SVG-Edit Markers Extension

The arrows extension on steroids.

public/svg-edit/editor/extensions/ext-markers.js

@@ -0,0 +1,561 @@
+/*
+ * ext-markers.js
+ *
+ * Licensed under the Apache License, Version 2
+ *
+ * Copyright(c) 2010 Will Schleter 
+ *   based on ext-arrows.js by Copyright(c) 2010 Alexis Deveria
+ *
+ * This extension provides for the addition of markers to the either end
+ * or the middle of a line, polyline, path, polygon. 
+ * 
+ * Markers may be either a graphic or arbitary text
+ * 
+ * to simplify the coding and make the implementation as robust as possible,
+ * markers are not shared - every object has its own set of markers.
+ * this relationship is maintained by a naming convention between the
+ * ids of the markers and the ids of the object
+ * 
+ * The following restrictions exist for simplicty of use and programming
+ *    objects and their markers to have the same color
+ *    marker size is fixed
+ *    text marker font, size, and attributes are fixed
+ *    an application specific attribute - se_type - is added to each marker element
+ *        to store the type of marker
+ *        
+ * TODO:
+ *    remove some of the restrictions above
+ *    add option for keeping text aligned to horizontal
+ *    add support for dimension extension lines
+ *
+ */
+
+svgEditor.addExtension("Markers", function(S) {
+	var svgcontent = S.svgcontent,
+	addElem = S.addSvgElementFromJson,
+	selElems;
+
+	var mtypes = ['start','mid','end'];
+
+	var marker_prefix = 'se_marker_';
+	var id_prefix = 'mkr_';
+		
+	// note - to add additional marker types add them below with a unique id
+	// and add the associated icon(s) to marker-icons.svg
+	// the geometry is normallized to a 100x100 box with the origin at lower left
+	// Safari did not like negative values for low left of viewBox
+	// remember that the coordinate system has +y downward
+	var marker_types = {
+		nomarker: {},  
+		leftarrow:  
+			{element:'path', attr:{d:'M0,50 L100,90 L70,50 L100,10 Z'}},
+		rightarrow:
+			{element:'path', attr:{d:'M100,50 L0,90 L30,50 L0,10 Z'}},
+		textmarker:
+			{element:'text', attr: {x:0, y:0,'stroke-width':0,'stroke':'none','font-size':75,'font-family':'serif','text-anchor':'left',
+				'xml:space': 'preserve'}},
+		forwardslash:
+			{element:'path', attr:{d:'M30,100 L70,0'}},
+		reverseslash:
+			{element:'path', attr:{d:'M30,0 L70,100'}},
+		verticalslash:
+			{element:'path', attr:{d:'M50,0 L50,100'}},
+		box:
+			{element:'path', attr:{d:'M20,20 L20,80 L80,80 L80,20 Z'}},
+		star:
+			{element:'path', attr:{d:'M10,30 L90,30 L20,90 L50,10 L80,90 Z'}},
+		xmark:
+			{element:'path', attr:{d:'M20,80 L80,20 M80,80 L20,20'}},
+		triangle:
+			{element:'path', attr:{d:'M10,80 L50,20 L80,80 Z'}},
+		circle:
+			{element:'circle', attr:{r:30, cx:50, cy:50}},			
+	}
+	
+	
+	var lang_list = {
+		"en":[
+			{id: "start_marker_list", title: "Select start marker type" },
+			{id: "mid_marker_list", title: "Select mid marker type" },
+			{id: "end_marker_list", title: "Select end marker type" },
+			{id: "nomarker", title: "No Marker" },
+			{id: "leftarrow", title: "Left Arrow" },
+			{id: "rightarrow", title: "Right Arrow" },
+			{id: "textmarker", title: "Text Marker" },
+			{id: "forwardslash", title: "Forward Slash" },
+			{id: "reverseslash", title: "Reverse Slash" },
+			{id: "verticalslash", title: "Vertical Slash" },
+			{id: "box", title: "Box" },
+			{id: "star", title: "Star" },
+			{id: "xmark", title: "X" },
+			{id: "triangle", title: "Triangle" },
+			{id: "circle", title: "Circle" },
+			{id: "leftarrow_o", title: "Open Left Arrow" },
+			{id: "rightarrow_o", title: "Open Right Arrow" },
+			{id: "box_o", title: "Open Box" },
+			{id: "star_o", title: "Open Star" },
+			{id: "triangle_o", title: "Open Triangle" },
+			{id: "circle_o", title: "Open Circle" },
+		]
+	};
+
+
+	// duplicate shapes to support unfilled (open) marker types with an _o suffix
+	$.each(['leftarrow','rightarrow','box','star','circle','triangle'],function(i,v) {
+		marker_types[v+'_o'] = marker_types[v];
+	});
+	
+	// elem = a graphic element will have an attribute like marker-start
+	// attr - marker-start, marker-mid, or marker-end
+	// returns the marker element that is linked to the graphic element
+	function getLinked(elem, attr) {
+		var str = elem.getAttribute(attr);
+		if(!str) return null;
+		var m = str.match(/\(\#(.*)\)/);
+		if(!m || m.length !== 2) {
+			return null;
+		}
+		return S.getElem(m[1]);
+	}
+
+	//toggles context tool panel off/on
+	//sets the controls with the selected element's settings
+	function showPanel(on) {
+		$('#marker_panel').toggle(on);
+
+		if(on) {
+			var el = selElems[0];
+			var val;
+			var ci;
+
+			$.each(mtypes, function(i, pos) {
+				var m=getLinked(el,"marker-"+pos);
+				var txtbox = $('#'+pos+'_marker');
+				if (!m) {
+					val='\\nomarker';
+					ci=val;
+					txtbox.hide() // hide text box
+				} else {
+					if (!m.attributes.se_type) return; // not created by this extension
+					val='\\'+m.attributes.se_type.textContent;
+					ci=val;
+					if (val=='\\textmarker') {
+						val=m.lastChild.textContent;
+						//txtbox.show(); // show text box
+					} else {
+						txtbox.hide() // hide text box
+					}
+				}
+				txtbox.val(val);				
+				setIcon(pos,ci);
+			})
+		}
+	}	
+
+	function addMarker(id, val) {
+		var txt_box_bg = '#ffffff';
+		var txt_box_border = 'none';
+		var txt_box_stroke_width = 0;
+		
+		var marker = S.getElem(id);
+
+		if (marker) return;
+
+		if (val=='' || val=='\\nomarker') return;
