Photoshop's remaining blend modes in its groups (12.7a); v1.2.2 kernels for 12.7b

AGENTS.md

@@ -121,14 +121,15 @@ Platform adaptations, each forced by a missing Qt analog:
 - Outer Glow and brush Smoothing (12.5b, Swift 1.2.0): `OuterGlowEffect` joins the effects with Swift's defaults (20 pixels, white, 75%) and bounds (0–500, 0–1), `LayerEffectKind::outerGlow` ("Outer Glow") last, so the footer's menu, the list's rows and every helper take it; the manifest's `outerGlow` is Swift's `Codable` (`size`, `opacity`, the colour, `enabled` only while set). `LayerEffectsKernel` blurs the shape's coverage at sigma size ÷ 2, Metal's glow buffer (a size under 0.02 copies it, as Swift's zero shift does), and composes it over the drop shadow and under an outside stroke, clamped to glow × (1 − shape) × opacity; the renderer's margin takes three sizes, the stroke surface's reach three sizes and two. Swift's CPU `outerGlowCoverage` serves machines without Metal and is dead here, as the other CPU coverages are (9.6b), so Swift's CPU and Metal parity test has no twin. The preview cache keeps the last preview while one effect is hidden or shown on the same pixels (Swift's `dbe82b0`). A fix beyond Swift: a reduced preview scales the glow's size, as it scales the inner shadow's lengths (9.6c). The sheet shows the glow's swatch, Size (0–100 on the slider, 500 typed, px) and Opacity. Smoothing is Swift's string: `BrushSettings::smoothing` (0–100); while the Brush paints (either mode) with smoothing, the brush (`m_brushAnchor`) moves only once the pointer (`m_brushPointer`) pulls further than smoothing ÷ the viewport's zoom, and then by the excess along the string; the release paints on to the pointer; a cancel drops both. The other brush tools follow the pointer. Equivalent mutants: the press's pointer and the cancel's two resets (each makes the others' work redundant), `>` at the string's exact length (a move of zero), the release's tool and smoothing terms (otherwise it appends the last point again), and the surface's glow reach between the blur's three sigmas and Swift's three sizes. `BrushControls` shows Smoothing for the Brush alone: a 100-point slider in tenths and a 42-point `SelectionAmountField` of 0–100 with Swift's help. The rest of 1.2.0 is held already (TASKS.md 12.0, each note now saying Swift agrees) or not code (`NativeLayerList.moveLayer` has no caller; the spelling touches shader comments), but for two follow-ups of `90ee29f` and `7c4512a`: Select All never rests and reaches a focused layer list (7.1's note), and the invert test holds no wall clock. Tests: `OuterGlowTests` (Swift's, but the parity test), the glow in `LayerEffectsKernelTests`' shader replay, `LayerEffectsSurfaceTests`' rows and `EffectsPreviewCacheTests`' scaling, the kinds, manifest and menu in their files; `BrushSmoothingTests` and the bar in `BrushControlsTests`.
 - Camera RAW (12.6a, Swift 1.2.1): Core Image's RAW filter has no Linux twin, so `IO/RawImporter` develops through LibRaw (the user's decision), its thread-safe `libraw_r` found by pkg-config; `Dockerfile.dev` installs `libraw-dev`, the PKGBUILD and the flake depend on `libraw`, the distro images carry it. A RAW is any file whose extension names a type inheriting `image/x-dcraw` in the MIME database (`matches`, `isRawType` for a dropped picture, `globs` for the importer's filter), Swift's `UTType.rawImage`. `RawDevelopSettings` keeps Swift's fields, `isAsShot` and `reset`; `RawDevelopRequest` is Swift's tuple. White balance: `planckian` is Kim et al.'s cubic (1667–25000 K), `whitePoint` moves off the locus along its greener uv normal by tint ÷ 3000, `temperatureOf` inverts it by a mired search and golden sections: Adobe's scale and sign (the DNG SDK's `kTintScale`), so a positive tint is a greener white and turns the picture magenta, and D65 reads about +10, as Lightroom's Daylight. Known difference: CIRAWFilter's temperature and tint follow Apple's own model; these follow Adobe's convention on CIE 1960 uv. `asShot` reads the camera's multipliers (`cam_mul`, else dcraw's daylight `pre_mul`) and turns the neutral into xy through LibRaw's `rgb_cam` (a DNG's `cam_xyz` stays zero) with `pre_mul` put back; `develop` works back from the chosen white to camera multipliers (`user_mul`, the second green the first's), reading the camera's `pre_mul`, `rgb_cam` and size from unpack's copy (`rawdata`), since a process overwrites `color` with its own multipliers and a half-size one halves `sizes`; a white the matrix maps to a response at or below zero is refused, logged, where LibRaw would drop the balance in silence; the refusal is `ImageImportError(whiteBalance)`, a kind of Linux's own with words of its own, since `CIRAWFilter` takes every white and real cameras' matrices reach it inside the sliders (the warm and green corner). It takes LibRaw's 16-bit sRGB at a power of one (linear), with neither auto-brightening nor the maximum's adjustment (`adjust_maximum_thr` 0, so a frame near white keeps its level), clipped at white in camera space (`highlight` 0, so a clipped photosite stays neutral: unclipped, the matrix turns it magenta), where LibRaw divides by the smallest multiplier; the twin multiplies the smallest back, so the balance is anchored on green, as Core Image's, where dcraw alone brightens the frame as the temperature moves. Known difference: where a multiplier falls below green's (the slider's far ends), the frame's white falls to that multiplier. It makes the look itself, rows side by side: exposure multiplies linear light by 2^EV, clamped, then Boost mixes sRGB's curve (0) with LibRaw's BT.709 curve (1). Known difference: Apple's Boost curve is undisclosed; at 1 this is LibRaw's default curve. The result is opaque `RGBA8888_Premultiplied` tagged sRGB, oriented by LibRaw. Only three-colour sensors develop; a four-colour one is `unsupported` (dcraw's matrices hold no fourth to invert). A preview past its limit decodes at half size, then fits smoothly. `Queue` is Swift's actor: one develop at a time under a mutex, the unpacked frame kept for the previews of one file, a full develop always fresh, `release` letting go; Swift keys the cache by the limit too, since its filter's scale is fixed when made, where LibRaw halves per develop. LibRaw's refusals are `unreadable`, logged with its message on `omaphoto.io`; a surface that cannot be made is `ExportError(render)`. In the session (`EditorSession+Imports.cpp`) a RAW goes before the Photoshop check: `pixelSize` (unreadable when it fails) and Swift's budget (`tooLarge` past 30,000 a side or the pixels left), then `developRaw` shows the sheet with the camera's settings (the defaults when they cannot be read) and keeps the answer, `finishRawDevelop` clears the request, releases the queue on a worker and answers from the event loop (a resumed task): nothing skips the file, settings develop the whole frame on the import's worker, which catches `ImageImportError` and `ExportError`, into a layer named for the file. `rawDevelop` alone stands for Swift's `rawDevelop` and `showsRawDevelop`, which are set and cleared together; the latter's `didSet` is dead (the sheet shows only while importing, which holds file requests anyway), and so is the test hook `confirmRawDevelop`. `UI/RawDevelopSheet` is Swift's sheet in a window-modal `QDialog` (`rawDevelopSheet`) that `ContentView` shows while the request stands, its close button and Escape cancelling and a sheet the session takes away answering nothing: the title at 17 pixels bold, the 560 by 340 preview on 35% black rounded 6 with a spinner while a develop runs, four rows (a 90-point title as the buddy of a 300-point slider, the value 80 points wide in `PlaceholderText`: Exposure in hundredths, Temperature and Tint whole, Boost in thousandths, printed as Swift's `%.Nf`), Reset (resting while as shot), Cancel and the default Line truncated
 - Middle-button pan, tool defaults, Auto Select and the icon (12.6b, Swift 1.2.1): `Document/ToolDefaults` twins Swift's enum as a namespace: `boolean` (Swift's `bool`, a C++ keyword) and `set` keep Auto Select, the transform controls, the pixel grid, the layout grid, guides, rulers, Snap, the four Snap To switches and Lock Guides in `QSettings` under Swift's `tool.