PRWM loader

examples/js/loaders/PRWMLoader.js

@@ -0,0 +1,297 @@
+/**
+ * @author Kevin Chapelier / https://github.com/kchapelier
+ * See https://github.com/kchapelier/PRWM for more informations about this file format
+ */
+
+( function ( THREE ) {
+
+	"use strict";
+
+	var bigEndianPlatform = null;
+
+	/**
+	 * Check if the endianness of the platform is big-endian (most significant bit first)
+	 * @returns {boolean} True if big-endian, false if little-endian
+	 */
+	function isBigEndianPlatform() {
+
+		if ( bigEndianPlatform === null ) {
+
+			var buffer = new ArrayBuffer( 2 ),
+				uint8Array = new Uint8Array( buffer ),
+				uint16Array = new Uint16Array( buffer );
+
+			uint8Array[ 0 ] = 0xAA; // set first byte
+			uint8Array[ 1 ] = 0xBB; // set second byte
+			bigEndianPlatform = ( uint16Array[ 0 ] === 0xAABB );
+
+		}
+
+		return bigEndianPlatform;
+
+	}
+
+	// match the values defined in the spec to the TypedArray types
+	var InvertedEncodingTypes = [
+		null,
+		Float32Array,
+		null,
+		Int8Array,
+		Int16Array,
+		null,
+		Int32Array,
+		Uint8Array,
+		Uint16Array,
+		null,
+		Uint32Array
+	];
+
+	// define the method to use on a DataView, corresponding the TypedArray type
+	var getMethods = {
+		Uint16Array: 'getUint16',
+		Uint32Array: 'getUint32',
+		Int16Array: 'getInt16',
+		Int32Array: 'getInt32',
+		Float32Array: 'getFloat32',
+		Float64Array: 'getFloat64'
+	};
+
+
+	function copyFromBuffer( sourceArrayBuffer, viewType, position, length, fromBigEndian ) {
+
+		var bytesPerElement = viewType.BYTES_PER_ELEMENT,
+			result;
+
+		if ( fromBigEndian === isBigEndianPlatform() || bytesPerElement === 1 ) {
+
+			result = new viewType( sourceArrayBuffer, position, length );
+
+		} else {
+
+			var readView = new DataView( sourceArrayBuffer, position, length * bytesPerElement ),
+				getMethod = getMethods[ viewType.name ],
+				littleEndian = ! fromBigEndian,
+				i = 0;
+
+			result = new viewType( length );
+
+			for ( ; i < length; i ++ ) {
+
+				result[ i ] = readView[ getMethod ]( i * bytesPerElement, littleEndian );
+
+			}
+
+		}
+
+		return result;
+
+	}
+
+
+	function decodePrwm( buffer ) {
+
+		var array = new Uint8Array( buffer ),
+			version = array[ 0 ],
+			flags = array[ 1 ],
+			indexedGeometry = !! ( flags >> 7 & 0x01 ),
+			indicesType = flags >> 6 & 0x01,
+			bigEndian = ( flags >> 5 & 0x01 ) === 1,
+			attributesNumber = flags & 0x1F,
+			valuesNumber = 0,
+			indicesNumber = 0;
+
+		if ( bigEndian ) {
+
+			valuesNumber = ( array[ 2 ] << 16 ) + ( array[ 3 ] << 8 ) + array[ 4 ];
+			indicesNumber = ( array[ 5 ] << 16 ) + ( array[ 6 ] << 8 ) + array[ 7 ];
+
+		} else {
+
+			valuesNumber = array[ 2 ] + ( array[ 3 ] << 8 ) + ( array[ 4 ] << 16 );
+			indicesNumber = array[ 5 ] + ( array[ 6 ] << 8 ) + ( array[ 7 ] << 16 );
+
+		}
+
+		/** PRELIMINARY CHECKS **/
+
+		if ( version === 0 ) {
+
+			throw new Error( 'PRWM decoder: Invalid format version: 0' );
+
+		} else if ( version !== 1 ) {
+
+			throw new Error( 'PRWM decoder: Unsupported format version: ' + version );
+
+		}
+
+		if ( ! indexedGeometry ) {
+
+			if ( indicesType !== 0 ) {
+
+				throw new Error( 'PRWM decoder: Indices type must be set to 0 for non-indexed geometries' );
+
