[OpenMap Users] Code Submission

From: Thomas Schar <thomas.schar_at_dsto.defence.gov.au>
Date: Fri, 16 Jun 2006 15:22:19 +0930

Not sure if this can be done a different way, but I'm including source
for a very trivial layer that really just supports programmatic
addition/deletion of simple bitmaps to a layer. (Very similar to the
com.bbn.openmap.plugin.CSVTiledImagePlugin except that you can add files
in dynamically).

CVSTiledImagePlugin would have been fine for my requirements, except I
couldn't dynamically add images, and was restricted to using files to
load images. Perhaps, a refactor of CSVTiledImagePlugin would be better?
Perhaps something like, "GenericImagePlugin" and subclass
"CVSTiledImagePlugin"? (Where GenericImagePlugin allows programmatic
dynamic addition/deletion of images to the layer and CSVTiledImagePlugin
simply uses a constructor file property based initialisation?)

If it's worth doing, reply to this and I'll submit a proper patch.
Moreover, I'm looking into the OMScalingRaster to see if a pre-generated
mip mapped approach would be faster for 2d blits. (ie. for example, in
our instance, the 64MB OMScalingRaster takes a good 2 seconds to render
when zoomed out. I'm guessing this is due to having to blit the entire
thing down to a small area. A pre-generated mipmap would reduce the
data size to a small single digit percentage of the entire bitmap). If
it speeds things up, I'll submit a patch for this too.

Apologies if this is in the wrong area.


 * This class is a very naive implementation of a bitmap rendering
layer. It simply invokes
 * the generate methods of the OMScalingRaster instances contained. The
OMScalingRaster instances
 * do not (seem) to do any smarts with mip mapping, or hierarchical
tiled rendering.
 * _at_author txs
public class BitmapLayer extends OMGraphicHandlerLayer {
        ArrayList<OMScalingRaster> m_aryImgs=new
     * This adds an image to the layer and returns a handle to the image
     * _at_throws IOException
    public OMScalingRaster addImage(String strFilePath, LatLonPoint
latlonTopLeft, LatLonPoint latlonBotRight)throws IOException{
        File fileImg=new java.io.File(strFilePath);
        FileInputStream fisImg=new FileInputStream(fileImg);
        FileCacheImageInputStream fciis = new
FileCacheImageInputStream(fisImg, null);
        BufferedImage bufImg = ImageIO.read(fciis);
        OMScalingRaster rasterImg=new
OMScalingRaster(latlonTopLeft.getLatitude(), latlonTopLeft.getLongitude(),
         latlonBotRight.getLatitude(), latlonBotRight.getLongitude(),

     * Removes the specified OMScalingRaster image from the layer if it
has been added
     * _at_param rasterImg
    public void removeImage(OMScalingRaster rasterImg){
    /* (non-Javadoc)
     * _at_see com.bbn.openmap.layer.OMGraphicHandlerLayer#prepare()
    public synchronized OMGraphicList prepare(){
        OMGraphicList list=super.prepare();
        Projection proj=getProjection();
// iterate through the entire array
            list=new OMGraphicList();
        for(int iImg=0; iImg<m_aryImgs.size(); ++iImg){
            OMScalingRaster rasterImg=m_aryImgs.get(iImg);

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Received on Fri Jun 16 2006 - 01:56:33 EDT

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