UDreamThrobber

A throbber whose hierarchy is code, not an asset: N pieces that pulse, saying only "something is

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Declared in Public/Controls/DreamThrobber.h.

A throbber whose hierarchy is code, not an asset: N pieces that pulse, saying only "something is happening".

ONE CONTROL FOR UMG'S TWO, which is the call this library has already made three times: the progress bar has Bar and Radial rather than two classes, the slider has a Direction rather than two Blueprint presets, the scroll box has an Orientation. The pieces, the period, the colours and the fade are identical between a Throbber and a CircularThrobber; the only thing that differs is where the pieces are put, so that is one enum and not one class. The palette still offers both rows -- they differ by a single property write, exactly like the two sliders.

WHY IT TICKS, WHEN NOTHING ELSE IN THE LIBRARY DOES

Every other animated thing here is a TWEEN: it has a start, an end and a duration, and the tween manager owns the clock. A throbber has none of those -- it runs until somebody takes it off screen -- so a tween would have to be re-started forever, and a looping tween per piece would be N objects the manager walks every frame to do arithmetic this control can do in one pass. So it opts into NativeOnTick (off by default for every widget, see UDreamUserWidget::SetWantsTick) and writes the opacities itself.

That also makes it correct where the tween manager does not exist: the manager is a world subsystem and hands back null in a headless test and in the designer's preview, where a tween-based throbber would simply stand still. This one animates wherever something calls its tick, and holds its first frame where nothing does -- which is a throbber that LOOKS like a throbber in the designer rather than an empty box.

NO PLAY / STOP, for UMG's reason: a throbber is not a timeline. Take it off screen to stop it.

Properties

Name	Type	Category	In the details panel	From Blueprint	Description
`Style`	`FDreamThrobberStyle`	Throbber	yes	`GetStyle` / `SetStyle`	This instance's own look. The project sheet wins while StyleSource says so AND a sheet actually exists; with no sheet in the project this IS the look in effect.
`Shape`	`EDreamThrobberShape`	Throbber	yes	`GetShape` / `SetShape`	A row of pieces, or pieces around a circle. UMG's Throbber and CircularThrobber.
`bAnimate`	`bool`	Throbber	yes	`GetAnimate` / `SetAnimate`	Off holds the pieces at the phase they were on. The widget stops ticking with it.
`bAnimateHorizontally`	`bool`	Throbber	yes	`GetAnimateHorizontally` / `SetAnimateHorizontally`	Whether a piece also PULSES on that axis -- UMG's bAnimateHorizontally / bAnimateVertically, and Slate's rule for them: the piece is scaled on the ticked axis by the same wave that drives its opacity, so it swells as it brightens and shrinks as it fades.
`bAnimateVertically`	`bool`	Throbber	yes	`GetAnimateVertically` / `SetAnimateVertically`
`PieceRootNode`	`TObjectPtr<UDreamWidget>`	Throbber	-	read only	What the pieces hang under, and the control's one built-in node.
`PieceNodes`	`TArray<TObjectPtr<UDreamWidget> >`	Throbber	-	read only	The pieces, in order. Public because a decorator may want to skin one.

Functions

Function	Kind	Description
`bool GetAnimate()`	pure	Get Animate
`bool GetAnimateHorizontally()`	pure	Get Animate Horizontally
`bool GetAnimateOpacity()`	pure	Whether the pieces fade at all -- UMG's bAnimateOpacity, read off how faint they are allowed to get: a floor of 1 keeps every piece solid, which is the flag being off.
`bool GetAnimateVertically()`	pure	Get Animate Vertically
`int32 GetNumberOfPieces()`	pure	The four numbers UMG's two throbbers offer one at a time.
`float GetPeriod()`	pure	Get Period
`float GetPhase()`	pure	How far through one cycle the animation is, 0 to 1. Authored in; readable out.
`float GetRadius()`	pure	Get Radius
`EDreamThrobberShape GetShape()`	pure	Get Shape
`FDreamThrobberStyle GetStyle()`	pure	Get Style
`void SetAnimate(bool bInAnimate)`	callable	Set Animate
`void SetAnimateHorizontally(bool bInAnimateHorizontally)`	callable	Turning it OFF re-places every piece at once, because a piece frozen mid-pulse would otherwise keep the width the last tick gave it -- a switch that leaves the thing it switched off in a random state is a switch that looks broken.
`void SetAnimateOpacity(bool bInAnimateOpacity)`	callable	Off pins the floor at 1. On restores the style's shipped floor, but only when the floor is currently 1 -- so switching off and on again is not a way to lose a hand-tuned value, and a throbber already fading keeps fading exactly as far as it did.
`void SetAnimateVertically(bool bInAnimateVertically)`	callable	Set Animate Vertically
`void SetNumberOfPieces(int32 InNumberOfPieces)`	callable	Rebuilds the piece pool, which is what a count IS here.
`void SetPeriod(float InPeriod)`	callable	Seconds for one full cycle. Drives the linear shape too, where UMG offers it only on the ring.
`void SetRadius(float InRadius)`	callable	How far out the pieces ride. Circular only, as in UMG; the linear shape ignores it.
`void SetShape(EDreamThrobberShape InShape)`	callable	Re-places every piece: the two shapes put them in different places, nothing else differs.
`void SetStyle(FDreamThrobberStyle InStyle)`	callable	This instance's whole look, replaced and pushed -- which for a throbber means the piece POOL is rebuilt if the count changed. See UDreamButton::SetStyle for the caveat about the sheet.

