package GribView; import java.awt.Color; import java.io.ByteArrayInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.lang.Math; import java.rmi.RemoteException; import javax.swing.JFrame; import visad.ConstantMap; import visad.DataReferenceImpl; import visad.Display; import visad.FlatField; import visad.FunctionType; import visad.Linear2DSet; import visad.RealType; import visad.RealTupleType; import visad.ScalarMap; import visad.VisADException; import visad.java3d.DefaultRendererJ3D; import visad.java3d.DisplayImplJ3D; import visad.java3d.DisplayRendererJ3D; import net.sourceforge.jgrib.BitInputStream; import net.sourceforge.jgrib.GribFile; import net.sourceforge.jgrib.GribRecord; import net.sourceforge.jgrib.GribRecordBDS; import net.sourceforge.jgrib.GribRecordBMS; import net.sourceforge.jgrib.GribRecordGDS; import net.sourceforge.jgrib.GribRecordPDS; import net.sourceforge.jgrib.GribRecordIS; import net.sourceforge.jgrib.GribRecordLight; import net.sourceforge.jgrib.NoValidGribException; import net.sourceforge.jgrib.NotSupportedException; public class GribTest { private JFrame jframe; private Color colour = Color.white; private DisplayImplJ3D display; private DisplayRendererJ3D displayRenderer; private GribFile gribFile; private float minValue = 1.0e19f; // Store minimuim value of Grib data private float maxValue = -1.0e19f; // Store maximuim value of Grib data public GribTest() throws VisADException, RemoteException { // Specify the name of the file containing the GRIB data String fileName = "test.grib"; GribRecord gribRecord = null; // Create a GribFile with this filename try { gribFile = new GribFile(fileName); // Read in the first record gribRecord = gribFile.getRecord(1); } catch (FileNotFoundException e) { System.out.println (e + " in file " + fileName); e.printStackTrace(); } catch (IOException e) { System.out.println (e + " in file " + fileName); e.printStackTrace(); } catch (NoValidGribException e) { System.out.println (e + " in file " + fileName); e.printStackTrace(); } catch (NotSupportedException e) { System.out.println (e + " in file " + fileName); e.printStackTrace(); } // Define the domain - (latitude, longitude) RealType latitude = RealType.Latitude; RealType longitude = RealType.Longitude; RealTupleType domainTupleType = new RealTupleType(latitude, longitude); // Get the geographical range of the grid double[] range = getExtremePoints(gribRecord.getGDS()); int xVals = gribRecord.getGDS().getGridNX(); int yVals = gribRecord.getGDS().getGridNY(); // Create a linear 2D set with containing the latitude/longitude // coverage of the grid Linear2DSet domainSet = new Linear2DSet( domainTupleType, range[1], range[0], yVals, range[2], range[3], xVals); // Define the RealType of the range - RGB RealType rgbType = RealType.getRealType("RGB"); // Define the function type - (latitude, longitude) -> RGB FunctionType functionType = new FunctionType(domainTupleType, rgbType); // Define a flat field with this function and domain set FlatField gribField = new FlatField( functionType, domainSet); // Get the actual data values from the grib record float [][] flatSamples = getSamples(gribRecord); // Set the flat field to contain these values gribField.setSamples(flatSamples ,false ); // Create a data reference with this flat field DataReferenceImpl dataReference = new DataReferenceImpl("RGBDataRef"); dataReference.setData(gribField); // Set up the display display = new DisplayImplJ3D("Grib View"); displayRenderer = (DisplayRendererJ3D)display.getDisplayRenderer(); displayRenderer.setBoxOn(false); // Make latitude map to Y axis, and longitude to X axis ScalarMap latMap = new ScalarMap( latitude, Display.YAxis ); ScalarMap lonMap = new ScalarMap( longitude, Display.XAxis ); // Set the range to cover the area of the GRIB field latMap.setRange(range[1], range[0]); lonMap.setRange(range[2], range[3]); // Set the RBG scalarType to map to Display.RGB ScalarMap rgbMap = new ScalarMap( rgbType, Display.RGB ); // Set the range to cover the range of data rgbMap.setRange(minValue, maxValue); // Add the scalarmaps to the display display.addMap( latMap ); display.addMap( lonMap ); display.addMap( rgbMap ); // Configure the RGB constant map ConstantMap[] constantMap = { new ConstantMap(colour.getRed()/255.0f, Display.Red), new ConstantMap(colour.getGreen()/255.0f,Display.Green), new ConstantMap(colour.getBlue()/255.0f, Display.Blue), new ConstantMap(0.0, Display.ZAxis) }; DefaultRendererJ3D dataRenderer = new DefaultRendererJ3D(); // Add the data reference to the display display.addReferences(dataRenderer, dataReference, constantMap); // Create a JFrame to contain the display jframe = new JFrame ("Grib Test"); jframe.setSize(600, 500); jframe.getContentPane().add(display.getComponent()); jframe.setVisible(true); } /** * Find the extreme north, south, east and west points */ private double[] getExtremePoints (GribRecordGDS gds) { double[] range = new double[4]; switch (gds.getGridScanmode()) { case 0: range[0] = gds.getGridLat1(); // North range[1] = gds.getGridLat2(); // South range[2] = gds.getGridLon1(); // West range[3] = gds.getGridLon2(); // East break; case 64: range[0] = gds.getGridLat2(); // North range[1] = gds.getGridLat1(); // South range[2] = gds.getGridLon1(); // West range[3] = gds.getGridLon2(); // East break; } if (range[2] > range[3]) range[3] += 360.0; return range; } /** * Extract the data values from the binary data section of a GRIB * record. Return them as a 2-D array of floats */ private float[][] getSamples (GribRecord gribRecord) { int xVals = gribRecord.getGDS().getGridNX(); int yVals = gribRecord.getGDS().getGridNY(); int scanMode = gribRecord.getGDS().getGridScanmode(); float decimalScale = gribRecord.getPDS().getDecimalScale(); float mdi = gribRecord.getBDS().UNDEFINED; float [] values = gribRecord.getBDS().getValues(); float [][] flatSamples = new float[1][xVals*yVals]; float scale = (float)Math.pow(10.0f, decimalScale); float sample = 0.0f; // Loop over each column of target 2d array for (int c = 0; c < xVals; c++) { // Loop over each row of target 2d array for (int r = 0; r < yVals; r++) { // The order of the data within the array is // indicated by the scanmode, // must put a seperate entry here for each scan // mode so that each possible order is // catered for switch (scanMode) { case 0: sample = values[(yVals - r - 1)*xVals + c]; break; case 64: sample = values[r*xVals + c]; break; default: System.err.println("You must add support for scanmode: " + scanMode); break; } // If the values equals the missing data // indicator. Set to NaN if (sample == mdi) sample = Float.NaN; // Put the sample into the array flatSamples[0][ c * yVals + r ] = sample; // Record the range of data if ((sample > maxValue) && (sample < mdi)) { maxValue = sample; } if (sample < minValue) minValue = sample; } } return(flatSamples); } public static void main(String[] args) throws Exception { new GribTest(); } }