# Histogram line width in Postcript file

Hi,

I want to set the line width of an histogram in a eps file, and add
things after with TeX and the XY-Pic extension to obtain the best
result. But the method SetLineWidth use pixel units. If I understand
well, it’s due to the fact that the line width doesn’t change with
zoom operation. But the paint routine use the same interface for X
display and Postscript output. So, if you change after the ratio of
the eps, the vertical lines haven’t the same size that horizontal
lines, since the conversion factor are different for x and
y. Moreover, I can’t recompute exactly these conversion factors from
the dimensions. It’s a normal feature or a bug/improvement? It seems
break the vectorial concept of Postscript. I suggest to use two line
width, one for X display in pixel units and one for Postscript in mm.
And compute automaticly the other with a arbitrary conversion if it is
not specified.

Hi Fabrice,

the default line scale for postscript output is 3. This can be changed either by TPostScript::SetLineScale() or TStyle::SetLineScalePS().

Cheers,
Oliver

Sorry, but your response is out of subject.

I attach a ps to show the problem.
c0.ps (17.9 KB)

The line width scale factor along X and Y axis is the same in PS files. I am not able, right now, to visualise your eps file (the PC i am reading my email from has no PS viewer, I am on holidays), but I do not understand your problem. The line width in PS file is define thanks to a single PS command and it doesn’t matter later on wether the lines are vertical, horizontal or diagonal.