ProCraft

By surfrpt1.

An open-source, clean-room raster painting studio in pure Rust: layered painting, a soft-round brush engine, and PNG import/export. Inspired by professional painting workflows; every line of code and every asset here is original.

Trademark note: "Procreate" is a registered trademark of Savage Interactive. ProCraft is an independent project with its own name, branding and code, and is not affiliated with or endorsed by any other vendor.

Signed builds for all three targets on the releases page:

Android files live in the app's external folder (Android/data/com.surfrpt1.procraft/files, reachable over USB): the in-app Import browser reads it, and saves land there, then appear in Photos after a media scan.

• Layered document model (add / hide / reorder / opacity / blend)
• Soft-round brush + eraser with spacing, dynamics and undo
• egui desktop app: paint, layers panel, color/size sliders, PNG export
• Project files (.procraft v10 with masks, clipping + 10 blends, layer offsets, mirror center, groups + group opacity, frame holds; v1-v9 still open), pinch-to-zoom, themes, page colors with active-preset highlight
• Rectangular + freehand lasso selections constraining paint
• Flood fill bucket with tolerance (selection-aware, symmetry-mirrored) + ColorDrop threshold-drag (hold + drag sweeps 0-255 with live preview, one undo step)
• Move tool (drag active layer), shape tools (line/rect/ellipse/triangle/diamond/star/arrow/polygon + fill)
• Layer transforms (scale, rotate, flip H/V with bilinear sampling)
• Mirror symmetry painting (horizontal / vertical / both + axis overlay) with movable center (drag on canvas, edge parking, Reset, saved)
• Layer filters: brightness/contrast, box blur, unsharp sharpen (selection-masked) with live snapshot preview (scrub, then Apply keeps; one undo step per gesture)
• Kaleidoscope symmetry (2-16 segments), layer rename/duplicate/merge, eyedropper, honest brush previews
• Non-destructive layers: reveal masks (paint luminance, eraser reveals, mask viewer), clipping masks, 10 blend modes (masks travel with transforms, merge bakes them)
• Layered PSD interchange: export keeps names/opacity/blends/clipping/transparency/masks/groups for Photoshop/Procreate/Krita/GIMP; import restores structure including nested groups (masks, collapse state and exotic blends documented gaps)
• Compressed project files (PCRAFT04 zlib per layer; verified 12MB → 107KB on a 3-layer painting, corrupt payloads rejected)
• Brush library: named custom brushes with honest clickable previews + active highlight, .pcbrush set import/export (validated, max 64)
• Pro brush interop: import Photoshop .abr (v6-v10 sampled tips + names/spacing via UUID linkage, verified on real Photoshop 2026 files), Procreate .brush/.brushset (Shape tips), Clip Studio Paint .sut (SQLite variant settings + embedded tips), Krita .kpp/.bundle (verified on Krita repo presets: MaskGenerator diameter, Opacity x Flow, embedded tips), GIMP .gbr, tip images; export grayscale tip PNGs for other software
• Shape tools wave 2 (triangle/diamond/star/arrow/3-12-sided polygon, outline + fill), collapsible sidebars + wrapped top bar for portrait/iPad, off-page-stroke crash fix, touch-sized layer rename (Save/Cancel)
• Native iOS build (target-gated eframe/rfd-shim, CI-built IPA sideload, v5 at v0.6.0): document-picker imports, Documents saves + share sheet, async opens, touch-force pressure, post-open repaint fix
• About dialog (app-centered; auto version, builder, repo + check-for-updates links, MIT line)
• Brush dynamics: pressure/velocity size + opacity curves, grain + scale, roundness, angle-follow rotation, scatter, stabilizer smoothing (old .pcbrush files load identically)
• Palettes: multi-palette manager (up to 16 named sets, rename/delete, per-palette import/export), .pcpalette save/open, GIMP .gpl import, starter set, HSL + complementary/triadic/analogous harmonies, full-height 3x8 swatch grids; drawing guides (off/square/iso/1pt/2pt) with canvas overlay + snap (iso-lattice and vanishing-point rays, Snap-range magnet) and draggable vanishing points (canvas handles, edge parking, Reset)
• Animation Assist: layers-as-frames, play/stop + FPS stepping, forward/ping-pong loop + frame hold, onion skins (red/blue ghosts + amount), GIF export (1-60fps, infinite loop) and GIF import back to editable layers (hidden layers skipped in playback and export)
• Text tool: click-to-anchor, multiline 8-128px dialog, bundled Inter (OFL, latin subset, fontdue raster), bakes to layer in one undo step
• Lossless layer moves: O(1) offsets (off-canvas content preserved, undoable), offset-aware paint/flood/text/merge/flip/affine/masks/animation/PSD
