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Get to know your lighting
Lighting is the most important part of any graphical asset in a video game. Without proper lighting, even the most high definition textures and carefully modeled polygon characters/environments will simply look like crap. Lighting is what makes these beautifully designed games come to life.
There are just TWO types of lighting possible: direct and indirect. Each have their own sub-categories like soft, harsh, diffused, etc. But there are ONLY two! It's the mixture of these two which can provide a truly visceral experience.
Killzone 2 uses a multitude of lighting effects applied in real-time on a situation-by-situation basis. This is by far the most complex and impressive lighting engine created for a console video game. Everything you see in Killzone 2 is made possible by the lighting engine. If you turn it off, you will simply have a black screen - this is VERY important to remember. Most video games do not use this type of lighting because it's not only difficult to code - but uses an enormous amount of processing power.
The visibility in most games is attributed to only to the actual textures which are applied to objects in a game. Turn off the lighting in game X and you will still be able to see the room or area you're in. This is static and pre-canned environmental lighting. In Killzone 2, everything you see is affected by ambient and direct light sources. If there is no light source nearby... there is no light... you will not be able to see anything. The color of ANY level can be dynamically changed by the color of the lighting engine.
I've heard a LOT of complaints about "It's too GRAY!" from the E3 footage. Stupid people still exist! The level that was shown was under a looming thunderstorm... it's no wonder everything is drab and gray... because the SKY is drab and gray. This is how lighting affects the environment. Imagine a hot, sweltering day where the sun is beaming down on you hard: everything will be bright, possibly reddish or tan like a desert. That same scorching hot day can drastically change with the weather - thusly completely changing your environment and everything in it via AMBIENT lighting or Indirect lighting.
Examples
In no particular order:
Our first example of lighting is probably the most prominent in the game: Muzzle Flash. This occurs when firing any number of different weapons. This light is Direct with mixtures of soft, harsh, diffusion and color. The color will no doubt be affected by the type of weapon you are firing. Some may be orange-ish, some may be more fluorescent. Take a look at the picture below to see just how this uses direct/indirect lighting to not only change the Helghast in front of your gun, but the environment as well:
Aside from the Muzzle Flash - you will notice yet ANOTHER detail associated with firing a weapon: Muzzle Flare! I believe this is a replacement for the typical LENS FLARE effect we see in many games. This is being used instead because... HEY! We don't run around with cameras in our faces when we're in battle (that's just how we roll)... so why should we get lens flare? Take note in the next picture the purple flare effect you see when firing your weapon:
Impressed yet? Keep reading.
Next I'd like to show just how advanced and beautiful the Self-Shadowing is being done on players/enemies in Killzone 2. This uses a mixture of direct, soft and diffused lighting to help create shadows that are proper, SOFT (not jagged) and diffused. This is probably the most complex self-shadowing we have seen in a real-time game. Take special note that the characters do NOT use any Bump-Mapping for effect. All detail in clothing/armor are achieved through EXTREMELY high amounts of polygon detail: Note the subtleness of the diffusion being applied to both the lighting and shadows on this Mini-Boss and how it helps make his incredible detail simply "pop"!
Diffusion is one of the most impressive and realistic effects you can have applied in-game. This emulates exactly how real light would affect an object. Take a look at this example of diffusion: see how the muzzle flash is affecting the shattering box? The closer to the nozzle the wood fragments are - the brighter the light will be. Note how each individual piece of wood also affects the other fragments with indirect lighting - attributing to the stunning detail of proper soft shadowing!
Here's another great example of diffusion being used in conjunction with ambient lighting and proper self and soft shadowing. Take note in Sev's brow, cheek, lips and ridge of his nose. This is how ambient lighting being refracted off of the clouds will affect players/environments in Killzone 2.
Direct lighting is lighting that is being cast on a player/object in the environment from a specific light source such as a street light, desk lamp, candle, fire, etc. Take a look at this next example of a Helghast trooper underneath a light - note the incredible level of detail in his clothing that begins to "pop" simply from a few wrinkles:
This is probably my favorite example of how detailed and accurate the lighting engine in this game is. Someone (a hater) said in a post that the Helghast's masks aren't actually lit up - that they are simply textures - because such minute details don't need that much attention. Here's proof that this naysayer was DEAD wrong. Note how the goggles on this trooper's mask light up his SLEEVE and the shadowing that is being created on his face-mask and sleeve because of this light. ALSO take note of this incredibly small detail of INDIRECT LIGHTING: take a look at the front of the helmet... notice the ambient lighting coming from the sleeve of the trooper is affecting his helmet? Remember... his goggles are UNDERNEATH the brim of his helmet. Goggles shine on to sleeve - sleeve then reflects diffused lighting onto the helmet... IMPRESSIVE!
Explosions: Need I say more? Note how the light coming from the explosion is even affecting the air-duct and pipes underneath running just up and to the left of that poor Helghast who got his ass BLOWN TO SMITHEREENZ!
Lightning - Zeus commands it... now the Helghast do, too! Notice how this flash of lightning drastically changes the overall color of the environment. The fluorescent color of the lightning is what attributes to this environmental change. It also affects you (well... you can see your gun) and the Helghast. The color of the lightning is directly attributed to the color of the surrounding clouds - the fluorescence of lightning helps remove the muting typically associated with soft lighting. Fluorescent lighting is often noted as "Harsh" lighting because it is unnatural. Also take note how the lightning makes certain details of the cement curb "pop" like small holes and imperfections.
Let's take one last look at all of the lighting elements combined into a single shot. Note the direct, indirect, soft, ambient, harsh, colored and diffused lighting along with proper self, soft, and diffused shadowing.
The sequence of pictures at the end illustrated the drastic changes in the surface caused by different light sources. Not many games use that quantity of resources to only light and shadow.
Another feature is that lights have regions of illumination. These sources cast partial shadows in a limited field.
We have more than four or five sources of light emitters. There are global sources, partial sources that radiate small fields, flashes, fixed lights that display shadows projected in the floor in combination, and some sources behave like dimmers.
CREDITS TO Ninja-Matic and SantiagoFlores.
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