LaTeX in PyVista Plots

[dominik-kern]

Is there any chance to use a TeX interpreter on labels such as scalar_bar?
This would enable a uniform appearance and improve the integration into documents, right now I reduce all labels to the bare minimum and write about them in the text, anyway for greek symbols, small expression this would be very useful.
In the documentation I found only how to change the font.

[guido-granda]

Hello, I also have the same problem. But, I know that Latex used to work in previous version of pyvista. Look at this picture

[banesullivan]

This requires VTK to be built with mathtext support. Are you installing from PyPI or from conda-forge? I think the wheels on PyPI are built with this by default (but I'm not 100% sure)

I don't think this is enabled for the conda-forge VTK build, see conda-forge/vtk-feedstock#79

A quick way to tell if this is supported in your build of VTK is the following:

>>> import vtk
>>> vtk_mathtext = vtk.vtkMathTextFreeTypeTextRenderer()
>>> vtk_mathtext.MathTextIsSupported()
True

[banesullivan]

For this specifically, your version of PyVista will not matter too much.

For Matplotlib 3.6.2, only VTK 9.2.5 is compatible.

For VTK<9.2.5, you must use Matplotlib<3.6

---

How are you installing VTK? With pip or conda or a custom build?

Can you share a pv.Report()?

Can you try re-installing both matplotlib and VTK when you have compatible versions?

I recently added good image regression tests for this in #3781 and further clarified the compatible versions in #3838. I feel pretty confident that you just need to have clean installations of compatible VTK and Matplotlib versions

[kaathaarinaa]

ok, so I install vtk using pip.
Therefore, after uninstalling matplotlib and vtk, as you suggested, I do:

pip install matplotlib==3.6.2
pip install vtk==9.2.5

the result of the two tests after reinstall is:

# Test 1
>>> import vtk
>>> vtk_mathtext = vtk.vtkMathTextFreeTypeTextRenderer()
>>> vtk_mathtext.MathTextIsSupported()
True
# So that should be fine

# Test 2
import pyvista as pv
p = pv.Plotter()
p.add_text(r'$\rho$')
p.show()
# not working and still displaying $\rho$

pv.Report():

  Date: Tue Jan 31 15:42:45 2023 Mitteleuropäische Zeit

                OS : Windows
            CPU(s) : 48
           Machine : AMD64
      Architecture : 64bit
               RAM : 63.9 GiB
       Environment : Python
        GPU Vendor : ATI Technologies Inc.
      GPU Renderer : AMD RADEON HD 6450
       GPU Version : 4.5.13417 Core Profile Context 0

  Python 3.8.2 (tags/v3.8.2:7b3ab59, Feb 25 2020, 23:03:10) [MSC v.1916 64 bit
  (AMD64)]

           pyvista : 0.38.dev0
               vtk : 9.2.5
             numpy : 1.22.4
           imageio : 2.22.4
            scooby : 0.7.1
             pooch : v1.6.0
        matplotlib : 3.6.2
           IPython : 8.7.0
             scipy : 1.9.3
              tqdm : 4.64.1

[banesullivan]

Oh hm. Windows is always a wildcard. I'll see if I can break out my windows machine and see if I can get it working there.

This line worries me that it may not be enabled:

https://gitlab.kitware.com/vtk/vtk/-/blob/master/.gitlab/ci/configure_windows.cmake#L20

[kaathaarinaa]

Thanks for the reply. I am not sure I fully understand the relevance, but I could go for an editable install of vtk and just change that line if that helps?

[banesullivan]

I recently confirmed on a windows machine that math text symbols are not working... This seems like an upstream VTK issue to me.

[Joalland]

Hi there. This may be strange but when I do :

import pyvista as pv
p = pv.Plotter()
p.add_text(r'$\rho$')
p.show()
# not working and still displaying $\rho$

it doesn't produce the latex.

But then i open another shell and I do :

import vtk
import pyvista as pv
p = pv.Plotter()
p.add_text(r'$\rho$')
p.show()
#it works !

it works. (However it doesn't work if I don't open another shell).

