Fitting a state onto the picture it came from (v0.51.0–v0.52.1) · Sprite Manager devlog

A new fit, on_tile, places an upload on an accepted picture by searching scale and shift for the best pixel match, then keeps the accepted picture's own pixels everywhere the upload didn't change them. A state (a fridge with food in it) is then the base picture exactly, except where it differs. It works when most of the picture survives, and says so when it doesn't: an open lid matched only a third of the closed fridge.
For that case, fit_scale fixes a file's scale to another file's, so frames cut from one image stay the same size, and well_only makes an overlay transparent outside the part that changes.
A near miss worth recording: the key was first called scale, which the spec table already uses for pixels per tile. Every piece was fitted 192 times too big. Renamed, and refitted from the untouched originals.
Sprite numbers are now a running total that goes past 999, at the Owner's request, so the count of every sprite ever asked for stays readable. The 26 numbered after the old wrap became 1000-1025.
A grid image dropped on a card whose files were all already accepted used to vanish without a trace. It's kept in the inbox with a note now, like every other upload the app can't file.