Physics in Computer Games

Physics is one of the key elements of any computer game or animation. This is especially true, when it comes to 3D environments. Physics applies to every aspect of the real world, from how objects act on each other through obvious collisions down to the more in depth conservation of energies and momentums. These same concepts apply to Computer Generated Environments (CGE).

3D CGEs always require a few key laws to be followed in order for them to look at least somewhat realistic. Without at least implementing these simple physics concepts, the interaction of polygons will look unrealistic. Polygons can easily be treated as simple masses, and thus, applying physic law to them is simple.

One of the most important laws that must be followed is the Law of gravity. Without gravity, objects will either simply float about aimlessly. Making objects stick to the ground isn't a solution, or falling objects would hit the ground instantaneously, and it would look pretty terrible. The Laws of gravity must be followed.

Second, the three laws of Newton must be followed. They describe the way that forces act on objects. The 3 laws simplified are as follows:

1. Velocity remains constant unless a force acts on the object.

2. Sum of the forces equals the product of the mass and its acceleration.

3. For every action, there is an equal reaction, just opposite in direction.

Third, are the conservations. This includes Conservation of Momentum, Conservation of Energy, and Conservation of Torque. This page wont get into the latter, since it isn't really necessary for CGEs.

To get more information about any of these Physics concepts and laws and how they apply to 3D CGEs, use the menu to browse the rest of the site. Have Fun! Don't hurt yourself, and keep an eye out for an easter egg.

Gravity is one of those things that simply has to exist.

A CGE that lacks gravity will more than likely have some other form of keeping objects together and on a plane, such as simply making all the objects stick to the ground. This isn't the best way to go about doing this. Gravity would create a much more realistic emulation of reality.

Sure, objects simply tied to the ground can work, but if these objects were to fall, then the fall would have to be pre-rendered, or sequenced. A simple change in the height from which an object falls, and this wouldn't look realistic. The object would look as if fell too quickly, or the environment would be limited to set height increases.