Shader Effects
The pixel shaders of the graphics cards enable even more special effects that simplify the life of the gamer and are even important for survival in many situations. One area is the simulation of night vision goggles and the infrared light due to a heat sensing camera. In Splinter Cell, for example, you must trace the infrared signatures of mines or recognize residual heat on a panel of buttons in order to uncover the right access code.
Physical injury and poisonous gas cannot be felt, tasted or smelled—not on the PC nor in a movie—so these dangers require optical or acoustic signaling. One method of showing injury is that vision becomes less focused as the character has tears in his or her eyes, bones crack, or the character coughs in pain. In addition, the screen turns red, and the stronger the coloring, the more serious the injuries. In multi-player shooter games this is sometime unfair, as you are unable to get away under heavy fire, and lose orientation due to the changed color.
If a character is drugged, poisoned, or has simply drunk too much vodka, the world begins to swim and you see everything twice. At high concentration levels, it is possible to create tunnel vision in which you can better fix the target.
If a character turns into a demon, the environment changes, and enemy creatures are highlighted more. Of course this is difficult to check, as in the real world one rarely gets the chance to change into a prince of hell.
