Full screen effect
A full screen effect (also known as a fullscreen effect) is a graphics technique that is applied to the entire screen, usually in postprocessing stage. These effects are often used in real-time applications such as video games or demoscene demos.
Examples of full screen effects are:
- Depth blur (aka Depth of field, Focus Blur, Lens blur): Recreates an effect caused by the optics of a lens. Images formed through a lens are in correct focus only when the subject is directly at a certain distance (the focal plane). Objects nearer or farther blur. Often recreated in games by blurring the frame buffer to a temporary texture, and drawing over the frame buffer with that blurred version, alpha blending based on the depth of the scene.
- Depth fog: Similar to Depth Blur, however a fog color is applied to the temporary texture.
- Motion blur: The previous frame (or an accumulation of previous frames) is blended over the current frame
- Motion trail:
- Static blur: The current frame is blurred. Variations include directional blurs, radial blurs, etc.
- Full screen bloom: A copy of the frame is modified such that only bright portions remain. The image is blurred, and then added back over the frame buffer. The result is that bright objects become brighter yet (though not beyond the point of luminance clipping), and bleed the color onto neighboring pixels
- Material bloom: Blooming is performed as described above, except that only portions of the screen are permitted to bloom. This can be done by flagging the stencil buffer when rendering any object permitted to bloom.
- Cross fade: Two scenes are rendered, and the final displayed image is a blend between the two.
- Screen distortion: The frame buffer is rendered back upon itself, but distorted. There are many different distortions possible, such as pinching the image towards the center of the screen.
- Heat haze: A blurred and wavy distorted version of the frame buffer is drawn back onto the frame buffer as a texture for objects representing Heat Haze.
- Color filters: The color of the image can be changed. Common examples are: black and white, inverse, sepia, and night vision.
- High dynamic range rendering and tone mapping: Often combined with blooming and other effects, this allows a scene which has been rendered in high dynamic range to be remapped to a low dynamic range display device.