+
+		var el = selElems[0];		 
+		var color = el.getAttribute('stroke');
+		//NOTE: Safari didn't like a negative value in viewBox
+		//so we use a standardized 0 0 100 100
+		//with 50 50 being mapped to the marker position
+		var refX = 50;
+		var refY = 50;
+		var viewBox = "0 0 100 100";
+		var markerWidth = 5;
+		var markerHeight = 5;
+		var strokeWidth = 10;
+		if (val.substr(0,1)=='\\') se_type=val.substr(1);
+		else se_type='textmarker';
+
+		if (!marker_types[se_type]) return; // an unknown type!
+		
+ 		// create a generic marker
+		marker = addElem({
+			"element": "marker",
+			"attr": {
+			"id": id,
+			"markerUnits": "strokeWidth",
+			"orient": "auto",
+			"style": "pointer-events:none",
+			"se_type": se_type
+		}
+		});
+
+		if (se_type!='textmarker') {
+			var mel = addElem(marker_types[se_type]);
+			var fillcolor = color;
+			if (se_type.substr(-2)=='_o') fillcolor='none';
+			mel.setAttribute('fill',fillcolor);
+			mel.setAttribute('stroke',color);
+			mel.setAttribute('stroke-width',strokeWidth);
+			marker.appendChild(mel);
+		} else {
+			var text = addElem(marker_types[se_type]);
+			// have to add text to get bounding box
+			text.textContent = val;
+			var tb=text.getBBox();
+			//alert( tb.x + " " + tb.y + " " + tb.width + " " + tb.height);
+			var pad=1;
+			var bb = tb;
+			bb.x = 0;
+			bb.y = 0;
+			bb.width += pad*2;
+			bb.height += pad*2;
+			// shift text according to its size
+			text.setAttribute('x', pad);
+			text.setAttribute('y', bb.height - pad - tb.height/4); // kludge?
+			text.setAttribute('fill',color);
+			refX = bb.width/2+pad;
+			refY = bb.height/2+pad;
+			viewBox = bb.x + " " + bb.y + " " + bb.width + " " + bb.height;
+			markerWidth =bb.width/10;
+			markerHeight = bb.height/10;
+
+			var box = addElem({
+				"element": "rect",
+				"attr": {
+				"x": bb.x,
+				"y": bb.y,
+				"width": bb.width,
+				"height": bb.height,
+				"fill": txt_box_bg,
+				"stroke": txt_box_border,
+				"stroke-width": txt_box_stroke_width
+			}
+			});
+			marker.setAttribute("orient",0);
+			marker.appendChild(box);
+			marker.appendChild(text);
+		} 
+
+		marker.setAttribute("viewBox",viewBox);
+		marker.setAttribute("markerWidth", markerWidth);
+		marker.setAttribute("markerHeight", markerHeight);
+		marker.setAttribute("refX", refX);
+		marker.setAttribute("refY", refY);
+		S.findDefs().appendChild(marker);
+
+		return marker;
+	}
+
+
+	function setMarker() {
+		var poslist={'start_marker':'start','mid_marker':'mid','end_marker':'end'};
+		var pos = poslist[this.id];
+		var marker_name = 'marker-'+pos;
+		var val = this.value;
+		var el = selElems[0];
+		var marker = getLinked(el, marker_name);
+		if (marker) $(marker).remove();
+		el.removeAttribute(marker_name);
+		if (val=='') val='\\nomarker';
+		if (val=='\\nomarker') {
+			setIcon(pos,val);
+			return;
+		}
+		// Set marker on element
+		var id = marker_prefix + pos + '_' + el.id;
+		addMarker(id, val);
+		svgCanvas.changeSelectedAttribute(marker_name, "url(#" + id + ")");
+		if (el.tagName == "line" && pos=='mid') el=convertline(el);
+		S.call("changed", selElems);
+		setIcon(pos,val);
+	}
+
+	function convertline(elem) {
+		// this routine came from the connectors extension
+		// it is needed because midpoint markers don't work with line elements
+		if (!(elem.tagName == "line")) return elem;
+
+		// Convert to polyline to accept mid-arrow
+
+		var x1 = elem.getAttribute('x1')-0;
+		var x2 = elem.getAttribute('x2')-0;
+		var y1 = elem.getAttribute('y1')-0;
+		var y2 = elem.getAttribute('y2')-0;
+		var id = elem.id;
+
+		var mid_pt = (' '+((x1+x2)/2)+','+((y1+y2)/2) + ' ');
+		var pline = addElem({
+			"element": "polyline",
+			"attr": {
+			"points": (x1+','+y1+ mid_pt +x2+','+y2),
+			"stroke": elem.getAttribute('stroke'),
+			"stroke-width": elem.getAttribute('stroke-width'),
+			"fill": "none",
+			"opacity": elem.getAttribute('opacity') || 1
+		}
+		});
+		$.each(mtypes, function(i, pos) { // get any existing marker definitions
+			var nam = 'marker-'+pos;
+			var m = elem.getAttribute(nam);
+			if (m) pline.setAttribute(nam,elem.getAttribute(nam));
+		});
+		$(elem).after(pline).remove();
+		svgCanvas.clearSelection();
+		pline.id = id;
+		svgCanvas.addToSelection([pline]);
+		return pline;
+	}
+
+	// called when the main system modifies an object
+	// this routine changes the associated markers to be the same color
+	function colorChanged(elem) {
+		var color = elem.getAttribute('stroke');
+
+		$.each(mtypes, function(i, pos) {
+			var marker = getLinked(elem, 'marker-'+pos);
+			if (!marker) return;
+			if (!marker.attributes.se_type) return; //not created by this extension
+			var ch = marker.lastElementChild;
+			if (!ch) return;
+			var curfill = ch.getAttribute("fill");
+			var curstroke = ch.getAttribute("stroke")
+			if (curfill && curfill!='none') ch.setAttribute("fill",color);
+			if (curstroke && curstroke!='none') ch.setAttribute("stroke",color);
+		});
+	}
+
+	// called when the main system creates or modifies an object
+	// primary purpose is create new markers for cloned objects
+	function updateReferences(el) {
+		$.each(mtypes, function (i,pos) {
+			var id = marker_prefix + pos + '_' + el.id;
+			var marker_name = 'marker-'+pos;
+			var marker = getLinked(el, marker_name);
+			if (!marker || !marker.attributes.se_type) return; //not created by this extension
+			var url = el.getAttribute(marker_name);
+			if (url) {
+				var len = el.id.length;
+				var linkid = url.substr(-len-1,len);
