# How do I measure the distance between two UV vertices?

I am using Blender version 2.77a. I am attempting to make a paper model of a mesh that has been UV mapped, but not to scale. I need to:

• Measure the distance between any two vertices on a UV map

• Make a duplicate of a UV island

• I'm not sure I understand what you're trying to do. Can't you blow up the the UV layout and print it at whatever size you need?
– Matt
Jun 24, 2016 at 21:15
• ....or are you wanting to make the papercraft version without having to print out the UV layout?
– Matt
Jun 24, 2016 at 21:17
• What do you mean by "make a duplicate of a UV island", wouldn't Shift+D be sufficient, or I am I not understanding what a UV island is? Jun 24, 2016 at 22:00
• Duplicate an UV island makes no sense. "Geometry" in the UV mapping is dependant on the actual geometry. You can't add anything only in the UV geometry. Jun 24, 2016 at 22:17
• By duplicate a UV island I was wondering if it was possible to copy a UV island without copying geometry(some parts of the model were mapped to the same UV coordinates) Jun 25, 2016 at 17:07

I don't believe there is any true way to measure the distance between two vertices in the uv image editor, but there is a fairly simple workaround.

# Finding the (x,y) distance between two points

With your mesh unwrapped and the UV/image editor open, open the properties panel within the editor via n. At the top there will be what is called "UV vertex". Once you select a vertex it will tell you the coordinates of the vertex.

Okay, now the hard part. After finding the coordinates of the second vertex use the distance formula, which is: √ (x2−x1)2+(y2−y1)2
This online distance caculator should make things easier.

# Duplicating a UV island

In 3D View

First and foremost you must select the desired UV island, like so:
1. Enter edit mode TAB
2. Put select mode on "face" CTRL+TAB
3. Hover mouse over the desired UV island and press L.
4. Hit Shift+D

In UV/Image Editor

Whatever you copy and paste in 3-D view should appear in the image editor.

# References

How to select a UV island?

• I'm not sure if calculating the distance in pixels is the right way here, at least calculate it with normalized coordinates so the range will be 0 to 1.00 ; by default an unwrapped mesh with no image loaded will be mapped on an empty canvas size of 256x256 pixels , once you load an image your calculated distance is off , especially if the image is not square dimension. not to mention the rounding errors between integers and decimals. i may be wrong about this though.
– user2816
Jun 24, 2016 at 23:11