Camera Raw panel's remaining groups and the Filter menu entry (12.8b2)

AGENTS.md

@@ -124,7 +124,8 @@ Platform adaptations, each forced by a missing Qt analog:
 - 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`.
 - Black & White, Color Balance and Invert (12.7b, Swift 1.2.2): `kernels/AdjustPixels.c/.h` are v1.2.2's, with `adjust_black_white` and `adjust_color_balance`, run through `ImageAdjustmentPixels::run` on one thread as Swift's. `BlackWhiteSettings` and `ColorBalanceSettings` keep Swift's fields, defaults and bounds (the `isFinite` terms left out, as the bounds refuse NaN and infinities); `apply` throws `ProjectError(invalid)` past them and Color Balance hands an untouched image back. Swift's `FilterSettings.normalized` does not clamp either, so a number typed past a slider's range fails the preview with that error and a commit sets `brushError` with no step, as in Swift: the filter's two workers catch `ProjectError` beside their other errors, where it would otherwise escape as `QUnhandledException` and abort. `FilterKind` gains both after Grain (`isImageAdjustment`), `AdjustmentKind` Invert, Black & White and Color Balance in Swift's order, with `isEditable` (all but Invert) and `filterKind`; `LayerAdjustment` gains the two optionals with Swift's computed getter and setter pairs, validity and `apply` (Invert through `PixelInvert::run`, whole image, colour only); the manifest's `blackWhiteSettings` and `colorBalanceSettings` are Swift's synthesized `Codable`, every key required, left out while absent. `addAdjustment` opens the editor for editable kinds alone: an Invert layer applies at once. The editors carry both settings through `beginAdjustmentEditing` and `editedAdjustment`. A fix beyond Swift: Swift's Edit Adjustment… stays enabled on an Invert layer, whose editor switch breaks after the original is kept and the transaction opened, so nothing ever closes them and the session stays refused; the twin's entry rests for a kind that is not editable, and the two switches throw a `logic_error` for Invert, which nothing reaches. As Swift's row, an Invert layer says "Adjustment · Double-click to edit", yet a double click on its glyph renames it (`m_editableAdjustment`, Swift's `isEditable` test). The Image menu lists Black & White… and Color Balance… before Exposure…, the Layer menu's New Adjustment Layer entries take an ellipsis when editable, and a menu doubles the ampersand of "Black & White" (a lone one is a mnemonic in Qt), in the kinds' entries and in Undo and Redo's step names alike; object names drop it (`blackWhite`, `newBlackWhiteAdjustment`). `LayerIcons` draws Swift's three new symbols as paths: `circle.righthalf.filled`, `circle.filled.pattern.diagonalline.rectangle` (a rounded frame, diagonal lines, a filled circle) and `scale.3d` (three axes with arrowheads). The filter sheet's two kinds live in `UI/FilterSheet+Adjustments.cpp` (the sheet's file neared 500 lines): the six families and Tint's Hue and Saturation, shown while Tint is on (Swift's `if`, the rows `m_shownWhen` holds with Advanced's), and Color Balance's three headlines (13 pixels, semibold, Swift's `.headline`, as the effects sheet's) over three rows each and Preserve Luminosity; each `flag` is Swift's `Toggle` with its help as the tooltip. `NativeLayerList` stops listening in its destructor, as `ContentView` does: closing a list window hides it first, and a rename's focus-out then commits into a list half destroyed. Tests: Swift's `invertAppliesWithoutAnEditor` in `AdjustmentLayerTests`, its editor test over the editable kinds in `AdjustmentEditorTests` and `FloatingPanelTests`, `ColorAdjustmentTests` (the kernels against Photoshop's defaults and a tint worked in HSL, the tones of Color Balance and Preserve Luminosity, bounds, every manifest key, the sheet), the kinds, keys and menus in `FilterModelTests`, `LayerAdjustmentTests`, `AdjustmentPanelTests`, `CompositorMenusTests` and `SelectMenuTests`. `ProjectExportFailureTests`' two panel limits rose from 2,048 KB: the thousand-layer snapshot grew by the two optionals of every record (2,560 KB since 12.8d).
