Squash Odysseus development history

plans/photo-editor-remaining-scope.md

@@ -0,0 +1,159 @@
+# Photo Editor Remaining Scope
+
+Date: 2026-08-29
+
+## Current verdict
+
+Odysseus is now a credible layered everyday editor, not an editor mockup. The
+first nine roadmap phases are implemented: professional transform geometry,
+shared direct-manipulation sessions, retained placed content, unified
+selections and masks, a reusable brush/retouch engine, and retained text and
+shape layers.
+
+Phase 10 is functionally advanced but not closed. First-class adjustment layers
+now support Levels, Curves, Exposure, White Balance, Brightness/Contrast,
+Hue/Saturation/Lightness, Color Balance, Selective Color, and Gradient Map.
+They participate in clipping, groups, masks, visibility, opacity, history, the
+v14 document format, and flattening. Retained effects have since been added as
+a separate ordered stack with Gaussian Blur, Color Overlay, Drop Shadow, and
+Stroke, including editable colors, visibility, opacity, reorder, rasterize,
+history, persistence, and migration.
+
+Practical readiness estimate:
+
+- Everyday layered photo editing: **about 88%**
+- Dependable professional v1 described by the roadmap: **about 62%**
+- Broad Photoshop/Photopea feature parity: **about 50%**
+
+The remaining gap is dominated by large-document rendering outside the live
+composite path, workspace consolidation, interchange/color policy, and release
+proof rather than basic canvas tools.
+
+## Verification snapshot
+
+- The focused editor unit suite currently passes **31 tests** in Docker.
+- The full photo-editor browser suite currently has **41 passing workflows**;
+  the nested-group selection workflow initially exposed a row-hit regression,
+  which now passes on isolated rerun after the slider-selection fix. The new
+  group-effects workflow also passes.
+- The new adjustment tests exercise deterministic pixel math, nested parameter
+  normalization, retained metadata, undo/redo, clipping, masks, and draft
+  reopen.
+- The latest editor changes have not yet been rebuilt into the live `7011`
+  container.
+
+## Close Phase 10
+
+This is the immediate release slice.
+
+1. Finish the bounded preview path for large documents. Downsampled previews
+   now keep control movement responsive and full resolution is restored for
+   commit/export. Live worker composites now use generation checks, latest-only
+   coalescing, and close/reopen invalidation; extend the same guarantees to
+   remaining preview paths.
+2. Add flattened-export versus reopened-project pixel comparisons for every
+   adjustment family, including groups, clipping, masks, blend mode, and
+   partial opacity.
+3. Validate the color algorithms visually. White Balance and Selective Color
+   are currently deterministic approximations, not color-managed photographic
+   transforms.
+4. Test every adjustment popup on phone and desktop viewports, including tall
+   popups, color inputs, drag, Reset, Apply, Cancel, and Escape.
+5. Decide the migration path for the older per-raster `adjLayers` stack. It can
+   remain readable for compatibility, but new UI should converge on first-class
+   adjustment layers instead of maintaining two competing concepts.
+6. Bump static cache versions, rebuild the live container, and run a short
+   visual smoke test on `7011`.
+
+## Phase 11: Retained effects and filters
+
+The retained-effects slice is implemented for raster/placed/text/shape-compatible
+layer output: Gaussian Blur, Sharpen, Color Overlay, Drop Shadow, and Stroke
+have editable colors/parameters, visibility, opacity, reorder, rasterize,
+history, migration, and reopen support. Effect-specific masks, presets, and
+group-level effects are also implemented and covered by focused browser tests.
+Remaining work is:
+
+1. Extend worker coverage to serialization and remaining preview paths.
+   Thumbnail encoding, retained-effect rasterization, and live composite
+   rendering now use a worker where OffscreenCanvas is available, with
+   synchronous compatibility fallbacks. Generation invalidation, latest-only
+   coalescing, and CPU loop cancellation protect live rendering.
+2. Add explicit group-effect blend/ordering tests for nested groups and
+   non-default blend modes, plus visual comparisons for effect stacks.
+
+Introduce the renderer/worker cancellation boundary here rather than adding
+more synchronous full-canvas filters that Phase 14 must immediately replace.
+
+## Phase 12: Professional workspace
+
+Consolidate fragmented popups into one contextual properties surface. Persist
+panel layout by device class, add command search, expose stable document status,
+and support multiple open documents with independent history, zoom, pan, and
+selection. Mobile should use canvas-first sheets rather than compressed desktop
+panels.
+
+## Phase 13: Interchange and export
+
+Harden orientation, transparency, metadata, and color behavior for PNG, JPEG,
+and WebP first. Add copy/paste and drag/drop through placed layers. Treat
+layered formats as explicit compatibility projects: unsupported PSD/TIFF/HEIC
+features must be reported, never silently discarded. Odysseus project files
+remain the lossless source of truth.
+
+## Phase 14: Performance and recovery
+
+Move remaining preview/pixel paths into workers. Thumbnail encoding,
+autosave serialization, adjustment rendering, and retained-effect rendering
+now have worker-backed paths with compatibility fallbacks. Add
+dirty-region compositing, reusable render surfaces, cancellation tokens,
+operation telemetry, a documented surface/history budget, autosave generations,
+and a checked-in 4K multi-layer benchmark.
+
+This phase is the main architectural risk. Canvas 2D remains a valid
+compatibility renderer, but full-document synchronous passes will not scale to
+professional documents.
+
+## Phase 15: Assisted editing
+
+Normalize generation, editing, inpainting, segmentation, restoration, and
+upscaling behind capability-based endpoints. Keep model/provider names out of
+editor logic. Requests must exclude chat memory, show progress, cancel safely,
+and return named reversible layers with provenance. Manual tools remain fully
+usable without an endpoint.
+
+Much of the endpoint plumbing already exists; the remaining work is consistent
+capability discovery, lifecycle safety, and editor-native result handling.
+
+## Phase 16: Release gate
+
+Run complete user journeys on Chromium and Firefox desktop plus representative
+phone/tablet viewports. Add keyboard-only and accessibility coverage, mixed
+20-edit persistence/export tests, failure recovery, and large-document stress
+tests. No supported operation may silently flatten or discard retained state.
+
+## Architecture debt to control
+
+- `galleryEditor.js` is still a large orchestrator. Continue extracting domain
+  modules as visible features move, without a broad rewrite.
+- Legacy raster adjustment sublayers and first-class adjustment layers overlap.
+  Converge on the first-class model.
+- Pixel effects still rely heavily on synchronous full-canvas work.
+- `static/style.css` carries substantial editor-specific surface area and needs
+  clearer component boundaries before workspace customization expands.
+- The repository worktree contains many unrelated changes. Editor release and
+  merge decisions require a scoped diff or clean integration branch.
+
+## Recommended execution order
+
+1. Close and deploy Phase 10.
+2. Build Phase 11 through a cancellable render boundary.
+3. Consolidate the workspace in Phase 12.
+4. Define color/metadata policy and complete Phase 13.
+5. Finish worker rendering, stress, and recovery in Phase 14.
+6. Normalize assisted editing in Phase 15.
+7. Run the cross-browser professional release gate in Phase 16.
+
+Do not expand into full PSD fidelity, CMYK production, RAW development, 3D, or
+complete Photoshop parity before this critical path passes. Those are separate
+product decisions, not prerequisites for a strong Odysseus editor.