3D Clouds

• To: "visad-list@xxxxxxxxxxxxx" <visad-list@xxxxxxxxxxxxx>
• Subject: 3D Clouds
• From: Doug Lindholm <lind@xxxxxxxx>
• Date: Tue, 23 Mar 1999 12:17:09 -0700

Hello again,

I'd hate for traffic on this list to lag, so I'll pose a question. :-)

I have a 3D field related to cloudiness (e.g. 0=clear, 1=cloudy). I'd
like to map this to Display.Alpha to get a cool foggy effect. I managed
to do it for a single layer of clouds (with an Integer2DSet, nothing
mapped to ZAxis) but I am not having much luck getting a 3D
representation. The following gives me my 27 data values as *points*
with brightness proportional to cloudiness. (Mapping to Alpha gives me
nothing.) How can I make my scene cloudy?

Thanks,
Doug

    RealType lat = new RealType("lat",null,null);
    RealType lon = new RealType("lon",null,null);
    RealType alt = new RealType("alt",null,null);
    RealType[] coords = {lat,lon,alt};
    RealTupleType domain = new RealTupleType(coords);
    RealType cloud_type = new RealType("cloudy",null,null);
    FunctionType cloud_ftype = new FunctionType(domain,cloud_type);
    Set grid_set = new Integer3DSet(3,3,3);
    FlatField cloud = new FlatField(cloud_ftype,grid_set);
    float[][] data = {{0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,0.0f,
                       0.5f,0.3f,0.2f,0.3f,0.2f,0.1f,0.2f,0.1f,0.0f,
                      
1.0f,0.75f,0.5f,0.75f,0.5f,0.25f,0.5f,0.25f,0.0f}};
    cloud.setSamples(data);

    ScalarMap sm_lat = new ScalarMap(lat, Display.XAxis);
    display.addMap(sm_lat);
    ScalarMap sm_lon = new ScalarMap(lon, Display.YAxis);
    display.addMap(sm_lon);
    ScalarMap sm_alt = new ScalarMap(alt, Display.ZAxis);
    display.addMap(sm_alt);
    display.addMap(new ScalarMap(cloud_type, Display.RGB));
    //display.addMap(new ScalarMap(cloud_type, Display.Alpha));

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| Doug Lindholm, Software Engineer          |  E-mail: lind@xxxxxxxx   |
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