+				if (el.id != linkid) {
+					var val = $('#'+pos+'_marker').attr('value');
+					addMarker(id, val);
+					svgCanvas.changeSelectedAttribute(marker_name, "url(#" + id + ")");
+					if (el.tagName == "line" && pos=='mid') el=convertline(el);
+					S.call("changed", selElems);
+				}
+			}
+		});
+	}
+
+	// simulate a change event a text box that stores the current element's marker type
+	function triggerTextEntry(pos,val) {
+		$('#'+pos+'_marker').val(val);
+		$('#'+pos+'_marker').change();
+		var txtbox = $('#'+pos+'_marker');
+		//if (val.substr(0,1)=='\\') txtbox.hide();
+		//else txtbox.show();
+	}
+	
+	function setIcon(pos,id) {
+		if (id.substr(0,1)!='\\') id='\\textmarker'
+		var ci = '#'+id_prefix+pos+'_'+id.substr(1);
+		svgEditor.setIcon('#cur_' + pos +'_marker_list', $(ci).children());
+		$(ci).addClass('current').siblings().removeClass('current');
+	}
+		
+	function setMarkerSet(obj) {
+		var parts = this.id.split('_');
+		var set = parts[2];
+		switch (set) {
+		case 'off':
+			triggerTextEntry('start','\\nomarker');
+			triggerTextEntry('mid','\\nomarker');
+			triggerTextEntry('end','\\nomarker');
+			break;
+		case 'dimension':
+			triggerTextEntry('start','\\leftarrow');
+			triggerTextEntry('end','\\rightarrow');
+			showTextPrompt('mid');
+			break;
+		case 'label':
+			triggerTextEntry('mid','\\nomarker');
+			triggerTextEntry('end','\\rightarrow');
+			showTextPrompt('start');
+			break;
+		}
+	}
+		
+	function showTextPrompt(pos) {
+		var def = $('#'+pos+'_marker').val();
+		if (def.substr(0,1)=='\\') def='';
+		$.prompt('Enter text for ' + pos + ' marker', def , function(txt) { if (txt) triggerTextEntry(pos,txt); });
+	}
+	
+	// callback function for a toolbar button click
+	function setArrowFromButton(obj) {
+		
+		var parts = this.id.split('_');
+		var pos = parts[1];
+		var val = parts[2];
+		if (parts[3]) val+='_'+parts[3];
+		
+		if (val!='textmarker') {
+			triggerTextEntry(pos,'\\'+val);
+		} else {
+			showTextPrompt(pos);
+		}
+	}
+	
+	function getTitle(lang,id) {
+		var list = lang_list[lang];
+		for (var i in list) {
+			if (list[i].id==id) return list[i].title;
+		}
+		return id;
+	}
+	
+	
+	// build the toolbar button array from the marker definitions
+	// TODO: need to incorporate language specific titles
+	function buildButtonList() {
+		var buttons=[];
+		var i=0;
+/*
+		buttons.push({
+			id:id_prefix + 'markers_off',
+			title:'Turn off all markers',
+			type:'context',
+			events: { 'click': setMarkerSet },
+			panel: 'marker_panel'
+		});
+		buttons.push({
+			id:id_prefix + 'markers_dimension',
+			title:'Dimension',
+			type:'context',
+			events: { 'click': setMarkerSet },
+			panel: 'marker_panel'
+		});
+		buttons.push({
+			id:id_prefix + 'markers_label',
+			title:'Label',
+			type:'context',
+			events: { 'click': setMarkerSet },
+			panel: 'marker_panel'
+		});
+*/
+		$.each(mtypes,function(k,pos) {
+			var listname = pos + "_marker_list";
+			var def = true;
+		$.each(marker_types,function(id,v) {
+			var title = getTitle('en',id);
+			buttons.push({
+					id:id_prefix + pos + "_" + id,
+					svgicon:id,
+					title:title,
+					type:'context',
+					events: { 'click': setArrowFromButton },
+					panel:'marker_panel',
+					list: listname,
+					isDefault: def
+			});
+			def = false;
+		});
+		});
+		return buttons;
+	}
+
+	return {
+		name: "Markers",
+		svgicons: "extensions/markers-icons.xml",
+		buttons: buildButtonList(),
+		context_tools: [
+		   {
+			type: "input",
+			panel: "marker_panel",
+			title: "Start marker",
+			id: "start_marker",
+			label: "s",
+			size: 3,
+			events: { change: setMarker }
+		},{
+			type: "button-select",
+			panel: "marker_panel",
+			title: getTitle('en','start_marker_list'),
+			id: "start_marker_list",
+			events: { change: setArrowFromButton }
+		},{
+			type: "input",
+			panel: "marker_panel",
+			title: "Middle marker",
+			id: "mid_marker",
+			label: "m",
+			defval: "",
+			size: 3,
+			events: { change: setMarker }
+		},{
+			type: "button-select",
+			panel: "marker_panel",
+			title: getTitle('en','mid_marker_list'),
+			id: "mid_marker_list",
+			events: { change: setArrowFromButton }
+		},{
+			type: "input",
+			panel: "marker_panel",
+			title: "End marker",
+			id: "end_marker",
+			label: "e",
+			size: 3,
+			events: { change: setMarker }
+		},{
+			type: "button-select",
+			panel: "marker_panel",
+			title: getTitle('en','end_marker_list'),
+			id: "end_marker_list",
+			events: { change: setArrowFromButton }
+		} ],
+		callback: function() {
+			$('#marker_panel').hide();
+		},
+		addLangData: function(lang) {
+			return { data: lang_list[lang] };
+		},
+
+	selectedChanged: function(opts) {
+		// Use this to update the current selected elements
+		//console.log('selectChanged',opts);
+		selElems = opts.elems;
+
+		var i = selElems.length;
+		var marker_elems = ['line','path','polyline','polygon'];
+
+		while(i--) {
+			var elem = selElems[i];
+			if(elem && $.inArray(elem.tagName, marker_elems) != -1) {
+				if(opts.selectedElement && !opts.multiselected) {
+					showPanel(true);
+				} else {
+					showPanel(false);
+				}
+			} else {
+				showPanel(false);
+			}
+		}
+	},
+
+	elementChanged: function(opts) {		
+		//console.log('elementChanged',opts);
+		var elem = opts.elems[0];
+		if(elem && (
+				elem.getAttribute("marker-start") ||
+				elem.getAttribute("marker-mid") ||
+				elem.getAttribute("marker-end")
+		)) {
+			colorChanged(elem);
+			updateReferences(elem);
+		}
+		changing_flag = false;
+	}
+	};
+});