` keys, read by the session's members as they are made and written by each setter, and by the two places that show guides by themselves (`beginGuideCreation`, `addGuide`), as Swift's `didSet` sees those writes. Swift returns the defaults under XCTest; Qt has no such flag, and most test binaries run outside `QStandardPaths`' test mode, so the twin keeps the defaults until `ToolDefaults::enable()`, which `main` calls first (not under test, as the theme's construction is not). The settings file keeps text, so a stored value reads as `true` or `false`; anything else is ignored with a warning on `omaphoto.app`, where Swift's `as? Bool` is silent. The canvas's middle button (Swift's `otherMouseDown` for button 2) pans from any tool while a document is open, on a drag point of its own (`m_middlePanPoint`), so a left drag under way goes on beside it: a move with both buttons pans, then gives the left its turn (so a Hand drag pans twice), and a right-button tip drag waits for the middle's release. Known difference: macOS sends one drag event a motion, so which button Swift's canvas follows then is AppKit's choice. The press hides the brush circle and shows the closed hand, which outranks every other cursor; the release puts the tool's cursor and circle back. Qt can lose a release: a move without the middle button ends the pan. Unlike Swift's `mouseDown`, the press takes no focus. `transformPressLayer` gains Swift's foreground rule: with Auto Select, a press inside the active layer's box goes to the layer under the pointer when that is painted above it (a background holding every press no longer hides the layer on top); `above` reads both layers through checked lookups, since the pointer's layer and the visible active one are both drawn, where Swift guards each index. Swift's `underPointer != active.id` is left out as dead (`above` refuses a layer against itself); equivalent mutant: `>=` in `above` (only the active layer equals itself, and `selectLayer` of the active layer changes nothing). The reshaped app icon (`45ab8fd`) replaces `packaging/icons`. Tests: `ToolDefaultsTests` (the defaults until enabled, every toggle across sessions and as text, guides shown by a guide, a strange value), `theMiddleButtonPansFromAnyTool` in `CanvasNavigationTests`, Swift's `autoSelectPicksForegroundLayerStackedOnSelectedBackground` and a mask box past its layer in `TransformPressTests`, whose older Auto Select test now expects the layer above.
+- Photoshop's blend modes (12.7a, Swift 1.2.2): `LayerBlendMode` takes Swift's order, Photoshop's, and `allLayerBlendModes` follows it, so the blend keys step Normal, Darken, Multiply…; the raw values are Swift's (`Linear Dodge (Add)` among them), so the manifest reads them without a new version, as Swift's. `blendGroup` stands for Swift's static `groups`: each group's modes sit together in the enum, so the group is the last first member a mode reaches. `BlendModePicker` draws a separator between groups, as Swift's pop-up does; QComboBox's keys step over them and never make one current, so no preview names one. Hard Light and Exclusion are QPainter's composition modes; the other eight go by hand (`SeparableBlend`, `HslBlend`). The PSD reader takes Swift's new keys (`lbrn`, `lddg`, `hLit`, `vLit`, `lLit`, `pLit`, `hMix`, `smud`, `fsub`, `fdiv`); Dissolve, Darker Color and Lighter Color fall to Normal with the conversion note, and Swift's renamed test uses Dissolve. A fix beyond Swift: Swift's `LiveMaskRenderer` composites a clipping stack's group and an adjustment's result through `cgMode`, which is Normal for the eight (v1.2.2's `prepareStacks`, `drawComposite` and `adjust`, unchanged through 1.3.3), so a base or an adjustment in one of them draws as Normal there; the twin hands every mode to `LayerRenderer::composite`, which blends the eight by hand, as Photoshop composites a clipping group with its base's mode (`ClippingStackTests::aStackBlendsOnceWithItsBasesMode`, `AdjustmentLayerTests::adjustmentBlendAndSoftMaskPreserveCoverage`). Swift's `coreImageFilter` has no twin: `needsSurface` names the modes. Equivalent mutants: `<=` against `<` at one half in Vivid and Pin Light (both branches give the backdrop there). Tests: the formulas in `BlendModeTests`, the menu's groups and keys in `BlendModePickerTests`, the order in `LayerAppearanceTests`, `BlendShortcutTests`, `EditorCanvasTests` and `ProjectManifestTests`, the keys in `PSDRoundTripTests` and `PSDImportTests`, the canvas against the export in `CanvasDisplayTests::photoshopsOwnModesShowAsTheExportDoes`.
