fix(ibl): crash when dynamic cubemaps disabled

[jiayev]

This pull request updates the IBL prepass logic to better handle cases where dynamic cubemaps are not loaded, preventing potential null dereferences in shader resource views.

Resource management improvements:

• In src/Features/IBL.cpp, the assignment of envTexture and envReflectionsTexture is changed from const auto& to auto& to allow modification if needed.
• When constructing the srvs array, the shader resource views for environment textures are now conditionally set to nullptr if dynamicCubemaps.loaded is false, improving robustness against missing resources.

Summary by CodeRabbit

• Bug Fixes

  • Environment textures are now only bound when dynamic cubemaps are available, preventing flickering or incorrect reflections during loading.

• Performance

  • Avoids unnecessary binding of environment resources when not loaded, reducing GPU work and improving stability during startup and scene changes.

[coderabbitai]

Walkthrough

The prepass in src/Features/IBL.cpp now makes local references to environment textures mutable and conditionally binds envTexture and envReflectionsTexture SRVs only when dynamicCubemaps.loaded is true; otherwise those SRV slots receive nullptr. No public interfaces changed.

Changes

Cohort / File(s)	Summary
IBL prepass SRV binding src/Features/IBL.cpp	Change envTexture/envReflectionsTexture from const auto& to auto&. Initialize SRV array entries for environment textures to (dynamicCubemaps.loaded && envTexture) ? envTexture->srv.get() : nullptr and (dynamicCubemaps.loaded && envReflectionsTexture) ? envReflectionsTexture->srv.get() : nullptr; other prepass logic unchanged.

Sequence Diagram(s)

sequenceDiagram
  autonumber
  participant Prepass as IBL::Prepass
  participant Env as Environment Textures
  participant CS as Compute Shader

  Prepass->>Env: Acquire envTexture, envReflectionsTexture (auto& mutable refs)
  alt dynamicCubemaps.loaded == true
    Prepass->>CS: Bind SRVs [..., envTexture.srv, envReflectionsTexture.srv, ...]
    note right of CS #DFF2E1: Env textures available for sampling
  else
    Prepass->>CS: Bind SRVs [..., null, null, ...]
    note right of CS #FEEFEF: Env sampling disabled (null SRVs)
  end
  Prepass->>CS: Dispatch compute shader

Loading

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related PRs

• refactor(ibl): smooth blend dynamic cubemaps #1425 — Modifies IBL handling and dynamic cubemap usage in src/Features/IBL.cpp, touching similar env/reflection binding behavior.
• feat(ibl): use static ibl textures for outworld objects #1434 — Alters prepass SRV binding logic in src/Features/IBL.cpp, related to which IBL textures are bound and when.
• fix(dynamic cubemaps): use same cubemap for non/deferred #1376 — Changes how environment cubemap resources are used with dynamic cubemaps; relevant to consumption of env textures.

Suggested reviewers

• alandtse
• doodlum

Poem

I hop through code with careful paws,
I bind the skies only when they’re gauged,
If cubemaps load, the stars applause,
If not, I leave those slots unstaged. 🐇✨

---

📜 Recent review details

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 5173d0e and 39addb7.

📒 Files selected for processing (1)

• src/Features/IBL.cpp (1 hunks)

🚧 Files skipped from review as they are similar to previous changes (1)

• src/Features/IBL.cpp

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

• GitHub Check: Build plugin and addons

✨ Finishing Touches

• 📝 Generate Docstrings

🧪 Generate unit tests

• Create PR with unit tests
• Post copyable unit tests in a comment

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[github-actions]

Using provided base ref: 256a385
Using base ref: 256a385
Base commit date: 2025-08-29T00:02:23-07:00 (Friday, August 29, 2025 12:02 AM)
No actionable suggestions for changed features.

[coderabbitai]

Actionable comments posted: 1

🧹 Nitpick comments (1)

src/Features/IBL.cpp (1)

72-73: Non-const refs seem unnecessary here

These locals aren’t mutated. Unless something below actually writes to them, keep them const for clarity, or justify the mutability in a comment.

