UV image size question

Support Materials and Textures
1

According to this book I got on Game Modeling, it says that 1 cm is equal to 1 pixel, therefore if your object was 1 meter you would need a 100 pixel image to get the proper resolution.

To test it I have a cube with edge lengths of 2.0, i am assuming this would equate to 2 meters and a resolution of 200 pixels. However when I unwrap the UV’s and save the face layout at 512 or 1024, in Photoshop the squares are not 200x200, but something else.

Am I translating the edge length correctly in Blender or do I need to do something else. How do I set the scale correctly to equate 1cm to be 1pixel?

2

However when I unwrap the UV’s and save the face layout at 512 or 1024, in Photoshop the squares are not 200x200, but something else.
The uv layout image which you export from Blender shows the layout, where the vertices and faces are, size of that image does not have to do with the resolution of final image or in this case the game´s texture resolutions.
But for the purpose of texture making you can scale the uv face layout image to a size in which the squares are 200 X 200 pixels approximately.
In

3

Am I translating the edge length correctly in Blender or do I need to do something else. How do I set the scale correctly to equate 1cm to be 1pixel?

You are going about it correctly.