 - Drops between projects: `ProjectWorkspace::draggedLayerSource` finds the tab whose document holds the dragged id (Swift reads the drag pasteboard; the twin reads the drag's `QMimeData`, which every drop target has), `canReceiveDrag(data, destination)` refuses only a layer's own tab, and `receiveProviders` copies several ids one after another, as Swift awaits each provider, so a two-row drop on the New button opens two tabs as Swift's does. `ContentView` takes such a drop over its whole area (`setWorkspace` hands it the workspace; `acceptsDrop` keeps Swift's guards: busy, the sheet, the importer, a rename; `levels` arrives with 9.x), shows the 3-point accent ring inside the canvas while targeted and hands the drop's document point on when it fell on the canvas. `ProjectTabButton` takes drops for its tab (accent fill and rim, "Add to <title>"), and `NewCanvasButton`, the toolbar's New canvas button with the action as its default, for a fresh tab ("Open in a new project tab"), both refusing an Alt drag, which duplicates in the panel; Swift's transient `NewTabDropSlot` in the strip has no twin, the New canvas button is `NewProjectDropTarget` already. Files and pictures arrived with 10.4.
 - `CanvasThumbnail` draws a layer or a mask inside the canvas's box at `backingScale` 2 (the panel's pixmaps carry that ratio); a mask's ground is the mean of its edge pixels, as Swift's `edgeTone`. `LayerIcons` draws the panel's SF Symbols as paths, in one palette colour, like `ToolIcons`. `BlendModePicker` is a `QComboBox` whose popup previews the highlighted mode through `previewBlendMode` for the layer it opened on (Qt calls `hidePopup` before `activated`, so the preview, the target and the highlight are cleared from the event loop, after a choice had its chance) and refuses a choice once another layer is active. `LayerAppearanceControls` is Swift's blend and opacity row: the slider's press and release are one opacity drag (the release is watched application-wide while the slider is down, so a popup opened mid-drag cannot keep the step open), the percent field applies once through its `FocusOut`, which Return and Escape cause (Swift's `releasesFocusOnCommit`), and steps with Up and Down (Swift's `isFinite` test and the steps' clamp are left out: `setLayerOpacity` refuses a value that is no finite number and clamps the rest), and another active layer makes the controls anew, as Swift's `.id` does.
 - `ProjectWorkspaceView` is the `QMainWindow`: the front tab's `ContentView` as its central widget, made anew when another tab comes to the front, as SwiftUI's `.id` rebuilds it, and disabled while the workspace manages; the window holds the shown tab (`std::shared_ptr`) until the old editor is deleted, as Swift's views hold their session, so a replaced or closed tab's session never ends under its editor (`ProjectWorkspace::tab` is public for this); a `QToolBar` with the New canvas action, the `ProjectTabStrip`, a spacer and the four zoom actions, since SwiftUI's `.toolbar` modifier lives in `ContentView` but the toolbar belongs to the window. Its actions follow the front session's `changed()`, and on that signal the window syncs every tab's button as well, because a busy front tab dims the other tabs' buttons, which their own sessions' signals do not reach; the strip syncs its buttons on the workspace's signal, each button on its own session's. The window's title is the front tab's, with Qt's `[*]` placeholder, so `setWindowModified` can show the mark that `isDocumentEdited` shows; `setWindowFilePath` carries `representedURL`. The editor's own minimum size is cleared inside the window, which owns the 800 × 520 minimum for the whole, toolbar included. Closing the window ignores the event and asks the workspace (`closeWindow`), which confirms tab by tab and then closes the window again with the property `closeConfirmed` set, since the workspace may not include `UI/` headers; a confirmed close is accepted and the mark cleared, so a window shown again asks again. `ProjectTabStrip` is a `QScrollArea` whose buttons are kept for the tabs that stay, moved for the tabs that moved, made for new tabs and deleted for tabs that went; its row is sized to its tabs by hand (a resizable scroll area would squeeze every title below Swift's 35 points) and resized again whenever a title changes, and the front tab scrolls into view at once; it and its viewport fill no background, so the toolbar shows through as Swift's mask lets it (a stylesheet would do the same but freezes the widgets' palette, so a theme switch would pass them by); the unsaved dot is a character before the title. Files named on the command line go to `ProjectWorkspace::receive`, as Finder's Open With reaches the delegate. Layer drops on tabs and the New canvas button are 4.7's; file and picture drops arrived with 10.4.
