/ examples / bno055_webgl_demo / static / js / DDSLoader.js
DDSLoader.js
  1  /*
  2   * @author mrdoob / http://mrdoob.com/
  3   */
  4  
  5  THREE.DDSLoader = function () {
  6  	this._parser = THREE.DDSLoader.parse;
  7  };
  8  
  9  THREE.DDSLoader.prototype = Object.create( THREE.CompressedTextureLoader.prototype );
 10  THREE.DDSLoader.prototype.constructor = THREE.DDSLoader;
 11  
 12  THREE.DDSLoader.parse = function ( buffer, loadMipmaps ) {
 13  
 14  	var dds = { mipmaps: [], width: 0, height: 0, format: null, mipmapCount: 1 };
 15  
 16  	// Adapted from @toji's DDS utils
 17  	//	https://github.com/toji/webgl-texture-utils/blob/master/texture-util/dds.js
 18  
 19  	// All values and structures referenced from:
 20  	// http://msdn.microsoft.com/en-us/library/bb943991.aspx/
 21  
 22  	var DDS_MAGIC = 0x20534444;
 23  
 24  	var DDSD_CAPS = 0x1,
 25  		DDSD_HEIGHT = 0x2,
 26  		DDSD_WIDTH = 0x4,
 27  		DDSD_PITCH = 0x8,
 28  		DDSD_PIXELFORMAT = 0x1000,
 29  		DDSD_MIPMAPCOUNT = 0x20000,
 30  		DDSD_LINEARSIZE = 0x80000,
 31  		DDSD_DEPTH = 0x800000;
 32  
 33  	var DDSCAPS_COMPLEX = 0x8,
 34  		DDSCAPS_MIPMAP = 0x400000,
 35  		DDSCAPS_TEXTURE = 0x1000;
 36  
 37  	var DDSCAPS2_CUBEMAP = 0x200,
 38  		DDSCAPS2_CUBEMAP_POSITIVEX = 0x400,
 39  		DDSCAPS2_CUBEMAP_NEGATIVEX = 0x800,
 40  		DDSCAPS2_CUBEMAP_POSITIVEY = 0x1000,
 41  		DDSCAPS2_CUBEMAP_NEGATIVEY = 0x2000,
 42  		DDSCAPS2_CUBEMAP_POSITIVEZ = 0x4000,
 43  		DDSCAPS2_CUBEMAP_NEGATIVEZ = 0x8000,
 44  		DDSCAPS2_VOLUME = 0x200000;
 45  
 46  	var DDPF_ALPHAPIXELS = 0x1,
 47  		DDPF_ALPHA = 0x2,
 48  		DDPF_FOURCC = 0x4,
 49  		DDPF_RGB = 0x40,
 50  		DDPF_YUV = 0x200,
 51  		DDPF_LUMINANCE = 0x20000;
 52  
 53  	function fourCCToInt32( value ) {
 54  
 55  		return value.charCodeAt(0) +
 56  			(value.charCodeAt(1) << 8) +
 57  			(value.charCodeAt(2) << 16) +
 58  			(value.charCodeAt(3) << 24);
 59  
 60  	}
 61  
 62  	function int32ToFourCC( value ) {
 63  
 64  		return String.fromCharCode(
 65  			value & 0xff,
 66  			(value >> 8) & 0xff,
 67  			(value >> 16) & 0xff,
 68  			(value >> 24) & 0xff
 69  		);
 70  	}
 71  
 72  	function loadARGBMip( buffer, dataOffset, width, height ) {
 73  		var dataLength = width * height * 4;
 74  		var srcBuffer = new Uint8Array( buffer, dataOffset, dataLength );
 75  		var byteArray = new Uint8Array( dataLength );
 76  		var dst = 0;
 77  		var src = 0;
 78  		for ( var y = 0; y < height; y ++ ) {
 79  			for ( var x = 0; x < width; x ++ ) {
 80  				var b = srcBuffer[src]; src ++;
 81  				var g = srcBuffer[src]; src ++;
 82  				var r = srcBuffer[src]; src ++;
 83  				var a = srcBuffer[src]; src ++;
 84  				byteArray[dst] = r; dst ++;	//r
 85  				byteArray[dst] = g; dst ++;	//g
 86  				byteArray[dst] = b; dst ++;	//b
 87  				byteArray[dst] = a; dst ++;	//a
 88  			}
 89  		}
 90  		return byteArray;
 91  	}
 92  
 93  	var FOURCC_DXT1 = fourCCToInt32("DXT1");
 94  	var FOURCC_DXT3 = fourCCToInt32("DXT3");
 95  	var FOURCC_DXT5 = fourCCToInt32("DXT5");
 96  
 97  	var headerLengthInt = 31; // The header length in 32 bit ints
 98  
 99  	// Offsets into the header array
100  
101  	var off_magic = 0;
102  
103  	var off_size = 1;
104  	var off_flags = 2;
105  	var off_height = 3;
106  	var off_width = 4;
107  
108  	var off_mipmapCount = 7;
109  
110  	var off_pfFlags = 20;
