three.js/examples/js/shaders/nodes/BuilderNode.js

/**
 * @author sunag / http://www.sunag.com.br/
 */

THREE.BuilderNode = function( material ) {

	this.material = material;

	this.require = {};
	this.isVerify = false;
	this.cache = '';

};

THREE.BuilderNode.prototype = {
	constructor: THREE.BuilderNode,

	include : function( func ) {

		this.material.include( this.shader, func );

	},

	getFormatConstructor : function( len ) {

		return THREE.BuilderNode.constructors[ len - 1 ];

	},

	getFormat : function( format ) {

		return format.replace( 'c', 'v3' ).replace( /fv1|iv1/, 'v1' );

	},

	getFormatLength : function( format ) {

		return parseInt( this.getFormat( format ).substr( 1 ) );

	},

	getFormatByLength : function( len ) {

		if ( len == 1 ) return 'fv1';

		return 'v' + len;

	},

	format : function( code, from, to ) {

		var format = this.getFormat( from + '=' + to );

		switch ( format ) {
			case 'v1=v2': return 'vec2(' + code + ')';
			case 'v1=v3': return 'vec3(' + code + ')';
			case 'v1=v4': return 'vec4(' + code + ')';

			case 'v2=v1': return code + '.x';
			case 'v2=v3': return 'vec3(' + code + ',0.0)';
			case 'v2=v4': return 'vec4(' + code + ',0.0,0.0)';

			case 'v3=v1': return code + '.x';
			case 'v3=v2': return code + '.xy';
			case 'v3=v4': return 'vec4(' + code + ',0.0)';

			case 'v4=v1': return code + '.x';
			case 'v4=v2': return code + '.xy';
			case 'v4=v3': return code + '.xyz';
		}

		return code;

	},

	getType : function( format ) {

		return THREE.BuilderNode.type[ format ];

	},

	getUuid : function( uuid, useCache ) {

		useCache = useCache !== undefined ? useCache : true;

		if ( useCache && this.cache ) uuid = this.cache + '-' + uuid;

		return uuid;

	},

	setCache : function( name ) {

		this.cache = name || '';

		return this;

	},

	getElementByIndex : function( index ) {

		return THREE.BuilderNode.elements[ index ];

	},

	getElementIndex : function( elm ) {

		return THREE.BuilderNode.elements.indexOf( elm );

	},

	isShader : function( shader ) {

		return this.shader == shader || this.isVerify;

	},

	setShader : function( shader ) {

		this.shader = shader;

		return this;

	}
};

THREE.BuilderNode.type = {
	'float' : 'fv1',
	vec2 : 'v2',
	vec3 : 'v3',
	vec4 : 'v4'
};

THREE.BuilderNode.constructors = [
	'',
	'vec2',
	'vec3',
	'vec4'
];

THREE.BuilderNode.elements = [
	'x',
	'y',
	'z',
	'w'
];