636 lines
17 KiB
JavaScript
636 lines
17 KiB
JavaScript
/**
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* @author donmccurdy / https://www.donmccurdy.com
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* @author MarkCallow / https://github.com/MarkCallow
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*
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* References:
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* - KTX: http://github.khronos.org/KTX-Specification/
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* - DFD: https://www.khronos.org/registry/DataFormat/specs/1.3/dataformat.1.3.html#basicdescriptor
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*/
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import {
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CompressedTexture,
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CompressedTextureLoader,
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FileLoader,
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LinearEncoding,
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LinearFilter,
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LinearMipmapLinearFilter,
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RGB_ETC1_Format,
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RGB_ETC2_Format,
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RGBA_ETC2_EAC_Format,
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RGB_PVRTC_4BPPV1_Format,
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RGB_S3TC_DXT1_Format,
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RGBA_ASTC_4x4_Format,
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RGBA_PVRTC_4BPPV1_Format,
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RGBA_S3TC_DXT5_Format,
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sRGBEncoding,
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UnsignedByteType,
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} from 'https://unpkg.com/three@0.114.0/build/three.module.js';
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const DFD = {
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modelUastc: 166,
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modelEtc1s: 163,
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channelUastc: {
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rgb: 0,
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rgba: 3,
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rrr: 4,
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rrrg: 5
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},
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channelEtc1s: {
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rgb: 0,
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rrr: 3,
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ggg: 4,
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aaa: 15,
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}
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};
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class KTX2Loader extends CompressedTextureLoader {
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constructor ( manager ) {
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super( manager );
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this.basisModule = null;
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this.transcoderConfig = {};
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}
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detectSupport ( renderer ) {
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this.transcoderConfig = {
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astcSupported: !! renderer.extensions.get( 'WEBGL_compressed_texture_astc' ),
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etc1Supported: !! renderer.extensions.get( 'WEBGL_compressed_texture_etc1' ),
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etc2Supported: !! renderer.extensions.get( 'WEBGL_compressed_texture_etc' ),
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dxtSupported: !! renderer.extensions.get( 'WEBGL_compressed_texture_s3tc' ),
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pvrtcSupported: !! renderer.extensions.get( 'WEBGL_compressed_texture_pvrtc' )
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|| !! renderer.extensions.get( 'WEBKIT_WEBGL_compressed_texture_pvrtc' )
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};
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return this;
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}
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init () {
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var scope = this;
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// The Emscripten wrapper returns a fake Promise, which can cause
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// infinite recursion when mixed with native Promises. Wrap the module
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// initialization to return a native Promise.
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return new Promise( function ( resolve ) {
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MSC_TRANSCODER().then( function ( basisModule ) {
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scope.basisModule = basisModule;
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basisModule.initTranscoders();
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resolve();
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} );
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} );
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}
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load ( url, onLoad, onProgress, onError ) {
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var scope = this;
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var texture = new CompressedTexture();
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var bufferPending = new Promise( function (resolve, reject ) {
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new FileLoader( scope.manager )
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.setPath( scope.path )
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.setResponseType( 'arraybuffer' )
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.load( url, resolve, onProgress, reject );
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} );
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Promise.all( [ bufferPending, this.init() ] ).then( function ( [ buffer ] ) {
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scope.parse( buffer, function ( _texture ) {
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texture.copy( _texture );
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texture.needsUpdate = true;
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if ( onLoad ) onLoad( texture );
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}, onError );
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} );
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return texture;
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}
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parse ( buffer, onLoad, onError ) {
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var BasisLzEtc1sImageTranscoder = this.basisModule.BasisLzEtc1sImageTranscoder;
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var UastcImageTranscoder = this.basisModule.UastcImageTranscoder;
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var TextureFormat = this.basisModule.TextureFormat;
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var ktx = new KTX2Container( buffer );
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// TODO(donmccurdy): Should test if texture is transcodable before attempting
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// any transcoding. If supercompressionScheme is KTX_SS_BASIS_LZ and dfd
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// colorModel is ETC1S (163) or if dfd colorModel is UASTCF (166)
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// then texture must be transcoded.
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var texFormat = ktx.dfd.colorModel == DFD.modelUastc ? TextureFormat.UASTC4x4
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: TextureFormat.ETC1S;
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// TODO(donmccurdy): Handle all channelIds (i.e. the R & R+G cases),
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// choosing appropriate transcode target formats or providing queries
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// for applications so they know what to do with the content.
