Drobe :: The archives
About Drobe | Contact | RSS | Twitter | Tech docs | Downloads | BBC Micro

Reply to thread


PDF is NOT a Turing-complete programming language. One of the main reasons for creating the PDF format is precisely that this "feature" of PS was considered a bad idea. PDF is a static description.

Secondly, PDF is by no means a variant of PostScript targetted towards on-screen viewing. PDF has been designed for all sorts of target devices: professional printing devices, pre-press work and also for on-screen viewing, but the latter is no more the focus of PDF than any other target. You could call PDF an extensible, object-based, static (i.e., NON-Turing-complete) variant of PostScript with additional structure imposed to allow random access to objects. If Adobe were to design it today, I doubt it would look much different.

PDF could be called less static than Draw (because it does not require each and every attribute to be specified for each object, but instead keeps a "current graphics state"), but the contents of a PDF page are still a sequence of graphical objects, just like a Draw description. It is also significantly more complex than Draw, simply because it does so much more and needs to support all sorts of professional printing features. Finally, it is stream-based, which makes it more difficult to manipulate, but this is the price you pay for all the flexibility.

 is a RISC OS Userwuerthne on 5/9/05 12:44PM
[ Reply | Permalink | Report ]

Please login before posting a comment. Use the form on the right to do so or create a free account.

Search the archives

Today's featured article

  • Jan Vibe: The interview
    The man, the myth, the BASIC graphics master
     9 comments, latest by harmsy on 17/8/07 3:50PM. Published: 11 Aug 2007

  • Random article

  • Setting up a Windows firewall for Omniclient
    How to get AVG Internet Security working with RISC OS
     Discuss this. Published: 7 Jul 2007

  • Useful links

    News and media:

    Top developers:
    RISCOS LtdRISC OS OpenMW SoftwareR-CompAdvantage SixVirtualAcorn

    CJE MicrosAPDLCastlea4X-AmpleLiquid SiliconWebmonster


    RISCOS.org.ukRISCOS.orgRISCOS.infoFilebaseChris Why's Acorn/RISC OS collectionNetSurf

    Non-RISC OS:
    The RegisterThe InquirerApple InsiderBBC NewsSky NewsGoogle Newsxkcddiodesign

    © 1999-2009 The Drobe Team. Some rights reserved, click here for more information
    Powered by MiniDrobeCMS, based on J4U | Statistics
    "We incurred the wrath of Chris Williams, the main journalist at Drobe, who told us to 'Take our filthy spam and shove it where the sun doesn't shine'"
    Page generated in 0.0388 seconds.