Decals Visible Through Walls

Reproduction Steps
Repro place:
ReproPlace.rbxl (24.9 KB)

  1. Download the repro file above.
  2. Move your camera position to the spawn part + a few studs above the spawn part and look at the gray wall.
  3. You will notice a faint line across the wall which shouldn’t be there.

Expected Behavior
If you are standing behind a wall, you shouldn’t be able to see floor decals from a part behind the wall.

Actual Behavior
In the image below, the decal appearance clips through a wall. When you look at a decal facing upwards from the side at >60 studs away, it clips through nearby parts.

Issue Area: Engine
Issue Type: Display
Impact: Moderate
Frequency: Often
Date First Experienced: 2021-09-30 00:09:00 (-05:00)
Date Last Experienced: 2021-09-30 00:09:00 (-05:00)
A private message is associated with this bug report

4 Likes

This is unfortunately a natural limitation of decals.

Decals are rendered separately from the part that they’re on top of. But, to make sure that they don’t z-fight with the part that they’re on top of, they’re rendered a tiny bit closer to the camera than the part… or if you’re looking at the decal from a super shallow angle like this, a large bit closer to the camera, enough to actually pop through the wall.

The effect is pretty subtle, so you should be able to mostly eliminate this either by making the wall thicker or not butting the decal up so close to the thin wall.

7 Likes

This has been a known compromise for a while. It would be good to re-assess this old issue to see if there are any new/unique methods to handle it. If we’re talking about immersion, that wall represents a foot thick wall already. Making house walls 2 feet thick to avoid seeing kitchen floor tiles from rendering through them is not a good solution today.

5 Likes