rasterlottie 0.2.1

Pure Rust, headless Lottie rasterizer for deterministic server-side rendering
Documentation 
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<!doctype html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <title>rasterlottie reference renderer</title>
    <style>
      html,
      body {
        margin: 0;
        padding: 0;
        background: transparent;
      }

      #container,
      canvas {
        display: block;
      }
    </style>
  </head>
  <body>
    <div id="container"></div>
    <script src="https://cdn.jsdelivr.net/npm/lottie-web@5.13.0/build/player/lottie.min.js"></script>
    <script>
      async function main() {
        const params = new URLSearchParams(window.location.search);
        const fixtureName = params.get("fixture");
        const frame = Number(params.get("frame") ?? "0");
        if (!fixtureName) {
          throw new Error("Missing fixture query parameter.");
        }

        const response = await fetch(`../fixtures/${fixtureName}`);
        if (!response.ok) {
          throw new Error(`Failed to fetch fixture ${fixtureName}: ${response.status}`);
        }

        const animationData = await response.json();
        const width = Number(animationData.w);
        const height = Number(animationData.h);
        if (!Number.isFinite(width) || !Number.isFinite(height)) {
          throw new Error(`Fixture ${fixtureName} does not define finite width and height.`);
        }

        const container = document.getElementById("container");
        container.style.width = `${width}px`;
        container.style.height = `${height}px`;

        window.__referenceReady = false;
        const animation = lottie.loadAnimation({
          container,
          renderer: "canvas",
          loop: false,
          autoplay: false,
          animationData,
          rendererSettings: {
            clearCanvas: true,
            preserveAspectRatio: "xMidYMid meet",
          },
        });

        const renderFrame = async () => {
          animation.goToAndStop(frame, true);
          await new Promise((resolve) =>
            requestAnimationFrame(() => requestAnimationFrame(resolve)),
          );
        };

        await new Promise((resolve, reject) => {
          animation.addEventListener("data_failed", () => reject(new Error("data_failed")));
          animation.addEventListener("DOMLoaded", () => resolve());
          if (animation.isLoaded) {
            resolve();
          }
        });

        await renderFrame();
        window.__referenceReady = true;
      }

      main().catch((error) => {
        console.error(error);
        window.__referenceError = String(error);
      });
    </script>
  </body>
</html>