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Edges running on top of each other in mxGraph

I am setting up the mxGraph like this:
model = new mxGraphModel();
// Tell the model to manage cell ids for us
model.isCreateIds();
graph = new mxGraph(container, model);
var graphMgr = new GraphManager(graph);
var edgeMgr = new EdgeManager();
// Configure mxGraph properties, methods, and event handlers
graphMgr.configure();
// Create style sheet
graphMgr.defineStyles();
// Initialize the layout managers
graphMgr.defineLayout(model);
// Get the main parent for the graph
var parent = graph.getDefaultParent();
var parallelEdges = new mxParallelEdgeLayout(graph);
parallelEdges.execute(parent);
That is the initial setup. I just added the mxParallelEdgeLayout thing because I have found that that is supposed to prevent edges from running on top of each other and overlap. What I mean by overlapping and running on top of each other:
I am using Orthogonal edge styling.
If this is not how you prevent this (using mxParallelEdgeLayout), then is there a way that mxGraph prevents this kind of thing? And if mxParallelEdgeLayout is the way to go, does anyone know why it is not accepting my execution of the layout?

Have you tried using the spacing variable?
var parallelEdges = new mxParallelEdgeLayout(graph);
parallelEdges.spacing = 20;

Create js animation of a horizontal spritesheet

I have gone through the docs and sample only to be lost in outdated docs. Apparently there is no samples for the latest version of createjs.
I need to smooth scroll a horizontal spritesheet. So that the middle of images are shown before the new image is entirely in the "window". So the place in the page doesnt move only what is displayed from the single column horizontal spritesheet is different. And we do not switch between images we scroll up and down.
I am at my wits end with this.
this.sprite = new createjs.BitmapAnimation(spriteSheet);
that line gives an error
not a constructor
this.sprite = createjs.BitmapAnimation(spriteSheet);
gives an error
not a function
here is the sprite sheet
https://github.com/nydehi/asp.net-mvc-example-invoicing-app/blob/master/screenshots/1.png
i am doing this now and no error but nothing is displayed.
<script type="text/javascript" src="createjs-2014.12.12.min.js"></script>
<script>
function init() {
var data = {
images: ["1.png"],
frames: {width:15, height:20},
animations: {
stand:0,
run:[1,5],
jump:[6,8,"run"]
}
};
var spriteSheet = new createjs.SpriteSheet(data);
var animation = new createjs.Sprite(spriteSheet, "run");
var stage = new createjs.Stage("demoCanvas");
stage.addChild(animation);
animation.gotoAndPlay("run"); //walking from left to right
stage.update();
}
</script>

You're probably using a more recent version of CreateJS (around version 0.8.2) which no longer has a BitmapAnimation class on it.
Older versions (0.6.0) had it, but it was most likely replaced by the SpriteSheet class.
Check here for the most recent documentation.

The earlier comments about BitmapAnimation being deprecated long ago are right. Your updated code sample looks fine otherwise.
I think you are just missing something to update the stage when contents change. Your sample just has the one update, but because your image is loaded using a string path, it is not ready yet when you call stage.update().
Any time contents change, you need to tell the stage to refresh. Typically, this is manually controlled when contents change, or constantly using the Ticker.
createjs.Ticker.on("tick", function(event) {
// Other updates
// Update the stage
stage.update(event);
});
// Or a handy shortcut if you don't need to do anything else on tick:
createjs.Ticker.on("tick", stage);

html 5 canvas: using draw image in game makes loop very slow

i am making a game based on draw images and clear it every some part of second.
i started with:
var peng = new Image();
and then:
peng.onload = function() {
context.drawImage(peng, pengXPosition, pengYPosition, pengWidth, pengHight);
};
and in the loop:
var i=0;
function pengMoveRight(){ i++;if(i==1){peng.src = 'images/1.png';}else if(i==2)
{peng.src = 'images/2.png';} else if(i==3){peng.src = 'images/3.png';}else if(i==4){
peng.src = 'images/4.png';}else if(i==5){peng.src = 'images/5.png';}else if(i==6){
peng.src = 'images/6.png';i-=6;}}
when i run it it works well on IE but on chrome and mozilla it`s too slow and the character is about to disappear .. i used setinterval(); once and window.requestAnimationFrame(); once and both of them cause the same problem.
what should i do to make it smooth move?
here is the full script http://mark-tec.com/custom%20game/

Instead of changing the source, try to create several Image objects instead. That way, the drawImage call can always use a pre-loaded image.

