Ω Nvidia introduced a fancy new technology called Flex back in 2013-2014. It is a position based constrained particle simulation library that takes advantage of GPU calculations, and it blew our minds back then (at least mine) - all those pretty water simulations running real-time... I personally thought this tech will make it's way into production software pretty fast and save us all from heavy slow water and softbody simulations. And it did not happen. And i completely forgot about flex until just recently. I stumbled upon this pedrocabrera 's videos and remembered about the existence of flex. Looks like with years it got some improvement but overall remained the same GPU particle based simulation library for mostly real-time applications. By coincidence i just started learning HDK, so that was a nice testing opportunity, since Pedro decided for some reason to make a Softimage (R.I.P.) integration. So here are a couple of my thoughts on this library and why it will not