text: /**
   * @author sunag / http://www.sunag.com.br/
   */
  
  import { TempNode } from '../core/TempNode.js';
  import { FunctionNode } from '../core/FunctionNode.js';
  import { FloatNode } from '../inputs/FloatNode.js';
  import { PositionNode } from '../accessors/PositionNode.js';
  
  function CameraNode( scope, camera ) {
  
  	TempNode.call( this, 'v3' );
  
  	this.setScope( scope || CameraNode.POSITION );
  	this.setCamera( camera );
  
  }
  
  CameraNode.Nodes = ( function () {
  
  	var depthColor = new FunctionNode( [
  		"float depthColor( float mNear, float mFar ) {",
  
  		"	#ifdef USE_LOGDEPTHBUF_EXT",
  
  		"		float depth = gl_FragDepthEXT / gl_FragCoord.w;",
  
  		"	#else",
  
  		"		float depth = gl_FragCoord.z / gl_FragCoord.w;",
  
  		"	#endif",
  
  		"	return 1.0 - smoothstep( mNear, mFar, depth );",
  
  		"}"
  	].join( "\n" ) );
  
  	return {
  		depthColor: depthColor
  	};
  
  } )();
  
  CameraNode.POSITION = 'position';
  CameraNode.DEPTH = 'depth';
  CameraNode.TO_VERTEX = 'toVertex';
  
  CameraNode.prototype = Object.create( TempNode.prototype );
  CameraNode.prototype.constructor = CameraNode;
  CameraNode.prototype.nodeType = "Camera";
  
  CameraNode.prototype.setCamera = function ( camera ) {
  
  	this.camera = camera;
  	this.updateFrame = camera !== undefined ? this.onUpdateFrame : undefined;
  
  };
  
  CameraNode.prototype.setScope = function ( scope ) {
  
  	switch ( this.scope ) {
  
  		case CameraNode.DEPTH:
  
  			delete this.near;
  			delete this.far;
  
  			break;
  
  	}
  
  	this.scope = scope;
  
  	switch ( scope ) {
  
  		case CameraNode.DEPTH:
  
  			var camera = this.camera;
  
  			this.near = new FloatNode( camera ? camera.near : 1 );
  			this.far = new FloatNode( camera ? camera.far : 1200 );
  
  			break;
  
  	}
  
  };
  
  CameraNode.prototype.getType = function ( builder ) {
  
  	switch ( this.scope ) {
  
  		case CameraNode.DEPTH:
  
  			return 'f';
  
  	}
  
  	return this.type;
  
  };
  
  CameraNode.prototype.getUnique = function ( builder ) {
  
  	switch ( this.scope ) {
  
  		case CameraNode.DEPTH:
  		case CameraNode.TO_VERTEX:
  
  			return true;
  
  	}
  
  	return false;
  
  };
  
  CameraNode.prototype.getShared = function ( builder ) {
  
  	switch ( this.scope ) {
  
  		case CameraNode.POSITION:
  
  			return false;
  
  	}
  
  	return true;
  
  };
  
  CameraNode.prototype.generate = function ( builder, output ) {
  
  	var result;
  
  	switch ( this.scope ) {
  
  		case CameraNode.POSITION:
  
  			result = 'cameraPosition';
  
  			break;
  
  		case CameraNode.DEPTH:
  
  			var depthColor = builder.include( CameraNode.Nodes.depthColor );
  
  			result = depthColor + '( ' + this.near.build( builder, 'f' ) + ', ' + this.far.build( builder, 'f' ) + ' )';
  
  			break;
  
  		case CameraNode.TO_VERTEX:
  
  			result = 'normalize( ' + new PositionNode( PositionNode.WORLD ).build( builder, 'v3' ) + ' - cameraPosition )';
  
  			break;
  
  	}
  
  	return builder.format( result, this.getType( builder ), output );
  
  };
  
  CameraNode.prototype.onUpdateFrame = function ( frame ) {
  
  	switch ( this.scope ) {
  
  		case CameraNode.DEPTH:
  
  			var camera = this.camera;
  
  			this.near.value = camera.near;
  			this.far.value = camera.far;
  
  			break;
  
  	}
  
  };
  
  CameraNode.prototype.copy = function ( source ) {
  
  	TempNode.prototype.copy.call( this, source );
  
  	this.setScope( source.scope );
  
  	if ( source.camera ) {
  
  		this.setCamera( source.camera );
  
  	}
  
  	switch ( source.scope ) {
  
  		case CameraNode.DEPTH:
  
  			this.near.number = source.near;
  			this.far.number = source.far;
  
  			break;
  
  	}
  
  };
  
  CameraNode.prototype.toJSON = function ( meta ) {
  
  	var data = this.getJSONNode( meta );
  
  	if ( ! data ) {
  
  		data = this.createJSONNode( meta );
  
  		data.scope = this.scope;
  
  		if ( this.camera ) data.camera = this.camera.uuid;
  
  		switch ( this.scope ) {
  
  			case CameraNode.DEPTH:
  
  				data.near = this.near.value;
  				data.far = this.far.value;
  
  				break;
  
  		}
  
  	}
  
  	return data;
  
  };
  
  export { CameraNode };
  