Decimal degree units

[Brent Fraser]

Chris, (and all),

  I haven't tried the shapefile indexing using shpindex
(my comments in the original email weer about the
tiling method supported by mapserver), but I'll have
a look at it this week...

Brent

----- Original Message -----
From: <imap at chesapeake.net>
To: Brent Fraser <bfraser at digitalscience.com>
Cc: <mapserver-users at lists.gis.umn.edu>
Sent: Saturday, August 28, 1999 2:47 AM
Subject: Re: Decimal degree units


>
> Brent, Hi... Along these lines, have you tried to index shapefiles
> under WinNT?   I have never been able to get shpindex to work
> while compiled with MSC6.0.  No errors or anything, but when I
> index a shapefile, that layer no longer displays at all.
> I was just wondering if you had actually gotten this to work.
>
> Thanks,
>
> -Chris (imap at chesapeake.net)
>
>
> Brent Fraser wrote:
> >
> >   I've made mapserv a memory resident component  using Windows NT,
> > ActiveX and Active Server Pages.  And I use PROJ4 to project on the
> > fly.  But as Steve pointed out in a previous email, the most significant
> > tuning thing you can do is shapefile indexing.  Tile the shapefiles (if
> > they aren't already) and make an index shapefile for them.
> >
> >   Also, selectively display shapefiles based on scale if you've got a
> > couple of different scales of data (eg 1:1m DCW, and Tiger).
> >
> > Brent Fraser
> >
> > ----- Original Message -----
> > From: Rob Atkinson <rob at socialchange.net>
> > To: <cshorte2 at csc.com>
> > Cc: <mapserver-users at lists.gis.umn.edu>
> > Sent: Thursday, August 26, 1999 6:20 PM
> > Subject: Re: Decimal degree units
> >
> > >
> > >
> > > cshorte2 at csc.com wrote:
> > >
> > > > > I'll try the PROJ.4 support, but I'm guessing that the performance
hit
> > will
> > > > > kill me. Some of my maps have thousands of shapes on several
layers.
> > > >
> > > > Rob Atkinson did some work on performance of PROJ.4 and reckoned it
> > added 20% to
> > > > 30% to the total processing time.
> > > >
> > > > Cameron.
> > >
> > > FYI: This was on a shapefile about 20Mb in size, with highly detailed
> > polys. Maybe
> > > the fixed overheads of file IO are significant.
> > > Having a memory resident server rather than a CGI would be the single
> > biggest
> > > performance boost I think.
> > >
> > > --
> >
> --------------------------------------------------------------------------
> > ------
> > > Rob Atkinson
> > rob at socialchange.net
> > > Director                                                        Mob
0419
> > 202 973
> > > Social Change Online Pty Ltd                                Ph  +61
> > (2)9557 6500
> > > http://online.socialchange.net                              Fax +61
> > (2)9519 8940
> > >
> > >
> > >
>