I was looking around for gravity gradients then got sidetracked by looking at pork-chop plots because they're extremely cool. I'm still struggling to fully understand them, but I did find an interesting one that seems to be talking about the delta-v requirements for a mission to mars in 2354 leaving from Earth in 2353.
Original Link: http://www.projectrho.com/public_html/rocket/images/mission/Mars2353PorkChop.png
It's from projectrho, but I was wondering if anyone could describe more in detail about how, given two dates, you would decide the values for each of the points in the plot? Is it simply calculating the best possible scenario for delta-v budget in terms of a transfer between the two bodies for the provided dates? What types of delta-v does this plot account for: aerobraking, impulsive maneuvers, gravity assists? If you have more specific information about the porkchop plot itself (as in what the specific mission was) I would also like to see that, I found this on google and it led me to this page.