shadebob

shadebob

English

Etymology

shade +‎ bob. See bob (“blitter object, type of hardware sprite”).

Pronunciation

• Audio (UK)

  (file)

Noun

shadebob (plural shadebobs)

1. (demoscene, computer graphics) A type of bob (graphical sprite-like element) rendered additively on the display, so that it blends with others but can be easily removed again by decrementing the colour value at each pixel.
   • 1999, "JT Liimatta", The Party compo rules. (on newsgroup comp.sys.ibm.pc.demos)

     If I made a shadebob routine, which ran 60Hz on PentiumIII 550Mhz on 320x200x8bit mode, would you be impressed?

   • 2007, "[e-mail]", Why are shadebobs and 2d alpha blends so convincing? (on newsgroup comp.graphics.api.opengl)

     Even on older hardware, the dithering is perfect. The effect is convincing. You can press your face up against the screen and see no edges, you can see wonderful curves and strange shapes out of shadebobs that are probably unintentional.