Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!zaphod.mps.ohio-state.edu!julius.cs.uiuc.edu!apple!agate!shelby!neon!rokicki From: rokicki@Neon.Stanford.EDU (Tomas G. Rokicki) Newsgroups: comp.text.tex Subject: Re: tex dvi Previewer for Xwindows Message-ID: <1991Jan9.182924.1523@Neon.Stanford.EDU> Date: 9 Jan 91 18:29:24 GMT References: <139@dogmelb.dog.oz.au> Organization: Computer Science Department, Stanford University Lines: 22 >The previewer dvipage, which unfortunately runs only on SunView, >produces the crispest display I have seen. It substitutes spatial >resolution for grey scale resolution by passing the binary text image >through a low pass filter, creating a highly readable display. I know >that xdvi does not utilize such a filter and consequently its display >is inferior to dvipage. Does xtex employ such a trick? I've played with this idea on and off for the past five years. Unfortunately, at the low resolutions previewing is normally done at (72 to 150 dpi), the feature size of the characters is about the same size as the pixels being used to display them. Thus, using low-pass filtering tends to blur out the features, rather than reduce the ragged edges. In other words, low-pass filtering `blurs' the image, and my eyes at least get `frustrated' trying to focus on the characters. At resolutions of 300 dpi and above, low pass filtering does seem to make the display look better, but not many screens can show an entire page at 300 dpi. -tom