public/svg-edit/editor/extensions/markers-icons.xml

@@ -0,0 +1,120 @@
+<svg xmlns="http://www.w3.org/2000/svg">
+    <!-- Created with SVG-edit - http://svg-edit.googlecode.com/ -->
+    <g id="nomarker">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="#ff7f00" d="m-50,0l100,0"/>
+        </svg>
+    </g>
+    <g id="leftarrow">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="#ff7f00" d="m-50,0l100,40l-30,-40l30,-40z"/>
+        </svg>
+    </g>
+    <g id="rightarrow">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="#ff7f00" d="m50,0l-100,40l30,-40l-30,-40z"/>
+        </svg>
+    </g>
+    <g id="leftarrow_o">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="none" d="m-50,0l100,40l-30,-40l30,-40z"/>
+        </svg>
+    </g>
+    <g id="rightarrow_o">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="none" d="m50,0l-100,40l30,-40l-30,-40z"/>
+        </svg>
+    </g>
+    <g id="forwardslash">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="none" d="m-20,50l40,-100"/>
+        </svg>
+    </g>
+    <g id="reverseslash">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="none" d="m-20,-50l40,100"/>
+        </svg>
+    </g>
+    <g id="verticalslash">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="none" d="m0,-50l0,100"/>
+        </svg>
+    </g>
+    <g id="circle">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <circle stroke-width="10" stroke="#ff7f00" fill="#ff7f00" cy="0" cx="0" r="30"/>
+        </svg>
+    </g>
+    <g id="circle_o">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <circle stroke-width="10" stroke="#ff7f00" fill="none" cy="0" cx="0" r="30"/>
+        </svg>
+    </g>
+    <g id="xmark">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="#ff7f00" d="m-30,30l60,-60m0,60l-60,-60"/>
+        </svg>
+    </g>
+    <g id="box">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="#ff7f00" d="m-30,-30l0,60l60,0l0,-60z"/>
+        </svg>
+    </g>
+    <g id="star">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="#ff7f00" d="m-40,-20l80,0l-70,60l30,-80l30,80z"/>
+        </svg>
+    </g>
+    <g id="box_o">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="none" d="m-30,-30l0,60l60,0l0,-60z"/>
+        </svg>
+    </g>
+    <g id="star_o">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="none" d="m-40,-20l80,0l-70,60l30,-80l30,80z"/>
+        </svg>
+    </g>
+     <g id="triangle_o">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="none" d="M-30,30 L0,-30 L30,30 Z"/>
+        </svg>
+    </g>
+     <g id="triangle">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+            <path stroke-width="10" stroke="#ff7f00" fill="#ff7f00" d="M-30,30 L0,-30 L30,30 Z"/>
+        </svg>
+    </g>
+   <g id="textmarker">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+			<text xml:space="preserve" text-anchor="middle" font-family="serif" font-size="120"  y="40" x="0" stroke-width="0" stroke="#ff7f00" fill="#ff7f00">T</text>	
+        </svg>
+    </g>
+   <g id="textmarker">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+			<text xml:space="preserve" text-anchor="middle" font-family="serif" font-size="120"  y="40" x="0" stroke-width="0" stroke="#ff7f00" fill="#ff7f00">T</text>	
+        </svg>
+    </g>
+	<g id="mkr_markers_off">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+		   <line y2="0" x2="50" y1="0" x1="-50" stroke-width="5" stroke="#ff7f00" fill="none"/>
+       </svg>
+    </g>
+	<g id="mkr_markers_dimension">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+ 		   <line y2="0" x2="40" y1="0" x1="20" stroke-width="5" stroke="#ff7f00" fill="none"/>
+		   <line y2="0" x2="-40" y1="0" x1="-20" stroke-width="5" stroke="#ff7f00" fill="none"/>
+		   <text text-anchor="middle" font-family="serif" font-size="80"  y="20" x="0" stroke-width="0" stroke="#ff7f00" fill="#ff7f00">T</text>
+           <path stroke-width="5" stroke="#ff7f00" fill="#ff7f00" d="M-50,0 L-30,-15 L-30,15 Z"/>
+           <path stroke-width="5" stroke="#ff7f00" fill="#ff7f00" d="M50,0 L30,-15 L30,15 Z"/>
+ 		</svg>
+    </g>
+   	<g id="mkr_markers_label">
+        <svg viewBox="-60 -60 120 120" xmlns="http://www.w3.org/2000/svg">
+  		   <line y2="0" x2="40" y1="0" x1="-20" stroke-width="5" stroke="#ff7f00" fill="none"/>
+		   <text text-anchor="middle" font-family="serif" font-size="80"  y="20" x="-40" stroke-width="0" stroke="#ff7f00" fill="#ff7f00">T</text>
+           <path stroke-width="5" stroke="#ff7f00" fill="#ff7f00" d="M50,0 L30,-15 L30,15 Z"/>
+        </svg>
+    </g>
+	<g id="svg_eof"/>
+</svg>

public/svg-edit/editor/svg-editor.js

@@ -45,7 +45,7 @@
 				imgPath: 'images/',
 				langPath: 'locale/',
 				extPath: 'extensions/',
-				extensions: ['ext-arrows.js', 'ext-connector.js', 'ext-eyedropper.js', 'ext-itex.js'],
+				extensions: ['ext-markers.js','ext-connector.js', 'ext-eyedropper.js', 'ext-itex.js'],
 				initTool: 'select',
 				wireframe: false
 			},
@@ -776,6 +776,8 @@
 					}
 				}
 		
