Class StyleTransitionConfig

Namespace

Velvet

Assembly

Velvet.Docs.dll

CSS-transition-based animation configuration for V.Motion. Drives a USS class swap (enter-from → enter-to / exit-from → exit-to); DurationSec / Easing are applied as inline styles. Use the presets on StyleTransition, optionally tuned via With(float?, EasingMode?, EasingMode?, float?).

public sealed class StyleTransitionConfig

Inheritance

object

StyleTransitionConfig

Fields

None

Sentinel value indicating "no transition": V.Motion(transition: StyleTransitionConfig.None) requests immediate mount/unmount with no animation.

Properties

Damping

Spring damping (only meaningful when Type is Spring). Higher values settle with less oscillation. Framer Motion's default (10).

DelayChildrenSec

A fixed delay (seconds) added before any inheriting descendant's staggered delay — see StaggerChildrenSec for the full propagation contract. 0 (default) means no fixed delay.

DelaySec

Animation start delay (seconds). Applied as the inline CSS transition-delay style. Foundation for stagger (sequentially delayed animations). 0 means no delay (default). Negative values are ignored (transition-delay is not set; behaves as no delay). Note: currently a single delay shared between enter and exit. If a separate exit delay is needed, consider adding ExitDelaySec.

DurationSec

Animation duration (seconds). Applied as the inline transition-duration style. Ignored when Type is Spring: a spring's settle time is decided entirely by Stiffness / Damping / Mass, not a fixed duration.

Easing

Easing mode. Applied as the inline transition-timing-function style. Defaults to EaseOut (for enter). Presets in StyleTransition.cs configure enter/exit easing separately. Ignored when Type is Spring: the physics integration IS the curve.

ExitEasing

Easing mode for exit. When null, Easing is reused. The presets in StyleTransition.cs typically use EaseOut for enter and EaseIn for exit.

Mass

Spring mass (only meaningful when Type is Spring). Higher values feel heavier / slower to accelerate. Framer Motion's default (1).

PropertyOverrides

Optional per-property transition overrides layered on top of the top-level DurationSec / Easing / DelaySec (e.g. opacity tweening in 0.15s while scale takes 0.5s). When set, transition-property switches from the implicit "all" catch-all — used for a variant class swap, which carries no transition-* of its own — to EXACTLY these properties, in declaration order: overrides REPLACE transition-property: all rather than layering on top of it, matching CSS semantics where an explicit transition-property list transitions only what it names. Name every property that should animate. Currently wired only where a variant swap would otherwise set transition-property: all (a variant-driven enter, or an exit driven by a variants + exit label) — a preset transition's own USS-declared transition-property is untouched. Null (default) preserves today's behavior unchanged. Not read when Type is Spring: a spring drives every animated channel with the SAME Stiffness / Damping / Mass — there is no per-property override of the spring model itself (only Tween's per-property duration/easing/delay can be overridden this way).

StaggerChildrenSec

Delay interval (seconds) applied sequentially to each DESCENDANT Motion that inherits its active label from this Motion (it declares variants but no own animate — see Animate) when that ambient label changes: the i-th such inheriting descendant, visited in document order, is delayed an additional DelayChildrenSec + StaggerChildrenSec

• i on top of its OWN DelaySec. 0 (default) means no stagger (every inheriting descendant responds at the same time). Unlike AnimatePresence's own per-child enter/exit stagger (V.AnimatePresence(staggerSec:)), this orchestrates a PLAIN parent → child label propagation — no AnimatePresence boundary is required; toggling this Motion's animate prop is enough. A descendant with its OWN explicit animate opts out of both the label inheritance and this stagger — it is driven by its own render, not this propagation (matching Framer Motion, where an explicit animate override disconnects a component from its parent's variant propagation). The stagger index is transitive: an inheriting descendant with no stagger config of its own passes this orchestration through to ITS OWN inheriting children, who continue claiming from the SAME sequence.

Stiffness

Spring stiffness (only meaningful when Type is Spring). Higher values snap toward the target faster. Framer Motion's default (100).

Type

Selects the animation model: a USS transition-* class swap (Tween, the default) or a physics-integrated spring (Spring). See TransitionType for the full contract, including what a spring does and does not animate.

When

Sequences this Motion's own class swap against its inheriting descendants' swaps (see StaggerChildrenSec) when its active label changes. Defaults to Together.

Methods

With(float?, EasingMode?, EasingMode?, float?)

Builds a new StyleTransitionConfig that overrides duration / easing on top of the preset. Class-name definitions are copied; only the specified parameters are overridden.