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<DIV><SPAN class=776213113-09032009><FONT face=Arial color=#0000ff size=2>BIll,
</FONT></SPAN></DIV>
<DIV><SPAN class=776213113-09032009><FONT face=Arial color=#0000ff
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<DIV><SPAN class=776213113-09032009><FONT face=Arial color=#0000ff size=2>By
adding '&map.imagecolor=255+255+255' to your URL string, you will change the
background color to white. At least for MapServer versions of 5.2 or
greater. The trick will just be to keep track of the map scale in your
client and add the imagecolor substitution at the appropriate
scales.</FONT></SPAN></DIV>
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size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=776213113-09032009><FONT face=Arial color=#0000ff
size=2>David.</FONT></SPAN></DIV>
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<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left><FONT
face=Tahoma size=2>-----Original Message-----<BR><B>From:</B>
mapserver-users-bounces@lists.osgeo.org
[mailto:mapserver-users-bounces@lists.osgeo.org] <B>On Behalf Of </B>Bill
Thoen<BR><B>Sent:</B> Monday, March 09, 2009 9:12 AM<BR><B>To:</B>
mapserver-users@lists.osgeo.org<BR><B>Subject:</B> [mapserver-users] Change
Background Image Color Dynamically<BR><BR></FONT></DIV><FONT face=Georgia>I've
got a layer of USGS DRG's where I set the OFFSITE parameter to black to hide
the excess bitmap at the edges of the DRGs. But this also makes black lines ,
text and other black graphic elements IN the map as transparent, washing them
out. So I set IMAGECOLOR to black to sharpen them up. <BR><BR>However, at
scales beyond those appropriate for the DRGs I want to set the background
color back to white. So is there some way that I can either use a black
background only when the DRG layer is visible, or dynamically change the
background color as the map scale changes?<BR><BR><BR>TIA,<BR><BR>- Bill
Thoen<BR></BLOCKQUOTE></FONT></BODY></HTML>