constructor(resolution, scene, camera) {
            super();
            this.renderScene = scene;
            this.camera = camera;
            this.resolution = new Vector2(resolution.x, resolution.y);
            // @ts-ignore
            this.fsQuad = new FullScreenQuad(null);
            this.fsQuad.material = this.createOutlinePostProcessMaterial();
            // Create a buffer to store the normals of the scene onto
            const normalTarget = new WebGLRenderTarget(this.resolution.x, this.resolution.y);
            normalTarget.texture.format = RGBAFormat;
            normalTarget.texture.minFilter = NearestFilter;
            normalTarget.texture.magFilter = NearestFilter;
            normalTarget.texture.generateMipmaps = false;
            normalTarget.stencilBuffer = false;
            this.normalTarget = normalTarget;
            this.normalOverrideMaterial = new MeshNormalMaterial();
        }
NVIDIA FXAA by Timothy Lottes
http://timothylottes.blogspot.com/2011/06/fxaa3-source-released.html
- WebGL port by @supereggbert
http://www.glge.org/demos/fxaa/