Author Topic: Rounded/smooth start-end arrows  (Read 1095 times)

Offline ashokv

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Rounded/smooth start-end arrows
« on: February 11, 2016, 09:30 AM »

I need to have a rounded/smooth start-end arrow from one process to another (example.png) instead of a horizontal start-end arrows (sankey.png). How to do this. Pls help.


Offline pbeilschmidt

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Re: Rounded/smooth start-end arrows
« Reply #1 on: February 11, 2016, 05:13 PM »
Hello Ashok,

in the top image (example.png) the Sankey arrows start to curve right at the node. In the lower image (sankey.png) they have an initial horizontal segment, before they start to bend.

In our implementation we have opted for the latter for a number of reasons: If you have more than one arrow connected to the node, forcing the departing (or arriving) arrows to run in parallel (stacked) at least at the initial (final) segment, before branching out in different directions. This avoids overlapping of arrows. Also, when connecting to the nodes from different sides (from North, South, East, West) - as is possible in the Sankey diagrams in e!Sankey - the initial vertical/horizontal segment ensures that there is no overlapping.

We have made investigations into the other arrow display, which is more of a Bézier curve style. The curves are softer and rounder and this might in some cases be the preferred way of display. We have also done the first test implementations for this arrow type, however, this has not yet been added to our software. Since e!Sankey is not limited to simple left-to-right distribution diagrams, we have to consider the behaviour for all possible arrow routings and degrees of freedom for connectivity settings at the nodes.

We might eventually include this arrow style in one of our next releases ... stay tuned. 
Peter Müller-Beilschmidt
e!Sankey Forum Moderator
ifu Hamburg GmbH