#323: docs: the loupe's render plan, Before/After windows, drag timings

Co-Authored-By: Claude Sonnet 5.5 <[email protected]>

docs/control-protocol.md

@@ -30,7 +30,7 @@ mode ([mcp.md](mcp.md)) is a thin layer over this channel. Implementation:
 | `engine.commands` | — | Engine + UI commands: id, label, menu, shortcut, params doc, enabled |
 | `ui.menu.list` | — | Menu entries (flat: id, label, menu path, shortcut, enabled) |
 | `ui.menu.tree` | — | The menu bar as shown (File … Help): items `{id, params?, label, shortcut?, enabled, checked?}`, separators, submenus — the model behind the native macOS menu bar and the in-window menus |
-| `ui.inspect` | — | UI state, window, `loupe` (`source`, and `region: {full, window, pending}` when a zoomed view also renders the window on screen at the zoom scale), canvas/image rects, `scroll: {grid, filmstrip}` (scroll offsets in points, `null` until drawn), active photo, selection, perf (`frameMs` = layout, `logicMs` = per-frame logic before it, `updateMs` = both, `maxUpdateMs`, `fps`, render queue …, `gpu` = adapter in use, `gpuReason` = why renders don't use the GPU, `gpuFallback` = latest render redone on the CPU and why — see `docs/gpu-pipeline.md`), status, memory (bytes per cache, see `library.memory`; plus stage caches and textures), `export: {running: {total, done, current} \| null, last}`, `notices` (warnings waiting to be shown, e.g. a damaged settings file; OK = `button:noticeOk`), `quitPrompt` (why quitting was stopped: unsaved changes; `button:quitRetry` / `button:quitAnyway` / `button:quitCancel`), `import: {done, total, imported, cancelled} \| null` (an import runs on a worker thread), `tasks` (other background work: `Find Missing Photos`, `Auto Import`) |
+| `ui.inspect` | — | UI state, window, `loupe` (`source`, and `region: {full, window, pending}` when a zoomed view also renders the window on screen at no more than 100 % — `full` is the frame it is cut from, `window` its `[x, y, w, h]` — and `regionBefore` for the Before side of a Before/After view), canvas/image rects, `scroll: {grid, filmstrip}` (scroll offsets in points, `null` until drawn), active photo, selection, perf (`frameMs` = layout, `logicMs` = per-frame logic before it, `updateMs` = both, `maxUpdateMs`, `fps`, render queue …, `gpu` = adapter in use, `gpuReason` = why renders don't use the GPU, `gpuFallback` = latest render redone on the CPU and why — see `docs/gpu-pipeline.md`), status, memory (bytes per cache, see `library.memory`; plus stage caches and textures), `export: {running: {total, done, current} \| null, last}`, `notices` (warnings waiting to be shown, e.g. a damaged settings file; OK = `button:noticeOk`), `quitPrompt` (why quitting was stopped: unsaved changes; `button:quitRetry` / `button:quitAnyway` / `button:quitCancel`), `import: {done, total, imported, cancelled} \| null` (an import runs on a worker thread), `tasks` (other background work: `Find Missing Photos`, `Auto Import`) |
 | `ui.widgets` | `{filter?}` | On-screen widgets `{id, rect: [x, y, w, h]}` (screen points) |
 | `ui.clickWidget` / `ui.dragWidget` / `ui.hoverWidget` | `{id, count?, fx?, fy?}` / `{id, toX?, toY?, dx?, dy?, steps?}` / `{id, fx?, fy?}` | Real egui input on a widget (hover: the pointer rests on it, e.g. for preset/profile previews) |
 | `ui.move` / `ui.click` / `ui.drag` | `{x, y, count?, button?}` / `{x, y, toX, toY, steps?}` | Raw pointer input, screen points |

docs/gpu-pipeline.md

@@ -212,6 +212,7 @@ the device on their first GPU render. `lightcraft_gpu::ready()` asks without blo
   developed image in ~50 ms.
 
 ## Memory (M5.6)
+A view's stages keep an uploaded source only up to 96 MB (a Preview-level source); a bigger one (the original a zoom window is cut from) is uploaded for the render alone, so the stages hold the window's own pixels (issue #323: otherwise a 288 MB upload counted against the stage budget on every tick of a drag).
 - `library.memory` reports what the engine's caches hold (decoded thumbnail / preview / full-size
   sources, rendered previews) and the GPU renderer's device buffers (allocated, of which pooled
   and retired); `ui.inspect` → `memory` adds the loupe's stage caches (CPU images, GPU buffers)

