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

		const oldAutoClear = renderer.autoClear;
		renderer.autoClear = false;

		this._cubeCamera.projectionMatrix.copy( this.camera.projectionMatrix );
		this._cubeCamera.quaternion.setFromRotationMatrix( this.camera.matrixWorld );

		this._cubeMesh.material.uniforms.tCube.value = this.tCube;
		this._cubeMesh.material.uniforms.tFlip.value = ( this.tCube.isCubeTexture && this.tCube.isRenderTargetTexture === false ) ? - 1 : 1;
		this._cubeMesh.material.uniforms.opacity.value = this.opacity;
		this._cubeMesh.material.transparent = ( this.opacity < 1.0 );

		renderer.setRenderTarget( this.renderToScreen ? null : readBuffer );
		if ( this.clear ) renderer.clear();
		renderer.render( this._cubeScene, this._cubeCamera );

		renderer.autoClear = oldAutoClear;

	}
Performs the cube texture pass.

@param {WebGLRenderer} renderer - The renderer.
@param {WebGLRenderTarget} writeBuffer - The write buffer. This buffer is intended as the rendering
destination for the pass.
@param {WebGLRenderTarget} readBuffer - The read buffer. The pass can access the result from the
previous pass from this buffer.
@param {number} deltaTime - The delta time in seconds.
@param {boolean} maskActive - Whether masking is active or not.