Radial gradients show a dashed extent ellipse: its handle across the bar
sets the aspect ratio, the ellipse elsewhere rotates it, and the dot inside
the centre ring drags the focal point (GradientGeom.focal) for an off-centre
radial. paint.setGradientGeom takes aspect (%) and focal ([x,y] | null), and
start/end may be left out; the focal point keeps its place in the ellipse as
the vector, aspect and object transform. It renders as a two-point radial,
exports and imports as SVG fx/fy and PDF two-point radial shadings, expands
to off-centre rings, and travels in gradient params and the native format.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Colours gain a CIE Lab model (`Color::Lab {l,a,b}`, serde tag `lab`), handled through the
CMS (display, separation, conversions, gamut), tints (toward paper white), keep_model, harmonies,
recolouring, blends, Info and the Color panel. Swatch Options gets a Lab mode
(`swatch.edit {mode: "lab"}` / `{color: {l,a,b}}`), and colour params accept `{l,a,b}`.
Swatches panel → Spot Colors… (`ui.spotColors`, dialog `spotColors`) runs `swatch.spotOptions
{useLab}` (Document.spot_use_lab, default on): Lab spot colours show and separate from their Lab
values, or art linked to them takes their working-CMYK equivalents, as one undo step. PDF export
writes Lab spot inks as Separation spaces with a Lab alternate (tint function from paper white),
or a DeviceCMYK one with CMYK equivalents.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Applying a gradient swatch records it as the gradient's swatch (the Swatches panel highlights
it and the Gradient panel's swatch menu marks it). A stop given a global or spot swatch (and a
tint) in paint.editGradient / a gradient paint's stops, dropped from the Swatches panel or
picked in the stop popover stays linked: editing the swatch recolours it, in art and in
gradient swatches, deleting it unlinks it. Spot stops separate on their plate, and a gradient
whose stops are all tints of one spot ink (or paper white) exports to PDF as a Separation
shading; gradients mixing models are written in one colour space (the PDF writer requires it;
mixed models used to abort the export).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Freeform gradients carry their own points (colour, opacity, spread) and lines
(Catmull-Rom curves through points), blended by inverse-distance weighting
from each disc of pure colour. paint.editGradient {kind: "freeform", mode?}
places 4+ points inside the shape, coloured along the stops (which follow the
points' colours). The renderer samples the field on a cached colour grid
drawn as an image paint clipped by the fill or stroke. Moves, transforms,
box rebases and warps move the points; old files load unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
