three.js/examples/js/postprocessing/DotScreenPass.js

THREE.DotScreenPass = function ( center, angle, scale ) {

	THREE.Pass.call( this );

	if ( THREE.DotScreenShader === undefined )
		console.error( 'THREE.DotScreenPass relies on THREE.DotScreenShader' );

	var shader = THREE.DotScreenShader;

	this.uniforms = THREE.UniformsUtils.clone( shader.uniforms );

	if ( center !== undefined ) this.uniforms[ 'center' ].value.copy( center );
	if ( angle !== undefined ) this.uniforms[ 'angle' ].value = angle;
	if ( scale !== undefined ) this.uniforms[ 'scale' ].value = scale;

	this.material = new THREE.ShaderMaterial( {

		uniforms: this.uniforms,
		vertexShader: shader.vertexShader,
		fragmentShader: shader.fragmentShader

	} );

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

};

THREE.DotScreenPass.prototype = Object.assign( Object.create( THREE.Pass.prototype ), {

	constructor: THREE.DotScreenPass,

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

		this.uniforms[ 'tDiffuse' ].value = readBuffer.texture;
		this.uniforms[ 'tSize' ].value.set( readBuffer.width, readBuffer.height );

		if ( this.renderToScreen ) {

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

		} else {

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

		}

	}

} );