Dagre layout with long labels in cytoscape.js - cytoscape.js

I'd like my dagre layout to take the label length into consideration for the layout calculation. Right now I have overlapping labels but dagre can definitely take the label length into consideration (for example in http://cpettitt.github.io/project/dagre-d3/latest/demo/sentence-tokenization.html).
How can I make my dagre layout take label length into account with cytoscape.js?

I got an answer for the github issue I created.
This required changes to several layouts themselves to take into account BB in lieu of simply w/h. The lib only included w/h until more recent versions, so the layouts used those values.
You can build off unstable to see the changes.

Related

Why Cytoscape.js graph is not spanning the entire width of a bootstrap card?

I am using cola layout to render a Cytoscape graph inside a bootstrap card element. However, the graph mostly tries to span vertically and in spite of having plenty of spaces in the horizontal direction, it does not span there. See the following screenshot.
To reproduce the issue please use the following Electron fiddle gist:
https://gist.github.com/wasimaftab/33ab4ef9134b8c2b4c7afed4392b6520
I'm using cytoscape#3.16.1 and cytoscape-cola#2.4.0
Even after removing the nodes added with fixed x and y coordinates graph still looks the same (see screenshot below).

Cytoscape with Haystack or Bezier Layout: How to Shorten Edge Length

I am new to Cytoscape, and I have a working graph, but my nodes are very far apart. While I realize Cytoscape generates everything dynamically, it seems like it should be possible to say "use half as much space between nodes".
This demo:
http://js.cytoscape.org/demos/2ebdc40f1c2540de6cf0
seems to show that you can dynamically change the lengths of edges. However, when I look at the source code (https://gist.github.com/maxkfranz/2ebdc40f1c2540de6cf0), I can't figure out how it works.
It seems like the demo is passing a edgeLength option to makeLayout, but the Cytoscape documentation doesn't even mention edgeLength as a valid option.
Can anyone more experienced with Cytoscape point me to how I can shorten the edges between my nodes?
Each layout is different, and the combination of values you use depends on what effect you're trying to create.
Force-directed layouts usually have a weight that affects edge length by spring forces.
In general, the bounding box can affect the length.
Some layouts have spacing adjustment multipliers.
Some layouts have other, miscellaneous options that affect edge length.
You have to look at the options for the layout you're interested in and experiment with them to get the effect you're looking for. That holds true for every layout for every graph theory lib, Cytoscape included.

cytoscape.js node unwanted overlap and unexpected styling

I've got a working cytoscape.js instance that looks like this:
I have been trying unsuccessfully to configure the graph so that the node labels don't overlap. The graph uses arbor for layout. Playing with the repulsion levels doesn't have much effect on the problem. Gravity (or lack thereof) doesn't either. Is this a layout issue or a cytoscape.js config issue and how do I fix it?
Secondarily, node shape is supposed to be a 40x40 ellipse, which it generally is. But when a node is grabbed, it displays as a rounded rectangle. Why?
I've created a gist with my javascript and some data. It's dependent on jQuery (~2.1), cytoscape.js (>=2.3.9) and arbor.js as provided in the cytoscape.js lib directory. And it needs <div id="cy"></div> for a target.
(1) Overlap is a function of layout. If changing layout parameters is unsuccessful for your usecase, a different layout is probably the solution.
(2) That's the overlay -- not the node's body.

position edge labels using cytoscape.js

Due to the nodes and edges between nodes, the breadthfirst algorithm is positioning nodes in such a way that labels on the nodes are overlapping one another. Is it possible to have the algorithm either position the nodes or the edge labels so they don't overlap, or attempt to minimize overlap?
You may be interested in label autorotation for edges, planned for 2.4 and implemented in unstable. As for the logic you'd like in the layout itself, it may be a too tight coupling of implied rendering behaviour to the layout. Whereas things like node.outerHeight() can be taken into consideration directly and explicitly in layouts, this would rely on the layout assuming certain rendering behaviour.
I think there's a factor option for spacing the nodes farther apart in the breadthfirst layout, and if you want to discuss other new ideas like it I would be happy to discuss it in a ticket in the tracker.
Thanks

How can I get the height of a QListWidgetItem in a QListWidget in PyQt?

Actually, how can I extract size of gui elements in general in PyQt?
So far I have only found sizeHint mentioning anything regarding sizes in PyQt.
Could anyone please explain how sizes works in PyQt?
In general, it's not possible to guarantee the exact sizes of widgets, because there are so many different factors that come in to play. Widgets will rendered differently depending on the window manager in use, the current GUI style, the fonts, etc - and each platform has it's own peculiarities.
To get a better understanding of all this, I would suggest you take a look at Qt's own overviews of window geometry, widgets and layouts and layout management.
To answer the specific question on the height of QListWidgetItems: they will have whatever height is calculated by the QListWidget when it lays out its items. This may take into account the items' sizeHint, which can be set programmatically with QListWidgetItem.setSizeHint.