[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[IDV #WZL-307950]: GFS global issue

Hi Walt-

This is Don.

> It still occurs with your bundle. I took a print screen shot of my
> settings in IDV and the map window.
> Computer Specs:
> Intel Core 2 6300 @1.86Ghz
> 2.74GB Ram
> GFORCE FX5200
> JAVA 6
> Heap size 1573MB
> 
> Let me know if you need any more information.
> Walt

This is a known problem and the only solution/workaround is to display the data 
in it's native projection.  See:

http://www.unidata.ucar.edu/software/idv/docs/userguide/Bugs.html#dataprojection

The problem occurs when the IDV attempts to account for the projection seam.  
The contour lines are drawn in the native coordinates, but reprojected onto the 
display projection.  In that case, we need to "cut" lines appropriately and the 
logic for doing that is not handling things in all cases.  We'll look into this 
to see if we can make it better, but again, the only real "solution" for now is 
to display it in the native projection.  I understand that is not optimal.  
Also, for this issue, Fast Rendering would tend to make things worse I would 
think because it doesn't try to account for the projection seams.

Have a happy New Year.

Don Murray

> Unidata IDV Support wrote:
> > Hi Walt,
> >
> >
> >> I know you have put a fix for spurious lines; I downloaded it and tried
> >> to use that to fix  a problem I had been trying to figure out but it
> >> didn't work. Whenever I load the GFS global data (US centered data has
> >> no problems whatsoever)  I get lines running across the globe especially
> >> the CONUS views; I first thought that this was a fast rendering problem
> >> but turning fast rendering off doesn't do anything. I then noticed today
> >> that when I change the projection to the GFS grid projection the issue
> >> is resolved. It would be nice if this could be fixed so that we could
> >> use the GFS global views with custom projections.
> >>
> >>
> >
> > You can get weird map lines in some projections when fast rendering is 
> > turned on.
> > I don't have any problems in displaying maps in a GFS global projection. 
> > Try viewing the attached bundles and see if you are having problems or send 
> > us a bundle that demonstrates the problem.
> >
> > Maybe this is still an issue with the graphics card.
> >
> > -Jeff
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: WZL-307950
> > Department: Support IDV
> > Priority: Normal
> > Status: Closed
> 
> 


Ticket Details
===================
Ticket ID: WZL-307950
Department: Support IDV
Priority: Normal
Status: Open