VTK.js + trame: No textures in local rendering => minimal example for python ?

Henryk · January 2, 2025, 7:40pm

Hey everyone,

I’m a new and unexperienced user of VTK + Trame for displaying mechnical parts in a browser and
I’m impressed what can be done with just a few lines of code.
So far, I got a working python-code to render my parts coming from a calculation-script,
what is my major topic.
I’m thinking of using Trame + VTK to present/share these results with other
team-members; it would be very handy for them just to open their brower to get a
first impression of these parts.
Local rendering would be pretty useful, because some team-members may be far away.

So far, I got everthing working what I wanted to achieve, except one thing:
textures in local-rendering mode.
I’m likely facing the same trouble that is already described here:

github.com/holoviz/panel

Add using Trame example to support all vtk features

opened 07:44AM - 03 May 23 UTC

tkoyama010

#### Is your feature request related to a problem? Please describe. Currently v…tk.js is used in panel projects (e.g. [VTK](https://panel.holoviz.org/reference/panes/VTK.html) and [VTKInteractive](https://panel.holoviz.org/gallery/demos/VTKInteractive.html)). vtk.js is currently not actively maintained, which leads to the problem that some vtk features are not supported (e.g. [Texture missing in pyvista plotter in Panel](https://discourse.holoviz.org/t/texture-missing-in-pyvista-plotter-in-panel/2750) and [Interaction with pyvista widgets](https://discourse.holoviz.org/t/interaction-with-pyvista-widgets/2328)). To remedy this, PyVista deprecated the use of vtk.js and made [trame](https://kitware.github.io/trame/docs/index.html) the standard. PyVista supports jupyter rendering with trame via the show method, which allows it to be rendered to the panel via ipywidget. <details> <summary>Code</summary> Using [Physically Based Rendering example](https://docs.pyvista.org/version/stable/examples/02-plot/pbr.html). ```python import panel as pn import pyvista as pv from IPython.display import IFrame from pyvista import examples def handler(viewer, src, **kwargs): return IFrame(src, "75%", "500px") # Load the statue mesh mesh = examples.download_nefertiti() mesh.rotate_x(-90.0, inplace=True) # rotate to orient with the skybox # Download skybox cubemap = examples.download_sky_box_cube_map() p = pv.Plotter(notebook=True) p.add_actor(cubemap.to_skybox()) p.set_environment_texture(cubemap) # For reflecting the environment off the mesh p.add_mesh(mesh, color="linen", pbr=True, metallic=0.8, roughness=0.1, diffuse=1) # Define a nice camera perspective cpos = [(-313.40, 66.09, 1000.61), (0.0, 0.0, 0.0), (0.018, 0.99, -0.06)] iframe = p.show( jupyter_backend="trame", jupyter_kwargs=dict(handler=handler), return_viewer=True, cpos=cpos, ) pn.extension() pn.panel(iframe, width=2000).show() ``` </details> [Screencast from 2023-05-03 16-09-10.webm](https://user-images.githubusercontent.com/7513610/235856497-3821624b-1435-4a57-84f7-6053c7f8643b.webm) #### Describe the solution you'd like Please document this example and encourage people to use trame. #### Describe alternatives you've considered None #### Additional context See the detail of discussion [here](https://discourse.holoviz.org/t/trame-support-in-panel-to-fully-support-vtk/5275).

Short description: The skybox and other textures work fine in remote-rendering-mode, but
vanish when switching to local-rendering mode.

I added the textures a little different, but I guess it is the same problem:
…
jpg_img_reader = vtk.vtkJPEGReader()
jpg_img_reader.SetFileName(‘Feldanker_1.jpg’)
#jpg_img_reader.SetFileName(“http://localhost:8800/html/Feldanker_1.jpg”) # Failed!

Box_texture = vtk.vtkTexture()
Box_texture.SetInputConnection(jpg_img_reader.GetOutputPort())
Box_texture.Modified()

Box_source = vtk.vtkCubeSource()
Box_Mapper = vtk.vtkPolyDataMapper()
Box_Mapper.SetInputConnection(Box_source.GetOutputPort())

Box_Actor = vtk.vtkActor()
Box_Actor.SetMapper(Box_Mapper)
Box_Actor.SetTexture(Box_texture)
Box_Actor.GetProperty().SetDiffuse(0.1)
Box_Actor.GetProperty().SetAmbient(1.0)
plotter.add_actor(Box_Actor)

Skybox = vtk.vtkSkybox()
Skybox.SetTexture(sky_map)
Skybox.SetFloorRight(0, 0, 1)
Skybox.SetProjection(vtk.vtkSkybox.Cube)
plotter.add_actor(Skybox)
....

