# QQuickVTKRenderItem not working on emscripten

**URL:** https://discourse.vtk.org/t/qquickvtkrenderitem-not-working-on-emscripten/8027
**Category:** Development
**Created:** [March 10, 2022, 5:59pm UTC](https://discourse.vtk.org/t/qquickvtkrenderitem-not-working-on-emscripten/8027 "2022-03-10T17:59:22Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![Zoheir](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/z/a3d4f5/32.png) [@Zoheir](https://discourse.vtk.org/u/Zoheir)
#### Post date: [March 10, 2022, 5:59pm UTC](https://discourse.vtk.org/t/qquickvtkrenderitem-not-working-on-emscripten/8027/1 "2022-03-10T17:59:22Z")

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Dear,

I am trying to use the QQuickVTKRenderItem to render a vtk scene in a qml for web application using emscripten.

For my purpose i just changed the test in (GUISupport\QtQuick\Testing\Cxx) to be able to build and run for emscripten based on exemple in (Examples\Emscripten\Cxx\Cone)

All things are ok at build and compilation stage.

When i run my exemple on the browser (i tryed Chrome, mozilla and edge) i have the following WebGL warnning, in addition the rendering is not done (i have a white page)

“WebGL warning: blitFramebuffer: DRAW\_FRAMEBUFFER may not have multiple samples”

Any ideas to fix this Webgl warning ?

Note : i am using VTk 9.1 and Qt 5.15.2.

Thank you in advance.

Zoheir

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### Author: ![ben.boeckel](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.vtk.org/u/ben.boeckel)
#### Post date: [March 22, 2022, 5:25am UTC](https://discourse.vtk.org/t/qquickvtkrenderitem-not-working-on-emscripten/8027/2 "2022-03-22T05:25:05Z")

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@sankhesh

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### Author: ![sankhesh](https://discourse.vtk.org/user_avatar/discourse.vtk.org/sankhesh/32/73_2.png) [@sankhesh](https://discourse.vtk.org/u/sankhesh)
#### Post date: [March 22, 2022, 12:54pm UTC](https://discourse.vtk.org/t/qquickvtkrenderitem-not-working-on-emscripten/8027/3 "2022-03-22T12:54:13Z")

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@Zoheir, First, verify that you can do any WebGL rendering with QML + emscriptem (without VTK). I haven’t seen anyone doing that and am not sure if it is supported.

Regarding the warning, `QQuickVTKRenderWindow` disables multisampling on the `vtkRenderWindow` but you might have to set up a `QSurfaceFormat` to disable it on the QtQuick items as well.