 - The Camera Raw filter's model (12.8a, Swift 1.2.3): `kernels/AdjustPixels.c/.h` are v1.2.3's, with the Camera Raw kernels and Grain's particle size (`59b5040`); that kernel warns under `-Wunused-parameter` and `-Wmisleading-indentation` through 1.3.3 (both lines date from `9982fad`; `075a71b` fixes another), so CMake silences those two for that file alone. `Document/CameraRaw.h/.cpp`, `CameraRawColor`, `CameraRawDetailOptics` and `CameraRawGeometryCalibration` twin Swift's four files; Swift's `CameraRaw.swift` runs to 638 lines, so its session extension is `CameraRaw+Session.cpp` with `CameraRaw+Session.h`. The enums keep Swift's raw values and order; `CameraRawClipping` keeps Swift's bits (highlights 1, shadows 2); `Balance` and `Gains` are structs for Swift's tuples; `region` returns a reference where Swift writes through a key path. `CameraRawDrag` sits in `CameraRaw.h`, where Swift's sits in `CameraRawColor.swift`: it holds the whole settings, which C++ needs complete. Swift's panel state sits on `FilterEdit` (the shown groups, pages, swatch, point index, the tools, the guide draft, clipping, sharpen mask, the scope and its mode, the readout); the twin gathers it in `CameraRawPanel`, `FilterEdit::rawPanel`, written through `setCameraRawPanel`, which notifies while an edit is open. `renderSettings` is Swift's settings with the hidden groups left out (`applying`); the commit renders and keeps those, so a hidden group stays out next time, and an identity grade closes as Cancel does. `previewJob` carries the panel's views; the preview's worker runs `CameraRawScope::preview`, whose scope lands on the panel. A fix beyond Swift: Swift's `preview` drops the point colour's view (it runs the job itself only for clipping or the sharpen mask, through 1.3.3), so Visualize never shows; the twin runs the job for it too. Geometry's warp is `QTransform::quadToQuad` from the image's rect to Swift's corners flipped to y down, drawn smooth and antialiased; a warp Qt cannot solve is a `logic_error`. Constrain Crop fits the frame inside `brush_alpha_bounds`; a crop whose copy finds no memory is `ExportError(render)`, where Swift's `cropping` returning nil falls back to the uncropped warp. Left out as dead: `apply`'s `isValid` guard and with it `isValid` (settings arrive normalized, and nothing else asks), `nudged`'s guard for an empty channel (`normalized` repairs every curve to two points; `at` throws if that breaks), the vectorscope's wrap of a negative hue (its angle's cosine and sine turn round alike), the parametric curve's `max(0, weight)` (a tone inside its region weighs 0 to 1), each group's `applying(shows:)` (no caller), and the defringe eyedropper's own `normalized` (`updateFilter` normalizes). Equivalent mutants: `tone < shadow` against `<=` (the regions meet with equal weight), the defringe tie's `<` against `<=`, the mixer's `weights > 0` against `>= 0` (a zero weight adds nothing), the identity commit's cancel (the history drops an unchanged step), and Auto's `committing` term (a committing edit refuses `updateFilter`, and the landing asks again). The Filter menu and the sheet leave Camera Raw out until its panel (12.8b). Tests: `CameraRawTests`, `CameraRawSessionTests` (Swift's session tests; the preview's views and scope), `CameraRawToolsTests`, `CameraRawRulesTests`, `CameraRawColorTests`, `CameraRawLensTests` (the kernel's calibration called directly), `CameraRawWiringTests` (Effects, Optics and Detail against their kernels called with the header's order, a clip view on an untouched grade, Auto in linear light, every eye's fields, Offset, Aspect and Constrain Crop against placed pictures, the scope's channels and hues, the curve, mixer and grading call with its floats written out, the sharpen-mask view, each lens flag alone, Grain's scale, a dull colour's reach, Rotate, Scale and Vertical against placed pictures), `CameraRawFixtures.h`, Grain's size in `ImageAdjustmentTests`, the kind in `FilterModelTests`.
