Struct DragState 

pub struct DragState { /* private fields */ }

Pure-math drag state tracker.

Tracks pointer position, computes velocity via exponential moving average, and applies constraints. No DOM dependency.

Implementations

impl DragState

pub fn new() -> Self

Create a new drag state with no constraints, positioned at origin.

pub fn with_constraints(self, constraints: DragConstraints) -> Self

Set constraints (builder-style).

pub fn with_position(self, position: [f32; 2]) -> Self

Set initial position (builder-style).

pub fn on_pointer_down(&mut self, x: f32, y: f32)

Called when a pointer/mouse/touch press begins.

pub fn on_pointer_move(&mut self, x: f32, y: f32, dt: f32)

Called each frame while the pointer is held down.

dt is the time since the last move event (for velocity calculation).

pub fn on_pointer_up(&mut self) -> InertiaN<[f32; 2]>

Called when the pointer is released. Returns an InertiaN carrying the momentum from the drag.

pub fn position(&self) -> [f32; 2]

Current drag position.

pub fn velocity(&self) -> [f32; 2]

Current velocity (smoothed).

pub fn is_dragging(&self) -> bool

Whether the pointer is currently held down.

Trait Implementations

impl Clone for DragState

fn clone(&self) -> DragState

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for DragState

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for DragState

fn default() -> Self

Returns the “default value” for a type.