Generate a Gantt chart for any given sub-hierarchy of headings

[novoid]

My feature request is that - similar to many standard export Org features - elgantt can generate a chart for (1) all "elgantt-agenda-files" as you already support as well as (2) a whole Org file as #1 refers to as well as (3) a specific sub-hierarchy of headings.

Background

The reason why I do think that this is an feature worth implementing is that many people tend to follow the same strategy as I do to have only a few but rather large Org mode files. This way, I only curate one single Org mode file for everything that deals with my day job. This rather large file holds at least dozens of projects. Obviously, I would like to generate separate charts for each of them. As far as I understood your tool, this is not possible yet.

[legalnonsense]

Should not be difficult. Elgantt draws everything based on the results of an org-ql query, so it should not be hard to allow users to write a custom org-ql query and act only on those results, which would allow limiting it to certain trees, etc.

[legalnonsense]

Try to switch to the custom-org-ql branch, and set the variable elgantt-custom-org-ql-query as described in the docstring. Org-ql is pretty robust and should allow you to customize what headings and files are shown. See https://github.com/alphapapa/org-ql#function-org-ql-select