I am using InfoVis to generate a space tree visualization in one of my projects. Since this is an interactive web site, the Space Tree needs to be regenerated each and every time the user has changed preferences.
This requires the Space Tree to be completely cleared and re-draw a new tree on the same space. In addition, the charting area can be re sized as the page size varies. This requires re-draw of the Space Tree.
I came across several issues while trying to clear the previously drawn Space Tree before drawing the new one. I am using the following code segment to clear the previous drawing, but it's failing miserably.
st.clearNodesInPath();
st.labels.clearLabels(true);
st.canvas.clear();
If anyone can guide me how to resolve this that would be great as this is blocking my progress. Thanks in advance.
This was resolved in the following manner.
The InfoVis chart draws it's elements as HTML div elements inside the parent element. The problem was due to remainings of those generated div elements even after clearing up the data structures. Those were clearly shown in the previously attached images.
This was resolved in the following manner.
var list = document.getElementById("idOfParentElement");
list.removeChild(list.childNodes[0]);
The code fragment extracts the parent InfoVis element and clears up all of it's generated child elements. This will eventually clears the canvas object where the visualization will be drawn.
This resolved my issue. Hope this helps for anyone who is having the same issue.
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I am trying to make a visualization using d3 which is basically a scatter plot with links between the points. (I have attached a .gif of the existing java based visualization)
The points can be added by double clicking other points. On hovering over a point, I wish to have links drawn between the point and all its partners on screen.
I have the part where on double clicking a node, its partners are added. What I need help with is drawing the links (primarily I am not able to understand how can I get the x1,y1,x2,y2 values required to draw the links).
This is what my DOM looks like:
I have seen a lot of examples online but somehow not able to figure the solution - if anyone could link me to a similar visualization or share a fiddle/ give some pointers on how this can be achieved I would be really grateful.
First the simple stuff: here are 2 mechanisms for drawing the lines.
Next, in terms of the data representation of the lines, check out how links are typically drawn when working with the force directed layout.
Important: Do not get distracted by the existence of the force layout in this example and by the fact that the force layout works with these links (which are passed into it by calling force.links(links)). That aspect of the example probably doesn't have an equivalent in what you're trying to achieve.
However, do notice how the links array is constructed —— with each element of the array being an object with pointers to source and target datums. In your case, you'll want to work with a similar links array, where source is the node under the mouse and target is a node that's connected to it. So you'll end up with an array of links who all have the same source datum but unique target datums.
You can then bind the links array (via the usual .data() method) to a d3 selection of line or path elements. Once you bind, you can use the usual enter, update, exit pattern to append, update and remove (on mouse out) the drawn lines.
Given a source and target datums, you can calculate the x and y of the endpoints in the same way you currently calculate the translation of each <g> element, presumably using a d3 scale.
I am converting an existing code base from using Flash to using CreateJS but I am in need of a way to stop the Stage update and inspect the EaselJS GUI elements
for debugging.
My list of requirements for the debugger is
It must be possible to stop the propagation of CreateJS ticks to the non-debug parts of the GUI so that these parts do not change during inspection.
In inspection mode, it must be possible to see the hierarchy tree of the non-debug parts of the GUI.
In inspection mode, when an element in the hierarchy tree is selected, then the corresponding visible canvas graphics must change appearance to clearly distinguish it from the other graphics on the canvas, and so that its boundaries are clearly visible.
In inspection mode, when a point is selected on the canvas, then the corresponding element must be visible and highlighted in the hierarchy tree.
In inspection mode, when a point is selected on the canvas, then the following properties must be displayed for the corresponding element: coordinates & size.
To achieve the above, I need to implement at least these parts.
Stage traversal and data extraction.
Tree presentation of the data extracted.
Highlight of specific stage objects.
Control of the Stage ticking.
Are there libraries that can help me create such an inspector tool?
The EaselJS-Inspector is an example of how to solve everything above, except that I use a fixed size for all DisplayObjects.
The problem is that Shapes do not have a size unless one manually sets it.
I am doing visualization with the JavaScript InfoVis Toolkit, in particular the hypertree. I am loading data dynamically and sometimes the labels around the nodes overlap and clutter. I would like to avoid this clutter by altering the label positions.
Here is an example of cluttering (the top and bottom nodes):
I imagine that I would loop through each x,y coordinate, give it some bounding box and do basic collision detection, and update positions accordingly.
For this library, I see the demo shows a onPlaceLabel() function, but (if I understand correctly) at that moment I wouldn't know the position of every other node's label. So, I am looking at onComplete(), where I see I can access each node as follows:
onComplete: function(){
ht.graph.eachNode(function(n) {
console.log(n);
}
}
But the node information does not include its label positions, only their positions relative to the center node. Is there a way to access the labels in this way and be able to update their positions?
I'm using the tree layout and code similar to http://mbostock.github.io/d3/talk/20111018/tree.html
I modified it for a top down orientation.
As each node is opened/expanded, the other open nodes compress to fit everything within the SVG element. Is it possible to prevent that? I would think modifying the x component of each node would be the approach but have not been able to accomplish that. The nodes move over, but are still compressed together.
Also wondering how to change the linking lines from a bezier to right angles/straight lines. Perhaps a separate question is needed.
The compression is automatic in the tree layout (and part of its point). There's no way to turn that off. However, you can simply make your SVG large enough to contain the entire expanded tree without compression. Note that this means that unless your screen is large enough scroll bars will be displayed even when everything that is visible fits onto the screen.
The links connecting the nodes are generated using the diagonal line generator in the example. In principle, you can replace this with any other line generator (e.g. d3.svg.line), but in practice some changes will be necessary because the diagonal line generator accesses source and target nodes in a special way. For a normal line generator, you would need to convert this structure to a two-element array and for each element specify how to access x/y coordinates. Then you can use any of the interpolations to get the curve you want.
What I ultimately want to be able to do is to have a circle follow a path that is updated by a server real time. Think of it as a target following a line. I already know how to make a circle follow a path thanks to this fiddle. But my problems come from how to update the line and course of the circle dynamically as ultimately I want a target to follow data being generated by a server and I am not sure how to do it.
For ease of testing I have created a jsFiddle allowing you to click on the screen to place a point, with the aim of this simulating the server data. The circle shouldl then move towards each point in turn as you click it.
So how do I update an existing path and make the animation continue seamlessly without affecting previous parts of the path?