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