-- The Camera Raw panel (12.8b1, Swift 1.2.3): Swift docks the filter's `NSPanel` to the document window's right edge, full height, following it (`dockedToMainWindowRight`). Wayland lets no client place a window, and a tiling compositor would tile a second one, so the twin docks inside the window: `FloatingPanel::show` takes a dock slot, `ContentView`'s `panelDock` at the right of the middle row, `FloatingPanel::dockedWidth` (Swift's 440) wide, and there the panel is its own `PanelWindow` made a plain child (`Qt::Widget`), so `QDialog` still takes Escape as Cancel and Return as the default button; a header holds the title and a close button, which cancels. A docked frame is never remembered (`moveEvent` asks `isWindow`), so Gaussian Blur and the rest reopen where they were left, Swift's `dockedPlacementLeavesTheSavedFilterPosition`; `refocus` hands a docked panel the keys through `setFocus`, looking past the hidden floating panel of the same name, which is the window's child too. The dock takes room beside the layers panel and spans the middle row alone, so the tool bar and status bar keep their width, where Swift's panel lies over the window's whole height (known difference). Refocus hands the keys to the docked panel itself, not the field last typed in (known difference: `makeKey` keeps its first responder). `UI/CameraRawSlider` twins Swift's file: `CameraRawSliderTrack` with Swift's colours, the gradient drawn 4 points high across the groove under the style's knob, a double click on the knob (its rect two points out) resetting; a press on the track is `SliderSnap`'s (10.5): Swift's 0.18 s glide has no twin, and a drag goes on from the snapped knob, as every slider of the twin does (known differences); `display` keeps a knob under a drag, Swift's `isTrackingValue`; the track is fixed at construction, and Swift's track update in `updateNSView` arrives with its first changing caller, the mixer's families (12.8b2). `UI/CameraRawControls.h/.cpp` and `CameraRawControls+Basic.cpp` (Light, Color, Effects) twin Swift's view: the scope 110 high on black at 35%, the three ribbons at 55% in SwiftUI's dark red, green and blue (the Levels histogram's values) or the vectorscope's cells, square by the width and counted up from the bottom, so a 110-point graph shows its lowest 18 rows, as Swift's does, its context menu choosing the mode, the two clipping triangles lit in that blue and red, the readout; the words say Alt for Option and a right click for Control-click; the ten groups, Light and Color open, each eye shown while its group adjusts; a row's title (96 points at least, a double click resetting), `CameraRawSlider` and a 56-point `PickerField` showing Swift's `.number` to the row's decimals. A row's object name is its settings field (`vignetteAmountSlider`), since titles repeat. Alt is read from `QGuiApplication::keyboardModifiers`, Swift's `NSEvent.modifierFlags`, and its release (auto-repeat aside), from any window, ends the clipping and sharpen-mask views (Swift's local monitor). Curve to Calibration fill their groups in 12.8b2, and the Filter menu's entry waits for them. On the canvas (`EditorCanvas+CameraRaw.cpp`) a hover reads the readout (Swift's `mouseMoved`, never a drag), leaving clears it, the three eyedroppers sample and hand the panel the keys, the guide and the targeted drag begin, go on and end on release, and a move without the left button ends either, since Qt can lose a release; the four tools are `picking`, so the eyedropper shows. `EyedropperIcon::icon` came from `LevelsSheet`, which shares it. Left out as dead: the canvas's `kind == cameraRaw` and edit terms before the readout (the session asks), a hide of the other placement's panel in `show` (every edit closes its panel first), Swift's clipping reset before a row's reset (`assign` clears it), and the docked panel's own hide on close (its slot hides it). Equivalent mutants: the titles' minimum width, 96 points (a layout sizes labels offscreen alike), and the unlit triangle's 55% white (cosmetic, over whatever the scope shows). Two consequences of the named differences: a double click on a slider's track resets it, since the first press puts the knob under the second; and a canvas press takes the keys, so a field still being typed in commits at the click, where Swift's panel keeps its field editor. Tests: `CameraRawSliderTests` (Swift's three), `CameraRawPanelTests`, `CameraRawCanvasTests` (the dock in a real window among them), `FloatingPanelTests::dockedPlacementLeavesTheSavedFilterPosition`.
