import THREE from 'three'

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

THREE.ShaderPass = function ( shader, textureID ) {

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

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

  this.material = new THREE.ShaderMaterial( {

          defines: shader.defines || {},
    uniforms: this.uniforms,
    vertexShader: shader.vertexShader,
    fragmentShader: shader.fragmentShader

  } );

  this.renderToScreen = false;

  this.enabled = true;
  this.needsSwap = true;
  this.clear = false;


  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.scene.add( this.quad );

};

THREE.ShaderPass.prototype = {

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

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

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

    }

    this.quad.material = this.material;

    if ( this.renderToScreen ) {

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

    } else {

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

    }

  }

};

export default THREE.ShaderPass;