docs/parity.md

@@ -71,8 +71,8 @@ Take the first one nobody is working on.
    colour-filter layout, fixed in #85 by reading the file's own tag).
 4. **LR-BEHAV-RENDER-FIDELITY** (P1): a side-by-side fidelity suite against Lightroom renders (kept local in `plan/`),
    then tune tone, highlights, texture/clarity/dehaze, NR and sharpening against it.
-4b. **LR-VIEW-ZOOM** (P0): finish the sharp zoomed views of issue #323: windows for Before/After, compare, overlays and
-   soft proofing; check sharpness and the wide-stage margin on real raw photos (only synthetic scenes so far).
+4b. **LR-VIEW-ZOOM** (P0): finish the sharp zoomed views of issue #323: windows for compare, overlays and soft proofing
+   (Before/After has them); check sharpness and the wide-stage margin on real raw photos (only synthetic scenes so far).
 5. **LR-EDIT-OPTICS-PROFILE** (P1): a lens-profile database of our own (corrections embedded in DNG files and the
    distortion correction Panasonic / Leica cameras record in RW2 / RWL files work today; issue #256).
 6. **AI masks and Enhance** (LR-MASK-SUBJECT / SKY / PEOPLE / OBJECTS, LR-EDIT-DETAIL-DENOISE, SUPERRES, LENSBLUR):
@@ -185,7 +185,7 @@ under the UI command that wraps it (a no-op error); the UI command now wins.
 | LR-VIEW-EDIT | Edit view | P0 | ✅ | `cmd:panel.edit` | |
 | LR-VIEW-FULLSCREEN | Full-screen preview | P1 | ✅ | `cmd:view.fullScreenPreview`, `cmd:view.enterFullScreen` | photo on black, arrows step, Esc exits; ⇧⌘F window full screen |
 | LR-VIEW-FILMSTRIP | Filmstrip | P0 | ✅ | `cmd:view.filmstrip`, `crates/ui-egui/src/panels/detail.rs` | the photo context menu on right-click; the mouse wheel scrolls it sideways; it follows the active photo only when that changes (centred if off screen), so a scrolled strip stays put; every selected photo is highlighted, the active one framed in white, as in the grid |
-| LR-VIEW-ZOOM | Zoom & pan | P0 | 🟡 | `cmd:view.zoomFit`, `cmd:view.zoom100`, `cmd:view.zoomIn`, `cmd:view.zoomOut`, `cmd:view.zoomToggle`, `cmd:view.clickZoom`, `cmd:view.navigate`, `crates/ui-egui/src/panels/detail.rs`, `crates/ui-egui/src/headless.rs` | continuous native pinch / modifier-wheel zoom (Fit–800%, anchored under the pointer), two-finger scroll / touch pan with edge limits; Detail (including tools, Before/After and full-screen preview), Compare and Reference; fractional percentages preserve small gestures; image, picker and targeted-adjustment cursors stay steady between gesture events; keyboard steps 25–800 % (not 6–1600 %); Fill in the bottom bar; click / Z / Space eases to the chosen ratio (1:1 default, 2:1, 3:1, 4:1, 8:1). Past what one whole-frame render holds (the photo's own pixels, 8192 px ceiling, or the Preview size cap) the loupe also renders just the window on screen at the zoom scale (`RenderRequest::window`, `Session::region_job`, `crates/ui-egui/src/region.rs`; issue #323), so 1:1 and 2:1–8:1 are sharp at any photo size. Windows render on the GPU like whole frames (equivalence-tested against the CPU), in the browser build too (capped at 3072 px a side there), and are not made during a slider drag (the draft shows) nor while comparing, hovering a look, soft-proofing or showing an overlay. Spots and Auto Mask brushes work while what a window reads fits one render (8192 px along an axis, 4096 in the browser): the window grows to hold the spot and its source patch, or the dabs near it, and if that would take more (a clone from far away at 8:1) the loupe keeps the whole-frame render instead, and spots with an automatic source pick it from a fixed-size render of the whole frame (so a window's choice can differ from a whole-frame render's, which picks at its own resolution). The wide stages (dehaze, clarity, highlights/shadows base) and Refine Edges on masks read a window margin capped at 768 px; measured on hard-edged blocks that costs at most a few levels at 8:1. the histogram and Navigator come from the whole-frame render |
+| LR-VIEW-ZOOM | Zoom & pan | P0 | 🟡 | `cmd:view.zoomFit`, `cmd:view.zoom100`, `cmd:view.zoomIn`, `cmd:view.zoomOut`, `cmd:view.zoomToggle`, `cmd:view.clickZoom`, `cmd:view.navigate`, `crates/ui-egui/src/panels/detail.rs`, `crates/ui-egui/src/headless.rs` | continuous native pinch / modifier-wheel zoom (Fit–800%, anchored under the pointer), two-finger scroll / touch pan with edge limits; Detail (including tools, Before/After and full-screen preview), Compare and Reference; fractional percentages preserve small gestures; image, picker and targeted-adjustment cursors stay steady between gesture events; keyboard steps 25–800 % (not 6–1600 %); Fill in the bottom bar; click / Z / Space eases to the chosen ratio (1:1 default, 2:1, 3:1, 4:1, 8:1). The loupe's cost follows the canvas, not the zoom (issue #323): the whole frame is rendered at about canvas size (at most the 2560 px preview source level, the Preview size limit and the GPU's texture side), and once the view