What are Physics Engines?
As defined by IBM in an article on open source physics
engines, "A physics engine is a simulator used to
create a virtual environment that incorporates laws from the
physical world." This is what makes a video game feel
realistic and comfortable to play, and gives the player a
sense of immersion by making the game feel like real life. On
the most basic level, physics engines implement methods for
games to create objects that move based on a set of equations
that describe motion, or kinematics equations.
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These equations describe how point masses move and rotate under constant acceleration. However, as we observe the world around us daily, we realize that objects do not always act as point masses. Most objects can bend and stretch and have varying densities. So, as game engines are becoming more and more advanced, striving to become as realistic as possible, a lot of development has been made in what is referred to as soft body physics. Below is a video of a soft body car in cry engine 3.