document.export {format: "png8" | "gif"} reduces the art to a palette of at most `colors`
(2–256) entries: median cut over a 15-bit histogram refined by k-means (perceptual,
selective or adaptive weighting), or the web-safe, black-and-white or grey palettes; art
with that many colours or fewer keeps them exactly. Dithering is Floyd–Steinberg diffusion,
an 8×8 ordered pattern or noise, with an amount. Pixels under half opacity become one
transparent entry; partly transparent edges blend over the matte. PNG-8 is an indexed PNG
(PLTE, tRNS, 1–8 bits per pixel, Adam7); GIF is a GIF89a (optionally interlaced). Both are in
document.formats, Export As (PNG-8 / GIF Options dialogs) and Export for Screens.
document.formats' writable list and the MCP export tool's format enum gain gif and png8
(their tests list them).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
file.info takes and reports the title, author, author title, description,
keywords, rating, copyright status, notice and URL in one undo step, plus
the read-only created (file.new) and modified (every save to a file) dates;
junk values are refused. Document.metadata (DocMetadata) round-trips
natively. PDF export writes author, subject and keywords to the info
dictionary and XMP, PNG export writes tEXt/iTXt chunks, SVG export writes
<desc> and, with the metadata option, every field as Dublin Core. The File
Info dialog (fileInfo, ui.fileInfoDialog) edits it with keyword chips and
star ratings.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
PNG is written by an in-code chunk writer with the resolution in pHYs and optional Adam7
interlacing (JPEG stores the resolution in JFIF). document.export takes ppi (72/150/300/other,
wins over scale), background (transparent, white, black or a colour) and antiAlias (none, art,
type: text snapped to whole pixels); Export for Screens rows take them too (plus one top-level
antiAlias, and a row's ppi names its @Nx suffix), and so does object.rasterize. Hard edges stay
hard in every offscreen pass (groups, masks, filters), whatever the thread count.
RenderOptions.anti_alias and render::encode::RasterExportOptions; PNG/JPEG/WebP Options dialog
(pngOptions/jpgOptions/webpOptions) after File > Export As PNG.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>