Units in VTK

What units of measurement does vtk use? I have scans from a CMM with an accuracy of 5 micrometers. I would like to display them by adding the primitives I created to them. Here the question arises what units does vtk accept? The stl file does not contain such information, so as I understand it I have to make sure that these units are specified at the outset?

There is no units in VTK, only numbers.

If your numbers are in micrometers, then your unit is micrometers.

Ok thanks, so i should define units at start

Hi, Mathieu, Iā€™m wondering how that number maps to the pixels. For example, when I set space of the grid as 1, what does this 1 represent, how does vtk know how many pixel it should use for this space, thanks! Is it just a relative value?

That depends on the camera parameters and the projection to the screenspace.

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