+				var btn_selects = [];
+		
 				if(ext.context_tools) {
 					$.each(ext.context_tools, function(i, tool) {
 						// Add select tool
@@ -813,7 +815,24 @@
 								$(sel).bind(evt, func);
 							});
 							break;
+						case 'button-select': 
+							var html = '<div id="' + tool.id + '" class="dropdown toolset" title="' + tool.title + '">'
+								+ '<div id="cur_' + tool.id + '" class="icon_label"></div><button></button></div>';
 							
+							var list = $('<ul id="' + tool.id + '_opts"></ul>').appendTo('#option_lists');
+							
+							// Creates the tool, hides & adds it, returns the select element
+							var dropdown = $(html).appendTo(panel).children();
+							
+							btn_selects.push({
+								elem: ('#' + tool.id),
+								list: ('#' + tool.id + '_opts'),
+								title: tool.title,
+								callback: tool.events.change,
+								cur: ('#cur_' + tool.id)
+							});
+
+							break;
 						case 'input':
 							var html = '<label' + cont_id + '>'
 								+ '<span id="' + tool.id + '_label">' 
@@ -865,7 +884,8 @@
 							icon = $('<img src="' + btn.icon + '">');
 						} else {
 							fallback_obj[id] = btn.icon;
-							placement_obj['#' + id] = btn.id;
+							var svgicon = btn.svgicon?btn.svgicon:btn.id;
+							placement_obj['#' + id] = svgicon;
 						}
 						
 						var cls, parent;
@@ -885,13 +905,22 @@
 							break;
 						}
 						
-						var button = $('<div/>')
+						var button = $(btn.list?'<li/>':'<div/>')
 							.attr("id", id)
 							.attr("title", btn.title)
 							.addClass(cls);
-						if(!btn.includeWith) {
+						if(!btn.includeWith && !btn.list) {
 							button.appendTo(parent);
-						} else {
+						} else if(btn.list) {
+							// Add button to list
+							button.addClass('push_button');
+							$('#' + btn.list + '_opts').append(button);
+ 							if(btn.isDefault) {
+ 								$('#cur_' + btn.list).append(button.children().clone());
+ 								var svgicon = btn.svgicon?btn.svgicon:btn.id;
+	 							placement_obj['#cur_' + btn.list] = svgicon;
+ 							}
+						} else if(btn.includeWith) {
 							// Add to flyout menu / make flyout menu
 							var opts = btn.includeWith;
 							// opts.button, default, position
@@ -948,6 +977,7 @@
 							button.append(icon);
 						}
 						
+						if(!btn.list) {
 							// Add given events to button
 							$.each(btn.events, function(name, func) {
 								if(name == "click") {
@@ -972,10 +1002,16 @@
 									button.bind(name, func);
 								}
 							});
+						}
 						
 						setupFlyouts(holders);
 					});
 					
+					$.each(btn_selects, function() {
+						addAltDropDown(this.elem, this.list, this.callback, {seticon: true}); 
+					});
+
+					
 					$.svgIcons(svgicons, {
 						w:24, h:24,
 						id_match: false,
@@ -1700,7 +1736,14 @@
 				if(dropUp) {
 					$(elem).addClass('dropup');
 				}
-				list.find('li').bind('mouseup', callback);
+				list.find('li').bind('mouseup', function() {
+					if(opts.seticon) {
+						setIcon('#cur_' + button[0].id , $(this).children());
+						$(this).addClass('current').siblings().removeClass('current');
+					}
+					callback.apply(this, arguments);
+
+				});
 				
 				$(window).mouseup(function(evt) {
 					if(!on_button) {
@@ -1712,7 +1755,6 @@
 				});
 				
 				var height = list.height();
-				
 				$(elem).bind('mousedown',function() {
 					var off = $(elem).offset();
 					if(dropUp) {
@@ -2294,8 +2336,8 @@
 				svgCanvas.setBackground(color, url);
 			}
 			
-			var setIcon = function(elem, icon_id, forcedSize) {
+			var setIcon = Editor.setIcon = function(elem, icon_id, forcedSize) {
-				var icon = $.getSvgIcon(icon_id).clone();
+				var icon = (typeof icon_id == 'string') ? $.getSvgIcon(icon_id).clone() : icon_id.clone();
 				$(elem).empty().append(icon);
 				if(forcedSize) {
 					var obj = {};
@@ -3471,7 +3513,7 @@
 				updateCanvas(true);
 // 			});
 			
-		//	var revnums = "svg-editor.js ($Rev: 1577 $) ";
+		//	var revnums = "svg-editor.js ($Rev: 1586 $) ";
 		//	revnums += svgCanvas.getVersion();
 		//	$('#copyright')[0].setAttribute("title", revnums);
 		

public/svg-edit/editor/svgcanvas.js

@@ -221,7 +221,10 @@ function ChangeElementCommand(elem, attrs, text) {
 					this.elem.removeAttribute(attr);
 				}
 			}
+			
 			if (attr == "transform") { bChangedTransform = true; }
+			else if (attr == "stdDeviation") { canvas.setBlurOffsets(this.elem.parentNode, this.newValues[attr]); }
+			
 		}
 		// relocate rotational transform, if necessary
 		if(!bChangedTransform) {
@@ -250,6 +253,8 @@ function ChangeElementCommand(elem, attrs, text) {
 				if (attr == "#text") this.elem.textContent = this.oldValues[attr];
 				else if (attr == "#href") this.elem.setAttributeNS(xlinkns, "xlink:href", this.oldValues[attr]);
 				else this.elem.setAttribute(attr, this.oldValues[attr]);
+				
+				if (attr == "stdDeviation") canvas.setBlurOffsets(this.elem.parentNode, this.oldValues[attr]);
 			}
 			else {
 				if (attr == "#text") this.elem.textContent = "";
@@ -1439,6 +1444,7 @@ function BatchCommand(text) {
 							node.setAttribute(nv[0],nv[1]);
 						}
 					}
+					node.removeAttribute('style');
 				}
 			}
 			
