File: //var/www/aspa/three/addons/loaders/RGBELoader.js
import {
	DataTextureLoader,
	DataUtils,
	FloatType,
	HalfFloatType,
	LinearFilter,
	LinearSRGBColorSpace
} from 'three';
// https://github.com/mrdoob/three.js/issues/5552
// http://en.wikipedia.org/wiki/RGBE_image_format
class RGBELoader extends DataTextureLoader {
	constructor( manager ) {
		super( manager );
		this.type = HalfFloatType;
	}
	// adapted from http://www.graphics.cornell.edu/~bjw/rgbe.html
	parse( buffer ) {
		const
			/* default error routine.  change this to change error handling */
			rgbe_read_error = 1,
			rgbe_write_error = 2,
			rgbe_format_error = 3,
			rgbe_memory_error = 4,
			rgbe_error = function ( rgbe_error_code, msg ) {
				switch ( rgbe_error_code ) {
					case rgbe_read_error: throw new Error( 'THREE.RGBELoader: Read Error: ' + ( msg || '' ) );
					case rgbe_write_error: throw new Error( 'THREE.RGBELoader: Write Error: ' + ( msg || '' ) );
					case rgbe_format_error: throw new Error( 'THREE.RGBELoader: Bad File Format: ' + ( msg || '' ) );
					default:
					case rgbe_memory_error: throw new Error( 'THREE.RGBELoader: Memory Error: ' + ( msg || '' ) );
				}
			},
			/* offsets to red, green, and blue components in a data (float) pixel */
			//RGBE_DATA_RED = 0,
			//RGBE_DATA_GREEN = 1,
			//RGBE_DATA_BLUE = 2,
			/* number of floats per pixel, use 4 since stored in rgba image format */
			//RGBE_DATA_SIZE = 4,
			/* flags indicating which fields in an rgbe_header_info are valid */
			RGBE_VALID_PROGRAMTYPE = 1,
			RGBE_VALID_FORMAT = 2,
			RGBE_VALID_DIMENSIONS = 4,
			NEWLINE = '\n',
			fgets = function ( buffer, lineLimit, consume ) {
				const chunkSize = 128;
				lineLimit = ! lineLimit ? 1024 : lineLimit;
				let p = buffer.pos,
					i = - 1, len = 0, s = '',
					chunk = String.fromCharCode.apply( null, new Uint16Array( buffer.subarray( p, p + chunkSize ) ) );
				while ( ( 0 > ( i = chunk.indexOf( NEWLINE ) ) ) && ( len < lineLimit ) && ( p < buffer.byteLength ) ) {
					s += chunk; len += chunk.length;
					p += chunkSize;
					chunk += String.fromCharCode.apply( null, new Uint16Array( buffer.subarray( p, p + chunkSize ) ) );
				}
				if ( - 1 < i ) {
					/*for (i=l-1; i>=0; i--) {
						byteCode = m.charCodeAt(i);
						if (byteCode > 0x7f && byteCode <= 0x7ff) byteLen++;
						else if (byteCode > 0x7ff && byteCode <= 0xffff) byteLen += 2;
						if (byteCode >= 0xDC00 && byteCode <= 0xDFFF) i--; //trail surrogate
					}*/
					if ( false !== consume ) buffer.pos += len + i + 1;
					return s + chunk.slice( 0, i );
				}
				return false;
			},
			/* minimal header reading.  modify if you want to parse more information */
			RGBE_ReadHeader = function ( buffer ) {
				// regexes to parse header info fields
				const magic_token_re = /^#\?(\S+)/,
					gamma_re = /^\s*GAMMA\s*=\s*(\d+(\.\d+)?)\s*$/,
					exposure_re = /^\s*EXPOSURE\s*=\s*(\d+(\.\d+)?)\s*$/,
					format_re = /^\s*FORMAT=(\S+)\s*$/,
					dimensions_re = /^\s*\-Y\s+(\d+)\s+\+X\s+(\d+)\s*$/,
					// RGBE format header struct
					header = {
						valid: 0, /* indicate which fields are valid */
						string: '', /* the actual header string */
						comments: '', /* comments found in header */
						programtype: 'RGBE', /* listed at beginning of file to identify it after "#?". defaults to "RGBE" */
						format: '', /* RGBE format, default 32-bit_rle_rgbe */
						gamma: 1.0, /* image has already been gamma corrected with given gamma. defaults to 1.0 (no correction) */
						exposure: 1.0, /* a value of 1.0 in an image corresponds to <exposure> watts/steradian/m^2. defaults to 1.0 */
						width: 0, height: 0 /* image dimensions, width/height */
					};
				let line, match;
				if ( buffer.pos >= buffer.byteLength || ! ( line = fgets( buffer ) ) ) {
