Club Amiga de Montreal - CAM/CAM_CD_1.iso/files/166.lha/demorun.doc

Text File | 1988-04-28 | 5.4 KB | 119 lines

    Hi,

    Here's a specialized XICON-like hack that will help some of you BADGE
    contest enterers to comply with some of the tougher constraints
    contained in the rules.

    The contest rules state that you should be able to drag your entire
    demo (in a drawer if necessary) as a single icon onto a hard disk and
    have it still work from either the workbench or CLI without any ASSIGNs
    or assumed disk names etc.

    This hack is particularly useful to Director owners who are using
    custom fonts or using the sound module, but may also be useful
    with any other programs having similar problems determining
    the name of the directory they are being run from.

    When using fonts included with your demo, or (in the Director) the
    sound module, someone has to tell the system where all the stuff is.

    Due to a bug (or is it a feature :-) in AmigaDOS Execute() system call
    (which the Director uses internally for its EXECUTE command), programs
    being EXECUTEd will always think they are being run from the root
    directory of DF0:, with no way to determine where the EXECUTEing demo
    is actually being run from.  This makes it virtually impossible to
    assign fonts to the directory you are running your demo from without
    making some assumptions as to the name of the disk on which the demo is
    contained etc.  Since this is in conflict with some of the suggestions
    in the BADGE contest rules, I put together this hack.

    This program is a small (6K) program with icon, that determines it's
    own directory, and does an ASSIGN HERE:  to that directory.  It will
    then search the tooltypes parameters in the icon for a string that
    starts with EXECUTE= .  It will do an Execute() call to run the
    program(s) (with parameters) specified by these EXECUTE= entries
    (multiple such entries are allowed).

    This example does an EXECUTE=projector here:demo.film  to run a Director
    animation.  The resultant animation can assume that HERE: is assigned
    to it's current directory, and specify that as the location of the
    FONTS: and the MOD: directory (for the sound module) with Director
    commands such as:

        EXECUTE a,"assign mod: here:options"
        MODULE "sound"
        PAUSE 20        :rem  delay to allow module to load without
                        :rem  disk contention.  (you could load other
                        :rem  stuff instead)
        EXECUTE a,"assign mod:"        :rem  unassign mod, don't need anymore
        ...(load sounds, play sounds, etc.)...

        EXECUTE a,"assign temp: fonts:"
        EXECUTE a,"assign fonts: here:fonts"
        ...(load fonts etc)...
        EXECUTE a,"assign fonts: temp:"
        EXECUTE a,"assign temp:"
        ...(setfont, etc.)...

    All other references to file names (picture,sound etc.) within the
    script should probably be done using HERE: for correct operation.

    Upon exit of the program, demorun will un-assign HERE: so the entry
    does not take up any memory (another contest rule is that demos will
    return all it's memory, a laudable goal).  You should remember that
    any ASSIGNs done in your script should before completion do an:

           ASSIGN TEMP:

    (for example to unassign temp) to undo any special assigns that have
    been done.  Ideally, if you have correctly undone all the assigns
    you can check this with the ASSIGN command from the CLI after running
    your demo and see if there are any outstanding assign entries that
    reference the disk that contains your demo.  If there are none, the
    disk icon should disappear after being removed from the drive, and
    you have correctly undone all that you have done during the demo.
    (*whew*).

    The icon also has a WINDOW= command in the tooltypes section of the
    icon (check this with the workbench "info" command after clicking
    once on the demorun icon).  This sets up an initial window which
    may be necessary for the programs being run if they output anything
    to the CLI window.  Without this window definition, such programs
    will crash.  This window feature makes the existance of the Projector
    icon completely unecessary.  You can change the window's title by
    changing the title string contained in the WINDOW= tooltypes
    parameter.

    Note that the stack parameter in the icon will only affect the stack
    for the demorun program itself, if you need to adjust the stack
    for the program you're running (shouldn't need to for the Projector)
    you'll have to do an:

        EXECUTE=execute here:script

    with a stack command in the script.  (I haven't tried this by the
    way).  This should use the execute AmigaDOS command to run a script
    file which can adjust the stack for programs executed by the script
    itself.  Any script output should still end up on the demorun window.

    This program will also run from the cli simply by typing it's name.
    I expect you may decide to re-name it to something more suitable for
    your demo, and  perhaps rework the design of the icon with an icon tool.

    As you may have surmised, with the Director doing both sound and
    custom fonts, you end up doing about 10 ASSIGN commands during the
    course of the demo.  Lot of thrashing, don't know if its really worth
    all that, but it is about the only way to completely meet the fine
    print of the terms of the BADGE contest.  Please let anyone you
    may know who is submitting a Director-based demo to the BADGE contest
    about this, time is getting short.

    Rest assured, future Directors will eliminate most if not all of
    such complications (if future AmigaDOS's don't do it for us).

    Keith Doyle 9/12/88
    213-325-1311 (7pm-12mid Mon-Thu)