NVIDIAGameWorks
Lights create extra bloom when moving off-screen
Whenever a light moves off screen extra bloom is created at the intersection of the light and the edge of the viewport.
GPU: 4090 Driver: 367.13 Game build: All
Steps to reproduce the behavior:
- Run Portal with RTX
- Load into map testchmb_a_01
- Turn around and enter the elevator
- Position vertical lights at the edge of the screen
Expected: Extra bloom should not be added
https://github.com/NVIDIAGameWorks/rtx-remix/assets/130596284/abc05361-6499-49f3-858c-71d6a4d4e8a1
Bloom computation is using WRAP UV clamping, It doesn't seem like unintended behavior but a another clamp probably works best
Well I am pretty sure it is clamping to edge right now (not wrapping), and that was chosen I think because it lets lights that go off the screen partially still have a proper bloom contribution. If the mode is changed to something like clamp to a black border that would fix this artifact in some cases, but it'd cause new artifacts where the bloom near the edges of the screen is weaker than expected.
Ideally we'd just have data about the scene beyond the edge but without that information one or the other choice has to be made in how assumptions are made about the data. I think it's worth trying clamping to a black border though as having the bloom fade out a bit near the edges may be less visually distracting than what it's doing right now where it gets brighter in some cases instead.