@@ -2421,8 +2427,10 @@ function BatchCommand(text) {
 		// else, it's a non-group
 		else {
 			// FIXME: box might be null for some elements (<metadata> etc), need to handle this
-			var box = canvas.getBBox(selected),
+			var box = canvas.getBBox(selected);
-				oldcenter = {x: box.x+box.width/2, y: box.y+box.height/2},
+			if(!box) return null;
+			
+			var oldcenter = {x: box.x+box.width/2, y: box.y+box.height/2},
 				newcenter = transformPoint(box.x+box.width/2, box.y+box.height/2,
 								transformListToTransform(tlist).matrix),
 				m = svgroot.createSVGMatrix(),
@@ -2647,8 +2655,7 @@ function BatchCommand(text) {
 		var i = elemsToAdd.length;
 		while (i--) {
 			var elem = elemsToAdd[i];
-			// we ignore any selectors
+			if (!elem || !this.getBBox(elem)) continue;
-			if (!elem || elem.id.substr(0,13) == "selectorGrip_" || !this.getBBox(elem)) continue;
 			// if it's not already there, add it
 			if (selectedElements.indexOf(elem) == -1) {
 				selectedElements[j] = elem;
@@ -2922,6 +2929,39 @@ function BatchCommand(text) {
 				aabox: {x:minx, y:miny, width:(maxx-minx), height:(maxy-miny)} };
 	};
 	
+	var getMouseTarget = function(evt) {
+		if (evt == null) {
+			return null;
+		}
+		var mouse_target = evt.target;
+		
+		// if it was a <use>, Opera and WebKit return the SVGElementInstance
+		if (mouse_target.correspondingUseElement)
+		
+		mouse_target = mouse_target.correspondingUseElement;
+		// for foreign content, go up until we find the foreignObject
+		// WebKit browsers set the mouse target to the svgcanvas div 
+		if ($.inArray(mouse_target.namespaceURI, [mathns, htmlns]) != -1 && 
+			mouse_target.id != "svgcanvas") 
+		{
+			while (mouse_target.nodeName != "foreignObject") {
+				mouse_target = mouse_target.parentNode;
+			}
+		}
+		
+		// go up until we hit a child of a layer
+		while (mouse_target.parentNode.parentNode.tagName == "g") {
+			mouse_target = mouse_target.parentNode;
+		}
+		// Webkit bubbles the mouse event all the way up to the div, so we
+		// set the mouse_target to the svgroot like the other browsers
+		if (mouse_target.nodeName.toLowerCase() == "div") {
+			mouse_target = svgroot;
+		}
+		
+		return mouse_target;
+	};
+
 	// Mouse events
 	(function() {
 		
@@ -2955,34 +2995,11 @@ function BatchCommand(text) {
 			
 			var x = mouse_x / current_zoom,
 				y = mouse_y / current_zoom,
-				mouse_target = evt.target;
+				mouse_target = getMouseTarget(evt);
 			
 			start_x = x;
 			start_y = y;
 	
-			// if it was a <use>, Opera and WebKit return the SVGElementInstance
-			if (mouse_target.correspondingUseElement)
-				mouse_target = mouse_target.correspondingUseElement;
-	
-			// for foreign content, go up until we find the foreignObject
-			// WebKit browsers set the mouse target to the svgcanvas div 
-			if ($.inArray(mouse_target.namespaceURI, [mathns, htmlns]) != -1 && 
-				mouse_target.id != "svgcanvas") 
-			{
-				while (mouse_target.nodeName != "foreignObject") {
-					mouse_target = mouse_target.parentNode;
-				}
-			}
-			
-			// go up until we hit a child of a layer
-			while (mouse_target.parentNode.parentNode.tagName == "g") {
-				mouse_target = mouse_target.parentNode;
-			}
-			// Webkit bubbles the mouse event all the way up to the div, so we
-			// set the mouse_target to the svgroot like the other browsers
-			if (mouse_target.nodeName.toLowerCase() == "div") {
-				mouse_target = svgroot;
-			}
 			// if it is a selector grip, then it must be a single element selected, 
 			// set the mouse_target to that and update the mode to rotate/resize
 			if (mouse_target.parentNode == selectorManager.selectorParentGroup && selectedElements[0] != null) {
@@ -3262,6 +3279,7 @@ function BatchCommand(text) {
 			});
 		};
 
+		
 		// in this function we do not record any state changes yet (but we do update
 		// any elements that are still being created, moved or resized on the canvas)
 		// TODO: svgcanvas should just retain a reference to the image being dragged instead
@@ -3292,10 +3310,7 @@ function BatchCommand(text) {
 						var dx = x - start_x;
 						var dy = y - start_y;
 						
-						if(evt.shiftKey) { // restrict to movement up/down/left/right (WRS)
+						if(evt.shiftKey) { var xya = snapToAngle(start_x,start_y,x,y); x=xya.x; y=xya.y; }
-							if (Math.abs(dx)>Math.abs(dy)) dy=0;
-							else dx=0; 
-							}
 
 						if (dx != 0 || dy != 0) {
 							var len = selectedElements.length;
@@ -3471,16 +3486,7 @@ function BatchCommand(text) {
 					var x2 = x;
 					var y2 = y;					
 
