UDreamUIWidgetGeometryLibrary

Coordinate conversions between a widget's own space, the viewport and the screen -- this

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Inherits from UBlueprintFunctionLibrary.

Declared in Public/DreamUIWidgetGeometryLibrary.h.

Coordinate conversions between a widget's own space, the viewport and the screen -- this framework's USlateBlueprintLibrary.

Everything returns bool and writes its answer through an out-parameter, where UMG's equivalents return the value directly. That is deliberate and it is about world-space UI: a panel welded to a machine in the level has no viewport position until a camera is pointed at it, and the honest answers are "here it is" and "nowhere", not a number computed in the wrong space. A caller that ignores the bool gets a zero, not a lie that looks like a position.

Functions

Function	Kind	Description
`bool AbsoluteToLocal(FDreamUIWidgetGeometry InGeometry, FVector2D InAbsoluteCoordinate, FVector2D& OutLocalCoordinate)`	pure	A viewport pixel position, in the widget's own space. Assumes the point lies in the widget's plane.
`bool AbsoluteToViewport(UObject* WorldContextObject, FVector2D InAbsoluteCoordinate, FVector2D& OutPixelPosition, FVector2D& OutViewportPosition)`	pure	Viewport pixels, as both pixels and DPI-scaled viewport coordinates. UMG's AbsoluteToViewport.
`bool GetAbsoluteSize(FDreamUIWidgetGeometry InGeometry, FVector2D& OutAbsoluteSize)`	pure	The widget's size in viewport pixels. False when the rect cannot be placed in the viewport.
`FVector2D GetLocalSize(FDreamUIWidgetGeometry InGeometry)`	pure	The widget's size in its own units. Zero for a geometry that names no widget.
`FVector2D GetLocalTopLeft(FDreamUIWidgetGeometry InGeometry)`	pure	The corner local coordinates are measured from, in the widget's own space.
`FDreamUIWidgetGeometry GetWidgetGeometry(UDreamWidget* InWidget)`	pure	Read a widget's geometry -- UMG's GetCachedGeometry, GetTickSpaceGeometry and GetPaintSpaceGeometry all at once.
`bool IsUnderLocation(FDreamUIWidgetGeometry InGeometry, FVector2D InAbsoluteCoordinate)`	pure	Is a viewport pixel position inside this widget's rect? UMG's IsUnderLocation.
`bool LocalToAbsolute(FDreamUIWidgetGeometry InGeometry, FVector2D InLocalCoordinate, FVector2D& OutAbsoluteCoordinate)`	pure	A point in the widget's own space, in viewport pixels.
`bool LocalToViewport(UObject* WorldContextObject, FDreamUIWidgetGeometry InGeometry, FVector2D InLocalCoordinate, FVector2D& OutPixelPosition, FVector2D& OutViewportPosition)`	pure	A point in the widget's own space, as both viewport pixels and DPI-scaled viewport coordinates -- UMG's LocalToViewport, which hands back both for the same reason.
`bool ScreenToViewport(UObject* WorldContextObject, FVector2D InScreenPosition, FVector2D& OutViewportPosition)`	pure	A screen position as DPI-scaled viewport coordinates. UMG's ScreenToViewport.
`bool ScreenToWidgetAbsolute(FVector2D InScreenPosition, FVector2D& OutAbsoluteCoordinate)`	pure	The same screen position in viewport pixels. Here the two are the same space, so this is identity.
`bool ScreenToWidgetLocal(FDreamUIWidgetGeometry InGeometry, FVector2D InScreenPosition, FVector2D& OutLocalCoordinate)`	pure	A screen position -- what a mouse position or a world-to-screen projection gives you -- in the widget's own space. UMG's ScreenToWidgetLocal.
`bool TransformScalarAbsoluteToLocal(FDreamUIWidgetGeometry InGeometry, float InAbsoluteScalar, float& OutLocalScalar)`	pure	Transform Scalar Absolute to Local
`bool TransformScalarLocalToAbsolute(FDreamUIWidgetGeometry InGeometry, float InLocalScalar, float& OutAbsoluteScalar)`	pure	A LENGTH converted between the two spaces, with no origin involved -- UMG's Scalar_LocalToAbsolute and friends.
`bool TransformVectorAbsoluteToLocal(FDreamUIWidgetGeometry InGeometry, FVector2D InAbsoluteVector, FVector2D& OutLocalVector)`	pure	Transform Vector Absolute to Local
`bool TransformVectorLocalToAbsolute(FDreamUIWidgetGeometry InGeometry, FVector2D InLocalVector, FVector2D& OutAbsoluteVector)`	pure	A DIRECTION and length, per axis. UMG's Vector_LocalToAbsolute.

