#5 Request support for splines="true"

[Learned By Error]

Thank you very much for your most excellent tool. I have been using GraphViz for a long time usually via perl. I now have a need where I need some other people to develop the models and do the work. These resources are not coders but are very good in Excel. I found you tool and pretty quickly converted a data set over to it including creating the needed styles. With only one exception, it worked perfectly!

The exception is the value 'true' is not access in the list of splines. This option works by far the best for the graphs that we are creating. I am currently working around it by saving the GV file, editing it and running dot manually.

I took a look to try to add this to the list but failed. I found your settings spreadsheet and added it to the data validation list for O77. This allowed me to specify tree for default but broke when trying to generate the graph. I was unable to find where the list is defined for the Ribbon control.

I would appreciate it if you would be so kind as to add this option.

Thank you,

lbe

[Jeffrey Long]

Thank you for the compliment. I don't receive much feedback on this tool, and often wonder if anyone uses it. Your note is very encouraging.

I have added the option you requested, and a little more. The distribution is available for download. The version number is 4.7.14 in the "about..." worksheet.

I added the values '', 'true', 'false', and 'compound' to the Splines dropdown list. If you choose the '' entry then the spline attribute is omitted from the DOT file and the rendering of the edges uses the default method of the layout program. I noticed on the "attributes" worksheet that the description for the splines attribute was missing , so I updated that also.

I am really curious why splines="true" works differently that splines="spline" for you when the documentation at https://www.graphviz.org/doc/info/attrs.html#d:splines says that "spline" is a synonym for "true". If you can share an example graph I would be interested in seeing the differences.

I'm sorry you were having to run Graphviz manually. That takes away much of the usefulness of this tool. There is a documented feature you could have used to set splines="true" and still render the graph in Excel. This feature will work for overriding most ribbon attributes, and let you specify Graphviz attributes such as ranksep, and nodesep which the spreadsheet does not automate.

The task is to add what I call a "native" command by typing the "greater than" character in the "Item" column, and the Graphviz statement in the "Label" column. The text in the Label column will be written into the DOT file without interpretation.

If you entered:

Item	Label	Is Related to Item
>	splines="true";

then this attribute value would be written into the DOT file after the ribbon options were written. Graphviz will use the most current value, i.e. the last one it encounters.

I use this feature when I want to lock my graph options. For example if I always want the graph rendered with 'fdp' I will put in a line:

Item	Label	Is Related to Item
>	layout="fdp";

or if I want 'dot' to always render left-to-right I will put in a line

Item	Label	Is Related to Item
>	rankdir="LR";

or to control dot's spacing of the nodes:

Item	Label	Is Related to Item
>	ranksep="0.375"; nodesep="0.50";

(you can specify multiple attributes per line)

As for modifying the Excel Ribbon, it can get complicated. The ribbon is a mixture of static lists and dynamic lists based on the situation.

For example, if you change the color scheme, the color lists must change dynamically to the list of colors which the color scheme supports. In this case the values are retrieved from a named range specified on the 'HELP - colors' worksheet.

For lists like the splines dropdown which have a fixed set of values, a static list is used. Those values are contained in an XML file embedded in the workbook.

There are a number of tutorials and videos on the web which explain the general concepts behind the ribbon controls which are in the spreadsheet. Here is a link to a good one. https://www.contextures.com/excelribbonaddcustomtab.html

I hope this addresses your needs.

Best regards,
Jeff