VTK.wasm 'ghost pixel' in browser

Web vtk.wasm
1

Hi,

I started with VTK.wasm. My first goal was, display an empty blue screen. But the display contains white pixel from the bottom left to the top right corner.

In a second step, I added a cone. The diagonal white pixel disappeared. Then I removed the cone from the renderer. The diagonal pixel appeared again together with some pixel of the cone.

Any idea what happens here? Thank you for any help.

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2

Hi @HST

I’ve never seen anything like that before. What browser?

3

Hi Jaswant,

Google Chrome, Version 149.0.7827.201 (Offizieller Build) (64-Bit)

Microsoft Edge, Version 150.0.4078.48 (Offizielles Build) (64-Bit)

4

Hi again, I tried the cone example from the VTK web page and removed the cone to display an empty window. I also got the white diagonal ‘ghost pixel’ in the browser.

I can start my application also in native mode, using my own VTK build. This works fine, without any ‘ghost pixel’.

May there something be wrong with my VTK.wasm build?

5

The described behaviour seems to be related to NVIDIA graphics cards. I use NVIDIA Quadro P5000. On other machines with an Intel graphics adapter, the issue doesn’t appear.

A quick fix is as follows: deactivate “Use hardware acceleration when available” in the Chrome browser settings. Settings → System → Use hardware acceleration when available