The relevant paper is Lars Blackmore's Lossless Convexification ( http://www.larsblackmore.com/losslessconvexification.htm ), which (to my understanding) he basically went to SpaceX to put into practice/scale, and which drives the rocket's realtime control adjustment for landing.
It should be said that the methods were developed before he joined SpaceX and were used at NASA / JPL for at least on Mars mission.
GPU acceleration of dynamically scaling cell-based fluid dynamics simulation. Video lecture / demo from 2015; 45 minutes.
I don't know if it was state-of-the-art but it looked impressive to me as a layperson.