Display Image over map layer in GeoServer

Question

Hi

I am newbie when it comes to GeoServer and trying to figure out if there is an easy way to display images on top of map layer.

A background: In my application, based on a search criteria, some polygons are drawn on the map. Each polygon has a corresponding image (in TIFF format) that is stored somewhere. I want to load the image on top of the map when the user zooms in to a certain zoom level.

I know this can be done using openLayers but since my images are in TIFF format, (openLayers is not able to render TIFF images as far as i know) i have to convert them to .PNG first which would be very slow considering the number of images i have.

Hence I was wondering whether it would be possible to create a image layer that would retrieve an image of a certain polygon at a certain zoom level. If so, could anyone point me to an example or give me an idea on whether this is possible.

I am using spring 2.5, tomcat 5, java 1.6 and geoserver 2.0

Thanks.

Answer 1

GeoServer's styling language, SLD, supports using an image file to provide the fill texture when rendering polygons. If the number of polygons that you want to handle is small, you could just set up a style rule for each polygon with its own image URL for the fill. Otherwise, I'd recommend establishing a formulaic mapping from data attributes to image URLs, and using GeoServer's dynamic symbolizer feature to reference the images.