-					if(evt.shiftKey) {
+					if(evt.shiftKey) { var xya=Utils.snapToAngle(start_x,start_y,x2,y2); x2=xya.x; y2=xya.y; }
-						var snap = Math.PI/4; // 45 degrees
-						var diff_x = x - start_x;
-						var diff_y = y - start_y;
-						var angle = Math.atan2(diff_y,diff_x);
-						var dist = Math.sqrt(diff_x * diff_x + diff_y * diff_y);
-						var snapangle= Math.round(angle/snap)*snap;
-						x2 = start_x + dist*Math.cos(snapangle);	
-						y2 = start_y + dist*Math.sin(snapangle);	
-					}
 					
 					shape.setAttributeNS(null, "x2", x2);
 					shape.setAttributeNS(null, "y2", y2);
@@ -3551,9 +3557,11 @@ function BatchCommand(text) {
 					x *= current_zoom;
 					y *= current_zoom;
 					
-					if(evt.shiftKey) { // restrict path segments to horizontal/vertical (WRS)
+					if(evt.shiftKey) {
-						if (Math.abs(start_x-x)>Math.abs(start_y-y)) {y=start_y; mouse_y=y;}
+						var x1 = path.dragging?path.dragging[0]:start_x;
-						else {x=start_x; mouse_x=x;}
+						var y1 = path.dragging?path.dragging[1]:start_y;
+					    var xya=Utils.snapToAngle(x1,y1,x,y);
+					    x=xya.x; y=xya.y;
 					}
 					
 					if(rubberBox && rubberBox.getAttribute('display') != 'none') {
@@ -3565,7 +3573,7 @@ function BatchCommand(text) {
 						},100);
 					}
 					
-					pathActions.mouseMove(mouse_x, mouse_y);
+					pathActions.mouseMove(x, y);
 					
 					break;
 				case "textedit":
@@ -3941,7 +3949,7 @@ function BatchCommand(text) {
 	}());
 
 	var textActions = canvas.textActions = function() {
-		var curtext;
+		var curtext, current_text;
 		var textinput;
 		var cursor;
 		var selblock;
@@ -4164,11 +4172,12 @@ function BatchCommand(text) {
 
 		return {
 			select: function(target, x, y) {
-				if (curtext == target) {
+				if (current_text == target) {
+					curtext = target;
 					textActions.toEditMode(x, y);
 				} // going into pathedit mode
 				else {
-					curtext = target;
+					current_text = target;
 				}	
 			},
 			start: function(elem) {
@@ -4262,6 +4271,7 @@ function BatchCommand(text) {
 				$(textinput).blur(hideCursor);
 			},
 			clear: function() {
+				current_text = null;
 				if(current_mode == "textedit") {
 					textActions.toSelectMode();
 				}
@@ -5516,17 +5526,15 @@ function BatchCommand(text) {
 						// else, create a new point, append to pts array, update path element
 						else {
 							// Checks if current target or parents are #svgcontent
-							if(!$.contains(container, evt.target)) {
+							if(!$.contains(container, getMouseTarget(evt))) {
 								// Clicked outside canvas, so don't make point
+								console.log("Clicked outside canvas");
 								return false;
 							}
 
 							var lastx = current_path_pts[len-2], lasty = current_path_pts[len-1];
 
-							if (evt.shiftKey) { // restrict to horizonontal/vertical (WRS)
+							if(evt.shiftKey) { var xya=Utils.snapToAngle(lastx,lasty,x,y); x=xya.x; y=xya.y; }
-								if (Math.abs(x-lastx)>Math.abs(y-lasty)) y=lasty;
-								else x=lastx;
-							}
 
 							// we store absolute values in our path points array for easy checking above
 							current_path_pts.push(x);
@@ -5660,6 +5668,7 @@ function BatchCommand(text) {
 			},
 			
 			clear: function(remove) {
+				current_path = null;
 				if (current_mode == "path" && current_path_pts.length > 0) {
 					var elem = getElem(getId());
 					$(getElem("path_stretch_line")).remove();
@@ -6660,8 +6669,13 @@ function BatchCommand(text) {
 				else {
 					var ts = "scale(" + (canvash/3)/vb[2] + ")";
 				}
-				if (vb[0] != 0 || vb[1] != 0)
+				
-					ts = "translate(" + (-vb[0]) + "," + (-vb[1]) + ") " + ts;
+				// Hack to make recalculateDimensions understand how to scale
+				ts = "translate(0) " + ts + " translate(0)";
+				
+				// TODO: Find way to add this in a recalculateDimensions-parsable way
+// 				if (vb[0] != 0 || vb[1] != 0)
+// 					ts = "translate(" + (-vb[0]) + "," + (-vb[1]) + ") " + ts;
 
 				// add all children of the imported <svg> to the <g> we create
 				var g = svgdoc.createElementNS(svgns, "g");
@@ -6750,6 +6764,7 @@ function BatchCommand(text) {
     	    	}
     	    	
     	    	// now give the g itself a new id
+    	    	
 				g.id = getNextId();
 				// manually increment obj_num because our cloned elements are not in the DOM yet
 				obj_num++;
@@ -6783,7 +6798,7 @@ function BatchCommand(text) {
 			
 			// recalculate dimensions on the top-level children so that unnecessary transforms
 			// are removed
-			walkTreePost(importedNode, function(n){try{recalculateDimensions(n)}catch(e){console.log(e)}});
+			walkTreePost(svgcontent, function(n){try{recalculateDimensions(n)}catch(e){console.log(e)}});
 			
 			
 			batchCmd.addSubCommand(new InsertElementCommand(svgcontent));
@@ -7723,6 +7738,7 @@ function BatchCommand(text) {
 					canvas.changeSelectedAttributeNoUndo("filter", 'url(#' + selectedElements[0].id + '_blur)');
 				}
 				canvas.changeSelectedAttributeNoUndo("stdDeviation", val, [filter.firstChild]);
+				canvas.setBlurOffsets(filter, val);
 			}
 		}
 		
@@ -7734,6 +7750,23 @@ function BatchCommand(text) {
 			filter = null;
 		}
 	
+		canvas.setBlurOffsets = function(filter, stdDev) {
+			if(stdDev > 3) {
+				// TODO: Create algorithm here where size is based on expected blur
+				assignAttributes(filter, {
+					x: '-50%',
+					y: '-50%',
+					width: '200%',
+					height: '200%',
+				}, 100);
+			} else {
+				filter.removeAttribute('x');
+				filter.removeAttribute('y');
+				filter.removeAttribute('width');
+				filter.removeAttribute('height');
+			}
+		}
+	
 		canvas.setBlur = function(val, complete) {
 			if(cur_command) {
 				finishChange();
@@ -7786,20 +7819,7 @@ function BatchCommand(text) {
 				
 				batchCmd.addSubCommand(new ChangeElementCommand(elem, changes));
 				