 - `CompositorMenus` builds the window's `QMenuBar` from Swift's `.commands`, entry for entry, as far as the session functions exist (`TASKS.md`, "Menu items owed", lists the rest); ⌘ is Ctrl and ⌥ is Alt in every shortcut. Its entries follow the front tab's session, like the toolbar. Swift's Undo and Redo keep a text field's own undo while one has focus, so the twin's do the same: with a `QLineEdit` in focus the entries are the field's, titled bare and always enabled; otherwise they carry the step's name, and only while the session's history is usable. Focus is state the session does not announce, so the menus also sync on `QApplication::focusChanged`. Keyboard navigation (Alt+E) hands focus to the menu bar itself, so the menus keep the field that held it until focus lands anywhere else. The View menu's Pixel Grid entry is checkable and follows `showsPixelGrid`. `Close Project` closes the tab (Swift's `close(window)` hands over to the workspace); `Delete Layer` is Swift's `deleteLayerOrMask`, which takes a chosen effect first since 9.6a; since 9.6d its title names that effect (`Delete Stroke`). The `Hide` entries and `Check for Updates` have no twin (the desktop hides windows; distro packages update).
 - The session's gates (`canEditLayers`, `canUseHistory`) and its `selectLayer`, `selectTool`, `undo` and `restore` read only the state that exists so far. `TASKS.md` lists, under "Session hooks owed", the term each later item adds. `reorderLayers` takes a `std::set<int>` for `IndexSet` and reproduces SwiftUI's `move(fromOffsets:toOffset:)`.
 - `LayerMask::clipImage` returns nil when the placed grid cannot be rendered, as Swift's `try?` does, and logs a warning on `omaphoto.rendering` so the loss is visible.
-- `SeparableBlend` has no twin. It exists because CoreGraphics gets Color Dodge and Color Burn wrong, and since 1.2.0 (`121a15f`) it blends them in sRGB, as QPainter does; QPainter's follow the PDF formulas (`BlendModeTests::everyBlendModeMatchesThePdfFormulas` proves all fourteen modes within 2/255).
-- `Rendering/HslBlend` is Linux-only: Hue, Saturation, Color and Luminosity, which QPainter lacks, blended by hand over a copy of the backdrop.
+- `Rendering/SeparableBlend` twins Swift's file for the modes QPainter lacks since 1.2.2: `needsSurface` names Linear Burn, Linear Dodge (Add), Vivid Light, Linear Light, Pin Light, Hard Mix, Subtract and Divide, and `channel` is Photoshop's formula for each on one channel (in Vivid Light a zero divisor is infinity, clamped to the end; Divide by black is white, zero over zero included, a choice of the twin's, since neither Photoshop nor Core Image publishes it). Swift reaches Core Image's filters, in sRGB as Color Burn and Dodge have been since 1.2.0 (`121a15f`); Color Burn and Dodge themselves stay QPainter's, which follow the PDF formulas, as do its Hard Light and Exclusion (`BlendModeTests::everyBlendModeMatchesThePdfFormulas` holds all twenty-four modes within 2/255 against formulas written apart). Known difference: Core Image's code is not published, so its edges (Hard Mix exactly at one, a divisor of zero) follow Photoshop's definitions, not measured Core Image. Hard Mix is Photoshop's at full fill, white where backdrop and source reach one together.
+- `Rendering/HslBlend` is Linux-only: the modes QPainter lacks (Hue, Saturation, Color and Luminosity, and since 1.2.2 `SeparableBlend`'s eight), blended by hand over a copy of the backdrop with the PDF's compositing, so every path that hands a mode to `HslBlend::handles` (the export, the canvas's surface, live masks, effects) takes the new ones.
 - Known difference: CoreGraphics enlarges "High quality" layers with a sharper kernel; QPainter offers bilinear only, so `InterpolationQuality::high` and `low` draw alike when enlarging. Reductions are sharp on both (halvings).
 - Where an Apple framework threads internally (vImage, Core Image, Metal), the twin threads with QtConcurrent.
 - A Swift error enum becomes an exception class with a `Kind` enum; `what()` carries the Swift `errorDescription`.