📜 Review details

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

💡 Knowledge Base configuration:

• MCP integration is disabled by default for public repositories
• Jira integration is disabled by default for public repositories
• Linear integration is disabled by default for public repositories

You can enable these sources in your CodeRabbit configuration.

📥 Commits

Reviewing files that changed from the base of the PR and between 256a385 and 5173d0e.

📒 Files selected for processing (1)

• src/Features/IBL.cpp (1 hunks)

🧰 Additional context used

📓 Path-based instructions (2)

**/*.{cpp,cxx,cc,c,h,hpp,hxx,hlsl,hlsli,fx,fxh,py}

📄 CodeRabbit inference engine (.github/copilot-instructions.md)

Do not include TODO/FIXME placeholders; provide complete, working solutions

Files:

• src/Features/IBL.cpp

src/**/*.{cpp,cxx,cc,h,hpp,hxx}

📄 CodeRabbit inference engine (.github/copilot-instructions.md)

src/**/*.{cpp,cxx,cc,h,hpp,hxx}: Ensure SE/AE/VR runtime compatibility; use runtime detection patterns (e.g., REL::RelocateMember())
Include robust error handling and resource management with graceful degradation in the plugin code

Files:

• src/Features/IBL.cpp

🧠 Learnings (2)

📓 Common learnings

Learnt from: jiayev
PR: doodlum/skyrim-community-shaders#0
File: :0-0
Timestamp: 2025-07-18T15:21:03.641Z
Learning: In the skyrim-community-shaders rendering pipeline, materials with alpha < 1 or alpha blending enabled are rendered in non-deferred mode rather than deferred mode. This means issues with dynamic cubemaps on transparent materials are actually non-deferred rendering issues.

Learnt from: alandtse
PR: doodlum/skyrim-community-shaders#0
File: :0-0
Timestamp: 2025-07-05T05:20:45.823Z
Learning: In the skyrim-community-shaders repository, file deletion error handling improvements that replace existence checks and try-catch blocks with std::filesystem::remove error-code-based approaches are considered bug fixes rather than refactoring, as they address inadequate error handling and misleading log messages.

Learnt from: jiayev
PR: doodlum/skyrim-community-shaders#0
File: :0-0
Timestamp: 2025-08-03T18:37:19.690Z
Learning: ISReflectionsRayTracing.hlsl and ISWorldMap.hlsl in the skyrim-community-shaders repository are image-space post-processing shaders that perform color sampling and blending operations that need proper linear color space handling for the linear lighting system. ISReflectionsRayTracing handles screen-space reflections and should use conditional Color::IrradianceToLinear/Gamma conversions similar to ISCompositeLensFlareVolumetricLighting.hlsl. ISWorldMap performs 7x7 color accumulation that should be done in linear space similar to the pattern used in ISSAOComposite.hlsl.

📚 Learning: 2025-08-03T18:37:19.690Z

Learnt from: jiayev
PR: doodlum/skyrim-community-shaders#0
File: :0-0
Timestamp: 2025-08-03T18:37:19.690Z
Learning: ISReflectionsRayTracing.hlsl and ISWorldMap.hlsl in the skyrim-community-shaders repository are image-space post-processing shaders that perform color sampling and blending operations that need proper linear color space handling for the linear lighting system. ISReflectionsRayTracing handles screen-space reflections and should use conditional Color::IrradianceToLinear/Gamma conversions similar to ISCompositeLensFlareVolumetricLighting.hlsl. ISWorldMap performs 7x7 color accumulation that should be done in linear space similar to the pattern used in ISSAOComposite.hlsl.

Applied to files:

• src/Features/IBL.cpp

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

• GitHub Check: Build plugin and addons

🔇 Additional comments (1)

src/Features/IBL.cpp (1)

75-75: Confirm shader recompilation on dynamicCubemaps.loaded toggle

I couldn’t find where GetDiffuseIBLCS() is recompiled or ClearShaderCache() is called when dynamicCubemaps.loaded changes. Please verify that toggling this flag triggers a shader cache clear or recompile so the bound SRVs always match shader expectations.

[github-actions]

✅ A pre-release build is available for this PR:
Download

[alandtse]

Please review all AI comments and mark as resolved once done.