Gimp exact sizes

[icosahedron]

Thanks for the ideas guys.

[jfrazierjr]

As others have alluded to, the selection tools will work in a pinch and can be made to work fairly well as long as you have simple requirements. As long as you don't have any diagonals, the selection tool will allow your to set your selection to a specific size and at a specific point, so you can get very precise with it as long as you only need to do stuff on the horizontal or vertical axis. It's when you need other angles that you get tripped up and GIMP is no longer easily able to deal...

I use this method quite frequently when making scale bars so I can get them precisely where I want them and have them be the correct size, even with multiple segments.