danny Epstein &amp; Wilf LaLonde Abstract We describe the design of an efficient constrant-based window system for Smalltalk. This window system permits the specification of windows by constraining the subwindows to satisfy relationships from a very small number of primitive [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":11829,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"_cu_dining_location_slug":"","footnotes":"","_links_to":"","_links_to_target":""},"cu_page_type":[],"class_list":["post-12665","page","type-page","status-publish","hentry"],"acf":{"cu_post_thumbnail":false},"_links":{"self":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/12665","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/comments?post=12665"}],"version-history":[{"count":2,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/12665\/revisions"}],"predecessor-version":[{"id":12672,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/12665\/revisions\/12672"}],"up":[{"embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/pages\/11829"}],"wp:attachment":[{"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/media?parent=12665"}],"wp:term":[{"taxonomy":"cu_page_type","embeddable":true,"href":"https:\/\/carleton.ca\/scs\/wp-json\/wp\/v2\/cu_page_type?post=12665"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}