Help with Vega Gantt Chart

Hi everyone,

I am currently working on a customized Gantt Chart visualization for Power BI, which you can find on my GitHub repository: Compact Power BI Gantt Chart.

This visualization uses Vega and represents all subactivities of a task on the same row to maintain a compact layout.

At the moment, the hover feature displays details at the "media" level, but I would like to extend this functionality to also show details for "waves" at the product level. Specifically, I am aiming to display aggregated details such as total spend and activity range for a product wave when hovering.

If anyone has experience with Vega or has worked on similar projects, I would greatly appreciate your insights or suggestions on how to implement this feature. Relevant documentation or examples would also be very helpful!

giammariam, since I know you have expertise in this area, your input would be especially valuable.

Thank you all in advance for your support and ideas!

Best regards