three.js/examples/jsm/postprocessing/HalftonePass.js

import {
	ShaderMaterial,
	UniformsUtils
} from '../../../build/three.module.js';
import { Pass } from '../postprocessing/Pass.js';
import { HalftoneShader } from '../shaders/HalftoneShader.js';

/**
 * RGB Halftone pass for three.js effects composer. Requires HalftoneShader.
 */

var HalftonePass = function ( width, height, params ) {

	Pass.call( this );

 	if ( HalftoneShader === undefined ) {

 		console.error( 'THREE.HalftonePass requires HalftoneShader' );

 	}

 	this.uniforms = UniformsUtils.clone( HalftoneShader.uniforms );
 	this.material = new ShaderMaterial( {
 		uniforms: this.uniforms,
 		fragmentShader: HalftoneShader.fragmentShader,
 		vertexShader: HalftoneShader.vertexShader
 	} );

	// set params
	this.uniforms.width.value = width;
	this.uniforms.height.value = height;

	for ( var key in params ) {

		if ( params.hasOwnProperty( key ) && this.uniforms.hasOwnProperty( key ) ) {

			this.uniforms[ key ].value = params[ key ];

		}

	}

	this.fsQuad = new Pass.FullScreenQuad( this.material );

};

HalftonePass.prototype = Object.assign( Object.create( Pass.prototype ), {

	constructor: HalftonePass,

	render: function ( renderer, writeBuffer, readBuffer/*, deltaTime, maskActive*/ ) {

 		this.material.uniforms[ 'tDiffuse' ].value = readBuffer.texture;

 		if ( this.renderToScreen ) {

 			renderer.setRenderTarget( null );
 			this.fsQuad.render( renderer );

		} else {

 			renderer.setRenderTarget( writeBuffer );
 			if ( this.clear ) renderer.clear();
			this.fsQuad.render( renderer );

		}

 	},

 	setSize: function ( width, height ) {

 		this.uniforms.width.value = width;
 		this.uniforms.height.value = height;

 	}
} );

export { HalftonePass };