Compared with UMG

Every Blueprint-facing member of the UMG class, and where it went. adopt: same name, same meaning. map: here under another name or on another type. reject: deliberately absent, with the reason.

UMG	Member	Status	Here	Note
`UCircularThrobber`	`NumberOfPieces`	map	`FDreamThrobberStyle::NumberOfPieces`	One control and one style for UMG's two throbbers; Shape = Circular is this class.
`UCircularThrobber`	`Period`	map	`FDreamThrobberStyle::Period`	Seconds for one full cycle, and it drives the linear shape too -- UMG only offers it on the circular one.
`UCircularThrobber`	`Radius`	map	`FDreamThrobberStyle::Radius`	How far out the pieces ride, measured from the middle. Circular only, as in UMG.
`UCircularThrobber`	`Image`	map	`FDreamThrobberStyle::PieceBrush`	See the Throbber table: a piece is a procedural rect, so the brush is its body texture.
`UCircularThrobber`	`SetNumberOfPieces`	adopt	`SetNumberOfPieces`	One control for UMG's two, so this is the same call the Throbber table lists.
`UCircularThrobber`	`SetPeriod`	adopt	`SetPeriod`	Drives the linear shape too, where UMG offers it only on the ring.
`UCircularThrobber`	`SetRadius`	adopt	`SetRadius`	Circular only, as in UMG; the linear shape ignores it.
`UCircularThrobber`	`bEnableRadius`	reject		The inline tick beside UMG's Radius, and Transient there: it exists so an unticked radius falls back to the Slate style's. A radius here is always the style's own number, so there is nothing for a tick to choose between.
`UThrobber`	`NumberOfPieces`	map	`FDreamThrobberStyle::NumberOfPieces`	In the style: how many dots a project's spinners have is a theme decision, and the control rebuilds its piece pool on every push.
`UThrobber`	`bAnimateHorizontally`	adopt	`bAnimateHorizontally`	Slate's rule, kept: the piece is SCALED on the ticked axis by the same wave that drives its opacity, so it swells as it brightens. One wave for both rather than a second clock. Off by default, which is what this throbber has always drawn.
`UThrobber`	`bAnimateVertically`	adopt	`bAnimateVertically`
`UThrobber`	`bAnimateOpacity`	map	`FDreamThrobberStyle::MinOpacity`	A float where UMG has a bool, and it says more: MinOpacity 1 is UMG's bAnimateOpacity off (every piece stays solid), and anything less is how faint a piece gets at the bottom of its cycle. GetAnimateOpacity / SetAnimateOpacity spell UMG's bool over it.
`UThrobber`	`Image`	map	`FDreamThrobberStyle::PieceBrush`	FDreamUIFaceBrush rather than FSlateBrush -- a piece is a procedural rect and the brush is its body texture. Empty is the plain rounded dot.
`UThrobber`	`SetNumberOfPieces`	adopt	`SetNumberOfPieces`	Rebuilds the piece pool, which is what a count IS here. Edits this instance's style; see UDreamBorder::SetPadding for the caveat about a project sheet.
`UThrobber`	`SetAnimateHorizontally`	adopt	`SetAnimateHorizontally`	Turning it off re-places every piece, so a piece frozen mid-pulse does not keep the width the last tick gave it.
`UThrobber`	`SetAnimateVertically`	adopt	`SetAnimateVertically`
`UThrobber`	`SetAnimateOpacity`	adopt	`SetAnimateOpacity`	Off pins the floor at 1; on restores the shipped floor only when the floor is currently 1, so switching off and on is not a way to lose a hand-tuned value.
`UThrobber`	`SetStyle`	adopt	`SetStyle`	UThrobber has no style struct; this is the family's spelling, and the one call that rebuilds the piece pool.

WHY IT TICKS, WHEN NOTHING ELSE IN THE LIBRARY DOES

Properties

Functions

Compared with UMG

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