+- The Camera Raw panel (12.8b1, Swift 1.2.3): Swift docks the filter's `NSPanel` to the document window's right edge, full height, following it (`dockedToMainWindowRight`). Wayland lets no client place a window, and a tiling compositor would tile a second one, so the twin docks inside the window: `FloatingPanel::show` takes a dock slot, `ContentView`'s `panelDock` at the right of the middle row, `FloatingPanel::dockedWidth` (Swift's 440) wide, and there the panel is its own `PanelWindow` made a plain child (`Qt::Widget`), so `QDialog` still takes Escape as Cancel and Return as the default button; a header holds the title and a close button, which cancels. A docked frame is never remembered (`moveEvent` asks `isWindow`), so Gaussian Blur and the rest reopen where they were left, Swift's `dockedPlacementLeavesTheSavedFilterPosition`; `refocus` hands a docked panel the keys through `setFocus`, looking past the hidden floating panel of the same name, which is the window's child too. The dock takes room beside the layers panel and spans the middle row alone, so the tool bar and status bar keep their width, where Swift's panel lies over the window's whole height (known difference). Refocus hands the keys to the docked panel itself, not the field last typed in (known difference: `makeKey` keeps its first responder). `UI/CameraRawSlider` twins Swift's file: `CameraRawSliderTrack` with Swift's colours, the gradient drawn 4 points high across the groove under the style's knob, a double click on the knob (its rect two points out) resetting; a press on the track is `SliderSnap`'s (10.5): Swift's 0.18 s glide has no twin, and a drag goes on from the snapped knob, as every slider of the twin does (known differences); `display` keeps a knob under a drag, Swift's `isTrackingValue`; the track is fixed at construction: Swift's track update in `updateNSView` has no twin, since the rows whose tracks change (12.8b2's mixer) are made anew. `UI/CameraRawControls.h/.cpp` and `CameraRawControls+Basic.cpp` (Light, Color, Effects) twin Swift's view: the scope 110 high on black at 35%, the three ribbons at 55% in SwiftUI's dark red, green and blue (the Levels histogram's values) or the vectorscope's cells, square by the width and counted up from the bottom, so a 110-point graph shows its lowest 18 rows, as Swift's does, its context menu choosing the mode, the two clipping triangles lit in that blue and red, the readout; the words say Alt for Option and a right click for Control-click; the ten groups, Light and Color open, each eye shown while its group adjusts; a row's title (96 points at least, a double click resetting), `CameraRawSlider` and a 56-point `PickerField` showing Swift's `.number` to the row's decimals. A row's object name is its settings field (`vignetteAmountSlider`), since titles repeat. Alt is read from `QGuiApplication::keyboardModifiers`, Swift's `NSEvent.modifierFlags`, and its release (auto-repeat aside), from any window, ends the clipping and sharpen-mask views (Swift's local monitor). Curve to Calibration fill their groups in 12.8b2, and the Filter menu's entry waits for them. On the canvas (`EditorCanvas+CameraRaw.cpp`) a hover reads the readout (Swift's `mouseMoved`, never a drag), leaving clears it, the three eyedroppers sample and hand the panel the keys, the guide and the targeted drag begin, go on and end on release, and a move without the left button ends either, since Qt can lose a release; the four tools are `picking`, so the eyedropper shows. `EyedropperIcon::icon` came from `LevelsSheet`, which shares it. Left out as dead: the canvas's `kind == cameraRaw` and edit terms before the readout (the session asks), a hide of the other placement's panel in `show` (every edit closes its panel first), Swift's clipping reset before a row's reset (`assign` clears it), and the docked panel's own hide on close (its slot hides it). Equivalent mutants: the titles' minimum width, 96 points (a layout sizes labels offscreen alike), and the unlit triangle's 55% white (cosmetic, over whatever the scope shows). Two consequences of the named differences: a double click on a slider's track resets it, since the first press puts the knob under the second; and a canvas press takes the keys, so a field still being typed in commits at the click, where Swift's panel keeps its field editor. Tests: `CameraRawSliderTests` (Swift's three), `CameraRawPanelTests`, `CameraRawCanvasTests` (the dock in a real window among them), `FloatingPanelTests::dockedPlacementLeavesTheSavedFilterPosition`.
