Translate/transform bug for long distances

[javi-mr]

Hello!

When I try to translate a triangulated surface (PolyData) to a far position ([438384.09, 4478309.04, 661.21]) the final mesh is completely deformed. Do you know why?

Is there any method to translate the surface by setting the new center of the mesh?

Thank you!

[banesullivan]

Oh wow. This is indeed odd

import pyvista as pv

mesh = pv.Sphere()
trans = mesh.translate([438384.09, 4478309.04, 661.21])
trans.plot()

And we get the same thing with:

import pyvista as pv

mesh = pv.Sphere()
mesh.points += [438384.09, 4478309.04, 661.21]
mesh.plot()

This is unexpected...

[luizenger]

Instead of redefining the center point of the existing object, couldn't you just delete the previous object and create a new one at the specified location?
The translate( ) method does this anyway if I understood the code correctly (the newly generated mesh substitutes the existing one if inplace=True)

[banesullivan]

You may be able to apply a transform to the actor without modifying the points of the mesh: https://docs.pyvista.org/api/plotting/_autosummary/pyvista.Actor.user_matrix.html#user-matrix

[JasperBoogers]

Is it possible to convert all data arrays to double precision, so to extend the result points_to_double() to all arrays? for example, all cell normal vectors and areas? I found very little documentation on this topic online, including the existence of points_to_double()

[banesullivan]

This is not currently implemented but I agree it should be. Would you be open to contributing this feature?

[JasperBoogers]

I would be honoured, but not for another month at least. I first have to finish a master's degree (which I could not have done without Pyvista 😄 )