Wouter Schaubroeck ha scritto: > Hi list, > > I read this interesting page: > http://geotools.codehaus.org/Rendering+Optimization about rendering > optimization, and was wondering, how far this actually got > implemented. What is implemented in Geotools and what not? > It's because I've made actually one implementation of optimized > rendering for points with geotools (kinda udig style), and it's > working very well! Some technical details can be found here: > http://conference.osgeo.org/index.php/foss4g/2008/paper/view/340/196 > (PDF).
Very interesting. I'm wondering how easy is to generalize. Certainly we can setup a 1 pixel width grid and light up pixels as points hit them, but what about non trivial styling, labels and the like? The optimization must be smart enough to handle all possible point styles the user throws at it (and eventually disable itself if it cannot handle the current style). For example, what if you wanted to colour each lighting with a different color based on its magnitude (don't know if it makes any sense, but if not, think of any point located variable that has an attribute that can be used to drive color), in that case what do you do? The grid should probably contain not only the fact that there's a point there, but also what is the "most interesting" (supposedly, the highest) value that occurred in it. > I'm working on a optimization for displaying linestrings (and perhaps > polygons), based on generalization. But that is still a work in > progress. The current streaming renderer does exactly that, generalization on the fly before rendering. To get better performance you should keep an in memory cache of the generalized geometries I guess. Anyways, I may be missing something. What's your approach, in detail? > If you guys are interested, I'd like to integrate my code with the > geotools code, but honestly, I don't know how this has to be done, are > there some procedures you have to follow, or can i just send my code > to somebody? Let's talk more in detail about it. Then you can attach patches to Jira. Quite frankly for these cases I'd like to see a renderer much like uDig one, layered, so that each layer can use its own specific rendering strategy (so your approach could be used only if the data and styles used make sense for it). I know there is a renderer like that in the works at Geomatys, but for contractual reasons they cannot open its sources just yet. That renderer should have the renderer per layer approach, and I still have a tiny hope that we can use StreamingRenderer as a singe layer renderer inside that framework (and add renderers such as yours as specific layer renderer instead). That is, provided it's not too hard to back port it to java5. Anyways, in the meantime we can talk about your work and a possible merge with the StreamingRenderer (which I help to maintain), with time we'll see if it's possible to merge everything with Geomatys work of if we'll have to roll a new multilayer renderer for GeoTools. Cheers Andrea -- Andrea Aime OpenGeo - http://opengeo.org Expert service straight from the developers. ------------------------------------------------------------------------------ SF.Net email is Sponsored by MIX09, March 18-20, 2009 in Las Vegas, Nevada. The future of the web can't happen without you. Join us at MIX09 to help pave the way to the Next Web now. Learn more and register at http://ad.doubleclick.net/clk;208669438;13503038;i?http://2009.visitmix.com/ _______________________________________________ Geotools-gt2-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
