Light Placement
Of course the most obvious of the things you'll be doing with those different light types is the placement of the lights.
Regardless of the types of lights you have to work with, your job is to use what's available to create the lighting, so an understanding of lighting will help form the decisions of why you may be lighting a given area in a specific way.
Many times you'll have already approved concept art to work from, so in a sense, will be working to match the overall feel of the lighting that was created in the concept. Note that I say "overall"...meaning how closely you need to follow the concept will again be based on the methods of the company you're working for.
Some companies will insist that you follow the concept art down to every detail, while for others, the concept is more of a "guide", and you'll have plenty of creative freedom in addition to the concept you're working with.
And of course, there will also be plenty of times where there's no concept art as well, and may only be a description, like "warm sunset" or "night with torches".
There isn't room in this article for a full-blown introduction to the basics of lighting (I may do that later), but this is where you'll be defining the time of day, mood, and highlighting path elements, etc.
Cheating Like Crazy
In your average outdoor scene, we of course light the scene primarily with the sun, and then have sky fill that will fill in the shadows. That happens regardless of whether you have static or time of day/dynamic lighting in your engine. So you might think that there's nothing more to be done, with the sun and sky in place.
But the truth of the matter is that there's a whole bunch of cheating that's going on to make things more visually interesting. If it's done right, you'll never notice when you're playing the game.
A few examples of cheating with lights:
1) An area that would look really cool if only the sun was at a slightly different angle. This can be remedied by the addition of one or more spotlights, that match the intensity and color of the sunlight. If they’re placed properly, players won't notice that it's not just sunlight.
2) Nice looking God rays (Crepuscular rays) that might be seen in a cave or through holes in a deserted building, that don't actually match the direction of the sun, but are placed in a way that looks the most interesting for a given area.
3) Changing the direction of the sun for areas that are near each other, but separate. I've done this a lot...it can even be done where static lighting and lightmapping are being done. A good example is an area where the player passes through a series of caves. If the different outdoor areas between the caves look nicer if the sun is at a slightly different angle in each, you can change the direction of the sun while the player is in the cave. They won't notice that the sun is at a slightly different angle when they emerge from the cave on the other side.
4) Light Linking. Many engines support the ability to link lights to objects. This means certain lights might only be affecting certain characters, while other lights are linked to (and only affecting) other characters. Again, if this is handled correctly it's something the player will never notice.