-				if(val > 3) {
+				canvas.setBlurOffsets(filter, val);
-					// TODO: Create algorithm here where size is based on expected blur
-					assignAttributes(filter, {
-						x: '-50%',
-						y: '-50%',
-						width: '200%',
-						height: '200%',
-					}, 100);
-				} else {
-					filter.removeAttribute('x');
-					filter.removeAttribute('y');
-					filter.removeAttribute('width');
-					filter.removeAttribute('height');
-				}
 			}
 			
 			cur_command = batchCmd;
@@ -8188,7 +8208,7 @@ function BatchCommand(text) {
 			}
 			
 			// only allow the transform/opacity attribute to change on <g> elements, slightly hacky
-			if (elem.tagName == "g" && (attr != "transform" && attr != "opacity")) continue;
+			if (elem.tagName == "g" && $.inArray(attr, ['transform', 'opacity', 'filter']) !== -1);
 			var oldval = attr == "#text" ? elem.textContent : elem.getAttribute(attr);
 			if (oldval == null)  oldval = "";
 			if (oldval != String(newValue)) {
@@ -8374,11 +8394,12 @@ function BatchCommand(text) {
 			// and then for each child, if they do not have the attribute (or the value is 'inherit')
 			// then set the child's attribute
 			
-			// TODO: get the group's opacity and propagate it down to the children (multiply it
-			// by the child's opacity (or 1.0)
-			
 			var i = 0;
 			var gangle = canvas.getRotationAngle(g);
+			
+			var gattrs = $(g).attr(['filter', 'opacity']);
+			var gfilter, gblur;
+			
 			while (g.firstChild) {
 				var elem = g.firstChild;
 				var oldNextSibling = elem.nextSibling;
@@ -8386,6 +8407,49 @@ function BatchCommand(text) {
 				children[i++] = elem = parent.insertBefore(elem, anchor);
 				batchCmd.addSubCommand(new MoveElementCommand(elem, oldNextSibling, oldParent));
 				
+				if(gattrs.opacity !== null && gattrs.opacity !== 1) {
+					var c_opac = elem.getAttribute('opacity') || 1;
+					var new_opac = Math.round((elem.getAttribute('opacity') || 1) * gattrs.opacity * 100)/100;
+					this.changeSelectedAttribute('opacity', new_opac, [elem]);
+				}
+
+				if(gattrs.filter) {
+					var cblur = this.getBlur(elem);
+					var orig_cblur = cblur;
+					if(!gblur) gblur = this.getBlur(g);
+					if(cblur) {
+						// Is this formula correct?
+						cblur = (gblur-0) + (cblur-0);
+					} else if(cblur === 0) {
+						cblur = gblur;
+					}
+					
+					// If child has no current filter, get group's filter or clone it.
+					if(!orig_cblur) {
+						// Set group's filter to use first child's ID
+						if(!gfilter) {
+							gfilter = getElem(getUrlFromAttr(gattrs.filter).substr(1));
+						} else {
+							// Clone the group's filter
+							gfilter = copyElem(gfilter);
+							findDefs().appendChild(gfilter);
+						}
+					} else {
+						gfilter = getElem(getUrlFromAttr(elem.getAttribute('filter')).substr(1));
+					}
+
+					// Change this in future for different filters
+					var suffix = (gfilter.firstChild.tagName === 'feGaussianBlur')?'blur':'filter'; 
+					gfilter.id = elem.id + '_' + suffix;
+					this.changeSelectedAttribute('filter', 'url(#' + gfilter.id + ')', [elem]);
+					
+					// Update blur value 
+					if(cblur) {
+						this.changeSelectedAttribute('stdDeviation', cblur, [gfilter.firstChild]);
+						canvas.setBlurOffsets(gfilter, cblur);
+					}
+				}
+				
 				var chtlist = canvas.getTransformList(elem);
 				
 				if (glist.numberOfItems) {
@@ -8463,6 +8527,7 @@ function BatchCommand(text) {
 				}
 			}
 
+			
 			// remove transform and make it undo-able
 			if (xform) {
 				var changes = {};
@@ -9089,7 +9154,7 @@ function BatchCommand(text) {
 	// Function: getVersion
 	// Returns a string which describes the revision number of SvgCanvas.
 	this.getVersion = function() {
-		return "svgcanvas.js ($Rev: 1576 $)";
+		return "svgcanvas.js ($Rev: 1586 $)";
 	};
 	
 	this.setUiStrings = function(strs) {
@@ -9139,6 +9204,7 @@ function BatchCommand(text) {
 			getElem: getElem,
 			getId: getId,
 			getIntersectionList: getIntersectionList,
+			getMouseTarget: getMouseTarget,
 			getNextId: getNextId,
 			getPathBBox: getPathBBox,
 			getUrlFromAttr: getUrlFromAttr,
@@ -9360,6 +9426,19 @@ var Utils = {
 			(r2.y+r2.height) > r1.y;
 	},
 
+	"snapToAngle": function(x1,y1,x2,y2) {
+		var snap = Math.PI/4; // 45 degrees
+		var dx = x2 - x1;
+		var dy = y2 - y1;
+		var angle = Math.atan2(dy,dx);
+		var dist = Math.sqrt(dx * dx + dy * dy);
+		var snapangle= Math.round(angle/snap)*snap;
+		var x = x1 + dist*Math.cos(snapangle);	
+		var y = y1 + dist*Math.sin(snapangle);
+		//console.log(x1,y1,x2,y2,x,y,angle)
+		return {x:x, y:y, a:snapangle};
+	},
+	
 	// found this function http://groups.google.com/group/jquery-dev/browse_thread/thread/c6d11387c580a77f
 	"text2xml": function(sXML) {
 		// NOTE: I'd like to use jQuery for this, but jQuery makes all tags uppercase