Hi, I'm hitting on the mosaic again. The issue this time is about trying to provide the background color seamlessly on irregular mosaic. You can find two images of what's happening now in the following screenshots:
http://jira.codehaus.org/secure/attachment/31467/mosaicBlackground.jpg http://jira.codehaus.org/secure/attachment/31465/mosaicTransparent.jpg The first and second are two slightly translated version of the same image, in the first a tile appears on the top and forces the black background color of the mosaic to appear, the second pans a little further and the top left tile gets out of the view, making the black background disappear. Now, in my understanding this is an artifact of how JAI mosaic operator and the mosaic plugin work: * the mosaic plugin loads only the tiles that are really necessary to show the view. This prevents some caching, but allows big mosaics of png/jpeg images to be displayed (the readers of these two formats load and keep the image with a strong reference, so building the full mosaic for a small area rending is not only inefficient, but not possible memory wise) * the JAI mosaic operator works only against the tiles it receives. Yet, from a user point of view the result is inconsistent, and it gets worse if tiled rendering is used (think OpenLayers), where depneding on where the rendered tile falls, you get patches of black or transparency. The problem seems simple enough, if no tile is loaded, the JAI Constant operator can be used to return a single color tile... I'm just not sure about what the geometry of the thing would be... where do I get the size and right color model for that constant image? Cheers Andrea ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Geotools-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-devel
