Overview
blinc_canvas_kit is the layer that turns Blinc’s raw GPU-drawing primitives into an authoring surface. It sits on top of the canvas() element and provides four building blocks:
| API | When to reach for it |
|---|---|
| Sketches | Per-frame immediate-mode drawing with persistent state — particle systems, generative art, live visualisations. |
| Players | Time-based animation sources (Lottie, Rive, custom scene formats) driven by an external t. |
| CanvasKit | Interactive 2D canvases: pan, zoom, hit-testing, pointer / drag / selection callbacks. |
| SceneKit3D | 3D scene authoring: orbit camera, lights, environment maps, mesh draw, gizmos. |
All four share a common principle: the kit owns the per-frame render loop and whatever persistent state the drawing needs, then exposes a small trait (Sketch, Player) or a handle (CanvasKit, SceneKit3D) you feed into a Div tree. State survives UI rebuilds via use_state_keyed, so layout changes, hot reload, and route transitions don’t reset counters, particle systems, camera poses, or asset uploads.
Reach for raw canvas() only when you want a one-shot static render with no animation loop and no persistent state — for example, a chart drawn from a one-time computation.
Import surface
Everything in this chapter lives under the prelude:
#![allow(unused)]
fn main() {
use blinc_canvas_kit::prelude::*;
}The prelude re-exports Sketch, SketchContext, Painter2D, Player, sketch, CanvasKit, SceneKit3D, OrbitCamera, and the relevant event types. Explicit imports work too — everything is in blinc_canvas_kit or blinc_canvas_kit::sketch.
Animation cadence
Every kit runs its draw callback at the host’s redraw cadence (typically vsync: 60 / 120 Hz) by requesting another frame at the end of each render. There is no opt-out from inside a Sketch — if you want static output, use plain canvas() directly. For deterministic playback (recording frames, scrubbing), drive a Player from outside a sketch and pass synthesised t values.