I have created a Gantt view on a list, showing the Gantt chart and several columns. One of my list columns is a R/Y/G status column. I would like the cell that displays the R/Y/G status to show the color as well as the letter. This doesn't seem like an uncommon scenario, but I have not found anything to help me figure out how to do this on the Gantt view. I am OK using JQuery or any other viable technique to achieve the end result.
This describes how to attach a js file to gantt view and how to display messages based on various conditions. RenderField function returns HTML which is then displayed in gantt view. This is very similar to what you need.