video/.agents/skills/remotion-best-practices/rules/charts.md

name, description, metadata

name	description	metadata
charts	Chart and data visualization patterns for Remotion. Use when creating bar charts, pie charts, line charts, stock graphs, or any data-driven animations.	tags charts, data, visualization, bar-chart, pie-chart, line-chart, stock-chart, svg-paths, graphs

Charts in Remotion

Create charts using React code - HTML, SVG, and D3.js are all supported.

Disable all animations from third party libraries - they cause flickering.
Drive all animations from useCurrentFrame().

Bar Chart

const STAGGER_DELAY = 5;
const frame = useCurrentFrame();
const { fps } = useVideoConfig();

const bars = data.map((item, i) => {
  const height = spring({
    frame,
    fps,
    delay: i * STAGGER_DELAY,
    config: { damping: 200 },
  });
  return <div style={{ height: height * item.value }} />;
});

Pie Chart

Animate segments using stroke-dashoffset, starting from 12 o'clock:

const progress = interpolate(frame, [0, 100], [0, 1]);
const circumference = 2 * Math.PI * radius;
const segmentLength = (value / total) * circumference;
const offset = interpolate(progress, [0, 1], [segmentLength, 0]);

<circle
  r={radius}
  cx={center}
  cy={center}
  fill="none"
  stroke={color}
  strokeWidth={strokeWidth}
  strokeDasharray={`${segmentLength} ${circumference}`}
  strokeDashoffset={offset}
  transform={`rotate(-90 ${center} ${center})`}
/>;

Line Chart / Path Animation

Use @remotion/paths for animating SVG paths (line charts, stock graphs, signatures).

Install: npx remotion add @remotion/paths
Docs: https://remotion.dev/docs/paths.md

Convert data points to SVG path

type Point = { x: number; y: number };

const generateLinePath = (points: Point[]): string => {
  if (points.length < 2) return "";
  return points.map((p, i) => `${i === 0 ? "M" : "L"} ${p.x} ${p.y}`).join(" ");
};

Draw path with animation

import { evolvePath } from "@remotion/paths";

const path = "M 100 200 L 200 150 L 300 180 L 400 100";
const progress = interpolate(frame, [0, 2 * fps], [0, 1], {
  extrapolateLeft: "clamp",
  extrapolateRight: "clamp",
  easing: Easing.out(Easing.quad),
});

const { strokeDasharray, strokeDashoffset } = evolvePath(progress, path);

<path
  d={path}
  fill="none"
  stroke="#FF3232"
  strokeWidth={4}
  strokeDasharray={strokeDasharray}
  strokeDashoffset={strokeDashoffset}
/>;

Follow path with marker/arrow

import {
  getLength,
  getPointAtLength,
  getTangentAtLength,
} from "@remotion/paths";

const pathLength = getLength(path);
const point = getPointAtLength(path, progress * pathLength);
const tangent = getTangentAtLength(path, progress * pathLength);
const angle = Math.atan2(tangent.y, tangent.x);

<g
  style={{
    transform: `translate(${point.x}px, ${point.y}px) rotate(${angle}rad)`,
    transformOrigin: "0 0",
  }}
>
  <polygon points="0,0 -20,-10 -20,10" fill="#FF3232" />
</g>;