Game Development Reference
In-Depth Information
The key issues with “personal” military lasers are how to generate the required power and
how to keep them cool enough so they don't cook the person carrying it. As long as you can
come up with a reasonably plausible technology explanation to accomplish those two objectives,
your futuristic laser systems should pass the “realism” test. Then again, you may say “to heck
with realism” and arm your soldiers with 10 megawatt CO
2
laser rifles. In any case, if you do
decide to create your own laser systems, you can still use Equations (14.5) and (14.6) to estimate
the damage caused by them.
Laser Visual Effects
The last topic this chapter will cover is how to show laser beams in your game simulations. This
may come as a shock to you, but Hollywood takes some liberties when depicting laser beams.
A laser beam is never visible in the vacuum of space, so the stirring battle scenes in movies like
Star Wars
would not look that way in real life. The laser beam would be apparent only if it
caused the surface of a spaceship, starfighter, or whatever to glow from the buildup of heat.
A laser beam is generally not visible when it travels through air either and usually can only
be seen if it passes through dust, smoke, mist, or fog. Very high-intensity laser beams can be
visible in clear air due to effects known as
Rayleigh scattering
or
Raman scattering
. Most high-
energy military lasers emit infrared radiation rather than visible light, so you wouldn't be able
to see those types of laser beams under normal circumstances. Another thing to keep in mind
is that laser beams travel at the speed of light. You will never see the beam traveling from point
A to point B. Instead, to a human observer the beam will traverse the distance from laser to
target instantaneously.
Now, of course, it is a lot more fun and interesting in games if the laser beams are visible,
so this may be an instance when you want to ignore the proper physics to achieve a desired
visual effect. If the setting for your game is the surface of a dusty planet and/or if the combatants are
using extremely powerful lasers, you can probably show the laser beams with a clear conscience.
Even if your game is set in the emptiness of outer space, your users would probably forgive you
if you showed the laser beams.
Summary
In this chapter, we looked briefly at the world of lasers. Starting with a little historical background,
we discussed the structure of atoms and how particles of light called photons are generated.
We saw that under the right circumstances a laser beam can be generated where all the photons
have the same wavelength and are traveling in the same direction. We discussed the different
types of lasers including military lasers that can destroy missiles and airplanes.
Some of the other things this chapter covered include the following:
•
How a photon can strike an atom and stimulate the emission of an identical photon
traveling in the same direction.
•
How lasers can be created from many different substances—gases, liquids, and solids.
