The undersampling happens because VisAD uses texture mapping
by default for effciency. You can disable it by:
GraphicsModeControl mode = display.getGraphicsModeControl();
You can also limit the degree of undersampling with texture
p.s., visad-list-digest is not working, but our system
admins are working on fixing it.
Bill Hibbard, SSEC, 1225 W. Dayton St., Madison, WI 53706
hibbard@xxxxxxxxxxxxxxxxx 608-263-4427 fax: 608-263-6738
On Mon, 20 May 2002, Tom Nelson wrote:
> I have just started using VisAD. I want to visualize
> a 'terrain' of data samples, say 100x100 in longitude
> and latitude, with various height values.
> I modified P4_01.java from the tutorial to do this.
> I also added option buttons to allow me to set PolygonAttributes
> to POLYGON_FILL, POLYGON_LINE, and POLYGON_POINT, and to
> also setPointMode(true) or (false) on the GraphicsModeControl.
> When I setPointMode(true), I see all of my data samples.
> When I attempt to show a 'terrain' (POLYGON_FILL) or a grid
> (POLYGON_LINE) there is an undersampling of my data points
> leading to an incorrect display.
> I see the same effect with the original P4_01.java code
> when I add my components to change the PolygonAttributes
> and/or the PointMode. The 50x50 samples are reduced to 25x25
> in the POLYGON_LINE and POLYGON_POINT mode.
> I've been digging into the source code to track down just where
> my samples are converted to Java3D objects, and I've also
> looked in this list archive for previous question about this.
> Ideally, I'd like to have control over whether my data is undersampled
> or not. I just haven't stumbled on the obvious way to fix that!
> Tom Nelson