Decimal degree units

[Brent Fraser]

  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
>
>
>