Hello
I have WMS layers set up in GeoServer that uses SLD¹s with ExternalGraphic
links to PNG images. When I produce WMS GetMap images, the icons are a lot
blurrier (antialiased) than they are in the original image. The SLD
declares the icons' native size.
What are the options to control antialiasing of external icons in WMS
images? And is there a way to get exact pixel copy from source image (icon
file) to target image (WMS map) when the icons use the correct size?
I¹m also noticing that the blurriness varies with the zoom level from
very blurry, quite blurry, and exactly the same as the source image. The
SLD doesn¹t have scale differences. It leads me to the theory that the
icons are drawn at some fractional pixel. If this is the case, is there an
option to fix ExternalGraphics to the nearest whole pixel?
Kind Regards,
Thomas Jahnsen
Nordeca AS
thomas.jahnsen@anonymised.com
On Thu, Apr 3, 2014 at 2:56 PM, Thomas Jahnsen
<thomas.jahnsen@anonymised.com>wrote:
Hello
I have WMS layers set up in GeoServer that uses SLD¹s with ExternalGraphic
links to PNG images. When I produce WMS GetMap images, the icons are a lot
blurrier (antialiased) than they are in the original image. The SLD
declares the icons' native size.
What are the options to control antialiasing of external icons in WMS
images? And is there a way to get exact pixel copy from source image (icon
file) to target image (WMS map) when the icons use the correct size?
I¹m also noticing that the blurriness varies with the zoom level from
very blurry, quite blurry, and exactly the same as the source image. The
SLD doesn¹t have scale differences. It leads me to the theory that the
icons are drawn at some fractional pixel. If this is the case, is there an
option to fix ExternalGraphics to the nearest whole pixel?
There are no options in older versions, but 2.5.0 rounds the location to
the nearest
whole pixel by default (unless the icon is rotated in the SLD, because in
that case resampling
is going to happen anyways)
Cheers
Andrea
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