Crate brushkit_preview 

Tip bitmaps for every brush file this workspace reads.

preview_abr, preview_brush and preview_brushset each take the whole file as bytes and return one PreviewEntry per brush in file order, available or not. A brush whose tip cannot be rendered is reported with a reason rather than dropped, so a caller can lay out a complete grid. Each has a _first_available twin that returns only the first n available entries and builds no entry after them.

preview is the function all six call. It also takes a keep_going callback that can stop the call between entries, for a host that shows previews under a time limit.

The available tips of one call hold at most MAX_PREVIEW_BYTES of bitmap data together. Entries past that point are UnavailableReason::OverBudget and their tips are not decoded.

Every function here is pure over &[u8]: no filesystem, no threads, so the crate builds for wasm32-unknown-unknown.

Modules

procreate

Reading Procreate .brush and .brushset archives: the guarded zip and plist readers, the Shape.png decoder and the two name/member lookups the preview API needs.

Structs

ContactSheetConfig

GrayscaleBitmap

PreviewEntry

PreviewError

PreviewOptions

PreviewSet

SheetBrush

SourceDimensions

File-declared raster dimensions, independent of the returned preview size. A readable header does not guarantee valid pixels or a safe allocation size.

Enums

Format

The kind of brush file preview reads.

SheetBackground

Take

Which entries a preview returns.

TipImageError

TipPreview

UnavailableReason

Constants

MAX_IMPORT_DECODED_BYTES

The decode budget of decode_tip_image. TipImageError::TooLarge lists what it reserves.

MAX_IMPORT_DIMENSION

MAX_PREVIEW_BYTES

The most bytes of bitmap data (GrayscaleBitmap::data) the Available tips of one preview call, or one call of a function built on it, hold together.

Functions

can_synthesize

decode_tip_image

Decode an imported brush-tip image (PNG/JPEG bytes) into a grayscale tip buffer. Alpha becomes intensity when the image has an alpha channel; otherwise luminance is inverted (dark = opaque), matching Photoshop’s convention.

downsample

Box-filter bitmap so its larger side is at most max_side (>= 1). Returns a clone when it already fits. Average of the covered source pixels per destination pixel, the same filter generate_preview_png uses.

generate_contact_sheet_png

generate_preview_png

A 200 px RGBA thumbnail: black ink, alpha from the tip’s gray value.

preview

Tips for a brush file of format, as take selects them.

preview_abr

Tips for a Photoshop .abr pack.

preview_abr_first_available

The first n entries of preview_abr whose tip is available, in the same order and with the same index they have there, so indices may skip. Unavailable entries do not count toward n, and entries after the nth available one or after the first OverBudget one are not built, so their tips are not decoded or downsampled.

preview_brush

The tip of a single Procreate .brush: one entry at index 0, read from the archive’s root rather than from a member directory.

preview_brush_first_available

preview_brush limited to available tips: its single entry when the tip is available and n >= 1, otherwise no entries. With n == 0 the tip is not decoded.

preview_brushset

Tips for a Procreate .brushset.

preview_brushset_first_available

The first n entries of preview_brushset whose tip is available, in the same order and with the same index they have there, so indices may skip. Unavailable entries do not count toward n, and members after the nth available one or after the first OverBudget one are not read.

synthesize_computed_tip

Rasterize a monochrome elliptical tip from computed-brush geometry.

tip_bitmap_of

Both formats use the same polarity — a Shape.png is white=stamp coverage and a TipBitmap is 255=full ink — so the pixels are copied unchanged.

to_grayscale