PrintDisplay doesn't do what I want

I’m in Rhino 4.

I’d like PrintDisplay to show lines at the thicknesses assigned to them. Shown, of course, as big on the screen as corresponding to how much I have zoomed in. (Just like every other object is shown correctly.)

Instead, there’s a parameter. I can adjust this parameter to make it look right.

(Here’s how: Put a 0.3mm line inside a parallel long box with 0 thickness sides. Turn on PrintDisplay. Adjust the parameter to make line just fill the box. But I have to readjust this parameter every time I zoom differently.)

Am I missing something? Is there some other way to do what I want?


Not really, that’s the way it works.

Not really, no. You would have to make planes with the correct width instead of lines and calibrate your viewport to your screen to be able to zoom 1:1.

Yeah, I figured … it was pretty clear what it does. BUT I can’t for the life of me figure out why Rhino does it this way. Either I want to see a line as just a line, or I want to see it at its print width. “See it at its print width” means that a line with width 0.4mm looks, on the screen, as wide as, for instance, a rectangle (with line width zero) that is 0.4mm wide. If I zoom in or out, this remains true. Nothing to adjust.

I suggest (so that you don’t change PrintDisplay) you have a command ShowLineWidths that does this.

The tool was developed back when “high resolution” meant 1024 x 768 on a 19" CRT monitor.
It’s only recently with the 4K monitors that screen resolution even made something approaching actual line width is even possible.

The issue is that the line width is defined as the width on the printed output which means that a viewport needs to know what the output rectangle is supposed to be. Layouts know what their output rectangle is supposed to be which is why print width behaves different on layouts than in general modeling viewports.