Module image_viewer 

Interactive image viewer with pan + zoom semantics, unlike the static crate::widget::Image widget: scroll-wheel zoom, click-drag pan, and a deterministic “fit to viewport” reset. Interaction state (zoom, pan, drag origin) lives on the widget directly; CRDT reflection is out of scope.

Coordinate model: zoom == 1.0 is the “contain” baseline (mirrors CSS object-fit: contain). Higher zooms multiply that baseline scale, and pan is an image-space offset applied after it — storing pan in image space rather than pixels keeps drag velocity constant across zooms. Scroll-wheel zoom centres on the cursor by re-projecting the image-space point under it before/after the scale change and nudging pan to keep that point fixed on screen — otherwise zooming “to a feature” would feel like the image sliding away from the pointer.

Structs

ImageViewer

Interactive viewer for a pre-decoded peniko::ImageData. See module docs for the contract.

ImageViewport

Pure photo viewport geometry shared by live widgets and immutable History.