Shadow issues with right-handed system and back-face culling


I am in the process of upgrading our project from Babylon 6 to 7, but I am having issues with the ceilings of our rooms not casting shadows after upgrading.

Example playground:
test light | Babylon.js Playground (

I want to be able to see through the ceiling from above, but still have the ceiling cast a shadow. The playground works in Babylon 6 and below but in Babylon 7 there is no shadow cast. Is this related to the breaking changes made in 7.11?

In fact, it’s a bug in versions prior to the one in which we made the correction (7.6.2, in this PR).

The plane is not visible from the light (what you see is the frustum of the light):

You don’t see the plane in this picture, because of the value of sideOrientation. As a result, the plane will not be rendered in the shadow map and will therefore not generate shadows.

If you change the orientation, the plane will be visible, as well as the shadow:

The easiest way to fix it in your PG, is to set boxMaterial.backFaceCulling = false. Or you can use a thin box instead of a plane for the mesh.