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Inspector Cursor tab — ED.19

In a screen recording the cursor is the only performer on stage — and like any performer it reads better with a little grooming. Scaled up so it's findable, its motion smoothed the way a fluid-head dolly tames handheld jitter, a ripple on each click the way a clapperboard's snap marks the action, and politely off-stage when it isn't doing anything. ED.19 is the cursor's dressing room: a panel that edits one CursorConfig on the project.

flowchart LR
  CTL["size / smoothing / ripples /\nhide-static / auto-zoom"] --> OP["EditOp::SetCursor"]
  OP --> H["edit::History.apply"]
  H --> CUR["project.cursor"]
  CUR --> OVL["cursor overlay at render,\ndriven by the cursor track"]

The CursorInspector exposes size (clamped to a sane 25–400 %), smoothing, and three toggles — click ripples, hide-when-static, and auto-zoom on clicks (the switch that feeds ED.17). Each reads the current config, changes one field, and commits a SetCursor through the shared History. Because CursorConfig is Copy, the op is a plain field assignment — the by-reference apply refactor ED.18 introduced for the non-Copy background config carries it for free.

The overlay at render

The composited cursor is a single wisp Graphics node drawn over the framed screen by EditorPreview::render_framed_with_cursor, driven by the recorded cursor track (EditProject::cursor_track):

  • a scaled, dark-outlined white arrow pointer (a single convex draw_polygon quad — tip, left edge, tail point, right barb — sized by size_pct),
  • expanding, fading click ripples (draw_ellipse discs) at each recent click, radius growing + alpha decaying across a ~0.4 s window (ripples_at),
  • smoothing as a pure EMA over the track (cursor_at),
  • hide-when-static: a parked pointer fades off-stage (cursor_is_static), but a live click ripple keeps it visible — a click is an action worth showing even when the cursor hasn't moved.

The cursor rides the zoom

The captured position is normalized to the source frame, so the overlay is mapped through the same crop / zoom / padding transform as the screen sprite — the pointer stays glued to the exact pixel it was over and magnifies with the auto-zoom punch-in, rather than drifting off the button it clicked. A GPU test asserts the same source point lands further from centre under a zoom (rides-the-transform, not output-space pinning).

The track comes from capture (ED.17)

The overlay renders from a recorded or synthetic track (and is tested with a synthetic one, so it's gate-green without real capture). The recorded track is produced by the per-OS telemetry capture in ED.17. The pointer is a vector arrow glyph and hide_static is honored at render; a pixel-sampled native cursor bitmap remains a possible future nicety, not a gap.