is zoomed well past that (more than 25 %) the window on screen is rendered too, cut from a frame of at most the photo's own pixels, so beyond 100 % the GPU magnifies it (`region::plan`, `RenderRequest::window`, `Session::region_job`, `crates/ui-egui/src/region.rs`); 1:1 and 2:1–8:1 are sharp at any photo size, a slider drag drafts both renders (7–12 ms a tick at 100 % and 400 % of a 24 MP photo on an M1 Max, `profile_slider_drag`), a continuous pinch holds the render sizes until it is quiet, and a fit view (also on a Retina Mac) never decodes the original. Before/After (side by side, stacked, `\\` and both wipes) gets the same windows on both sides. Windows render on the GPU like whole frames (equivalence-tested against the CPU), in the browser build too (windows no wider than its GPU's texture side, at most 3072 px), and are not made while hovering a look, soft-proofing or showing an overlay, nor over a picture that is not the frame (an unsupported raw's embedded JPEG with another crop). No texture is larger than the GPU allows. The per-view stage caches count against a quarter of the memory budget. Spots and Auto Mask brushes work while what a window reads fits one render (8192 px along an axis, 4096 in the browser): the window grows to hold the spot and its source patch, or the dabs near it, and if that would take more (a clone from far away at 8:1) the loupe keeps the whole-frame render instead, and spots with an automatic source pick it from a fixed-size render of the whole frame (so a window's choice can differ from a whole-frame render's, which picks at its own resolution). The wide stages (dehaze, clarity, highlights/shadows base) and Refine Edges on masks read a window margin capped at 768 px; measured on hard-edged blocks that costs at most a few levels at 8:1. the histogram and Navigator come from the whole-frame render |
 | LR-VIEW-NAVIGATOR | Navigator mini map | P1 | ✅ | `cmd:view.navigator`, `crates/ui-egui/src/panels/detail.rs` | shown while zoomed (bottom right); click/drag pans |
 | LR-VIEW-BEFOREAFTER | Before / after | P0 | ✅ | `cmd:view.showOriginal`, `cmd:view.beforeAfter`, `cmd:view.beforeAfterSplit`, `cmd:view.beforeAfterTopBottom`, `cmd:view.beforeAfterSplitTopBottom`, `cmd:beforeAfter.setBefore`, `cmd:beforeAfter.copyAfterToBefore`, `cmd:beforeAfter.copyBeforeToAfter`, `cmd:beforeAfter.swap`, `cmd:beforeAfter.resetBefore` | all four layouts; before = the import state (defaults + import preset) or a chosen history step / version / the current settings; copy and swap (View → Before/After Settings, History row menu). The chosen before lasts for the session |
 | LR-VIEW-COMPARE | Compare two photos | P1 | ✅ | `cmd:view.compare`, `cmd:compare.swap`, `cmd:compare.makeSelect`, `crates/ui-egui/src/panels/compare.rs` | select / candidate, synced zoom + pan, arrows move the candidate; no zoom-link toggle |
@@ -480,7 +480,7 @@ under the UI command that wraps it (a no-op error); the UI command now wins.
 | LR-PREF-LOCALSTORAGE | Storage & cache | P1 | ✅ | `cmd:library.preferences`, `cmd:library.clearPreviews`, `cmd:library.compact` | thumbnail cache size + clear in Settings → Performance; library location + Open Library… in General |
 | LR-PREF-ACCOUNT | Account | OOS | 🚫 | | |
 | LR-PREF-INTERFACE | Interface options | P1 | ✅ | `cmd:app.settings` | filmstrip names/badges, grid badges (auto/always/never), square-grid names, navigator, info overlay |
-| LR-PREF-PERFORMANCE | GPU / performance | P1 | ✅ | `cmd:app.gpu`, `cmd:app.memoryBudget`, `cmd:app.settings` | GPU on/off, preview size (Automatic = the size the loupe is drawn at, up to the photo's own pixels and an 8192 px ceiling; or a 1600–5120 px cap; issue #323), memory budget, thumbnail cache size in Settings |
+| LR-PREF-PERFORMANCE | GPU / performance | P1 | ✅ | `cmd:app.gpu`, `cmd:app.memoryBudget`, `cmd:app.settings` | GPU on/off, preview size (Automatic = the whole-frame loupe render at canvas size, up to 2560 px; or a 1600–5120 px cap on it; zoomed views add a window at up to 100 %, issue #323), memory budget (the per-view stage caches count against a quarter of it), thumbnail cache size in Settings |
 | LR-PREF-PEOPLE | Face recognition | P2 | ⬜ | | |
 | LR-PREF-WATERMARK | Watermark settings | P1 | ✅ | `cmd:export.savePreset`, `crates/ui-egui/src/panels/dialogs.rs` | set in the Export dialog; kept with Export with Previous and in saved export presets |
 | LR-PREF-SHORTCUTS | Shortcut customisation | — | ✅ | `cmd:app.setShortcut`, `cmd:app.resetShortcuts`, `crates/ui-egui/src/panels/keymap.rs` | an extra (the reference app has no keymap editor): Help ▸ Keyboard Shortcuts (⌘/) lists every command; click a shortcut and press the new keys (Esc cancels), × removes, ↺ restores, Reset All; a key another command had moves over; saved in `ui.json`; native menu accelerators follow. Rating/label digits and secondary keys are listed read-only and yield to a key given to a command |