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var hasAlpha = false;
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if (texFormat == TextureFormat.UASTC4x4) {
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var transcoder = new UastcImageTranscoder();
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if ( (ktx.dfd.samples[0].channelId & 0xf) === DFD.channelUastc.rgba )
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hasAlpha = true;
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} else {
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var transcoder = new BasisLzEtc1sImageTranscoder();
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if ( ktx.dfd.numSamples == 2 && (ktx.dfd.samples[1].channelId & 0xf) === DFD.channelEtc1s.aaa ) {
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hasAlpha = true;
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}
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}
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ktx.initMipmaps( texFormat, hasAlpha, transcoder, this.basisModule, this.transcoderConfig )
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.then( function () {
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var texture = new CompressedTexture(
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ktx.mipmaps,
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ktx.getWidth(),
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ktx.getHeight(),
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ktx.transcodedFormat,
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UnsignedByteType
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);
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texture.encoding = ktx.getEncoding();
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texture.premultiplyAlpha = ktx.getPremultiplyAlpha();
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texture.minFilter = ktx.mipmaps.length === 1 ? LinearFilter : LinearMipmapLinearFilter;
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texture.magFilter = LinearFilter;
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onLoad( texture );
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} )
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.catch( onError );
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return this;
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}
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}
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class KTX2Container {
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constructor ( arrayBuffer ) {
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this.arrayBuffer = arrayBuffer;
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this.mipmaps = null;
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this.transcodedFormat = null;
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// Confirm this is a KTX 2.0 file, based on the identifier in the first 12 bytes.
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var idByteLength = 12;
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var id = new Uint8Array( this.arrayBuffer, 0, idByteLength );
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if ( id[ 0 ] !== 0xAB || // '´'
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id[ 1 ] !== 0x4B || // 'K'
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id[ 2 ] !== 0x54 || // 'T'
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id[ 3 ] !== 0x58 || // 'X'
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id[ 4 ] !== 0x20 || // ' '
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id[ 5 ] !== 0x32 || // '2'
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id[ 6 ] !== 0x30 || // '0'
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id[ 7 ] !== 0xBB || // 'ª'
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id[ 8 ] !== 0x0D || // '\r'
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id[ 9 ] !== 0x0A || // '\n'
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id[ 10 ] !== 0x1A || // '\x1A'
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id[ 11 ] !== 0x0A // '\n'
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) {
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throw new Error( 'THREE.KTX2Loader: Missing KTX 2.0 identifier.' );
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}
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// TODO(donmccurdy): If we need to support BE, derive this from typeSize.
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var littleEndian = true;
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///////////////////////////////////////////////////
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// Header.
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///////////////////////////////////////////////////
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var headerByteLength = 17 * Uint32Array.BYTES_PER_ELEMENT;
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var headerReader = new KTX2BufferReader( this.arrayBuffer, idByteLength, headerByteLength, littleEndian );
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this.header = {
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vkFormat: headerReader.nextUint32(),
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typeSize: headerReader.nextUint32(),
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pixelWidth: headerReader.nextUint32(),
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pixelHeight: headerReader.nextUint32(),
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pixelDepth: headerReader.nextUint32(),
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arrayElementCount: headerReader.nextUint32(),
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faceCount: headerReader.nextUint32(),
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levelCount: headerReader.nextUint32(),
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supercompressionScheme: headerReader.nextUint32(),
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dfdByteOffset: headerReader.nextUint32(),
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dfdByteLength: headerReader.nextUint32(),
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kvdByteOffset: headerReader.nextUint32(),
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kvdByteLength: headerReader.nextUint32(),
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sgdByteOffset: headerReader.nextUint64(),
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sgdByteLength: headerReader.nextUint64(),
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};
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if ( this.header.pixelDepth > 0 ) {
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throw new Error( 'THREE.KTX2Loader: Only 2D textures are currently supported.' );
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}
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if ( this.header.arrayElementCount > 1 ) {
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throw new Error( 'THREE.KTX2Loader: Array textures are not currently supported.' );
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}
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if ( this.header.faceCount > 1 ) {
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throw new Error( 'THREE.KTX2Loader: Cube textures are not currently supported.' );
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}
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///////////////////////////////////////////////////
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// Level index
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///////////////////////////////////////////////////
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var levelByteLength = this.header.levelCount * 3 * 8;
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var levelReader = new KTX2BufferReader( this.arrayBuffer, idByteLength + headerByteLength, levelByteLength, littleEndian );
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this.levels = [];
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for ( var i = 0; i < this.header.levelCount; i ++ ) {
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this.levels.push( {
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byteOffset: levelReader.nextUint64(),
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byteLength: levelReader.nextUint64(),
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uncompressedByteLength: levelReader.nextUint64()
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} );
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}
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///////////////////////////////////////////////////
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// Data Format Descriptor (DFD)
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///////////////////////////////////////////////////
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var dfdReader = new KTX2BufferReader(
