Hacker Cinema
The Trespasser
1929 · Film · 90 min
Directed by Edmund Goulding
A stenographer who works for a lawyer falls in love with and marries a wealthy young man. His family has the marraige annulled, after which she gives birth to a child. Her former boss helps her out to ensure the child's welfare, which starts gossip that she is a "kept woman."
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Not movie related, but this let’s play of the JP game Trespasser also goes into a lot of detail and is generally super interesting
https://www.youtube.com/playlist?list=PL0058A651EB882B48
The principle of least constraint is the basis for rigid body mechanics based contact forces. This has been known since the days of Gauss and Hamilton, and is fundamentally how restitution and collision forces are derived in Lagrangian mechanics. There's a long literature on this going back more than a hundred years.
It's true that some commercial solvers like Ansys use spring/penalty methods, but this is due to the spring forces being easier to couple to other solvers. It's harder in the Ansys force/velocity formulation to combine things like elasticity and fluids to their rigid body solver. To deal with the instability of systems of many stiff springs they have to take many small timesteps to avoid convergence issues.
More recently techniques like XPBD have been gaining popularity, particularly in film, which use purely positional constraints and variational methods to combine many different types of physics simulations. There's a really great and approachable series of videos by Matthias Muller on youtube which goes through how to implement all this in JS https://matthias-research.github.io/pages/
Finally it's funny you should mention games, since many older games used spring methods for physics. It was only when constraint based solvers became popular after Havok/Half-Life 2 did we start to see games with real rigid body dynamics and stable stacking of boxes. Older physics games like Trespasser ( https://en.wikipedia.org/wiki/Trespasser_(video_game) ) had many bugs due to the use of hacky spring physics. For a good explanation of how games do it today look at Erin Catto's work on Box2D https://box2d.org/publications/