[Graphic issue] Background pictures flickering

User story : As a user, I want the 3D rendering of the scene to be consistent and homogeneous, in order to be able to take screenshots for reports.

Here is a screenshot of the kind of bad rendering :

And here is a screenshot of the expected rendering :

Step to reproduce issue :

• The bad rendering is obtained with this model_3d_rendering_ko.xml
• The expected rendering is obtained with this model_3d_rendering_ok.xml

Background picture :

Acceptance criteria :

• Expected rendering obtained on both models,
• Expected rendering obtained on T42_St_barth_GJ_Final.xml model.