fast_rust 0.3.0

Rust-powered kernels for Flutter and Dart over zero-copy dart:ffi: path tracing, photo recoloring, photo to coloring page, flood fill, falling sand.

0.3.0

• Path tracing: FastRust.pathTrace adds samples of a built-in 3D scene to a running average, on all CPU cores. The scene has glass, metal and diffuse spheres on a checkered floor under a sky, with soft shadows, reflections, refraction and depth of field. FastRust.pathResolveRgba turns the average into RGBA, and RayCamera orbits the scene. One sample per pixel of a 480×360 frame takes about 5 ms on 8 desktop threads.
• DartReference.pathTrace matches Rust bit for bit. The kernel only uses + - * /, sqrt and floor, and the camera's trigonometry is computed once in Dart.

0.2.0

• Photo to coloring page: FastRust.photoToColoringPage (and ...Async) turns a photo into black outlines on white, ready to fill. It blurs, quantizes colours with k-means, removes speckles with a majority filter, merges regions smaller than minRegion, and draws lineWidth-pixel outlines plus a frame. Returns a ColoringPage with the page, a label map and the photo's palette (for a "reveal" or color-by-number mode).
• Falling sand: FastRust.sandStep advances a sand/water/wall grid by one deterministic step; FastRust.sandRenderRgba draws it. Cell values are in SandMaterial.
• spreadDistancesRgba and paintByDistanceRgba now reject a distances buffer that overlaps the image buffers.
• DartReference versions of all new kernels, matching Rust bit for bit.

0.1.0

• Initial release. Rust kernels called through zero-copy dart:ffi @Native functions; a native-assets build hook runs cargo for the target platform (Android, iOS, macOS, Linux, Windows).
• Photo recoloring: FastRust.recolorRegionRgba selects a connected region of a real image by color tolerance (magic wand) and tints it while keeping each pixel's brightness, so texture survives.
• Pixel-art coloring: floodFillRgba (scanline bucket fill with tolerance) and coloringPageRgba (generated coloring pages).
• Image processing: multi-threaded boxBlurRgba (O(pixels) for any radius) and grayscaleRgba.
• sha256, sortFloat64 (IEEE-754 total order), countPrimes, dot, and a multi-threaded mandelbrotRgba.
• ...Async variants run on a background isolate with non-leaf calls.
• DartReference: pure-Dart versions of every kernel, used by the tests to check that Rust output matches bit for bit.