Hi all, I am encountering some odd results with tiled WMS requests for raster layers. When zoomed in on a raster layer, the edges of the tiles appear to be being clipped, resulting in horizontal and/or vertical strips and wedges of no data (gaps) along the tile borders. The issue occurs when the WMS default interpolation method for the raster layer is set to bilinear or bicubic (nearest neighbour is ok) and the requested CRS is different to the declared CRS of the layer (i.e. GeoServer is reprojecting the data to produce the tiles). Adjusting the metatiling factor and gutter size has no appreciable effect.
There seems to be a correlation between the cells size of the raster dataset and the zoom extent at which the issue starts to occur - the smaller the cell size the further you have to zoom in to see the problem. The issue can be repeated with the Spearfish elevation demo layer that ships with GeoServer by viewing the layer in a web map client able to make tiled requests (e.g. QGIS or GeoServer's built in OpenLayers client), setting the request CRS to something other than EPSG:26713, e.g. 4326, and zooming into a scale of around 1:1000 or less and panning around. The issue appears to have been introduced in version 2.16.1 and later, doesn't happen in 2.16.0. Tested on Windows 10/Oracle JRE 1.8.0_281 and Ubuntu 18.04.5 LTS/OpenJDK 11.0.10. This is a bit of a problem for us as we have national scale raster datasets with coarse cell sizes and discrete classifications that need to be smoothed using bilinear interpolation to be presentable in our portal, and unfortunately the user doesn't have to zoom in very far before the strips and wedges become apparent. Could I be missing something in the GeoServer settings? Any advice would be much appreciated. Regards, Aaron Sedgmen. Geoscience Australia Disclaimer: This e-mail (and files transmitted with it) is intended only for the person or entity to which it is addressed. If you are not the intended recipient, then you have received this e-mail by mistake and any use, dissemination, forwarding, printing or copying of this e-mail and its file attachments is prohibited. The security of emails transmitted cannot be guaranteed; by forwarding or replying to this email, you acknowledge and accept these risks. _______________________________________________ Geoserver-users mailing list Please make sure you read the following two resources before posting to this list: - Earning your support instead of buying it, but Ian Turton: http://www.ianturton.com/talks/foss4g.html#/ - The GeoServer user list posting guidelines: http://geoserver.org/comm/userlist-guidelines.html If you want to request a feature or an improvement, also see this: https://github.com/geoserver/geoserver/wiki/Successfully-requesting-and-integrating-new-features-and-improvements-in-GeoServer [email protected] https://lists.sourceforge.net/lists/listinfo/geoserver-users