You need to preload all the images or use the sprite method (all images packed into a single sprite) in order to avoid the initial delay caused by the image loading only when it's needed.
However, after that initial problem, your example should run fine once all the images are cached.

Dynamically "unload" a Processing JS sketch from canvas

I'm using some javascript to allow users to dynamically load a sketch on click to a canvas element using:
Processing.loadSketchFromSources('canvas_id', ['sketch.pde']);
If I call Processing.loadSketchFromSources(...) a second (or third...) time, it loads a second (or third...) .pde file onto the canvas, which is what I would expect.
I'd like for the user to be able to click another link to load a different sketch, effectively unloading the previous one. Is there a method I can call (or a technique I can use) to check if Processing has another sketch running, and if so, tell it to unload it first?
Is there some sort of Processing.unloadSketch() method I'm overlooking? I could simply drop the canvas DOM object and recreate it, but that (1) seems like using a hammer when I need a needle, and (2) it results in a screen-flicker that I'd like to avoid.
I'm no JS expert, but I've done my best to look through the processing.js source to see what other functions may exist, but I'm hitting a wall. I thought perhaps I could look at Processing.Sketches.length to see if something is loaded already, but simply pop'ing it off the array doesn't seem to work (didn't think it would).
I'm using ProcessingJS 1.3.6.

In case someone else comes looking for the solution, here's what I did that worked. Note that this was placed inside a closure (not included here for brevity) -- hence the this.launch = function(), blah blah blah... YMMV.
/**
* Launches a specific sketch. Assumes files are stored in
* the ./sketches subdirectory, and your canvas is named g_sketch_canvas
* #param {String} item The name of the file (no extension)
* #param {Array} sketchlist Array of sketches to choose from
* #returns true
* #type Boolean
*/
this.launch = function (item, sketchlist) {
var cvs = document.getElementById('g_sketch_canvas'),
ctx = cvs.getContext('2d');
if ($.inArray(item, sketchlist) !== -1) {
// Unload the Processing script
if (Processing.instances.length > 0) {
// There should only be one, so no need to loop
Processing.instances[0].exit();
// If you may have more than one, then use this loop:
for (i=0; i < Processing.instances.length; (i++)) {
// Processing.instances[i].exit();
//}
}
// Clear the context
ctx.setTransform(1, 0, 0, 1, 0, 0);
ctx.clearRect(0, 0, cvs.width, cvs.height);
// Now, load the new Processing script
Processing.loadSketchFromSources(cvs, ['sketches/' + item + '.pde']);
}
return true;
};

I'm not familiar with Processing.js, but the example code from the site has this:
var canvas = document.getElementById("canvas1");
// attaching the sketchProc function to the canvas
var p = new Processing(canvas, sketchProc);
// p.exit(); to detach it
So in your case, you'll want to keep a handle to the first instance when you create it:
var p1 = Processing.loadSketchFromSources('canvas_id', ['sketch.pde']);
When you're ready to "unload" and load a new sketch, I'm guessing (but don't know) that you'll need to clear the canvas yourself:
p1.exit();
var canvas = document.getElementById('canvas_id');
var context = canvas.getContext('2d');
context.clearRect(0, 0, canvas.width, canvas.height);
// Or context.fillRect(...) with white, or whatever clearing it means to you
Then, from the sound of things, you're free to attach another sketch:
var p2 = Processing.loadSketchFromSources('canvas_id', ['sketch2.pde']);
Again, I'm not actually familiar with that library, but this appears straightforward from the documentation.

As of processing.js 1.4.8, Andrew's accepted answer (and the other answers I've found in here) do not seem to work anymore.
This is what worked for me:
var pjs = Processing.getInstanceById('pjs');
if (typeof pjs !== "undefined") {
pjs.exit();
}
var canvas = document.getElementById('pjs')
new Processing(canvas, scriptText);
where pjs is the id of the canvas element where the scrips is being run.

How can I overlay SVG diagrams on Google Maps?

