Using lights and cookie textures to simulate a cloudy day
As it can be seen in many first-person shooters and survival horror games, lights and shadows can add a great deal of realism to a scene, helping immensely to create the right atmosphere for the game. In this recipe, we will create a cloudy outdoor environment using cookie textures. Cookie textures work as masks for lights. It functions by adjusting the intensity of the light projection to the cookie texture's alpha channel. This allows for a silhouette effect (just think of the bat-signal) or, as in this particular case, subtle variations that give a filtered quality to the lighting.
Getting ready
If you don't have access to an image editor, or prefer to skip the texture map elaboration in order to focus on the implementation, please use the image file called cloudCookie.tga, which is provided inside the 1362_06_01 folder.
How to do it...
To simulate a cloudy outdoor environment, follow these steps:
In your image editor, create a new...
