Fix #3911: EMF export writes a pattern fill as one shape per part of its tile

A pattern fill was written to EMF as every tile's art, each tile in a clip
of its own, with the brush made again for each part: a rotated two-colour
stripe fill of a 360 x 260 pt rectangle took 473 fills, 246 clips and
122 KB.

When the tiles can't overlap (a grid or brick tiling whose art stays in its
tile), each tile's clip is left out where what it clips lies inside it
already (a convex clip holding every control point of the fills), and the
n-th fill of every tile becomes one path. The picture is the same: the
tiles don't overlap, and the fill's own clip still trims them. That fill
is now 2 fills and 1 clip, 61 KB; unrotated, 99 KB becomes 33 KB.

Tiles that overlap, hex tilings, and tiles holding strokes, images or
clips that cut are written as before, their parts off the page left out.

docs/file-format-parity.md

@@ -133,6 +133,7 @@ the app's own editing copy of a file (an EPS after its `%%EOF`, a `.ai`'s `AIPri
 |---|---|---|
 | 2026-10-29 | minor | `.ai` and Illustrator EPS import: the editing data is read up to an eighth of installed memory, from 512 MiB to 2 GiB on 64-bit builds (it was 512 MiB on every machine), so a layered file whose embedded rasters unpack past 512 MiB keeps its layers, groups and text on a machine with 8 GiB or more instead of opening as its page or PDF part (#3510, #4628). Measured: 1.1 GB of editing data peaked 1.1 GB above the start; data past the limit is still refused (a 2 MB file unpacking to 2.2 GB stops in under a second). 32-bit and web builds keep 256 MiB. Own-fixture tests `import::ai::tests::editing_data_past_512_mib_is_read_where_memory_allows`, `the_editing_data_limit_follows_installed_memory`; scores and hours unchanged |
 | 2026-10-29 | minor | Affinity import: attached Recolor Adjustment (RcRA) layers import as color overlays with HSL lightness (#4420); scores unchanged. |
+| 2026-10-30 | minor | EMF export: a pattern fill whose tiles stay apart (grid and brick tilings, art inside its tile) is written as one shape for each part of the tile, clipped once to what it fills, instead of every tile in a clip of its own; the picture is the same. A rotated two-colour stripe fill goes from 473 shapes and 246 clips to 2 shapes and 1 clip (122 KB to 61 KB; unrotated 99 KB to 33 KB). Tiles that overlap, hex tilings and tiles with strokes, images or nested clips are written as before (#3911). Tests in `crates/metafile/src/tests.rs` and `scene::merge_tests`; scores and hours unchanged |
 | 2026-10-26 | minor | EPS Save and Save As: an opened EPS saves back to its own path as EPS, keeping the chosen artboard's page frame and transparent margins and the complete editable VectorCraft document; Save's TIFF preview is capped at 1024 px (Export keeps 2048); partly read, preview-only or damaged-editing-data sources still need confirmation before they are overwritten; Save As leaves out the export-only crop and selection options. Synthetic regressions in `tests::save` (engine and UI) and `dialogs::save_options::tests`, listed under [EPS Save and source protection](#eps-save-and-source-protection); it does not write Illustrator's own editing data (#868), and G9's real-file import fidelity is unchanged; scores and hours unchanged |
 | 2026-10-25 | minor | `.ai` import: the editing data is read up to 512 MiB on 64-bit builds (the limit was 256 MiB), so a file whose embedded rasters unpack to 300 MiB or more keeps its layers, groups and text instead of opening as its PDF part (part of #3510); 32-bit and web builds keep 256 MiB. Own-fixture test `import::ai::tests::editing_data_past_256_mib_is_read`; scores and hours unchanged |
 | 2026-10-25 | minor | `.ai` import: the `--` placeholder of a radial gradient's highlight (`-- -- angle length Bh`, a gradient without one) and the `XC` operator after a linked image's file name no longer send the whole file to its PDF part, so files with them keep their layers, groups and live text (#4176). A `--` anywhere else is still an operator the reader doesn't know. Own-fixture tests in `import::ai::tests`; scores and hours unchanged |