# Query with respect to WebGPU Rendering Backend in VTK WASM
**URL:** https://discourse.vtk.org/t/query-with-respect-to-webgpu-rendering-backend-in-vtk-wasm/16355
**Category:** vtk.wasm
**Tags:** vtkwasm
**Created:** [March 25, 2026, 8:24am UTC](https://discourse.vtk.org/t/query-with-respect-to-webgpu-rendering-backend-in-vtk-wasm/16355 "2026-03-25T08:24:11Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@RaMmer](https://discourse.vtk.org/u/RaMmer)
#### Post date: [March 25, 2026, 8:24am UTC](https://discourse.vtk.org/t/query-with-respect-to-webgpu-rendering-backend-in-vtk-wasm/16355/1 "2026-03-25T08:24:11Z")
Hello,
I have been working with VTK WASM over the past few weeks and have been experimenting with the webgpu rendering backend.
It works great for my use case which basically most of the time is around is just for visualizing complex polydata geometries. I understand that webgpu is still under experimental stage but I have query regarding some features which I need a bit more clarification.
**Gradient Renderer Background**
In, webgpu backend I have observed it is currently not possible to setup a gradient rendering background. In native VTK and webgl it works by setting it up with the renderer using the `SetBackground` and `SetBackground2` functions but these do not work with webgpu as rendering backend. It always shows the first background colour directly. Is it a feature limitation? Will the support for this be added in future for the WebGPU backend?
I have tried a workaround of setting the Background Alpha as 0 and making the background transparent and I thought once I have the transparent background I could make my own background using CSS but in this case The Background is always rendered opaque.
Is there any other workaround currently?
**Camera Orientation Widget**
The interactions for the Camera Orientation Widget does not work with the WebGPU rendering backend in VTK WASM, However, the work fine when my rendering backend is WebGL. How to support interactions of COW with webgpu backend in vtk-wasm?
Thank you,
Rammer
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### Author:  [@jaswantp](https://discourse.vtk.org/u/jaswantp)
#### Post date: [March 25, 2026, 1:40pm UTC](https://discourse.vtk.org/t/query-with-respect-to-webgpu-rendering-backend-in-vtk-wasm/16355/2 "2026-03-25T13:40:06Z")
Hi @RaMmer,
I can look into supporting gradient backgrounds in the `vtkWebGPURenderer`.
As for the camera orientation widget, it sounds like a picking problem. I’ll investigate.
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### Author:  [@RaMmer](https://discourse.vtk.org/u/RaMmer)
#### Post date: [March 26, 2026, 10:31am UTC](https://discourse.vtk.org/t/query-with-respect-to-webgpu-rendering-backend-in-vtk-wasm/16355/3 "2026-03-26T10:31:43Z")
Thank you for the updates, Jaswant!