+- The Camera Raw panel's other groups (12.8b2, Swift 1.2.3): `UI/CameraRawColorControls.h/.cpp` (Curve), `+Mixer.cpp` and `+Grading.cpp`, `UI/CameraRawDetailOpticsControls` and `UI/CameraRawGeometryCalibrationControls` twin Swift's three files, each view a `QWidget` over the session, synchronized on `changed()`. `UI/CameraRawRow` is Linux-only: the row each Swift view builds for itself (`sharpenSlider`, `opticsSlider`, `geometrySlider`, `calibrationSlider`, the curve's and mixer's sliders, 12.8b1's `slider`): a title of at least or exactly a width, `CameraRawSlider`, a field or none, a double click on the title resetting where Swift's main groups do; each view rounds the slider's value as its Swift twin does (Detail to whole numbers, Optics when its range starts at zero, Geometry and Calibration always, the rest not). Swift's segmented pickers are `cameraRawSegments`, touching checkable buttons in an exclusive `QButtonGroup`. The curve graph: a still press and release adds a point, a drag past two points moves the nearest divider or inner point, a double click removes the nearest inner point within 0.04 and its trailing release adds nothing, so the net is Swift's: SwiftUI adds on each click, `repair` drops the second as a duplicate and the double tap removes one. The graph is `CameraRawCurveGraph`: a class defined in a `.cpp` outside an anonymous namespace is global, and the Curves sheet's `CurveGraph` would share its vtable across the link. The mixer's rows whose help or track follow its tab, swatch or chosen point are made anew when those change, as SwiftUI renders them anew; a picked colour's swatch is shown at once, since a layout shows late children only later. The grading wheel fills a `QConicalGradient`, which runs counterclockwise from the right as the hue does (1.2.9's `96edd5f`), takes presses and double clicks inside its circle alone (Swift's `contentShape`), and Swift's `theDockedPanelFitsTheGradingWheels` holds; its stops are 96edd5f's own, pure HSV hues every 30 degrees (v1.2.3's six SwiftUI system colours predate that fix). Detail's idle noise rows are disabled under a 45% `QGraphicsOpacityEffect`, Swift's `.opacity(0.45).disabled`. Targeted Adjustment and Draw Guides are checkable push buttons, checked while armed, where Swift tints them (known difference); their SF Symbols, `scope` and `line.diagonal`, are `LayerIcons` paths. The Filter menu lists Camera Raw Filter… after Lens Correction, as Swift's. Known differences: a mixer family's field still being typed in loses its typing when the tab changes (the row is made anew), where SwiftUI's field would commit into the new tab; Equivalent mutants: the wheel's saturation cap (`normalized` clamps it), the picked swatches made anew only when their count changes (it spares rebuilds; Qt guards a swatch deleted in its own click) and the page menu's size policy (layout). The point-colour eyedropper is flat like the other two, where Swift leaves it bordered (cosmetic). Cosmetic, Swift's values and unpinned: the swatches' 18 points, Detail's idle 45%, the hue ranges' inset (title width and 10), the rows' spacing of 10 and the 11-pixel subheadlines. Tests: `CameraRawRowTable.h` walked by `CameraRawGroupRowsTests` (every row against Swift's values), `CameraRawGroupDrawTests` (drawing, pages, gestures, the panel through `FilterSheet`), `CameraRawGroupWordsTests` (every text, captions, buddies, the pickers' states, the mixer's pages, the wheel's lower half and rim, the curve's line, repaint and selected point), `CameraRawCurveMixerTests`, `CameraRawGradingLensTests`, the menu's entries in `CompositorMenusTests`.
 - Hash containers on the render path (12.8e): Qt 6.4 declares `QHashPrivate::Data::findOrInsert` `noexcept` while it allocates, so a `QHash` or `QSet` insert that finds no memory calls `std::terminate`, past every catch (found by a backtrace of `ProjectExportFailureTests` under load: the JPEG worker's render aborted in `LiveMaskGraph::validate`). Code a worker runs under a catch that promises to survive memory running out uses `std::map` and `std::set`, whose inserts throw: `LiveMaskGraph::validate`, `FolderMaskClip::draw` and `LiveMaskRenderer`'s caches (and `LiveMaskBaker::bake` beside `validate`, though its workers catch `ExportError` alone, so a `bad_alloc` there still ends the app, by design), as `ImageExporter::render` already keyed its records. The UI thread's own `QHash`es stay: a failure there ends in Qt's event loop either way. `RenderStarvationTests` replaces `operator new` on its thread and fails each allocation of `validate`, `prepareStacks` and `FolderMaskClip::draw` in turn: each must throw `std::bad_alloc`; the three aborted with the old containers. Painting is left out of it: Qt's painter is not exception-safe, and a failure injected inside it can leave a lock held.
 - 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.