GIMP Version: 2.10.14
Operating System: Windows
OS Version: Windows 10
GIMP Experience: Basic Level

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Hi everyone,

I am reproducing an old manual. I was successful in making a rectangle with rounded corners with a line thickness in millimeters. I can't find how to do this with a straight line ?? I can choose the thickness using different tools like a pencil or the paintbrush but the thickness is in px and I can't find a way to change the units.

Is this possible ?

Thank you in advance for your help!

Hello Oby4455,

I have searched a way to set line thickness in millimeter... and i don't find... sorry.

You can find how much pixels used for one millimeter in the image resolution you are working on.
For exemple in :
- Menu Image -> Image scale and size
- Choose Resolution X ... 3,9370 ... in pixels/mm

You can round to 4 pixels/mm if you want.

Good design.
@+++

Thank you anyway. I find a work around. I drawed the rectangle on a separate layer and then cut the parts I do not need to make a straight line. It works well for what I need to do but I wish I knew a better way.

To put it mildly, Gimp is not the best tool for any sort of technical drawing. Inkscape is a bit better.

Example: 2mm line width. Draw your straight line using the path tool, stroke the path.