Rich, Thanks for the info. Now to figure out how to get Mapserver to do the calcs...
Thanks! Brent Fraser GeoAnalytic Inc. Calgary, Alberta ----- Original Message ----- From: "Richard Greenwood" <[EMAIL PROTECTED]> To: "Brent Fraser" <[EMAIL PROTECTED]> Cc: <MAPSERVER-USERS@lists.umn.edu> Sent: Monday, August 20, 2007 4:05 PM Subject: Re: How to calculate Azimuth from Angle in map file? > On 8/20/07, Brent Fraser <[EMAIL PROTECTED]> wrote: > > Mapservites, > > > > I've got shapefiles with angle values (0 degrees = > > positive X axis, increasing counter clockwise) but > > Mapserver uses azimuths ( 0 = positive Y axis, increasing > > clockwise) when rotating symbols. > > > > Is there any way to calculate azimuth from angle in the > > map file? I don't want to modify the dbf portions of the > > shapefile if I don't have to; there's 13,000 of them, and I > > may get updates so maintenance could be a pain. > > > > It would be nice if I could do something like: > > > > STYLE > > SYMBOL "pt_Building" > > ANGLE (90 - [angle]) # this doesn't work, so don't > > try it! > > COLOR 80 80 80 > > END > > > > Any ideas? > > > > Brent Fraser > > GeoAnalytic Inc. > > Calgary, Alberta > > Not sure if this will work in a map file, but the formula I use to > convert "mathematical" angles to azimuths is: > > azimuth = (450-m) - int( (450-m) / 360 ) * 360 > > where "m" is the "mathematical" angle. > > -- > Richard Greenwood > [EMAIL PROTECTED] > www.greenwoodmap.com
