adding instructions to chord.txt

data/chord.txt

@@ -1,7 +1,7 @@
 // chord diagram from http://mbostock.github.com/d3/ex/chord.html
 // colors from the twilight theme: http://bit.ly/wufWv1
 
-// click the pulsing red numbers and hold down the Ctrl key!
+// click the pulsing red numbers and hold down the Control or Command key!
 
 var chord = d3.layout.chord()
   .padding(0.05)

js/jquery.hotkeys.js

@@ -0,0 +1,105 @@
+/*
+ * jQuery Hotkeys Plugin
+ * Copyright 2010, John Resig
+ * Dual licensed under the MIT or GPL Version 2 licenses.
+ *
+ * Based upon the plugin by Tzury Bar Yochay:
+ * http://github.com/tzuryby/hotkeys
+ *
+ * Original idea by:
+ * Binny V A, http://www.openjs.com/scripts/events/keyboard_shortcuts/
+*/
+
+(function(jQuery){
+
+	jQuery.hotkeys = {
+		version: "0.8",
+
+		specialKeys: {
+			8: "backspace", 9: "tab", 13: "return", 16: "shift", 17: "ctrl", 18: "alt", 19: "pause",
+			20: "capslock", 27: "esc", 32: "space", 33: "pageup", 34: "pagedown", 35: "end", 36: "home",
+			37: "left", 38: "up", 39: "right", 40: "down", 45: "insert", 46: "del",
+			96: "0", 97: "1", 98: "2", 99: "3", 100: "4", 101: "5", 102: "6", 103: "7",
+			104: "8", 105: "9", 106: "*", 107: "+", 109: "-", 110: ".", 111 : "/",
+			112: "f1", 113: "f2", 114: "f3", 115: "f4", 116: "f5", 117: "f6", 118: "f7", 119: "f8",
+			120: "f9", 121: "f10", 122: "f11", 123: "f12", 144: "numlock", 145: "scroll", 188: ",", 190: ".",
+			191: "/", 224: "meta"
+		},
+
+		shiftNums: {
+			"`": "~", "1": "!", "2": "@", "3": "#", "4": "$", "5": "%", "6": "^", "7": "&",
+			"8": "*", "9": "(", "0": ")", "-": "_", "=": "+", ";": ": ", "'": "\"", ",": "<",
+			".": ">",  "/": "?",  "\\": "|"
+		}
+	};
+
+	function keyHandler( handleObj ) {
+
+		var origHandler = handleObj.handler,
+			//use namespace as keys so it works with event delegation as well
+			//will also allow removing listeners of a specific key combination
+			//and support data objects
+			keys = (handleObj.namespace || "").toLowerCase().split(" ");
+
+		//no need to modify handler if no keys specified
+		if (!keys.length) {
+			return;
+		}
+
+		handleObj.handler = function( event ) {
+			// Don't fire in text-accepting inputs that we didn't directly bind to
+			// important to note that $.fn.prop is only available on jquery 1.6+
+			if ( this !== event.target && (/textarea|select/i.test( event.target.nodeName ) ||
+				event.target.type === "text" || $(event.target).prop('contenteditable') == 'true' )) {
+				return;
+			}
+
+			// Keypress represents characters, not special keys
+			var special = event.type !== "keypress" && jQuery.hotkeys.specialKeys[ event.which ],
+				character = String.fromCharCode( event.which ).toLowerCase(),
+				key, modif = "", possible = {};
+
+			// check combinations (alt|ctrl|shift+anything)
+			if ( event.altKey && special !== "alt" ) {
+				modif += "alt_";
+			}
+
+			if ( event.ctrlKey && special !== "ctrl" ) {
+				modif += "ctrl_";
+			}
+
+			// TODO: Need to make sure this works consistently across platforms
+			if ( event.metaKey && !event.ctrlKey && special !== "meta" ) {
+				modif += "meta_";
+			}
+
+			if ( event.shiftKey && special !== "shift" ) {
+				modif += "shift_";
+			}
+
+			if ( special ) {
+				possible[ modif + special ] = true;
+
+			} else {
+				possible[ modif + character ] = true;
+				possible[ modif + jQuery.hotkeys.shiftNums[ character ] ] = true;
+
+				// "$" can be triggered as "Shift+4" or "Shift+$" or just "$"
+				if ( modif === "shift_" ) {
+					possible[ jQuery.hotkeys.shiftNums[ character ] ] = true;
+				}
+			}
+
+			for ( var i = 0, l = keys.length; i < l; i++ ) {
+				if ( possible[ keys[i] ] ) {
+					return origHandler.apply( this, arguments );
+				}
+			}
+		};
+	}
+
+	jQuery.each([ "keydown", "keyup", "keypress" ], function() {
+		jQuery.event.special[ this ] = { add: keyHandler };
+	});
+
+})( jQuery );