111  	var off_pfFourCC = 21;
112  	var off_RGBBitCount = 22;
113  	var off_RBitMask = 23;
114  	var off_GBitMask = 24;
115  	var off_BBitMask = 25;
116  	var off_ABitMask = 26;
117  
118  	var off_caps = 27;
119  	var off_caps2 = 28;
120  	var off_caps3 = 29;
121  	var off_caps4 = 30;
122  
123  	// Parse header
124  
125  	var header = new Int32Array( buffer, 0, headerLengthInt );
126  
127  	if ( header[ off_magic ] !== DDS_MAGIC ) {
128  
129  		console.error( 'THREE.DDSLoader.parse: Invalid magic number in DDS header.' );
130  		return dds;
131  
132  	}
133  
134  	if ( ! header[ off_pfFlags ] & DDPF_FOURCC ) {
135  
136  		console.error( 'THREE.DDSLoader.parse: Unsupported format, must contain a FourCC code.' );
137  		return dds;
138  
139  	}
140  
141  	var blockBytes;
142  
143  	var fourCC = header[ off_pfFourCC ];
144  
145  	var isRGBAUncompressed = false;
146  
147  	switch ( fourCC ) {
148  
149  		case FOURCC_DXT1:
150  
151  			blockBytes = 8;
152  			dds.format = THREE.RGB_S3TC_DXT1_Format;
153  			break;
154  
155  		case FOURCC_DXT3:
156  
157  			blockBytes = 16;
158  			dds.format = THREE.RGBA_S3TC_DXT3_Format;
159  			break;
160  
161  		case FOURCC_DXT5:
162  
163  			blockBytes = 16;
164  			dds.format = THREE.RGBA_S3TC_DXT5_Format;
165  			break;
166  
167  		default:
168  
169  			if ( header[off_RGBBitCount] == 32 
170  				&& header[off_RBitMask]&0xff0000
171  				&& header[off_GBitMask]&0xff00 
172  				&& header[off_BBitMask]&0xff
173  				&& header[off_ABitMask]&0xff000000  ) {
174  				isRGBAUncompressed = true;
175  				blockBytes = 64;
176  				dds.format = THREE.RGBAFormat;
177  			} else {
178  				console.error( 'THREE.DDSLoader.parse: Unsupported FourCC code ', int32ToFourCC( fourCC ) );
179  				return dds;
180  			}
181  	}
182  
183  	dds.mipmapCount = 1;
184  
185  	if ( header[ off_flags ] & DDSD_MIPMAPCOUNT && loadMipmaps !== false ) {
186  
187  		dds.mipmapCount = Math.max( 1, header[ off_mipmapCount ] );
188  
189  	}
190  
191  	//TODO: Verify that all faces of the cubemap are present with DDSCAPS2_CUBEMAP_POSITIVEX, etc.
192  
193  	dds.isCubemap = header[ off_caps2 ] & DDSCAPS2_CUBEMAP ? true : false;
194  
195  	dds.width = header[ off_width ];
196  	dds.height = header[ off_height ];
197  
198  	var dataOffset = header[ off_size ] + 4;
199  
200  	// Extract mipmaps buffers
201  
202  	var width = dds.width;
203  	var height = dds.height;
204  
205  	var faces = dds.isCubemap ? 6 : 1;
206  
207  	for ( var face = 0; face < faces; face ++ ) {
208  
209  		for ( var i = 0; i < dds.mipmapCount; i ++ ) {
210  
211  			if ( isRGBAUncompressed ) {
212  				var byteArray = loadARGBMip( buffer, dataOffset, width, height );
213  				var dataLength = byteArray.length;
214  			} else {
215  				var dataLength = Math.max( 4, width ) / 4 * Math.max( 4, height ) / 4 * blockBytes;
216  				var byteArray = new Uint8Array( buffer, dataOffset, dataLength );
217  			}
218  			
219  			var mipmap = { "data": byteArray, "width": width, "height": height };
220  			dds.mipmaps.push( mipmap );
221  
222  			dataOffset += dataLength;
223  
224  			width = Math.max( width * 0.5, 1 );
225  			height = Math.max( height * 0.5, 1 );
226  
227  		}
228  
229  		width = dds.width;
230  		height = dds.height;
231  
232  	}
233  
234  	return dds;
235  
236  };
237