Lighting in XCOM-EU and games

Lighting in games 

Lighting is a very important part of games, as they help with the atmosphere that the game is trying to make. They can tension for making the environment too dark, or a very mystical feeling with many multicolored light sources. Lighting gives shadows, which helps tell players where they or other objects/ characters are in the scene. There are so many benfits of using lights correctly in today's games, but in order to understand how, we must look at what makes up lighting. Later we will look at how lighting is applied to XCOM: Enemy Unknown. 

Lighting, in games, is made of 3 parts, Ambient, diffuse, and specular lighting. 

Components of lighting

Ambient lighting- is the amount of lighting in scene and is from a non-directional light source. Generally tells the player if they are indoor, or outdoor, if it is day or night.
Diffuse lighting- is the reflection of the light from a surface, which is reflected at many angles rather than one, in the case of specular reflection below. This can show how powerful the light source is

Specular lighting is the use of bright spot highlights to give visual clues for light source locations. For example a red sphere with just ambient and diffuse lighting looks like the following:

Now if we add a white specular highlight we get the following result: 

Specular lighting is most commonly used to give light reflection off of metallic surfaces such as mirrors and highly polished/reflective metal surfaces. It is also used on other materials such as reflecting sunlight off of water. Used well it can add a degree of photo realism to most 3D scenes. All of this is from the source below www.rastertek.com/dx11tut10.html

Now we shall apply this to one of my favorite recent game, Xcom:Enemy Unknown! 

Xcom Gameplay

All my pictures are from the video provided in the link, about the introduction, and tutorial mission of XCOM: Enemy Unknown. Playing the tutorial mission of XCOM:EU, which was a pretty immersive experience, due to the fact it was taking place at night. After carefully examining each picture, we can see how lighting can affect the immersion of the game in each scene. How lighting can emphasize specific objects, or can convey a feeling to the players.

 This first picture takes place in the base of XCOM headquarters, right when we see the Xcom project being activated in the mission room. 

 The first picture seems to use a lot of diffuse but no specular, due to the fact there isn't metallic, or highly reflective surfaces. However there is a great amount of diffuse lighting from in this scene, as we can see with the huge amount of light reflected from the staff. This emphasizes how strong, and /or how close the light source, which in this case is a detailed hologram of the Earth. Important for the Xcom organization to monitor the state of the world, and lighting shows how important this globe is to XCOM.

This second picture also takes place in the base but focuses more on the soldiers, rather than the staffs. 

This shows specular lighting, with the metallic parts of the gun as the light source is probably in scene. Sure there is some diffuse here, but not as strong as the previous picture, showing how far the we are from a light source. What we should really focus on are the guns of the soldiers, which are affected by the specular lighting. If you notice, only the guns have specular lighting, but no the walls right beside it. Not only do the walls look more bland, but it draws your eyes more easily to the guns which will be used. This shows us how the omission of light/detail to nearby objects, can emphasize some objects in the scene.

The third and fourth picture takes place during the mission, where the soliders are outside during the mission in Germany. This is the first missions, and we are to meet up with an allied squad which seems to have gone missing.

As you can this takes place at night, greatly reducing brightness, and ambient lighting. However from a game designer's perspective, there may be some parts of the level, such as the detail on the dead soilder, which the designer might want the user to see well. For this the ambient has to be just right, too dark, and no details are visible, too bright, and it doesn't look like night.

Finally, during the mission, our squad goes inside to follow the radio sign which is being sent out. This radio signal seems to be from last surviving allied squad member, and we approach him in the picture below. 

The last solider of the allied squad is seen to be found to be in a state of unresponsiveness, however he is armed, and dangerous. In this picture our squad member approaches him however the only thing he says is "help me", suspiciously under the only spot light in the room . With this scene the ambient is turned down alot more the previous scene, and not just because we are indoors at night. This will make the soilder the focal point in the room, while increase the tension that player experiences, because we all know the darkness the hiting some secrets. Lack of lighting can obscure details, and this case the solider, and what is truely happening in this room. This obscurity, is what designers will use to add tension to games, especially when the player has just started the game.

Unfortunately what see is the solider is being mind controlled by some sort of alien creature, shown in the second picture. The situation quickly escalates as this becomes an alien ambush, and your first encounter with the extraterrestrial threat.

We can try to make out what this alien looks like, however the lack of lighting hides what the true identity of this creature is. We can make out with the lighting, that the alien is usual its head and hands to control the solider, due to its glowing appearance. There is no specular reflection, but that doesn't eliminate the fact it could have metal objects on it somewhere.

Also no diffuse lighting as maybe it isn't showing its true potential in this ambush.

In this case, ambient lighting is at its lowest, obscuring the whole alien darkness. This not only hides the alien's details, but it gives it that mysterious authority figure, like  the leader of the counsel of nations show earlier. All this obscurity will be haunt the player, until they truly can face this alien as a boss of a later level.

Applying the fundamentals of the lighting in games, from a game designers perspective, can truely enhance the game.Trying to implement the lighting is one problem for the engine designers, but properly using it in game would fit under the game designer's role. Hopefully we will see more games using light more effectively in the future, creating an immersive environment.