refactor(compositor): carry the tilted plane's depth gradient to mode 8

[EtienneLescot]

Plumbing for depth of field: mode 8 receives the tilted plane depth gradient.

Chantier 3D, PR 5a. Spec complète et branche d intégration : #682.

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Summary by CodeRabbit

• New Features

  • Tilted-screen rendering now calculates and passes depth and focus information based on the active zoom focus and drawn content area.
  • Focus positioning remains aligned with cropped and cover-scaled content.

• Bug Fixes

  • Corrected depth-focus calculations for tilted rendering, including non-centered focus points.

• Tests

  • Added coverage for depth calculations, crop handling, and rendering stability across supported platforms.

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ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Advanced

Run ID: 63c08eb1-3654-4ac1-a5de-21ec69042b69

📥 Commits

Reviewing files that changed from the base of the PR and between 0834a66 and 480e98c.

⛔ Files ignored due to path filters (1)

• crates/compositor/src/shaders.hlsl is excluded by !**/*.hlsl

📒 Files selected for processing (8)

• crates/compositor/src/compositor_linux.rs
• crates/compositor/src/compositor_macos.rs
• crates/compositor/src/compositor_windows.rs
• crates/compositor/src/frame_geometry.rs
• crates/compositor/src/regions.rs
• crates/compositor/src/shaders.metal
• crates/compositor/src/vk_shaders/layer.wgsl
• crates/compositor/tests/tilted_depth_slot_inert.rs

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📝 Walkthrough

Walkthrough

The change resolves the zoom focus within the drawn cut, computes tilted-plane depth data, and passes it through all compositor backends. The shader documents the new mb layout but does not read the values yet. Unit and Windows integration tests cover the data and unchanged output.

Changes

Tilted depth focus

Layer / File(s)	Summary
Resolve focus in the drawn cut crates/compositor/src/frame_geometry.rs	FrameGeometry now stores focus_plane. Frame planning maps and clamps the focus within the drawn cut. Tests cover shifted, cover-cropped, out-of-bounds, and non-finite focus values.
Compute tilted-plane depth crates/compositor/src/regions.rs	TiltedQuad now stores closed-form depth coefficients and provides depth_mb, which returns plane gradients, focus depth, and k = 0. Tests compare the computed depth with rotated geometry across presets and shapes.
Pass depth data to tilted rendering crates/compositor/src/compositor_linux.rs, crates/compositor/src/compositor_macos.rs, crates/compositor/src/compositor_windows.rs, crates/compositor/src/shaders.metal, crates/compositor/src/vk_shaders/layer.wgsl, crates/compositor/tests/tilted_depth_slot_inert.rs	All platform paths pass focus_plane and depth_mb values through mb. Shader comments document the layout, and a Windows integration test verifies unchanged rendered bytes.

Priority: ⬇️ Low

Estimated code review effort: 3 (Moderate) | ~20 minutes

Change: Refactor

Suggested reviewers: beetix

Merge Risk: ⚪ Minimal · up to 480e9

The change prepares focus-relative tilted-depth data without changing rendered output, and no actionable merge risk is established.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description briefly states the change and references related work, but it omits the required template sections for related issue, change type, release impact, desktop impact, screenshots or video,…	Complete the required template sections. Use an accepted related-issue format such as "Refs #682", select the applicable change type, release impact, and desktop impact, and document screenshots or video and testing details.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the compositor refactor that carries the tilted plane depth gradient to mode 8.
Docstring Coverage	✅ Passed	Docstring coverage is 80.65% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 31 functions across 6 files. (2 skipped: 2 …
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

Full details: Description check

Explanation

The description briefly states the change and references related work, but it omits the required template sections for related issue, change type, release impact, desktop impact, screenshots or video, and testing.

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[EtienneLescot]

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[EtienneLescot]

Intégrée dans integration/chantier-3d (#682) avec ses corrections de revue CodeRabbit ; le chantier avance désormais dans cette seule PR.