Postprocessing effects in a 3d game are graphical effects applied to each frame of video after it has been completed in the per-pixel rendering stages. They allow for special effects that require knowledge of more than one pixel at a time.
Guild Wars Usage
In Guild Wars, these postprocessing effects are known to be used for various effects:
- Bloom: A brightening of the brightest spots in an image, bleeding or blurring them to allow the brightness to partially overpower the surrounding area. The brightest examples of this are:
- Desaturation: Draining the color from an image. Extreme applications result in black and white or sepia-type images; moderate usage just sucks the vitality from a scene. This is often seen in:
- Death. When you are dead, the color drains from your view.
- Mild desaturation can be used as part of the color control and finishing touches of a scene; this is harder to point out, but is one of the things that can cause an area to lose some of its feeling when postprocessing is disabled.
- Distortion: An advanced transparency effect that warps the image behind transparent objects to create heat distortion, ripples of magical power, and similar effects. As it is applied in postprocess, the edges of solid objects that are in front of the distortion effect will often be slightly warped by it as well.
- A frequent use of distortion is in the heat from large fires. There are a great many of these -- Deldrimor Beacon Fires, the bonfire in Yak's Bend, the great brazier in Eye of the North. The most accessible of these is the bonfire seen on the current Eye of the North themed Login/Character Select screens.
- The magical ripples in Nightfall and Eye of the North portals are created with distortion.
- Water: Some waterfalls, especially those that fall in open air as in Fenrir's cave in Norrhart Domains, use distortion to simulate the refraction of uneven moving water.