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this.arrayBuffer,
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this.header.dfdByteOffset,
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this.header.dfdByteLength,
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littleEndian
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);
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const sampleStart = 6;
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const sampleWords = 4;
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this.dfd = {
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vendorId: dfdReader.skip( 4 /* totalSize */ ).nextUint16(),
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versionNumber: dfdReader.skip( 2 /* descriptorType */ ).nextUint16(),
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descriptorBlockSize: dfdReader.nextUint16(),
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colorModel: dfdReader.nextUint8(),
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colorPrimaries: dfdReader.nextUint8(),
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transferFunction: dfdReader.nextUint8(),
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flags: dfdReader.nextUint8(),
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texelBlockDimension: {
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x: dfdReader.nextUint8() + 1,
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y: dfdReader.nextUint8() + 1,
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z: dfdReader.nextUint8() + 1,
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w: dfdReader.nextUint8() + 1,
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},
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/*
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texelBlockDimension0: dfdReader.nextUint8(),
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texelBlockDimension1: dfdReader.nextUint8(),
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texelBlockDimension2: dfdReader.nextUint8(),
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*/
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bytesPlane0: dfdReader.nextUint8(),
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numSamples: 0,
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samples: [],
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};
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dfdReader.skip( 7 /* bytesPlane[1-7] */ );
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this.dfd.numSamples = (this.dfd.descriptorBlockSize/4 - sampleStart) / sampleWords;
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for (i = 0; i < this.dfd.numSamples; i++) {
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this.dfd.samples[i] = {
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channelId: dfdReader.skip( 3 /* bitOffset + bitLength */ ).nextUint8(),
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// ... remainder not implemented.
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};
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dfdReader.skip( 12 /* samplePosition[0-3], lower, upper */ );
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}
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if ( this.header.vkFormat !== 0x00 /* VK_FORMAT_UNDEFINED */ &&
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!( this.header.supercompressionScheme === 1 /* BasisLZ */ ||
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this.dfd.colorModel === DFD.modelUastc ) ) {
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throw new Error( 'THREE.KTX2Loader: Only Basis Universal supercompression is currently supported.' );
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}
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///////////////////////////////////////////////////
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// Key/Value Data (KVD)
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///////////////////////////////////////////////////
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// Not implemented.
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this.kvd = {};
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///////////////////////////////////////////////////
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// Supercompression Global Data (SGD)
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///////////////////////////////////////////////////
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if (this.header.sgdByteLength > 0) {
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var sgdReader = new KTX2BufferReader(
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this.arrayBuffer,
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this.header.sgdByteOffset,
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this.header.sgdByteLength,
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littleEndian
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);
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this.sgd = {
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endpointCount: sgdReader.nextUint16(),
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selectorCount: sgdReader.nextUint16(),
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endpointsByteLength: sgdReader.nextUint32(),
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selectorsByteLength: sgdReader.nextUint32(),
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tablesByteLength: sgdReader.nextUint32(),
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extendedByteLength: sgdReader.nextUint32(),
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imageDescs: [],
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endpointsData: null,
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selectorsData: null,
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tablesData: null,
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extendedData: null,
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};
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for ( var i = 0; i < this.header.levelCount; i ++ ) {
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this.sgd.imageDescs.push( {
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imageFlags: sgdReader.nextUint32(),
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rgbSliceByteOffset: sgdReader.nextUint32(),
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rgbSliceByteLength: sgdReader.nextUint32(),
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alphaSliceByteOffset: sgdReader.nextUint32(),
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alphaSliceByteLength: sgdReader.nextUint32(),
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} );
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}
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var endpointsByteOffset = this.header.sgdByteOffset + sgdReader.offset;
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var selectorsByteOffset = endpointsByteOffset + this.sgd.endpointsByteLength;
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var tablesByteOffset = selectorsByteOffset + this.sgd.selectorsByteLength;
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var extendedByteOffset = tablesByteOffset + this.sgd.tablesByteLength;
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this.sgd.endpointsData = new Uint8Array( this.arrayBuffer, endpointsByteOffset, this.sgd.endpointsByteLength );
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this.sgd.selectorsData = new Uint8Array( this.arrayBuffer, selectorsByteOffset, this.sgd.selectorsByteLength );
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this.sgd.tablesData = new Uint8Array( this.arrayBuffer, tablesByteOffset, this.sgd.tablesByteLength );
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this.sgd.extendedData = new Uint8Array( this.arrayBuffer, extendedByteOffset, this.sgd.extendedByteLength );
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} else {
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this.sgd = {};
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}
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}
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initMipmaps ( texFormat, hasAlpha, transcoder, basisModule, config ) {
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var TranscodeTarget = basisModule.TranscodeTarget;
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var TextureFormat = basisModule.TextureFormat;
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var ImageInfo = basisModule.ImageInfo;
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var scope = this;
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var mipmaps = [];
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var width = this.getWidth();
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var height = this.getHeight();
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var isVideo = false;
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// For both ETC1S and UASTC4x4 formats.