• Micro-steppers (−/+ on every slider), compact tools panel
• Drawing Assist: strokes lock to guides while drawing (perspective nearest-ray incl. draggable VPs, square/iso dominant axis; 4px deadzone, parked-on-VP and Off paint free) with checkbox + hint and amber lock-line overlay (brush + eraser)
• Selection Studio: feather/grow-shrink/smooth/invert/select-opaque/outline in a collapsing group, 0-255 weighted masks (graduated coverage through paint/tone/blur/sharpen, flood binary-gated), bbox-retightened rect ants, stamp-path feather fix
• Layer groups: nested model with effective visibility, panel tree (collapse/eye/rename/+Add/Ungroup), per-group opacity in compositing/frames, PSD group round-trip
• Smudge tool (finger pickup, Strength slider), canvas rotate (twist gesture + slider/Reset), two-finger-tap undo / three-finger-tap redo, autosave + crash recovery (silent snapshots, Recover/Discard prompt)
• JPEG export with quality slider + lossless TIFF export; drag-crop rect + pad/trim canvas resize with anchor (offsets carry content)
• Pick tool with magnifier loupe ring (Alt-pick too), palette-from-image and palette-from-canvas import
• Animation frame UI: duplicate frame, per-frame hold (playback + GIF round-trip timing), onion strength per side
• Adaptive top bar: all groups flow inline and fold to 2+ lines on narrow displays (phone portrait, small windows) instead of overlapping
• Native Android build (NativeActivity + wgpu, cargo-apk sideload APK, ARM64 + x86_64 universal, release-signed): touch paint, adaptive bar, in-app Import browser over USB (Android/data/...), external saves with media scan
• Gallery/file browser (M33): new/open/recent with thumbnails; Reference companion (M34); Selection upgrades (M35): save/load, nudge/flip; Adjustments (M36/M37): Curves/Levels + HSL/Balance/Recolor
• Typography (M38): TTF/OTF import, leading/tracking/outline; Brush depth (M39); Liquify-lite (M40); Time-lapse snapshots (M41); iPad layout polish (M42)
• Transform depth (M43/M44): corner-pin distort + warp mesh (masks travel); Stability hardening (M45): fuzz open, OOM guards; SAF picker (M46); Palm rejection + Pencil (M47)
• Touch workflow: Hand pan tool (margin-grab fix), Pencil + two-finger pan, shift+wheel horizontal pan, hidden scrollbars, tap undo/redo
• On-canvas transform handles (M48): distort, skew, perspective, free, and warp-mesh handles with live preview, release-apply, Reset / Esc cancel
• Puppet Warp (M48): active-pin ring, Alt/Delete-pin tool, Shift/marquee multi-select, group move, expandable mesh; deleting a pin restores its effect, and undo/layer changes re-arm instead of warping stale pixels
• Settings + keybinds (M49): cross-platform settings.json (seed-once from legacy ui.json, corrupt-file quarantine), Shortcuts editor with exact-chord dispatch (Ctrl+Shift+Z fixed), Shift+drag brush size
• Editable text layers (M50): Procreate-style re-editable text (tap to select / re-edit / move), Rasterize bakes to pixels, v11 project format (v1-v10 still open), paint-guard hint on text layers
• Tablet/phone top bar: folded view cluster, touch-sized View ▾ / File ▾ menus, drag-collapse panel sections, iOS safe-area refold, Android status-bar inset
• Input fixes: motionless click/tap paints a dab (brush/eraser/smudge), text opens on drag-start, iPad tap positions read from interact_pointer_pos (hover_pos is None on touch-tap frames)
• Polish: Android adaptive launcher icon, region-local animation-assist rasterize (385x faster paint ticks), shape drag preview traces the selected shape, no console window in release builds

Original layer-stack mark drawn natively in VectorCraft (headless batch; assets/icon-generator.py replays the whole construction, assets/icon.svg is the editable source). Shipped as the window icon and the embedded exe icon.

Needs Rust 1.88+ (rustup):

git clone https://github.com/surfrpt1/procraft.git
cd procraft
cargo run --release -p procraft

• iOS: rustup target add aarch64-apple-ios && cargo check -p procraft --target aarch64-apple-ios (test IPAs are cut by the ios-ipa CI workflow).
• Android: install the Android NDK, cargo install cargo-apk, then cargo apk build -p procraft --lib (the android-apk CI workflow builds, signs and uploads test APKs; the release profile needs the private release keystore, maintainer-only).

• crates/engine — document, layers, brush dabs, undo, PNG I/O (no GUI).
• apps/procraft — egui app (Windows/macOS/Linux desktop, iOS, Android; the app lives in src/lib.rs, with a thin src/main.rs desktop entry and android_main for NativeActivity).
• crates/rfd-shim — file-dialog shim for mobile (iOS document-picker bridge, Android external-files + media scan).

MIT — see LICENSE-MIT.