A similar question to the vanishing textues was asked here a short time ago:

, but it is unclear to me how it was solved.
Going throught the skybox-C+±Examples mentioned there did not help me, some classes
are missing in the python-VTK-package, e.g. there seems to be no vtkHttpDataSetReader.

I understand, that vtk and vtk.js is not 100% the same, but is there a minimal example
for python similar to

github.com/holoviz/panel

Add using Trame example to support all vtk features

opened 07:44AM - 03 May 23 UTC

tkoyama010

#### Is your feature request related to a problem? Please describe. Currently v…tk.js is used in panel projects (e.g. [VTK](https://panel.holoviz.org/reference/panes/VTK.html) and [VTKInteractive](https://panel.holoviz.org/gallery/demos/VTKInteractive.html)). vtk.js is currently not actively maintained, which leads to the problem that some vtk features are not supported (e.g. [Texture missing in pyvista plotter in Panel](https://discourse.holoviz.org/t/texture-missing-in-pyvista-plotter-in-panel/2750) and [Interaction with pyvista widgets](https://discourse.holoviz.org/t/interaction-with-pyvista-widgets/2328)). To remedy this, PyVista deprecated the use of vtk.js and made [trame](https://kitware.github.io/trame/docs/index.html) the standard. PyVista supports jupyter rendering with trame via the show method, which allows it to be rendered to the panel via ipywidget. <details> <summary>Code</summary> Using [Physically Based Rendering example](https://docs.pyvista.org/version/stable/examples/02-plot/pbr.html). ```python import panel as pn import pyvista as pv from IPython.display import IFrame from pyvista import examples def handler(viewer, src, **kwargs): return IFrame(src, "75%", "500px") # Load the statue mesh mesh = examples.download_nefertiti() mesh.rotate_x(-90.0, inplace=True) # rotate to orient with the skybox # Download skybox cubemap = examples.download_sky_box_cube_map() p = pv.Plotter(notebook=True) p.add_actor(cubemap.to_skybox()) p.set_environment_texture(cubemap) # For reflecting the environment off the mesh p.add_mesh(mesh, color="linen", pbr=True, metallic=0.8, roughness=0.1, diffuse=1) # Define a nice camera perspective cpos = [(-313.40, 66.09, 1000.61), (0.0, 0.0, 0.0), (0.018, 0.99, -0.06)] iframe = p.show( jupyter_backend="trame", jupyter_kwargs=dict(handler=handler), return_viewer=True, cpos=cpos, ) pn.extension() pn.panel(iframe, width=2000).show() ``` </details> [Screencast from 2023-05-03 16-09-10.webm](https://user-images.githubusercontent.com/7513610/235856497-3821624b-1435-4a57-84f7-6053c7f8643b.webm) #### Describe the solution you'd like Please document this example and encourage people to use trame. #### Describe alternatives you've considered None #### Additional context See the detail of discussion [here](https://discourse.holoviz.org/t/trame-support-in-panel-to-fully-support-vtk/5275).

to solve the issue with missing textures in the skybox and/or planes in local rendering mode?

Sebastien_Jourdain · January 6, 2025, 4:43am

Welcome to the community!

Since you are using VTK, you might be ok by using trame-vtklocal with just 2 lines change.

Basically replace trame.widgets.vtk.VtkLocalView by trame.widgets.vtklocal.LocalView.

You will need vtk 9.4+ and trame-vtklocal

pip install "vtk>=9.4.1" trame-vtklocal

You can find a usage example here.

Henryk · January 6, 2025, 11:42am

Hey Sebastien,

thank you very much, your example helped me to get the textures to work!
I successfully got cubemaps and HDR to work for the skybox.

Just one more thing: I guess, the addtional window should be synchronized with the browser-window(?) This doesn’t work for me, the second window always freezes, also with the original example-code.

Sebastien_Jourdain · January 6, 2025, 5:11pm

You should set your render window to be offscreen, that will prevent that window to even pop-up.

Henryk · January 8, 2025, 12:32pm

Dear VTK-team,
dear Sebastien,

from older discussion on stack-overflow I got the impression, that local-rendering comes with some limitation, is this any longer true? I’m really happy, that also PBR is availible in local-rendering-mode.

I just want to to say thank you for your help and this great piece of software!

Sebastien_Jourdain · January 9, 2025, 5:54pm

Any limitation for local rendering when using VTK/WASM should totally disappear by end of 2025 (). And as you’ve notice we are already pretty far along, but we can still expect some hiccup here and there.

Since VTK is working on moving to WebGPU, it will address a lot of the rendering limitation we currently have in the browser too. Also we are working to add more testing especially targeting our serialization infrastructure for our WASM usage. When those complete, we should reach full parity. And like I said, a lot of that is expected to happen in 2025.