AutoGantt
This program was developed and written by Des Traynor. It is released under the GPL. This means you can do what you like with it, run it, copy it, redistribute it even modify it and release your version too! You can even sell it. The only restriction is that if you distribute it , it too must also be under the GPL. See the GPL page for more info.
This program allows you to draw Task Graphs, specify the time units allocated with each task , and show the dependencies between task (e.g. open file must come before write to file) A valid task graph is one where there is only one starting point, only one finishing point (child node), and all nodes are connected. Screenshots below show a valid task graph, and how it gets converted into an equivalent Gantt Chart. Included in the zip file are my report detailing the functionality, all the code (obviously) , and a readme file. I hope you find it useful. Downoad the code here
Figure 1. This shows a valid Task Graph drawn using the tool , with processing times set and dependencies shown.
Figure 2. This shows a valid Gantt Chart created from the previous Task Graph , with 4 processors selected and speed up and efficiency shown.