<!doctype html> <title>CodeMirror: B-Tree visualization</title> <meta charset="utf-8"/> <link rel=stylesheet href="../doc/docs.css"> <link rel="stylesheet" href="../lib/codemirror.css"> <script src="../lib/codemirror.js"></script> <style type="text/css"> .lineblock { display: inline-block; margin: 1px; height: 5px; } .CodeMirror {border: 1px solid #aaa; height: 400px} </style> <div id=nav> <a href="http://codemirror.net"><img id=logo src="../doc/logo.png"></a> <ul> <li><a href="../index.html">Home</a> <li><a href="../doc/manual.html">Manual</a> <li><a href="https://github.com/marijnh/codemirror">Code</a> </ul> <ul> <li><a class=active href="#">B-Tree visualization</a> </ul> </div> <article> <h2>B-Tree visualization</h2> <form><textarea id="code" name="code">type here, see a summary of the document b-tree below</textarea></form> </div> <div style="display: inline-block; height: 402px; overflow-y: auto" id="output"></div> </div> <script id="me"> var editor = CodeMirror.fromTextArea(document.getElementById("code"), { lineNumbers: true, lineWrapping: true }); var updateTimeout; editor.on("change", function(cm) { clearTimeout(updateTimeout); updateTimeout = setTimeout(updateVisual, 200); }); updateVisual(); function updateVisual() { var out = document.getElementById("output"); out.innerHTML = ""; function drawTree(out, node) { if (node.lines) { out.appendChild(document.createElement("div")).innerHTML = "<b>leaf</b>: " + node.lines.length + " lines, " + Math.round(node.height) + " px"; var lines = out.appendChild(document.createElement("div")); lines.style.lineHeight = "6px"; lines.style.marginLeft = "10px"; for (var i = 0; i < node.lines.length; ++i) { var line = node.lines[i], lineElt = lines.appendChild(document.createElement("div")); lineElt.className = "lineblock"; var gray = Math.min(line.text.length * 3, 230), col = gray.toString(16); if (col.length == 1) col = "0" + col; lineElt.style.background = "#" + col + col + col; lineElt.style.width = Math.max(Math.round(line.height / 3), 1) + "px"; } } else { out.appendChild(document.createElement("div")).innerHTML = "<b>node</b>: " + node.size + " lines, " + Math.round(node.height) + " px"; var sub = out.appendChild(document.createElement("div")); sub.style.paddingLeft = "20px"; for (var i = 0; i < node.children.length; ++i) drawTree(sub, node.children[i]); } } drawTree(out, editor.getDoc()); } function fillEditor() { var sc = document.getElementById("me"); var doc = (sc.textContent || sc.innerText || sc.innerHTML).replace(/^\s*/, "") + "\n"; doc += doc; doc += doc; doc += doc; doc += doc; doc += doc; doc += doc; editor.setValue(doc); } </script> <p><button onclick="fillEditor()">Add a lot of content</button></p> </article>