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Crop + aspect reframe — ED.15

Aspect ratio used to be a piece of metal. A hard matte in the camera or optical printer blacked the frame down to 16:9, or 4:3, or anamorphic 2.35 — the shape was masked into the negative. Releasing a 4:3 negative to a 16:9 screen meant pan-and-scan: an operator chose, frame by frame, which window of the image to keep. ED.15 makes both into values — the matte (aspect) and the chosen window (crop) — stored on the project and re-derived at export, so the same source reframes to a widescreen export or a vertical short without ever recutting it.

flowchart LR
  A["aspect preset (16:9 / 9:16 / 1:1 / 4:3)"] --> OPA["EditOp::SetAspect"]
  C["crop %  (X / Y / W / H)"] --> OPC["EditOp::SetCrop"]
  OPA --> H["edit::History.apply"]
  OPC --> H
  H --> P["project.aspect / project.crop"]
  P --> CANVAS["aspect.canvas_dims → export canvas"]
  P --> FRAME["crop sub-rect → render_framed / videocrop"]

The FramingInspector carries both: aspect-ratio presets (the matte) and four numeric crop fields as percentages (the window), with a reset to full frame. Each runs EditOp::SetAspect / EditOp::SetCrop through the shared History, so reframing is undoable. SetCrop sanitizes the rect to a valid in-frame sub-rect (non-zero extent, inside [0, 1]), and a full-frame crop is stored as no crop so the export can skip the videocrop element entirely.

Authoring now; the visible reframe at render

ED.15 ships the authoring side — the ops + the inspector. The aspect ratio becomes the export canvas via AspectRatio::canvas_dims (already used by the export plan), and the crop becomes a sub-rect of the screen sprite. The visible reframe — preview reshaping live and the export honoring the crop — lands with the render-integration / export pass (ED.20 / ED.21), whose render_framed composes crop-then-zoom into the screen sprite's transform. The 25/50/75 % rule-of-thirds grid guides are a preview overlay that lands with that same pass.