Some tips regarding the unit in vtk.
I am curious how the boundry is mapped into the vtk and what does these units represent.
For example, when I try to set spacing of the structure grid as 1, what does that 1 represent?
Here is one related question online, but i’m still not quite sure about it:
https://discourse.vtk.org/t/units-in-vtk/12892
In practice, two same size figure on the screen can have different spacing (if we zoom it in and out properly)
It seems that this unit is related to camera settings and viewpoint.
So I try to look at how things work in opengl, how does opengl decide the unit since vtk rendering is mainly depedent on opengl currently.