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if ( texFormat == TextureFormat.ETC1S ) {
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var numEndpoints = this.sgd.endpointCount;
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var numSelectors = this.sgd.selectorCount;
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var endpoints = this.sgd.endpointsData;
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var selectors = this.sgd.selectorsData;
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var tables = this.sgd.tablesData;
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transcoder.decodePalettes( numEndpoints, endpoints, numSelectors, selectors );
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transcoder.decodeTables( tables );
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}
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var targetFormat;
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if ( config.astcSupported ) {
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targetFormat = TranscodeTarget.ASTC_4x4_RGBA;
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this.transcodedFormat = RGBA_ASTC_4x4_Format;
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} else if ( config.dxtSupported ) {
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targetFormat = hasAlpha ? TranscodeTarget.BC3_RGBA : TranscodeTarget.BC1_RGB;
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this.transcodedFormat = hasAlpha ? RGBA_S3TC_DXT5_Format : RGB_S3TC_DXT1_Format;
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} else if ( config.pvrtcSupported ) {
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targetFormat = hasAlpha ? TranscodeTarget.PVRTC1_4_RGBA : TranscodeTarget.PVRTC1_4_RGB;
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this.transcodedFormat = hasAlpha ? RGBA_PVRTC_4BPPV1_Format : RGB_PVRTC_4BPPV1_Format;
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} else if ( config.etc2Supported ) {
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targetFormat = hasAlpha ? TranscodeTarget.ETC2_RGBA : TranscodeTarget.ETC1_RGB /* subset of ETC2 */;
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this.transcodedFormat = hasAlpha ? RGBA_ETC2_EAC_Format : RGB_ETC2_Format;
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} else if ( config.etc1Supported ) {
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targetFormat = TranscodeTarget.ETC1_RGB;
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this.transcodedFormat = RGB_ETC1_Format;
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} else {
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throw new Error( 'THREE.KTX2Loader: No suitable compressed texture format found.' );
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}
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if ( !basisModule.isFormatSupported( targetFormat, texFormat ) ) {
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throw new Error( 'THREE.KTX2Loader: Selected texture format not supported by current msc_basis_transcoder.js build.' );
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}
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var imageDescIndex = 0;
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for ( var level = 0; level < this.header.levelCount; level ++ ) {
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var levelWidth = width / Math.pow( 2, level );
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var levelHeight = height / Math.pow( 2, level );
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var numImagesInLevel = 1; // TODO(donmccurdy): Support cubemaps, arrays and 3D.
