Build Color Wheel

Let's build a 2D color wheel step by step.

Here's what we'll end up with:

Click to view the full code

ColorWheelGuide.tsx

import "internationalized-color/css";
import { ColorWheel, useColor } from "@urcolor/react";

export default function ColorWheelGuide() {
  const { color, setColor } = useColor("hsl(210, 80%, 50%)");

  return (
    <ColorWheel.Root
      value={color}
      onValueChange={setColor}
      colorSpace="hsl"
      channelAngle="h"
      channelRadius="s"
      className="relative block size-64 overflow-hidden rounded-full"
      style={{ containerType: "inline-size" }}
    >
      <ColorWheel.Gradient className="absolute inset-0 block" />
      <ColorWheel.Thumb
        className="
          size-4 rounded-full border-2 border-white
          shadow-[0_0_0_1px_rgba(0,0,0,0.3),0_2px_4px_rgba(0,0,0,0.3)]
          focus-visible:shadow-[0_0_0_1px_rgba(0,0,0,0.3),0_0_0_3px_rgba(66,153,225,0.6)]
        "
        aria-label="Color"
      />
    </ColorWheel.Root>
  );
}

Step 1: Set up state

Start by importing the color hook and creating color state.

import { useColor } from "@urcolor/react"; 

function MyWheel() {
  const { color, setColor } = useColor("hsl(210, 80%, 50%)"); 
}

Step 2: Add the root

ColorWheel.Root manages all the state and interactions. Tell it which color space and channels to map to the angle and radius.

import { useColor, ColorWheel } from "@urcolor/react"; 

function MyWheel() {
  const { color, setColor } = useColor("hsl(210, 80%, 50%)");

  return (
    <ColorWheel.Root
      value={color}
      onValueChange={setColor}
      colorSpace="hsl"
      channelAngle="h"
      channelRadius="s"
    >
      {/* children go here */}
    </ColorWheel.Root>
  );
}

• colorSpace — the color space to work in (hsl, oklch, etc.)
• channelAngle — the channel mapped to the angular axis (rotation)
• channelRadius — the channel mapped to the radial axis (distance from center)

Step 3: Add the gradient

ColorWheel.Gradient renders the 2D circular gradient on a canvas.

import { useColor, ColorWheel } from "@urcolor/react";

function MyWheel() {
  const { color, setColor } = useColor("hsl(210, 80%, 50%)");

  return (
    <ColorWheel.Root
      value={color}
      onValueChange={setColor}
      colorSpace="hsl"
      channelAngle="h"
      channelRadius="s"
      className="relative block size-64 overflow-hidden rounded-full"
      style={{ containerType: "inline-size" }}
    >
      <ColorWheel.Gradient className="absolute inset-0 block" /> {}
    </ColorWheel.Root>
  );
}

The root needs overflow-hidden rounded-full to clip the gradient to a circle, and container-type: inline-size so the component can calculate dimensions correctly.

Step 4: Add the thumb

ColorWheel.Thumb is the draggable handle. It's positioned automatically within the wheel.

import { useColor, ColorWheel } from "@urcolor/react";

function MyWheel() {
  const { color, setColor } = useColor("hsl(210, 80%, 50%)");

  return (
    <ColorWheel.Root
      value={color}
      onValueChange={setColor}
      colorSpace="hsl"
      channelAngle="h"
      channelRadius="s"
      className="relative block size-64 overflow-hidden rounded-full"
      style={{ containerType: "inline-size" }}
    >
      <ColorWheel.Gradient className="absolute inset-0 block" />
      <ColorWheel.Thumb
        className="
          size-4 rounded-full border-2 border-white
          shadow-[0_0_0_1px_rgba(0,0,0,0.3),0_2px_4px_rgba(0,0,0,0.3)]
          focus-visible:shadow-[0_0_0_1px_rgba(0,0,0,0.3),0_0_0_3px_rgba(66,153,225,0.6)]
        "
        aria-label="Color"
      />
    </ColorWheel.Root>
  );
}

TIP

All components are completely unstyled — the classes above are just an example using Tailwind CSS. Use any styling approach you prefer.

Start angle offset

Use startAngle to rotate where the wheel gradient begins (in degrees):

<ColorWheel.Root
  value={color}
  onValueChange={setColor}
  colorSpace="hsl"
  startAngle={90}
  channelAngle="h"
  channelRadius="s"
>
  {/* ... */}
</ColorWheel.Root>

Different color spaces

Switch the color space and channel mapping for different wheel behaviors. For example, OKLCh:

const { color, setColor } = useColor("oklch(0.6, 0.15, 210)");

<ColorWheel.Root
  value={color}
  onValueChange={setColor}
  colorSpace="oklch"
  channelAngle="hue"
  channelRadius="chroma"
>
  {/* ... */}
</ColorWheel.Root>

Listening to changes

Use onValueChange for real-time updates (while dragging) and onValueCommit for the final value (on release):

import { Color } from "internationalized-color";

const onColorChange = (color: Color) => {
  console.log("dragging", color.toString("css"));
};
const onColorCommit = (color: Color) => {
  console.log("committed", color.toString("css"));
};

<ColorWheel.Root
  value={color}
  onValueChange={onColorChange}
  onValueCommit={onColorCommit}
  colorSpace="hsl"
  channelAngle="h"
  channelRadius="s"
>
  {/* ... */}
</ColorWheel.Root>