The physics of a string in 'The Last of Us Part 2' are the most impressive to professional programmers, and they have good reasons
Neither Ellie's dramatic story and her descent into darkness, nor her extraordinary violence nor the overwhelming creativity of her level design. What is drawing more comments among programmers who are testing 'The Last of Us Part 2' is a simple rope. Or rather, their realistic behavior, their physics and their interaction with the environment and the characters. A hyper-realistic rope that has much more work behind it than it appears.
It is undoubtedly further proof of the sickly detail that Naughty Dog has injected into every aspect of the game. We spoke in our critique of the invisible linearity of the levels, or of the executions, always different. The string, which appears at specific moments as an integral part of the puzzle resolution, is an almost exhibitionist sample of the skill of the game programmers, and to understand it you have to analyze everything that this object is capable of doing.
# ラ ス ア ス 2 ロ ー プ 関 連 の 挙 動 や ば い な ロ ー プ の ど こ で も 持 て て, 持 っ た 場所 に 応 じ て い い 感 じ に た ぐ り よ せ て 巻 い て く れ る 地形 に か ら ま せ て も し っ か り 絡 む .https:.. //T.co/OrGVJ6rXNf pic.twitter.com/U7FvAWdYqh- ニ カ イ ド ウ レ ン ジ (@R_Nikaido) June 20, 2020
The one who blew up the hare was the Japanese tweet R_Nikaido, who works at indie studio 29Games. In a video she posted on Twitter, you could see how Ellie plays with the rope, which she throws through the window of a rickety caravan and then winds up on the side of an exit door. The response from Xavier Coelho-Kostolny, character designer for the Magnopus studio, was "I guarantee this made 15 people cry during development." Notewell Lyons, developer of the PSR Digital collective, replied: "I am crying. My main task is that of a level designer, and I don't have any of the necessary knowledge to even imagine how to do that."
The identity of the person responsible for this spectacular work soon came to light. Kurt Margenau, co-director of the game, claimed it was "the work of incredible physics programmer Jaros Sinecky, building on what he already did in 'Uncharted 4.'" A second Naughty Dog member, Maksym Zhuralov, clarified that "we don't cry, but we do sweat quite a bit. Our physics programmer Jaroslav did the hardest job. He's devilishly good."
Over the past few days, other programmers have added praise to the work of Naughty Dog: James Benson ('Half-Life: Alyx'), Douglas Copeland (Funcom) or David Clyde ('Overwatch'), among others. , they have reacted between surprise and admiration. But ... is it so much? Why has a simple rope to solve a pair of not especially memorable puzzles caught so much attention among professionals?
The secrets of the rope
This video from the youtuber Life28SK summarizes quite well the findings of the physics of the rope, which is actually a cable that is intended to start a generator. There is a procedural animation for the (oddly satisfying) gesture of winding the rope, and another for the gesture of reaching the end of it. We have an amazing and very natural gesture of Ellie's body, letting go by inertia when she runs, she gets jerked when the rope runs out.
As for the behavior of the object itself, the rope realistically travels the surface of the objects it encounters in its path, and cannot be crossed by Ellie if it gets in its way. The sliding and knocking sound effects of the plastic plug as it crawls across the floor, of course, go hand in hand. A whole catalog of "unnecessary" details that redound to the realism of the game.
Speaking to Polygon, programmer Coelho-Kostolny explained that this flexible material makes it especially difficult to design interactions with the object. "Unlike a box or a barrel, a piece of cloth, string, or other flexible materials have to be enabled to change shape when they collide with other objects ... and with themselves." The programmer, however, acknowledges that " Most of the cable and string simulations in the games aren't much more complex today than they were 16 years ago in 'Half-Life 2'. "
"What the string from 'The Last of Us Part 2' shows," he says, "is a series of complex behaviors, such as coiling around objects in a complex collision, as well as maintaining the correct length and applying opposing forces to the character." . And unsurprisingly, this is not done alone: "the people who encoded and implemented the string need to have a deep understanding of the game's physics systems, as well as the systems involved in their application to designs" Coelho-Kostolny It talks about a joint work of the quality control team, the programmers and the graphic designers.
Total working time to achieve this: no less than three months. Three months to implement an object that for the inattentive player may go unnoticed, but which is confirmed as further proof that in cases like these, the devil is in the details.