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var imageOffsetInLevel = 0;
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var imageInfo = new ImageInfo(texFormat, levelWidth, levelHeight, level);
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var levelImageByteLength = imageInfo.numBlocksX * imageInfo.numBlocksY * this.dfd.bytesPlane0;
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for ( var imageIndex = 0; imageIndex < numImagesInLevel; imageIndex ++ ) {
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var result;
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if ( texFormat == TextureFormat.UASTC4x4 ) {
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imageInfo.flags = 0;
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imageInfo.rgbByteOffset = 0;
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imageInfo.rgbByteLength = levelImageByteLength;
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imageInfo.alphaByteOffset = 0;
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imageInfo.alphaByteLength = 0;
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result = transcoder.transcodeImage(targetFormat,
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new Uint8Array( this.arrayBuffer, this.levels[ level ].byteOffset + imageOffsetInLevel, levelImageByteLength),
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imageInfo,
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0,
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hasAlpha,
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isVideo
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);
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} else {
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var imageDesc = this.sgd.imageDescs[ imageDescIndex++ ];
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imageInfo.flags = imageDesc.imageFlags;
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imageInfo.rgbByteOffset = 0;
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imageInfo.rgbByteLength = imageDesc.rgbSliceByteLength;
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imageInfo.alphaByteOffset = imageDesc.alphaSliceByteOffset > 0 ? imageDesc.rgbSliceByteLength : 0;
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imageInfo.alphaByteLength = imageDesc.alphaSliceByteLength;
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result = transcoder.transcodeImage(targetFormat,
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new Uint8Array( this.arrayBuffer, this.levels[ level ].byteOffset + imageDesc.rgbSliceByteOffset, imageDesc.rgbSliceByteLength + imageDesc.alphaSliceByteLength ),
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imageInfo,
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0,
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isVideo
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);
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}
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if ( result.transcodedImage === undefined ) {
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throw new Error( 'THREE.KTX2Loader: Unable to transcode image.' );
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}
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// Transcoded image is written in memory allocated by WASM. We could avoid copying
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// the image by waiting until the image is uploaded to the GPU, then calling
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// delete(). However, (1) we don't know if the user will later need to re-upload it
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||
// e.g. after calling texture.clone(), and (2) this code will eventually be in a
|
||
// Web Worker, and transferring WASM's memory seems like a very bad idea.
|
||
var levelData = result.transcodedImage.get_typed_memory_view().slice();
|
||
result.transcodedImage.delete();
|
||
|
||
mipmaps.push( { data: levelData, width: levelWidth, height: levelHeight } );
|
||
imageOffsetInLevel += levelImageByteLength;
|
||
|
||
}
|
||
|
||
}
|
||
|
||
return new Promise( function ( resolve, reject ) {
|
||
|
||
scope.mipmaps = mipmaps;
|
||
|
||
resolve();
|
||
|
||
} );
|
||
|
||
}
|
||
|
||
getWidth () { return this.header.pixelWidth; }
|
||
|
||
getHeight () { return this.header.pixelHeight; }
|
||
|
||
getEncoding () {
|
||
|
||
return this.dfd.transferFunction === 2 /* KHR_DF_TRANSFER_SRGB */
|
||
? sRGBEncoding
|
||
: LinearEncoding;
|
||
|
||
}
|
||
|
||
getPremultiplyAlpha () {
|
||
|
||
return !! ( this.dfd.flags & 1 /* KHR_DF_FLAG_ALPHA_PREMULTIPLIED */ );
|
||
|
||
}
|
||
|
||
}
|
||
|
||
class KTX2BufferReader {
|
||
|
||
constructor ( arrayBuffer, byteOffset, byteLength, littleEndian ) {
|
||
|
||
this.dataView = new DataView( arrayBuffer, byteOffset, byteLength );
|
||
this.littleEndian = littleEndian;
|
||
this.offset = 0;
|
||
|
||
}
|
||
|
||
nextUint8 () {
|
||
|
||
var value = this.dataView.getUint8( this.offset, this.littleEndian );
|
||
|
||
this.offset += 1;
|
||
|
||
return value;
|
||
|
||
}
|
||
|
||
nextUint16 () {
|
||
|
||
var value = this.dataView.getUint16( this.offset, this.littleEndian );
|
||
|
||
this.offset += 2;
|
||
|
||
return value;
|
||
|
||
}
|
||
|
||
nextUint32 () {
|
||
|
||
var value = this.dataView.getUint32( this.offset, this.littleEndian );
|
||
|
||
this.offset += 4;
|
||
|
||
return value;
|
||
|
||
}
|
||
|
||
nextUint64 () {
|
||
|
||
// https://stackoverflow.com/questions/53103695/
|
||
var left = this.dataView.getUint32( this.offset, this.littleEndian );
|
||
var right = this.dataView.getUint32( this.offset + 4, this.littleEndian );
|
||
var value = this.littleEndian ? left + ( 2 ** 32 * right ) : ( 2 ** 32 * left ) + right;
|
||
|
||
if ( ! Number.isSafeInteger( value ) ) {
|
||
|
||
console.warn( 'THREE.KTX2Loader: ' + value + ' exceeds MAX_SAFE_INTEGER. Precision may be lost.' );
|
||
|
||
}
|
||
|
||
this.offset += 8;
|
||
|
||
return value;
|
||
|
||
}
|
||
|
||
skip ( bytes ) {
|
||
|
||
this.offset += bytes;
|
||
|
||
return this;
|
||
|
||
}
|
||
|
||
}
|
||
|
||
export { KTX2Loader };
|