[{"data":1,"prerenderedAt":273},["ShallowReactive",2],{"project-12639612":3},{"id":4,"name":5,"line":6,"line_source":7,"title":8,"url":9,"domain":5,"maker":10,"posted_at":11,"year":12,"points":13,"comments":14,"rank_in_year":15,"shown_in_year":16,"top":17,"tier":18,"category":19,"subcategory":20,"format":21,"keywords":22,"reception":27,"sentiment":28,"stance_mix":29,"scored_comments":34,"aspects":35,"strip":41,"post_text":43,"what":44,"said":47,"maker_in_thread":141,"shape":148,"grid":153,"attempts":235,"same_week":236,"maker_shows":142,"maker_hidden":265,"reader_version":266,"card":267},"12639612","christophercliff.com","Dijkstra’s algorithm in the web browser with OpenStreetMap","title","Show HN: Dijkstra’s algorithm in the web browser with OpenStreetMap","https:\u002F\u002Fchristophercliff.com\u002Fdijkstra\u002F","ctcliff",1475616268,2016,158,34,204,2264,10,"notable","dev_tools","algorithm visualization","web_app",[23,24,25,26],"dijkstra","openstreetmap","shortest path","routing","curious",-0.032,{"positive":30,"neutral":31,"mixed":32,"critical":33},3,8,0,4,15,{"docs":36,"performance":38,"design":39,"idea":40},{"positive":32,"critical":37},1,{"positive":32,"critical":32},{"positive":32,"critical":37},{"positive":37,"critical":32},[37,37,30,30,30,30,32,32,32,32,32,32,32,32,32,32,32,32,32,32,30,32,37,32,30,42,42,32,30,37,42,30,32,32],5,null,{"problem":43,"audience":43,"pricing":43,"motivation":43,"time_to_build":43,"stack":45,"openness":46,"stage":46,"team_size":46},[],"unknown",{"praise":48,"objections":61,"requests":94,"questions":107,"alternatives":122},[49],{"value":50,"source":51,"evidence":52},"Interesting and well presented demo","commenter",[53,57],{"id":54,"by":55,"text":56},"12641209","mgalka","Very cool project. Great presentation.",{"id":58,"by":59,"text":60},"12647777","sapien13","Nice work. I think we are doing somethings correlated. https:\u002F\u002Fnews.ycombinator.com\u002Fitem?id=12647348",[62,73,83],{"value":63,"source":51,"evidence":64},"Not open source",[65,69],{"id":66,"by":67,"text":68},"12640466","_RPM","Interesting. It'd be pretty cooler if this was free software though.",{"id":70,"by":71,"text":72},"12639805","d33","How about an open source version?",{"value":74,"source":51,"evidence":75},"Rendering of the path is slow, and the map is zoomed oddly in background tabs",[76,79],{"id":77,"by":10,"text":78},"12639859","I haven't, but even at this size the rendering is quite a bit slower than the calculation. For example, the delay on reload is almost entirely from rendering the shortest path…",{"id":80,"by":81,"text":82},"12640511","jlarocco","Bug report: if I open this in a background tab the map is zoomed in very close at a weird spot near the middle and it's confusing what is being demonstrated.",{"value":84,"source":51,"evidence":85},"Lacks instructions for dropping pins and displaying the route",[86,90],{"id":87,"by":88,"text":89},"12640378","mastazi","Are there any instructions? It took me a long while to figure out how to drop pins (the placeholder text says you have to press Enter, but you actually need to use the mouse),…",{"id":91,"by":92,"text":93},"12642745","alex_minimax","I've got the two markers but no route being displayed, is there a third step (firefox and chrome)?",[95,100],{"value":96,"source":51,"evidence":97},"Open source the code",[98,99],{"id":70,"by":71,"text":72},{"id":66,"by":67,"text":68},{"value":101,"source":51,"evidence":102},"Animate the search to show the computation",[103],{"id":104,"by":105,"text":106},"12641763","janci","It would be more interesting, if the path is animated and shows the computation of the algorithm, not only the result.",[108,115],{"value":109,"source":51,"evidence":110},"Whether A* performs better than Dijkstra on larger maps",[111],{"id":112,"by":113,"text":114},"12639778","ddlutz","Have you tried this with A* and seen any performance differences? This is very fast in the browser with a small map, but I imagine with a much larger map the difference would be…",{"value":116,"source":51,"evidence":117},"How contraction hierarchies preprocessing works",[118],{"id":119,"by":120,"text":121},"12642439","amelius","> but