Displaying 3D data in 2D

Hello, everyone

I have a problem which I have half-solved, but it appears to me that I am abusing the framework to get there, rather than working with it. Hints as to a better/more elegant way to do what I want would be greatly appreciated.

I have a 3D domain data set (altitude - lat - lon) of 1-D data (temperature). I need to make and display 2-D horizontal slices out of this data.

To date, I:

1) Convert my data from it's native format (ASCII vectors) to a VisAD data structure more or less as follows
        // declare the data types to be used
        RealTupleType domainType = new RealTupleType(altitude, latitude, 
        RealTupleType rangeType = new RealTupleType(domainType,temp);

// parse the input file to create appropriately ordered temperature and coordinate ranges
        float geoSamples[][] = getCoords);
        float tempSamples[][] = getTemps();

        // make the domain set
Gridded3DSet domain3DSet = new Gridded3DSet(domainType, geoSamples, numAlts, numLats, numLons);

        // create the flatfield, and populate it with the observations
        FlatField dataItem = new FlatField(rangeType, domain3DSet);

2) To get, say, the surface level temperatures, I need to get this data structure into a 2D field, because I can't make a 2D ScalarMap to a 3D field. So I make a new 2D domain set and 2D Flatfield of the k-th level by
        // create data structures to hold new samples   
        float newGeoSamples[][] = new float[2][numLats*numLons];
        float newTemperatures[][] = new float[1][numLats*numLons];

        // extract the lats and lons we need to make a 2D set
        for (i=0; i<numLon; i++) {
                for (j=0; j < numLon; j++) {
                        index3D = level + numLevel*j + numLevel*numLat*i;       
                        index2D = j + numLat*i;
                        newGeoSamples[0][index2D] = geoSamples[1][index3D];
                        newGeoSamples[1][index2D] = geoSamples[2][index3D];
        // create the appropriate 2D data type descriptors
        domainTuple2D = new RealTuple   Type(latitude, longitude);
        functionType2D = new FunctionType(domainTuple2D, temperature);

        // create the 2D flat field
Gridded2DSet domain2DSet = new Gridded2DSet(domainTuple2D, newGeoSamples, numLats, numLons);
        FlatField field2D = new FlatField(functionType2D, domain2DSet);

3) Now I can create ScalarMaps, DataReferences, and plot my data in the normal satisfactory manner.

So why do I think I'm missing something?  Well,

A) I'm creating two entirely duplicative arrays in step two, at a considerable memory loss.

B) I'm entirely avoiding using any of resample's built-in interpolation features, which seems highly counterintuitive.

C) GriddedSets can't handle missing data, if any. Which can happen in my problem domain.

I can't be the first person to want to do this, so I'm sure there's a more straightforward, efficient way. What am I missing? Correct use of Coordinate Systems? Correct use of IrregularSets? Can anyone point me to some example code I should have been looking at?


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