three.js/examples/js/postprocessing/ClearPass.js

console.warn( "THREE.ClearPass: As part of the transition to ES6 Modules, the files in 'examples/js' were deprecated in May 2020 (r117) and will be deleted in December 2020 (r124). You can find more information about developing using ES6 Modules in https://threejs.org/docs/index.html#manual/en/introduction/Import-via-modules." );
/**
 * @author mrdoob / http://mrdoob.com/
 */

THREE.ClearPass = function ( clearColor, clearAlpha ) {

	THREE.Pass.call( this );

	this.needsSwap = false;

	this.clearColor = ( clearColor !== undefined ) ? clearColor : 0x000000;
	this.clearAlpha = ( clearAlpha !== undefined ) ? clearAlpha : 0;

};

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

	constructor: THREE.ClearPass,

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

		var oldClearColor, oldClearAlpha;

		if ( this.clearColor ) {

			oldClearColor = renderer.getClearColor().getHex();
			oldClearAlpha = renderer.getClearAlpha();

			renderer.setClearColor( this.clearColor, this.clearAlpha );

		}

		renderer.setRenderTarget( this.renderToScreen ? null : readBuffer );
		renderer.clear();

		if ( this.clearColor ) {

			renderer.setClearColor( oldClearColor, oldClearAlpha );

		}

	}

} );