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+# Round 4: Cinema
+
+## The juror's critique (before)
+
+Shots: `round4/before-*.webp`, `round4/before-sheet.webp`.
+
+- **Murky world.** The whole frame sat in one purple haze with no true blacks and no contrast range. The sun was a pale, flat disc that looked like clip-art. Nothing in the frame said "night".
+- **Empty destination.** The road ended at nothing. Wireframe hills and grey districts read like a synthwave template. Nothing pulled the eye to the vanishing point.
+- **A lonely road.** No other traffic and no light moving through the frame, so speed came only from the grid scrolling.
+- **One card, eight times.** Every chapter used the same rounded glass card over the world. Chapter changes were invisible: the panel swapped and the world carried on unchanged.
+- **Generic hero.** A standard gradient name with no title-card moment and no opening shot.
+- **Flat sound.** The soundtrack did not react when you took an exit.
+
+## The transformation
+
+The site now plays like the opening of a film: crane shot, title card, then a drive where every chapter is an exit you physically pass through.
+
+1. **Film grade and lens (all tiers).**
+   - `src/scene/cinematic-grade.ts` swaps three's CustomToneMapping chunk for ACES followed by a deeper toe, an S-curve, cool shadows, warm highlights and a saturation lift. The low tier, which has no post-processing, gets the same grade.
+   - On post-processing tiers, `LensFinishPass` replaces OutputPass one for one and allocates no extra render target. It adds:
+     - chromatic aberration at the frame edges;
+     - an anamorphic blue streak sampled from a bloom mip that already exists;
+     - vignette and grain;
+     - letterbox bars and an exposure flash.
+2. **The destination.** `world/skyline.ts` is a single procedural plane that draws a two-layer city silhouette against the sun. It has lit windows, sun-caught roof edges and blinking masts, uses one draw call and no texture.
+3. **Traffic.** `world/traffic.ts` draws taillight pairs, long-exposure trails and wet-road pools.
+   - Fast cars pull away when you idle. Scroll fast and you overtake trucks.
+   - Three instanced draws; vehicle count is 14, 10 or 7 depending on tier.
+4. **Wet road.** The asphalt now picks up a sun glare column, headlight throw from the car, and pylon reflections that travel with the drive.
+5. **The sun.** A saturated vermilion-to-gold disc, held below the ACES shoulder so it no longer washes out to cream.
+6. **Opening crane.** On a fresh load at the top of the page, the camera starts high and looking at the sun, then cranes down to the car over 4.2 s with letterbox bars. Scrolling speeds it up five times.
+7. **Exit gates (the chapter cut).**
+   - On every chapter change, nine light gates in the next chapter's accent colour rush past in about two seconds. The frame flashes slightly and the field of view opens.
+   - The audio answers with a pass-by: a band-passed air sweep that pans left to right. Its nodes are allocated in advance, so a chapter change only schedules automation.
+8. **Title card and night plates.**
+   - The hero name is a large Outrun chrome title with a clip-path reveal that runs only under `prefers-reduced-motion: no-preference`.
+   - Panels became sharp-cornered dark plates with an accent rule, a hairline and crop marks.
+   - The broken one-word-per-line portrait-strip captions are fixed at ≥1100px.
+
+## Evidence
+
+- Typecheck clean. Vitest: 684 of 684 passed.
+- `build:preview` budgets, with `violations: []`:
+
+  | Budget | Size |
+  | --- | --- |
+  | Initial JS | 95.2 KB |
+  | HTML + critical CSS | 40.9 KB |
+  | Fonts | 69.0 KB |
+  | First live scene | 322.8 KB |
+  | Deferred non-video | 596 KB |
+
+- No new textures or render targets, so GPU allocation is unchanged.
+- FPS on Intel Arc iGPU, headed, before → after:
+
+  | Section | Before | After |
+  | --- | --- | --- |
+  | start | 168 | 152 |
+  | infrastructure | 187 | 176 |
+  | selected-builds | 185 | 173 |
+  | toolkit | 175 | 179 |
+  | contact | 200 | 184 |
+
+  p95 frame time is 8.4 ms everywhere.
+- After shots: `round4/after-*.webp`, `round4/after-sheet.webp`, `round4/after-mobile-sheet.webp`.
+
+## Honest regressions and open items
+
+- FPS is about 6–9% lower, mainly from the lens pass and the traffic.
+- The first frame at `start` has one worst-case spike of about 196 ms from shader compiles.
+- The letterbox and lens effects appear only on post-processing tiers. The low tier gets the grade, the skyline, the gates and reduced traffic.
+- The hero copy at 390 px still overlaps the car once the crane settles. This was true before this round too.
+- Not done this round:
+  - a new car model or Blender asset pass;
+  - a nav and soundtrack-button redesign;
+  - consolidating the 12 stylesheets (the new CSS is one appended block in `route.css`).
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