Occluded DepthMode not respected with OpenGL

Bug Reports Engine Bugs
#1

This bug only came to my attention after one of my players reported that they saw the highlight object through walls when they shouldn’t have. So I spent a bit of time trying to figure out what happened and this seems to be the problem:

Reproduction Steps

  1. Turn on OpenGL in Roblox Studio (File > Studio Settings > Rendering > Graphics Mode > OpenGL)
  2. Restart Roblox Studio for the changes to be made
  3. Insert a part into a place file with a highlight object inside it
  4. Set the highlight object’s DepthMode to Occlude
  5. Look at the highlight object through any part and you’ll still see it

System Information

AMD Ryzen 7 2700X Eight-Core Processor @ 3.95 GHz, 16GB, NVIDIA GeForce RTX 2070 SUPER

Reproduction Files

Highlight Bug.rbxl (41.8 KB)

Expected Behavior

I expect the highlight object to be occluded with OpenGL when the DepthMode is set to Occluded.

occluded

Actual Behavior

The highlight object is not occluded when the DepthMode is set to Occluded and when the Rendering Mode is OpenGL.

not-occluded

On a side note, you can also see that the outline for the highlight object is also not rendered for OpenGL. I have no clue if that’s a limitation or not.

Issue Area: Engine
Issue Type: Display
Impact: High
Frequency: Constantly
Date First Experienced: 2022-05-18 13:05:00 (-07:00)
Date Last Experienced: 2022-05-20 11:05:00 (-07:00)

11 Likes
#2

This bug appears to also affect the native Vulkan renderer (not DXVK). Maybe this DepthMode just isn’t implemented for anything else.

Vulkan
Vulkan1372×700 42.5 KB

D3D11 not affected, even with DXVK.
D3D11 (DXVK)
D3D11 (DXVK)1372×700 36.4 KB

AMD RADV NAVI10
Vendor 1002 Device 731f
Driver 22.0.4 (92274692)
API 1.3.204

#3

Thanks for binging this up. We are currently investigating the issue and we’ll come back to you with updates when available.

6 Likes
#4

Thank you for the report. I was initially unable to reproduce this.
However I did by dynamically setting the Editor Quality Level. If you go below 17 (which disables MSAA) it works fine then when you go back to 17 or above it is no longer occluded properly as reported.

I will look into the root cause and get back once it is fixed.

1 Like
#5

Any update on this? I had to remove it from my game as people would gain an advantage from this bug.

#6

Still waiting on an update, any news?