Re: ScalarMapListener

• To: Tom Rink <rink@xxxxxxxxxxxxx>
• Subject: Re: ScalarMapListener
• From: Donna L Gresh <gresh@xxxxxxxxxx>
• Date: Fri, 21 Feb 2003 14:01:37 -0500

OK, I can do that; but I wonder, why does the mapChanged method keep
getting called? It's not supposed to be "listening" to the destination
scalar map, is it?

Donna L. Gresh, Ph.D.
Optimization and Mathematical Software Group
IBM T.J. Watson Research Center
(914) 945-2472
http://www.research.ibm.com/people/g/donnagresh
gresh@xxxxxxxxxx




                                                                                
                                                     
                      Tom Rink                                                  
                                                     
                      <rink@xxxxxxxxx.e        To:       Donna L 
Gresh/Watson/IBM@IBMUS                                              
                      du>                      cc:       
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                      Sent by:                 Subject:  Re: ScalarMapListener  
                                                     
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                      02/21/2003 01:56                                          
                                                     
                      PM                                                        
                                                     
                                                                                
                                                     




If the setRange only needs to be done once, you could define and
check a boolean to see if it's been done.  Otherwise, you'll need
to see if the 'foo' values are changing, if not skip the setRange().

TomR


Donna L Gresh wrote:

> I'm back with another question;
> My fundamental need is to combine a "marker" (which might be a line) in a
> three-dimensional view. My basic data object is a surface which is mapped
> like xy->data, where x->Display.XAxis, y->Display.YAxis, and
> data->Display.ZAxis. So I have created a "line object" (which is just two
> points: {x, y, zmin} and {x, y, zmax} which marks a particular xy
location
> with a vertical line. So I have another math type which is {x2,y2,z2} and
I
> set up scalar maps for x2->Display.XAxis, y2->Display.YAxis, and
> z2->Display.ZAxis. I found however that I need to explicitly set the
range
> for the scalar maps for my marker line to match the range of the surface.
> The only problem is one that's been mentioned in the archive, that it
takes
> some amount of time for the autoscaling to occur. I inserted a short
wait,
> and that resulted in the right picture, so then I went ahead and created
a
> new class that implements ScalarMapListener as suggested in the archives.
> The constructor for the class gets two scalarmaps: the "source" scalar
map
> and the "destination" scalar map, so that in the mapChanged method I can
do
> something like
>
> foo = source.getRange();
> destination.setRange(foo[0], foo[1])
>
> The only problem is, the mapChanged method seems to be causing itself to
be
> called again in an infinite loop. Although I only do
> source.addScalarMapListener(myclass); I don't put a listener on the
> destination map.
>
> Am I doing something backwards? Is there a simpler way to do what I want?
>
> Thanks for any help
> Donna
>
> Donna L. Gresh, Ph.D.
> Optimization and Mathematical Software Group
> IBM T.J. Watson Research Center
> (914) 945-2472
> http://www.research.ibm.com/people/g/donnagresh
> gresh@xxxxxxxxxx

• References:
  • Re: ScalarMapListener
    • From: Tom Rink