Class DracoEncoderExperimental

This class is subject to change.

Draco Encoder (https://google.github.io/draco/)

This class wraps the Draco encoder module.

By default, the configuration points to a copy of the Draco encoder files from the Babylon.js cdn https://cdn.babylonjs.com/draco_encoder_wasm_wrapper.js.

To update the configuration, use the following code:

    DracoEncoder.DefaultConfiguration = {
         wasmUrl: "<url to the WebAssembly library>",
         wasmBinaryUrl: "<url to the WebAssembly binary>",
         fallbackUrl: "<url to the fallback JavaScript library>",
    };
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Draco has two versions, one for WebAssembly and one for JavaScript. The encoder configuration can be set to only support WebAssembly or only support the JavaScript version. Decoding will automatically fallback to the JavaScript version if WebAssembly version is not configured or if WebAssembly is not supported by the browser. Use DracoEncoder.DefaultAvailable to determine if the encoder configuration is available for the current context.

To encode Draco compressed data, get the default DracoEncoder object and call encodeMeshAsync:

    var dracoData = await DracoEncoder.Default.encodeMeshAsync(mesh);
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Currently, DracoEncoder only encodes to meshes. Encoding to point clouds is not yet supported.

Only position, normal, color, and UV attributes are supported natively by the encoder. All other attributes are treated as generic. This means that, when decoding these generic attributes later, additional information about their original Babylon types will be needed to interpret the data correctly. You can use the return value of encodeMeshAsync to source this information, specifically the attributes field. E.g.,

   var dracoData = await DracoEncoder.Default.encodeMeshAsync(mesh);
   var meshData = await DracoDecoder.Default.decodeMeshToMeshDataAsync(dracoData.data, dracoData.attributes);
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By default, DracoEncoder will encode all available attributes of the mesh. To exclude specific attributes, use the following code:

   var options = { excludedAttributes: [VertexBuffer.MatricesIndicesKind, VertexBuffer.MatricesWeightsKind] };
   var dracoData = await DracoDecoder.Default.encodeMeshAsync(mesh, options);
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