@azphalt/importer-abr

Normalize a Photoshop .abr brush into a .azp asset package. Unlike .cube (stored verbatim), .abr is transcoded: the sampled brush tip is decoded to a grayscale PNG and its mappable dynamics are lifted into the manifest — spec/package-format.md requires "an imported .abr [to become] assets/*.png plus manifest params, not a repackaged .abr". You import the portable half — shape, grain, mappable parameters — not the stroke engine, so it is a faithful-shape import, not a pixel-match (RATIONALE § 1.3).

Coverage

• v1 / v2 sampled brushes — bounds, spacing, raw or PackBits (RLE) bitmap.
• v6+ 8BIM sections — samp sampled bitmaps + desc dynamics (diameter, spacing, angle, roundness, hardness) from the action descriptor.
• Computed (procedural) brushes carry no bitmap and are skipped. Any unrecognized version or structure throws UnsupportedAbrError — the importer never emits a guess.

Validation status: the decoders are covered by tests built from the documented layout with an independent byte writer (so a passing test cross-checks reader against writer, not the parser against itself), plus the canonical PackBits vector and a PNG decode round-trip. Validating against a corpus of real Photoshop .abr files is the next step before claiming full Photoshop compatibility.

CLI

pnpm --filter @azphalt/importer-abr build
azphalt-import-abr dry-ink.abr --id com.hereliesaz.dry-ink -o dry-ink.azp
# real packaging supplies the brush's own license text:
azphalt-import-abr dry-ink.abr --id com.hereliesaz.dry-ink --license-file LICENSE.txt

Library

import { importAbr, parseAbr } from "@azphalt/importer-abr";

const { azp, manifest, brush } = importAbr(abrBytes, licenseText, { id: "com.hereliesaz.dry-ink" });