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
`USlateBlueprintLibrary`	`IsUnderLocation`	adopt	`IsUnderLocation`	Against the widget's measured pixel rect. False for a geometry with no viewport position at all -- a render-target canvas, a world-space one with no camera.
`USlateBlueprintLibrary`	`AbsoluteToLocal`	adopt	`AbsoluteToLocal`	Assumes the point lies in the widget's own plane, which is true of every 2D interface. Returns false for a canvas whose scaler cannot be inverted -- world space above all, where the raycaster is the right tool.
`USlateBlueprintLibrary`	`LocalToAbsolute`	adopt	`LocalToAbsolute`	Local has its origin at the widget's BOTTOM-left, not Slate's top-left: every other normalized coordinate in this framework already puts zero at the bottom left.
`USlateBlueprintLibrary`	`GetLocalTopLeft`	adopt	`GetLocalTopLeft`	Always zero, because local coordinates are defined from that corner -- the same answer UMG gives for an ordinary widget. Kept so a graph written against UMG reads the same.
`USlateBlueprintLibrary`	`GetLocalSize`	adopt	`GetLocalSize`
`USlateBlueprintLibrary`	`GetAbsoluteSize`	adopt	`GetAbsoluteSize`	Measured from the rect's two projected corners, so a canvas scaler, a render scale and an ancestor's scale are all already in it.
`USlateBlueprintLibrary`	`Scalar_AbsoluteToLocal`	map	`TransformScalarAbsoluteToLocal`	Named for what it transforms rather than with a type prefix. The wider axis decides for a non-uniformly scaled widget, as in UMG.
`USlateBlueprintLibrary`	`Scalar_LocalToAbsolute`	map	`TransformScalarLocalToAbsolute`
`USlateBlueprintLibrary`	`Vector_AbsoluteToLocal`	map	`TransformVectorAbsoluteToLocal`	Per axis, so a non-uniform scale is honoured here where the scalar version has to pick one.
`USlateBlueprintLibrary`	`Vector_LocalToAbsolute`	map	`TransformVectorLocalToAbsolute`
`USlateBlueprintLibrary`	`EqualEqual_SlateBrush`	map	`UDreamUIWidgetLibrary::EqualEqual_DreamUIImageBrush`	This framework's brush is FDreamUIImageBrush, so the node is named for it. Exact on the floats rather than tolerant: the question a caller asks with == is 'did anybody change this brush', and a near-comparison would answer no to a one-pixel nudge. The node lives on the widget library because the other brush verbs do.
`USlateBlueprintLibrary`	`LocalToViewport`	adopt	`LocalToViewport`	Hands back both the pixel position and the DPI-scaled one, as UMG does.
`USlateBlueprintLibrary`	`AbsoluteToViewport`	adopt	`AbsoluteToViewport`
`USlateBlueprintLibrary`	`ScreenToWidgetLocal`	adopt	`ScreenToWidgetLocal`	No bIncludeWindowPosition parameter: a screen position and a viewport pixel position are the same space here, because the framework draws inside the viewport and never against the desktop.
`USlateBlueprintLibrary`	`ScreenToWidgetAbsolute`	adopt	`ScreenToWidgetAbsolute`	Identity, for the reason on the row above. It exists so a ported graph keeps its shape and so the equivalence is stated somewhere.
`USlateBlueprintLibrary`	`ScreenToViewport`	adopt	`ScreenToViewport`

UDreamUIWidgetGeometryLibrary

Functions

Compared with UMG

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