I would like to add an overlay image on a Google Map. The image is a SVG file I have generated (Python with SVGFig).
I am using the following code:
if (GBrowserIsCompatible()) {
var map = new GMap2(document.getElementById("map_canvas"));
map.setCenter(new GLatLng(48.8, 2.4), 12);
    // ground overlay
    var boundaries = new GLatLngBounds(new GLatLng(48.283188032632829, 1.9675270369830129), new GLatLng(49.187215000000002, 2.7771877478303999));
    var oldmap = new GGroundOverlay("test.svg", boundaries);
map.addControl(new GSmallMapControl());
map.addControl(new GMapTypeControl());
map.addOverlay(oldmap);
}
Surprisingly, it works with Safari 4, but it doesn't work with Firefox (with Safari 3, the background is not transparent).
Does anyone have an idea on how I could overlay an SVG?
PS1: I read some works like this or the source code of swa.ethz.ch/googlemaps, but it seems that they have to use JavaScript code to parse the SVG and add one by one all the elements (but I did not understand all the source...).
PS2: The SVG is composed of different filled paths and circles, with transparency.
If there is no solution to overlay my SVG, I can use 2 alternative solutions:
rasterize the SVG
convert the paths and circles in GPolygons
But I do not really like the 1st solution because of the poor quality of the bitmap and the time to generate it with antialiasing.
And for the 2nd solution, the arcs, ellipses and circles will have to be decomposed into small polylines. A lot of them will be necessary for a good result. But I have around 3000 arcs and circles to draw, so...

Here are some news (I hope it's better to put them here in an answer, instead of editing my questions or to create a new question. Please feel free to move it if needed, or to tell me, so as I can rectify):
My problem was the following:
var oldmap = new GGroundOverlay("test.svg", boundaries);
map.addOverlay(oldmap);
did not work on Safari 3, Firefox and Opera (IE is not enable to draw SVG).
In fact, this code produce the insertion (in a <div>) of the following element
<img src="test.svg" style=".....">
And Safari 4 is able to draw a SVG file as an image, but this is not the way to do for the other browser. So the idea is now to create a custom overlay for the SVG, as explained here.
That's the reason why I asked for this question (I am sorry, but HTML/javascript are not my strongest points).
And since there is a small bug with Webkit for rendering a SVG with transparent background with <object>element, I need to use <object> or <img> accordingly to the browser (I don't like this, but... for the moment, it's still the quick-and-dirty experiments)
So I started with this code (still work in progress):
// create the object
function myOverlay(SVGurl, bounds)
{
this.url_ = SVGurl;
this.bounds_ = bounds;
}
// prototype
myOverlay.prototype = new GOverlay();
// initialize
myOverlay.prototype.initialize = function(map)
{
// create the div
var div = document.createElement("div");
div.style.position = "absolute";
div.setAttribute('id',"SVGdiv");
div.setAttribute('width',"900px");
div.setAttribute('height',"900px");
// add it with the same z-index as the map
this.map_ = map;
this.div_ = div;
//create new svg root element and set attributes
var svgRoot;
if (BrowserDetect.browser=='Safari')
{
// Bug in webkit: with <objec> element, Safari put a white background... :-(
svgRoot = document.createElement("img");
svgRoot.setAttribute("id", "SVGelement");
svgRoot.setAttribute("type", "image/svg+xml");
svgRoot.setAttribute("style","width:900px;height:900px");
svgRoot.setAttribute("src", "test.svg");
}
else //if (BrowserDetect.browser=='Firefox')
{
svgRoot = document.createElement("object");
svgRoot.setAttribute("id", "SVGelement");
svgRoot.setAttribute("type", "image/svg+xml");
svgRoot.setAttribute("style","width:900px;height:900px;");
svgRoot.setAttribute("data", "test.svg");
}
div.appendChild(svgRoot);
map.getPane(G_MAP_MAP_PANE).appendChild(div);
//this.redraw(true);
}
...
The draw function is not yet written.
I still have a problem (I progress slowly, thanks to what I read/learn everywhere, and also thanks to people who answer my questions).
Now, the problem is the following : with the <object> tag, the map is not draggable. All over the <object> element, the mouse pointer is not "the hand icon" to drag the map, but just the normal pointer.
And I did not find how to correct this. Should I add a new mouse event (I just saw mouse event when a click or a double-click append, but not for dragging the map...) ?
Or is there another way to add this layer so as to preserve the drag-ability ?
Thank you for your comments and answers.
PS: I also try to add one by one the elements of my SVG, but... in fact... I don't know how to add them in the DOM tree. In this example, the SVG is read and parsed with GXml.parse(), and all the elements with a given tag name are obtained (xml.documentElement.getElementsByTagName) and added to the SVG node (svgNode.appendChild(node)). But in my case, I need to add directly the SVG/XML tree (add all its elements), and there are different tags (<defs>, <g>, <circle>, <path>, etc.). It is may be simpler, but I don't know how to do.. :(