+			} else if ( indicesNumber !== 0 ) {
+
+				throw new Error( 'PRWM decoder: Number of indices must be set to 0 for non-indexed geometries' );
+
+			}
+
+		}
+
+		/** PARSING **/
+
+		var pos = 8;
+
+		var attributes = {},
+			attributeName,
+			char,
+			attributeType,
+			attributeNormalized,
+			cardinality,
+			encodingType,
+			arrayType,
+			values,
+			indices,
+			i;
+
+		for ( i = 0; i < attributesNumber; i ++ ) {
+
+			attributeName = '';
+
+			while ( pos < array.length ) {
+
+				char = array[ pos ];
+				pos ++;
+
+				if ( char === 0 ) {
+
+					break;
+
+				} else {
+
+					attributeName += String.fromCharCode( char );
+
+				}
+
+			}
+
+			flags = array[ pos ];
+
+			attributeType = flags >> 7 & 0x01;
+			attributeNormalized = !! ( flags >> 6 & 0x01 );
+			cardinality = ( flags >> 4 & 0x03 ) + 1;
+			encodingType = flags & 0x0F;
+			arrayType = InvertedEncodingTypes[ encodingType ];
+
+			pos ++;
+
+			// padding to next multiple of 4
+			pos = Math.ceil( pos / 4 ) * 4;
+
+			values = copyFromBuffer( buffer, arrayType, pos, cardinality * valuesNumber, bigEndian );
+
+			pos += arrayType.BYTES_PER_ELEMENT * cardinality * valuesNumber;
+
+			attributes[ attributeName ] = {
+				type: attributeType,
+				cardinality: cardinality,
+				values: values
+			};
+
+		}
+
+		pos = Math.ceil( pos / 4 ) * 4;
+
+		indices = null;
+
+		if ( indexedGeometry ) {
+
+			indices = copyFromBuffer(
+				buffer,
+				indicesType === 1 ? Uint32Array : Uint16Array,
+				pos,
+				indicesNumber,
+				bigEndian
+			);
+
+		}
+
+		return {
+			version: version,
+			attributes: attributes,
+			indices: indices
+		};
+
+	}
+
+	// Define the public interface
+
+	THREE.PRWMLoader = function PRWMLoader( manager ) {
+
+		this.manager = ( manager !== undefined ) ? manager : THREE.DefaultLoadingManager;
+
+	};
+
+	THREE.PRWMLoader.prototype = {
+
+		constructor: THREE.PRWMLoader,
+
+		load: function ( url, onLoad, onProgress, onError ) {
+
+			var scope = this;
+
+			var loader = new THREE.FileLoader( scope.manager );
+			loader.setResponseType( 'arraybuffer' );
+
+			loader.load( url, function ( arrayBuffer ) {
+
+				onLoad( scope.parse( arrayBuffer ) );
+
+			}, onProgress, onError );
+
+		},
+
+		loadBest: function ( urlLittleEndian, urlBigEndian, onLoad, onProgress, onError ) {
+
+			this.load( ( isBigEndianPlatform() ? urlBigEndian : urlLittleEndian ), onLoad, onProgress, onError );
+
+		},
+
+		parse: function ( arrayBuffer ) {
+
+			console.time( 'PRWMLoader' );
+
+			var data = decodePrwm( arrayBuffer ),
+				attributesKey = Object.keys( data.attributes ),
+				bufferGeometry = new THREE.BufferGeometry(),
+				attribute,
+				i;
+
+			for ( i = 0; i < attributesKey.length; i ++ ) {
+
+				attribute = data.attributes[ attributesKey[ i ] ];
+				bufferGeometry.addAttribute( attributesKey[ i ], new THREE.BufferAttribute( attribute.values, attribute.cardinality, attribute.normalized ) );
+
+			}
+
+			if ( data.indices !== null ) {
+
+				bufferGeometry.setIndex( new THREE.BufferAttribute( data.indices, 1 ) );
+
+			}
+
+			console.timeEnd( 'PRWMLoader' );
+
+			return bufferGeometry;
+
+		}
+
+	};
+
+	THREE.PRWMLoader.isBigEndianPlatform = function () {
+
+		return isBigEndianPlatform();
+
+	};
+
+} )( THREE );