Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    Re: Cap'n tips
    From: Steven Tripp
    Date: 1999 Feb 14, 7:37 PM

    Rick Emerson wrote:
    > One quirk I did see repeatedly is a loss of centering when using
    > "intellegent zooming".  This feature which is very useful keeps
    > selecting the most appropriate scale chart for the area being
    > displayed.  If, for example, you're looking at a 1:40000 chart and
    > want to zoom down to get a close look at a feature and a 1:20000 chart
    > covers the area, this chart is brought up automatically.  Conversely,
    > zooming out will invoke the next smaller scale chart (e.g., 1:80000).
    > When zooming in, however, occasionally the center of the new, larger
    > scale (smaller area) chart is no longer anywhere near the center used
    > with the previous chart.  I was looking at the Portland, ME area and
    > zoomed in to look at Peaks I but found myself looking at a spot well
    > to the southwest of there.  I'm not sure *why* this happens and will
    > accept it may well be an error on my part but it can be frustrating on
    > occasion.
    I'm not sure how the Cap'n works, but some of these nav programs do raster maps
    in this way:  They break up maps into small rectangles for storage and load
    several (9?) pieces and join them seamlessly on screen.  When you zoom in or
    out, it takes the clickpoint and tries to find a rectangle at the higher or
    lower scale and then loads it at the center and loads its surrounding pieces.
    If your click occurs right on an (invisible) boundary the computer won't know
    which rectangle to load to the center.  On the other hand maybe the programmer
    made a mistake in labeling the rectangles.
    Incidently, I am rewriting my Mac navigation program for Windows and UNIX and
    would be interested in suggestions for features.
    > --
    Steven D. Tripp        +-------------------------------------------+
    University of Aizu     |+-----------------------------------------+|
    Aizu-Wakamatsu, Japan  ||     Lat 39.5 N  Long 140 E  GMT +9      ||
    tripp@u-aizu.ac.jp     |+-----------------------------------------+|
    fax +81-242-37-2599    +-------------------------------------------+
    =-=  TO UNSUBSCRIBE, send this message to majordomo@roninhouse.com:     =-=
    =-=      unsubscribe navigation                                         =-=

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site