README

react-shader-canvas

A react component to display and control a WebGL shader.

Introduction

Sometimes you want a simple way of displaying a WebGL Shader within your React project without a large 3D library like three.js, Alfrid or Babylon.js. This component does exactly that! You can very easily specify the size, shaders and optional uniforms to pass into the shader.

This project is essentially a wrapper around glslCanvas that allows it to be used within your React projects. Please check out their documentation to see whats happening under the hood.

Installation

Install this package with npm.

npm i @signal-noise/react-shader-canvas

Usage

Here is the most minimal example...

import React from 'react';
import ShaderCanvas from "@signal-noise/react-shader-canvas";

const shader = `
  precision mediump float;
  void main() {
    gl_FragColor = vec4(1, 0, 0, 1);
  }
`;

const RedView = () => (
  <ShaderCanvas width={320} height={240} fragShader={shader} />
);

You can optionally pass in a vertex shader, uniforms and a supersample value.

import React from 'react';
import ShaderCanvas from "@signal-noise/react-shader-canvas";

// Using the webpack loader "shader-loader"
import fragShader from "./noise.frag";
import vertShader from "./noise.vert";

const FunkyView = () => {

  // Uniforms to pass into the shader
  const uniforms = {
    u_color_bg: [11, 12, 33],
    u_color_noise: [205, 255, 0],
    u_noise_amount: 0.5
  };

  return (
    <ShaderCanvas
      width={640}
      height={480}
      fragShader={fragShader}
      vertShader={vertShader}
      uniforms={uniforms}
      superSample={2} // Render twice the display resolution
    />
  );
};

API

width : Required - Number - The width in pixels.
height : Required - Number - The height in pixels.
fragShader : Required - String - The fragment shader to use.
vertShader : Optional - String - The vertex shader to use.
uniforms : Optional - Object - An object containing vec2, vec3 and float key value pairs.
superSample : Optional - Number - A value to supersample by, creating a smoother image.

Notes

Super Sampling

You have the option of super sampling as a method to antialias the final output. A value of 2 is generally a good idea. This quadruples the processing requirements.

Retina

The rendered output matches the devices pixel density automatically.

Mouse

A vec2 uniform u_mouse is passed into the shader.

Usage no npm install needed!