Can you provide some code that demonstrates the problem you are seeing? Also, what version of IDL are you using?

Hi I am using Version 8.2.0.20120410. Here comes the code: X = [1,3,5,6,4,1,1] Y = [2,1,4,6,7,5,2] plot = PLOT(X,Y,/NODATA) Poly = POLYGON(X,Y, FILL_COLOR='Tan',/Data) poly.Save, 'polygon.eps' Looking at the eps, one can see the triangles with the common point [1,2]. As I understand the code from "\lib\itools\ipolygon.pro" at line 137 right: oPolygon->SetProperty, _DATA=points, /TESSELLATE, _EXTRA=_extra there's some implicit tesselation going on. But i cant prevent IDL from doing it ... Cheers

I think it is possible that what you are seeing are artifacts from your PostScript viewer, and have nothing to do with the PostScript file itself: http://www.idlcoyote.com/ps_tips/psstripes.html I believe if you printed the file, these lines wouldn't show up. I know if I convert the file to, say, a PNG file, they don't show up: IDL> cgPS2Raster, 'polygon.eps', /PNG

Hi David, ur right. Switching off the anti-aliasing of gsview helps. But i want to use eps-files in a high quality latex dokument, where i dont want to turn off anti-aliasing nor using raster images. My question remains: Why the tessellation of the polygons? Writing polygons with other programs to eps-file do not produce the triangle effects. Btw: Writing to a pdf (vector format) do not produce this effect. Regards

You might want to get in touch with ExelisVIS technical support to see what they have to say. Let them know your operating system, version of IDL the sample code you used and your license number.