Module scroll 

Wheel and drag scrolling with optional momentum.

Low-level scroll algorithms (MomentumScroller, HardScroller) accumulate per-axis offsets. Element managers combine wheel input, optional mouse drag, and layout bounds to produce clamped scroll positions.

Scroll positions use 0.0 when content is aligned to the top-left of the clip region. Scrolling content up or left produces negative values. Valid range per axis is [−limits, 0] where limits = (internal_size − bound_size).max(0).

Layout bounds come from cotis_utils::element_state::ElementBoundingBox and internal content size from cotis_utils::element_state::ElementClipInternalSize.

Structs

DoubleAxisScrollElementManager

Per-element two-axis scroll manager with wheel, optional drag, and clamping.

DoubleAxisScrollManager

Independent scroll algorithms for horizontal ([0]) and vertical ([1]) axes.

HardScroller

Direct scroll offset without momentum.

MomentumScroller

Scroll offset with velocity-based momentum and frame-rate-independent friction.

SingleAxisScrollElementManager

Per-element single-axis scroll manager with wheel, optional drag, and clamping.

Enums

ScrollAlgorithm

Per-axis scroll algorithm wrapper.

SingleAxisScrollManager

Scroll manager for a single axis.

Traits

FullElementScrollState

Combines cursor state, wheel input, and layout bounds for element scrolling.