I spend the last evening on this problem, and I finally found the solution to my problem.
It was not so difficult.
The idea is, as Chris B. said, to load the SVG file with GDownloadUrl, parse it with GXml.parse() and add in the DOM tree every SVG elements I need
To simplify, I have supposed that all the SVG elements was put in a big group called "mainGroup". I have also supposed that some elements can be in the file.
So here is the library, based on the Google Maps Custom Overlays:
// create the object
function overlaySVG( svgUrl, bounds)
{
this.svgUrl_ = svgUrl;
this.bounds_ = bounds;
}
// prototype
overlaySVG.prototype = new GOverlay();
// initialize
overlaySVG.prototype.initialize = function( map)
{
//create new div node
var svgDiv = document.createElement("div");
svgDiv.setAttribute( "id", "svgDivison");
//svgDiv.setAttribute( "style", "position:absolute");
svgDiv.style.position = "absolute";
svgDiv.style.top = 0;
svgDiv.style.left = 0;
svgDiv.style.height = 0;
svgDiv.style.width = 0;
map.getPane(G_MAP_MAP_PANE).appendChild(svgDiv);
// create new svg element and set attributes
var svgRoot = document.createElementNS( "http://www.w3.org/2000/svg", "svg");
svgRoot.setAttribute( "id", "svgRoot");
svgRoot.setAttribute( "width", "100%");
svgRoot.setAttribute( "height","100%");
svgDiv.appendChild( svgRoot);
// load the SVG file
GDownloadUrl( this.svgUrl_, function( data, responseCode)
{
var xml = GXml.parse(data);
// specify the svg attributes
svgRoot.setAttribute("viewBox", xml.documentElement.getAttribute("viewBox"));
// append the defs
var def = xml.documentElement.getElementsByTagName("defs");
//for( var int=0; i<def.length; i++)
svgRoot.appendChild(def[0].cloneNode(true));
//append the main group
var nodes = xml.documentElement.getElementsByTagName("g");
for (var i = 0; i < nodes.length; i++)
if (nodes[i].id=="mainGroup")
svgRoot.appendChild(nodes[i].cloneNode(true));
});
// keep interesting datas
this.svgDiv_ = svgDiv;
this.map_ = map;
// set position and zoom
this.redraw(true);
}
// remove from the map pane
overlaySVG.prototype.remove = function()
{
this.div_.parentNode.removeChild( this.div_);
}
// Copy our data to a new overlaySVG...
overlaySVG.prototype.copy = function()
{
return new overlaySVG( this.url_, this.bounds_, this.center_);
}
// Redraw based on the current projection and zoom level...
overlaySVG.prototype.redraw = function( force)
{
// We only need to redraw if the coordinate system has changed
if (!force) return;
// get the position in pixels of the bound
posNE = map.fromLatLngToDivPixel(this.bounds_.getNorthEast());
posSW = map.fromLatLngToDivPixel(this.bounds_.getSouthWest());
// compute the absolute position (in pixels) of the div ...
this.svgDiv_.style.left = Math.min(posNE.x,posSW.x) + "px";
this.svgDiv_.style.top = Math.min(posSW.y,posNE.y) + "px";
// ... and its size
this.svgDiv_.style.width = Math.abs(posSW.x - posNE.x) + "px";
this.svgDiv_.style.height = Math.abs(posSW.y - posNE.y) + "px";
}
And, you can use it with the following code:
if (GBrowserIsCompatible())
{
//load map
map = new GMap2(document.getElementById("map"), G_NORMAL_MAP);
// create overlay
var boundaries = new GLatLngBounds( new GLatLng(48.2831, 1.9675), new GLatLng(49.1872, 2.7774));
map.addOverlay( new overlaySVG( "test.svg", boundaries ));
//add control and set map center
map.addControl(new GLargeMapControl());
map.setCenter(new GLatLng(48.8, 2.4), 12);
}
So, you can use it exactly as you use the GGroundOverlay function, except that your SVG file should be created with the Mercator projection (but if you apply it on small area, like one city or smaller, you will not see the difference).
This should work with Safari, Firefox and Opera. You can try my small example here
Tell me what do you think about it.

This question was briefly discussed on the Google Maps API Group. Here's what they said:
I've not tried it, but SVG is a subset
of XML, so you can read them with
GDownloadUrl() and analyse them with
GXml.parse(). On some wonky webservers
you may have to change the file
extension to XML.
You then have to crawl through the XML
DOM, writing the SVG that you find
with document.createElementNS() and
.setAttribute() calls...
There are also a some Google Maps SVG examples here and here.
Good luck!