the pre-processing time is very long Could you elaborate on why the preprocessing time is long? I didn't study contraction hierarchies, but to me it seems that computing…",[123,134],{"value":124,"source":51,"evidence":125},"OSRM routing engine",[126,130],{"id":127,"by":128,"text":129},"12640162","teraflop","Anyone who's interested in this might want to check out the OSRM project, which uses a much more complex routing algorithm to efficiently find paths through the entire OSM graph,…",{"id":131,"by":132,"text":133},"12641599","danpat","I'm one of the OSRM devs. To expand on this comment a bit - OSRM still uses Dijkstra, so if you understand that, you already basically understand what OSRM does. What OSRM does…",{"value":135,"source":51,"evidence":136},"Pathfinding visualization with OSM data built for an AI class",[137],{"id":138,"by":139,"text":140},"12641009","kevan","Related: A few friends and I built a similar visualization for pathfinding algorithms with OSM data for an AI class: http:\u002F\u002Fwww.kevanahlquist.com\u002Fosm_pathfinding\u002F It shows how…",{"comments":142,"answered":142,"key":143},2,[144,145],{"id":77,"text":78},{"id":146,"text":147},"12639807","The geographic rendering APIs tend to be incompatible with the graphing algorithms and data structures. It's better to optimize your data on the server for algorithmic simplicity…",{"commenters":149,"max_depth":150,"maker_replies":142,"first_comment_mins":151,"lifespan_hours":152},25,7,13,24,[154,156,158,161,165,168,169,173,176,180,181,183,186,188,191,193,195,197,198,201,203,205,206,208,210,211,214,218,220,222,224,225,230,233],[127,32,37,155,128,32],"project\u002Fcritical\u002Fnone",[87,32,37,157,88,32],"project\u002Fcritical\u002Fdocs",[159,32,30,160,132,32],"12640936","project\u002Fneutral\u002Fdocs",[162,32,30,163,164,32],"12640974","project\u002Fneutral\u002Fnone","kornish",[166,32,30,160,167,32],"12641034","maxerickson",[91,32,30,160,92,32],[170,32,32,171,172,32],"12640450","other\u002Fneutral\u002Fnone","Doctor_Fegg",[174,32,32,171,175,32],"12640658","cabalamat",[177,32,32,178,179,32],"12640777","commenter\u002Fneutral\u002Fnone","fermuch",[131,32,32,171,132,32],[119,32,32,182,120,32],"other\u002Fneutral\u002Fperformance",[184,32,32,178,185,32],"12642635","lorenzhs",[187,32,32,178,120,32],"12642864",[189,32,32,178,190,32],"12642917","adrianN",[192,32,32,178,185,32],"12642966",[194,32,32,178,185,32],"12642961",[196,32,32,178,132,32],"12644853",[138,37,32,171,139,32],[199,37,32,171,200,32],"12641869","grawlinson",[202,37,32,171,139,32],"12641939",[112,142,30,204,113,32],"project\u002Fneutral\u002Fperformance",[77,142,32,204,10,37],[80,30,37,207,81,32],"project\u002Fcritical\u002Fdesign",[209,33,32,171,167,32],"12639741",[70,42,30,163,71,32],[58,212,42,213,59,32],6,"maker\u002Fpositive\u002Fnone",[215,150,42,216,217,32],"12639695","maker\u002Fpositive\u002Fidea","soperj",[146,150,32,219,10,37],"maker\u002Fneutral\u002Fnone",[104,31,30,221,105,32],"project\u002Fneutral\u002Fdesign",[66,223,37,155,67,32],9,[54,17,42,213,55,32],[226,227,30,228,229,32],"12642274",11,"project\u002Fneutral\u002Fidea","liotier",[231,227,32,178,232,32],"12642717","EllipticCurve",[234,227,32,178,229,32],"12643244",[],[237,242,246,251,256,260],{"id":238,"name":239,"points":240,"category":241},"12612246","Wave function collapse",1226,"ai",{"id":243,"name":244,"points":245,"category":19},"12621680","Ascii to SVG",416,{"id":247,"name":248,"points":249,"category":250},"12646083","Mastodon",364,"infrastructure",{"id":252,"name":253,"points":254,"category":255},"12640851","Cypht",110,"productivity",{"id":257,"name":258,"points":259,"category":241},"12619694","Graph Convolutional Networks",106,{"id":261,"name":262,"points":263,"category":264},"12621655","Forgiva",97,"security_privacy",false,"v2",{"id":268,"name":5,"line":6,"ai":265,"cat":19,"year":12,"points":13,"comments":14,"rec":27,"s":269,"top":17,"kw":270,"maker":10,"domain":5,"tier":18,"attempts":32,"strip":271,"url":9,"mix":272,"praise":50,"objection":63,"sub":20},12639612,-0.03,[23,24,25,26],"1133330000000000000030103550315300",[30,31,32,33],1794036548279]