					rgbe_error( rgbe_read_error, 'no header found' );
				}
				/* if you want to require the magic token then uncomment the next line */
				if ( ! ( match = line.match( magic_token_re ) ) ) {
					rgbe_error( rgbe_format_error, 'bad initial token' );
				}
				header.valid |= RGBE_VALID_PROGRAMTYPE;
				header.programtype = match[ 1 ];
				header.string += line + '\n';
				while ( true ) {
					line = fgets( buffer );
					if ( false === line ) break;
					header.string += line + '\n';
					if ( '#' === line.charAt( 0 ) ) {
						header.comments += line + '\n';
						continue; // comment line
					}
					if ( match = line.match( gamma_re ) ) {
						header.gamma = parseFloat( match[ 1 ] );
					}
					if ( match = line.match( exposure_re ) ) {
						header.exposure = parseFloat( match[ 1 ] );
					}
					if ( match = line.match( format_re ) ) {
						header.valid |= RGBE_VALID_FORMAT;
						header.format = match[ 1 ];//'32-bit_rle_rgbe';
					}
					if ( match = line.match( dimensions_re ) ) {
						header.valid |= RGBE_VALID_DIMENSIONS;
						header.height = parseInt( match[ 1 ], 10 );
						header.width = parseInt( match[ 2 ], 10 );
					}
					if ( ( header.valid & RGBE_VALID_FORMAT ) && ( header.valid & RGBE_VALID_DIMENSIONS ) ) break;
				}
				if ( ! ( header.valid & RGBE_VALID_FORMAT ) ) {
					rgbe_error( rgbe_format_error, 'missing format specifier' );
				}
				if ( ! ( header.valid & RGBE_VALID_DIMENSIONS ) ) {
					rgbe_error( rgbe_format_error, 'missing image size specifier' );
				}
				return header;
			},
			RGBE_ReadPixels_RLE = function ( buffer, w, h ) {
				const scanline_width = w;
				if (
					// run length encoding is not allowed so read flat
					( ( scanline_width < 8 ) || ( scanline_width > 0x7fff ) ) ||
					// this file is not run length encoded
					( ( 2 !== buffer[ 0 ] ) || ( 2 !== buffer[ 1 ] ) || ( buffer[ 2 ] & 0x80 ) )
				) {
					// return the flat buffer
					return new Uint8Array( buffer );
				}
				if ( scanline_width !== ( ( buffer[ 2 ] << 8 ) | buffer[ 3 ] ) ) {
					rgbe_error( rgbe_format_error, 'wrong scanline width' );
				}
				const data_rgba = new Uint8Array( 4 * w * h );
				if ( ! data_rgba.length ) {
					rgbe_error( rgbe_memory_error, 'unable to allocate buffer space' );
				}
				let offset = 0, pos = 0;
				const ptr_end = 4 * scanline_width;
				const rgbeStart = new Uint8Array( 4 );
				const scanline_buffer = new Uint8Array( ptr_end );
				let num_scanlines = h;
				// read in each successive scanline
				while ( ( num_scanlines > 0 ) && ( pos < buffer.byteLength ) ) {
					if ( pos + 4 > buffer.byteLength ) {
						rgbe_error( rgbe_read_error );
					}
					rgbeStart[ 0 ] = buffer[ pos ++ ];
					rgbeStart[ 1 ] = buffer[ pos ++ ];
					rgbeStart[ 2 ] = buffer[ pos ++ ];
					rgbeStart[ 3 ] = buffer[ pos ++ ];
					if ( ( 2 != rgbeStart[ 0 ] ) || ( 2 != rgbeStart[ 1 ] ) || ( ( ( rgbeStart[ 2 ] << 8 ) | rgbeStart[ 3 ] ) != scanline_width ) ) {
						rgbe_error( rgbe_format_error, 'bad rgbe scanline format' );
					}
					// read each of the four channels for the scanline into the buffer
					// first red, then green, then blue, then exponent
					let ptr = 0, count;
					while ( ( ptr < ptr_end ) && ( pos < buffer.byteLength ) ) {
						count = buffer[ pos ++ ];
						const isEncodedRun = count > 128;
						if ( isEncodedRun ) count -= 128;
						if ( ( 0 === count ) || ( ptr + count > ptr_end ) ) {
							rgbe_error( rgbe_format_error, 'bad scanline data' );
						}
						if ( isEncodedRun ) {
							// a (encoded) run of the same value
							const byteValue = buffer[ pos ++ ];
							for ( let i = 0; i < count; i ++ ) {
								scanline_buffer[ ptr ++ ] = byteValue;
							}
							//ptr += count;
