Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!rutgers!aramis.rutgers.edu!remus.rutgers.edu!declan From: declan@remus.rutgers.edu (Declan McCullagh/LZ) Newsgroups: comp.sys.next Subject: Re: Color NeXTStation Summary: Alpha Channel Message-ID: Date: 7 Nov 90 21:36:15 GMT References: <85720@tut.cis.ohio-state.edu> <1990Nov7.203557.10442@athena.mit.edu> Organization: Rutgers Univ., New Brunswick, N.J. Lines: 23 In article <1990Nov7.203557.10442@athena.mit.edu>, portnoy@athena.mit.edu (Stephen L. Peters) writes: > In article declan@remus.rutgers.edu (Declan McCullagh) writes: > >Not much. Believe it or not, PostScript drawing/moving windows, etc. > >is quite fast on the NeXTstation Color. PostScript also wins here, > >too: dithering a 24-bit image looks almost as good as it does on the > >NeXTdimension - it's hard to tell them apart unless you know what to > >look for. Even resizing a color image is quite fast. > > I have another question about the color computer. I've heard that the > 16-bit color is 12 bits of color, and four bits of alpha channel. I > assume that this means 3 bits each or red, green, and blue, but I'm > not sure what the "alpha" is -- some type of transparency effect? Actually, there are four bits per RGB color, yielding 12 total. That gives you a fixed palette of 4,096 colors. The missing four bits are used for an alpha, or transparency channel ("monochrome" NeXT products also have a 2 bit/pixel alpha channel). While not incredibly exciting on a monochrome system, it's quite remarkable on a color system... -------------------------------------------------------------------- Declan McCullagh / NeXT Campus Consultant \ declan@remus.rutgers.edu --------------------------------------------------------------------