Ciao Juirgen, please read below.... On Thu, Oct 9, 2008 at 12:45 PM, Jürgen Jacob <[EMAIL PROTECTED]> wrote: > Dear Simone, > thanks for your help! > > I get the image directly from the uDig Renderer: > ApplicationGIS.getActiveMap().getRenderManager().getImage()
There should a similar method to get the associate grid-to world transform and or the envelope. In basence of the grid to world, you can build it using the envelope. You can ask that to the udig guys. > > Additionally I'm no expert in the Geo world... and the word "georectified" > is confusing me. Does it mean that we have cartesian coordinates with > equidistant scale? It means that there exists an affine transformation that maps from the raster space (row columns) to the geographic space (lon,lat or easting, northing or whatever it is :-) ) > > If I can guarantee that there will be always a Rectangular projection with > equidistant lat / lon values, then it would be quite easy to calculate the > new coverage. > > But the user can chose arbitrary crs in uDig and I'm not sure if this can > lead to rotation, skew or axis seap (what's that? cant find a german > translation..). Your grid to world should be a simple scale and translate. Simone. > > Jürgen > > Simone Giannecchini schrieb: >> >> Ciao Jurgen, >> there is a missing piece here that it's needed in order to do >> transformation. I am talking about the grid-to-world transform which >> is the transformation that maps from raster space into model >> (geographi space). Assuming your raster is georectified this is a an >> affine transform. >> >> If you are getting this snapshot from the udig view you should able to >> get the gridtoworld from there and then, with some fiddling, to apply >> that to your coverage bounds. >> >> If your original coverage does no have any rotation or skew or axis >> seap you can rebuild the original grid-to-world as a simple scale and >> translate using the envelope and dimensions of the raster. >> Then you need to apply this transformation to the new raster >> dimensions to get the new envelope. Notice that the new raster >> dimensions must fall within the old raster dimension for this to work, >> which means that while cropping you need to retain the positions with >> respect to the original raster. >> >> Simone. >> >> On Thu, Oct 9, 2008 at 10:55 AM, Jürgen Jacob <[EMAIL PROTECTED]> wrote: >>> >>> Dear all, >>> I'm using uDig for my own application and have this problem: >>> The operator can make snapshots of the map for usage outside of the GIS >>> component of my application. The image (AWT Raster) is saved together >>> with envelope details (crs, min and max x and y). With a tool the user >>> can trim (crop?) this image inside the appliction. Example:Only a >>> certain part of the map / image is of interest. >>> Besides saving the new raster (quite easy) I must modify the saved >>> envelope values and here I need some help. >>> >>> I have the old Raster and a new Raster that is a part of old Raster. How >>> is it possible with geotools or jts to calculate the new bounding box. I >>> have the old bounding box and new and old raster dimensions. >>> >>> Thanks for your help!!! >>> > > > -- ------------------------------------------------------- Eng. Simone Giannecchini GeoSolutions S.A.S. Owner - Software Engineer Via Carignoni 51 55041 Camaiore (LU) Italy phone: +39 0584983027 fax: +39 0584983027 mob: +39 333 8128928 http://www.geo-solutions.it http://www.geo-solutions.it/simone.giannecchini http://www.linkedin.com/in/simonegiannecchini ------------------------------------------------------- ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Geotools-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-devel