						} else {
							// a literal-run
							scanline_buffer.set( buffer.subarray( pos, pos + count ), ptr );
							ptr += count; pos += count;
						}
					}
					// now convert data from buffer into rgba
					// first red, then green, then blue, then exponent (alpha)
					const l = scanline_width; //scanline_buffer.byteLength;
					for ( let i = 0; i < l; i ++ ) {
						let off = 0;
						data_rgba[ offset ] = scanline_buffer[ i + off ];
						off += scanline_width; //1;
						data_rgba[ offset + 1 ] = scanline_buffer[ i + off ];
						off += scanline_width; //1;
						data_rgba[ offset + 2 ] = scanline_buffer[ i + off ];
						off += scanline_width; //1;
						data_rgba[ offset + 3 ] = scanline_buffer[ i + off ];
						offset += 4;
					}
					num_scanlines --;
				}
				return data_rgba;
			};
		const RGBEByteToRGBFloat = function ( sourceArray, sourceOffset, destArray, destOffset ) {
			const e = sourceArray[ sourceOffset + 3 ];
			const scale = Math.pow( 2.0, e - 128.0 ) / 255.0;
			destArray[ destOffset + 0 ] = sourceArray[ sourceOffset + 0 ] * scale;
			destArray[ destOffset + 1 ] = sourceArray[ sourceOffset + 1 ] * scale;
			destArray[ destOffset + 2 ] = sourceArray[ sourceOffset + 2 ] * scale;
			destArray[ destOffset + 3 ] = 1;
		};
		const RGBEByteToRGBHalf = function ( sourceArray, sourceOffset, destArray, destOffset ) {
			const e = sourceArray[ sourceOffset + 3 ];
			const scale = Math.pow( 2.0, e - 128.0 ) / 255.0;
			// clamping to 65504, the maximum representable value in float16
			destArray[ destOffset + 0 ] = DataUtils.toHalfFloat( Math.min( sourceArray[ sourceOffset + 0 ] * scale, 65504 ) );
			destArray[ destOffset + 1 ] = DataUtils.toHalfFloat( Math.min( sourceArray[ sourceOffset + 1 ] * scale, 65504 ) );
			destArray[ destOffset + 2 ] = DataUtils.toHalfFloat( Math.min( sourceArray[ sourceOffset + 2 ] * scale, 65504 ) );
			destArray[ destOffset + 3 ] = DataUtils.toHalfFloat( 1 );
		};
		const byteArray = new Uint8Array( buffer );
		byteArray.pos = 0;
		const rgbe_header_info = RGBE_ReadHeader( byteArray );
		const w = rgbe_header_info.width,
			h = rgbe_header_info.height,
			image_rgba_data = RGBE_ReadPixels_RLE( byteArray.subarray( byteArray.pos ), w, h );
		let data, type;
		let numElements;
		switch ( this.type ) {
			case FloatType:
				numElements = image_rgba_data.length / 4;
				const floatArray = new Float32Array( numElements * 4 );
				for ( let j = 0; j < numElements; j ++ ) {
					RGBEByteToRGBFloat( image_rgba_data, j * 4, floatArray, j * 4 );
				}
				data = floatArray;
				type = FloatType;
				break;
			case HalfFloatType:
				numElements = image_rgba_data.length / 4;
				const halfArray = new Uint16Array( numElements * 4 );
				for ( let j = 0; j < numElements; j ++ ) {
					RGBEByteToRGBHalf( image_rgba_data, j * 4, halfArray, j * 4 );
				}
				data = halfArray;
				type = HalfFloatType;
				break;
			default:
				throw new Error( 'THREE.RGBELoader: Unsupported type: ' + this.type );
				break;
		}
		return {
			width: w, height: h,
			data: data,
			header: rgbe_header_info.string,
			gamma: rgbe_header_info.gamma,
			exposure: rgbe_header_info.exposure,
			type: type
		};
	}
	setDataType( value ) {
		this.type = value;
		return this;
	}
	load( url, onLoad, onProgress, onError ) {
		function onLoadCallback( texture, texData ) {
			switch ( texture.type ) {
				case FloatType:
				case HalfFloatType:
					texture.colorSpace = LinearSRGBColorSpace;
					texture.minFilter = LinearFilter;
					texture.magFilter = LinearFilter;
					texture.generateMipmaps = false;
					texture.flipY = true;
					break;
			}
			if ( onLoad ) onLoad( texture, texData );
		}
		return super.load( url, onLoadCallback, onProgress, onError );
	}
}
export { RGBELoader };