My pv.Report() is :

--------------------------------------------------------------------------------
  Date: Tue Mar 07 18:58:29 2023 +04

                OS : Linux
            CPU(s) : 8
           Machine : x86_64
      Architecture : 64bit
               RAM : 31.2 GiB
       Environment : IPython
       File system : ext4
        GPU Vendor : Intel
      GPU Renderer : Mesa Intel(R) UHD Graphics (CML GT2)
       GPU Version : 4.6 (Core Profile) Mesa 21.2.6

  Python 3.8.10 (default, Nov 14 2022, 12:59:47)  [GCC 9.4.0]

           pyvista : 0.37.0
               vtk : 9.2.2
             numpy : 1.22.3
           imageio : 2.21.2
            scooby : 0.7.1
             pooch : v1.6.0
        matplotlib : 3.5.3
             PyQt5 : 5.14.1
           IPython : 7.13.0
          colorcet : 3.0.1
             scipy : 1.7.3
              tqdm : 4.64.1
            meshio : 5.3.4
        jupyterlab : 3.6.1
--------------------------------------------------------------------------------

[FrankFrank9]

@banesullivan Yes, 100% sure, I do agree with you that it is very odd but I do not have an explanation for that...

[Steriva]

I have faced a similar issue recently. I don't know if this problem has already been solved, nevertheless I will post it for completeness.

At first, I performed the following test

import vtk
vtk_mathtext = vtk.vtkMathTextFreeTypeTextRenderer()
vtk_mathtext.MathTextIsSupported()

getting True as expected. Then, if I try to use add a Latex expression in PyVista with

import pyvista as pv
plotter = pv.Plotter()
plotter.add_text(r'$\rho$')
plotter.show()

The code outputs $\rho$, so I have done the following

import vtk
import pyvista as pv
plotter = pv.Plotter()
plotter.add_text(r'$\rho$')
plotter.show()

and the rho is displayed correctly.

Best,
SR

[guido-granda]

@Steriva can you do a pv.Report() and post the result here please

[Steriva]

Yes, of course.
Without the vtk import

import pyvista as pv
pv.Report()

i get the following

OS	Linux	CPU(s)	16	Machine	x86_64
Architecture	64bit	RAM	31.1 GiB	Environment	Jupyter
File system	ext4	GPU Details	error	MathText Support	False
Python 3.10.12 | packaged by conda-forge | (main, Jun 23 2023, 22:40:32) [GCC 12.3.0]
pyvista	0.42.2	vtk	9.2.6	numpy	1.23.5
matplotlib	3.8.0	scooby	0.7.2	pooch	v1.7.0
pillow	10.0.0	PyQt5	5.15.9	IPython	8.15.0
ipywidgets	7.7.2	scipy	1.11.2	tqdm	4.66.1
meshio	5.3.4	jupyterlab	4.0.6	nest_asyncio	1.5.8

on the other hand importing vtk

import vtk
import pyvista as pv
pv.Report()

the output is

OS	Linux	CPU(s)	16	Machine	x86_64
Architecture	64bit	RAM	31.1 GiB	Environment	Jupyter
File system	ext4	GPU Details	error	MathText Support	True
Python 3.10.12 | packaged by conda-forge | (main, Jun 23 2023, 22:40:32) [GCC 12.3.0]
pyvista	0.42.2	vtk	9.2.6	numpy	1.23.5
matplotlib	3.8.0	scooby	0.7.2	pooch	v1.7.0
pillow	10.0.0	PyQt5	5.15.9	IPython	8.15.0
ipywidgets	7.7.2	scipy	1.11.2	tqdm	4.66.1
meshio	5.3.4	jupyterlab	4.0.6	nest_asyncio	1.5.8

[banesullivan]

We should start a thread on the VTK discourse about this as it seems VTK and vtk.vtkMathTextFreeTypeTextRenderer().MathTextIsSupported() has inconsistent behavior

https://discourse.vtk.org/