The picker marked every pass it drew, including the one it closed in, so
for one pass after closing the dialog Escape handler still stepped aside
and a quick second Escape did nothing. The mark is now set only while the
picker stays open and cleared in the pass it closes (OK, Cancel, Escape or
a click outside); the picker also consumes the Escape it handles.
Test: the_escape_after_the_picker_closes_cancels_the_editor presses Escape
to close the picker and again in the very next pass, with no settling
frames: the editor cancels. It fails on the previous marking.
The stop colour now uses widgets::srgb_color_button, the After Effects-style
picker every colour input opens (#638): hex field, HSB/RGB fields, OK and
Cancel, sRGB as the project stores colours. The stop keeps its alpha.
The dialog Escape handler only stepped aside for egui popups, and this
picker isn't one, so in a modal dialog Escape with the picker open closed
the dialog too. The picker now marks the pass it was open in
(color_picker::open_recently), and the handler leaves Escape to it: Escape
restores the colour the picker opened with and closes only the picker.
Tests: ui_gradient_editor clicks inside the picker's colour field over the
modal editor, types a hex code, closes the picker by clicking outside it
and saves the stop; a new test checks that Escape and the picker's Cancel
restore the stop's colour and keep the editor and its other edits. That
test fails without the Escape change. ui_color_hex still passes.
The Timeline's "Edit Gradient…" on a gradient property (Gradient Fill /
Gradient Stroke ▸ Colors, Gradient Overlay) only painted its label. It now
opens a Gradient Editor (prop.editGradient): opacity stops above a preview
bar and colour stops below. Click to add a stop (it takes that track's
own value there), drag or type a Location to move it, set its opacity or
colour (egui's colour picker), Delete removes it (never the last of a
track, never while typing). The tracks stay in order while editing and the
selection follows its stop.
The editor works on a draft. OK sets the property once with prop.set at
the composition time it opened, snapped to the frame, with
timeBase: "comp" (offset and stretched layers get the key where it was
opened): one undo step, and nothing at all when the draft is unchanged, so
OK adds no keyframe. Cancel and Escape change nothing; Escape with the
picker open closes only the picker. On an animated gradient only the
keyframe at that time changes; when its stop counts no longer match a
neighbouring keyframe's (gradients only blend with equal counts) the
editor says so. The draft is saved in the typed form, so one colour stop
and each stop's RGBA survive.
prop.editGradient checks its target is a gradient property before the UI
opens anything, so agents get an error for a wrong one. New Gradient
color_at / opacity_at sample one track each (sample() multiplies opacity
in, which would apply it twice to a new stop).
Tests: ui_gradient_value (fails on main: the value had no automation id),
ui_gradient_editor (11), gradient_editor and keyframe unit tests.
tylerjenningsw