/**
 * @author alteredq / http://alteredqualia.com/
 */

THREE.ShaderPass = function (shader, textureID) {

    THREE.Pass.call(this);

    this.textureID = (textureID !== undefined) ? textureID : "tDiffuse";

    if (shader instanceof THREE.ShaderMaterial) {

        this.uniforms = shader.uniforms;

        this.material = shader;

    } else if (shader) {

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

        this.material = new THREE.ShaderMaterial({

            defines: Object.assign({}, shader.defines),
            uniforms: this.uniforms,
            vertexShader: shader.vertexShader,
            fragmentShader: shader.fragmentShader

        });

    }

    this.camera = new THREE.OrthographicCamera(-1, 1, 1, -1, 0, 1);
    this.scene = new THREE.Scene();

    this.quad = new THREE.Mesh(new THREE.PlaneBufferGeometry(2, 2), null);
    this.quad.frustumCulled = false; // Avoid getting clipped
    this.scene.add(this.quad);

};

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

    constructor: THREE.ShaderPass,

    render: function (renderer, writeBuffer, readBuffer, delta, maskActive) {

        if (this.uniforms[this.textureID]) {

            this.uniforms[this.textureID].value = readBuffer.texture;

        }

        this.quad.material = this.material;

        if (this.renderToScreen) {

            renderer.render(this.scene, this.camera);

        } else {

            renderer.render(this.scene, this.camera, writeBuffer, this.clear);

        }

    }

});