Creating Multi-Styled Lines in a React Application Using Visx
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Chapter 1: Introduction to Visx Library
The Visx library simplifies the integration of graphics into your React applications. In this guide, we will explore how to utilize Visx to create curved lines with distinct styles.
Section 1.1: Setting Up the Environment
To begin, you need to install several modules. Execute the following command to set up the necessary packages:
npm install @visx/curve @visx/gradient @visx/responsive @visx/scale @visx/shape
Section 1.2: Creating Multi-Styled Lines
Next, we will generate a chart by utilizing the components provided by the installed modules. The following code snippet demonstrates how to add a line:
import React, { useMemo } from "react";
import { scaleLinear } from "@visx/scale";
import { curveCardinal } from "@visx/curve";
import { LinePath, SplitLinePath } from "@visx/shape";
import { LinearGradient } from "@visx/gradient";
const getX = (d) => d.x;
const getY = (d) => d.y;
const background = "#045275";
const backgroundLight = "#089099";
const foreground = "#b7e6a5";
function generateSinPoints({ width, height, numberOfWaves = 10, pointsPerWave = 10 }) {
const waveLength = width / numberOfWaves;
const distanceBetweenPoints = waveLength / pointsPerWave;
const sinPoints = [];
for (let waveIndex = 0; waveIndex <= numberOfWaves; waveIndex += 1) {
const waveDistFromStart = waveIndex * waveLength;
for (let pointIndex = 0; pointIndex <= pointsPerWave; pointIndex += 1) {
const waveXFraction = pointIndex / pointsPerWave;
const waveX = pointIndex * distanceBetweenPoints;
const globalX = waveDistFromStart + waveX;
const globalXFraction = (width - globalX) / width;
const waveHeight = Math.min(globalXFraction, 1 - globalXFraction) * height;
sinPoints.push({
x: globalX,
y: waveHeight * Math.sin(waveXFraction * (2 * Math.PI))
});
}
}
return sinPoints;
}
In this code, the generateSinPoints function calculates the sine curve points based on the specified parameters.
Chapter 2: Rendering the Line
The Example component leverages the generated data to render the line with various styles.
function Example({ width, height, numberOfWaves = 10, pointsPerWave = 100, numberOfSegments = 8 }) {
const data = useMemo(() => generateSinPoints({ width, height, numberOfWaves, pointsPerWave }), [width, height, numberOfWaves, pointsPerWave]);
const dividedData = useMemo(() => {
const segmentLength = Math.floor(data.length / numberOfSegments);
return new Array(numberOfSegments).fill(null).map((_, i) => data.slice(i * segmentLength, (i + 1) * segmentLength));
}, [numberOfSegments, data]);
const getScaledX = useMemo(() => {
const xScale = scaleLinear({ range: [0, width], domain: [0, width] });
return (d) => xScale(getX(d)) ?? 0;
}, [width]);
const getScaledY = useMemo(() => {
const yScale = scaleLinear({ range: [0, height], domain: [height, 0] });
return (d) => yScale(getY(d)) ?? 0;
}, [height]);
return width < 10 ? null : (
<SplitLinePath data={dividedData}>
{({ segment, styles, index }) => (
index === numberOfSegments - 1 || index === 2 ? (
segment.map(({ x, y }, i) => (
i % 8 === 0 ? (
// Additional rendering logic can go here) : null
))
) : (
<LinePath
data={segment}
x={(d) => d.x || 0}
y={(d) => d.y || 0}
{...styles}
/>
)
)}
</SplitLinePath>
);
}
export default function App() {
return (
<Example width={800} height={400} />);
}
In this component, we establish functions to fetch x and y data points for the axes. The colors for the background gradient and line are also defined here. The generateSinPoints function is responsible for creating the sine curve points, and we utilize the Math.sin method to calculate y-axis values.
Conclusion
With the Visx library, creating lines with varying styles in your React application is straightforward and effective. If you found this tutorial helpful, consider subscribing to our YouTube channel for more insightful content!
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