Issue with Passthrough Layer occluding gsplat regardless of depth in Meta SDK

[domain808]

The Passthrough Layer in the Meta SDK is not functioning as expected.

In my Unity environment, interactions with other 3D objects and Unity's Alpha Materials work perfectly fine, and I have no issues implementing complex mixed environments.

However, I am facing a problem when trying to create a "basement" effect in Mixed Reality. Typically, I implement this by using a Passthrough Layer on the floor to mask the surface. But when I do this, the gsplat (Gaussian Splats) gets occluded by the Passthrough Layer regardless of its spatial position or depth.

Is there a workaround for this? I need the Passthrough Layer to respect the depth of the Gaussian Splats to properly visualize the underground space.

Unity Inspector

[wuyize25]

Unfortunately I don't have a Meta Quest on hand to test the issue you described. What follows is just my speculation. Gsplat objects should behave like ordinary translucent objects: their render order is determined by the depth of their bounding-box center, and they do not write to the depth buffer. I see you've set the passthrough layer's render queue very high (5000), while a normal translucent object's render queue is 3000 — are you sure a normal translucent object wouldn't be occluded by it?

[domain808]

A render queue of 5000 is the default configuration in the Meta SDK. This architecture is tailored to Unity's standard 3D environment and remains compatible with other 3D settings.

When applied to a surface or object, it functions by revealing the real world via Passthrough. My approach involves creating a room on a lower level and placing a Plane Object with a Passthrough Layer above it. By adding stairs or a hole, the real world is blended into the scene.

Android XR appears to have a similar Passthrough Layer to the Meta SDK. I am wondering where I can find a solution or documentation to achieve this same effect on that platform.