UV coordinates vs Point coordinates

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1

Hi all,

 

I am trying to figure out what is the difference between UV and XY. It seems that UV is on a totally different coordinate system? If so, how do you know what that is?

 

I have an example of where they are showing the same numbers, but they are definitely different things?

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4.png723×717 114 KB

Thank you.

2

UV coordinates are relative to the size of the face. This is as opposed to absolute coordinates e.g XYZ

So u=0.5 V=0.5 is in the middle of the face.

In the below rectangle 100x200 in size

U=0.104, so x is 100x0.104=10.4

V=0.143, so y=200x0.143=28.6

20160518 uv coordinates
20160518-uv-coordinates.png1585×844 93.3 KB

3

Here is a thorough description of the difference between UV and XY space
http://dynamoprimer.com/05_Geometry-for-Computational-Design/5-3_points.html