docs: HW-vs-SW Lumen measured — +20 ms/frame on the 760M

[proggeramlug]

Answers the question EN-023 and EN-058(c) have carried since the DXC work: granting EXPERIMENTAL_RAY_QUERY costs 14.4 vs 20.3 fps (~+20 ms/frame) on the shooter, same build, PT off — because SSGI/WSRC silently flip to the HW trace once the TLAS exists, and every skinned draw starts paying per-frame pre-skin + BLAS builds. The hiz-screen boot line is init-time only and misleading. Whether HW Lumen's quality is worth 20 ms is the product owner's call (needs GI screenshot A/B); BLOOM_FORCE_SW_GI=1 is the per-box escape hatch.

Summary by CodeRabbit

• Documentation
  • Added measured performance comparisons between hardware and software Lumen GI paths on the 760M.
  • Documented the observed quality-versus-frame-rate tradeoff to support default configuration decisions.
  • Clarified startup logging behavior and noted the available per-device option to force software GI.

[coderabbitai]

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📥 Commits

Reviewing files that changed from the base of the PR and between 314546d and b34c1f3.

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• docs/tickets.md

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📝 Walkthrough

Walkthrough

Adds an EN-052 follow-on note documenting measured hardware versus software Lumen performance on a 760M, backend logging timing, DXC-based enablement, and the BLOOM_FORCE_SW_GI=1 override.

Changes

Lumen measurements

Layer / File(s)	Summary
Measured Lumen comparison and follow-on findings docs/tickets.md	Documents the hardware and forced software GI PERFTEST results, DXC DLL enablement behavior, pre-TLAS backend logging, and the software GI workaround.

Estimated code review effort: 1 (Trivial) | ~2 minutes

Possibly related PRs

• Bloom-Engine/engine#75: Adds SSGI trace backend tracking and logging referenced by this note.
• Bloom-Engine/engine#83: Adds SSGI backend tier logging corresponding to the documented behavior.
• Bloom-Engine/engine#106: Updates the same ticket documentation around DXC/DXR fallback and HW/SW Lumen measurements.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch docs/hw-lumen-measured

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