@gltf-transform/functions/dist/quantize.d.ts

Functions for common glTF modifications, written using the core API

import { Transform } from '@gltf-transform/core';
/** Options for the {@link quantize} function. */
export interface QuantizeOptions {
    /** Pattern (regex) used to filter vertex attribute semantics for quantization. Default: all. */
    pattern?: RegExp;
    /** Pattern (regex) used to filter morph target semantics for quantization. Default: `options.pattern`. */
    patternTargets?: RegExp;
    /** Bounds for quantization grid. */
    quantizationVolume?: 'mesh' | 'scene';
    /** Quantization bits for `POSITION` attributes. */
    quantizePosition?: number;
    /** Quantization bits for `NORMAL` attributes. */
    quantizeNormal?: number;
    /** Quantization bits for `TEXCOORD_*` attributes. */
    quantizeTexcoord?: number;
    /** Quantization bits for `COLOR_*` attributes. */
    quantizeColor?: number;
    /** Quantization bits for `WEIGHT_*` attributes. */
    quantizeWeight?: number;
    /** Quantization bits for application-specific (`_*`) attributes. */
    quantizeGeneric?: number;
    /** Normalize weight attributes. */
    normalizeWeights?: boolean;
    /**
     * Whether to perform cleanup steps after completing the operation. Recommended, and enabled by
     * default. Cleanup removes temporary resources created during the operation, but may also remove
     * pre-existing unused or duplicate resources in the {@link Document}. Applications that require
     * keeping these resources may need to disable cleanup, instead calling {@link dedup} and
     * {@link prune} manually (with customized options) later in the processing pipeline.
     * @experimental
     */
    cleanup?: boolean;
}
export declare const QUANTIZE_DEFAULTS: Required<Omit<QuantizeOptions, 'patternTargets'>>;
/**
 * References:
 * - https://github.com/KhronosGroup/glTF/tree/master/extensions/2.0/Khronos/KHR_mesh_quantization
 * - http://www.aclockworkberry.com/normal-unpacking-quantization-errors/
 * - https://www.mathworks.com/help/dsp/ref/uniformencoder.html
 * - https://oroboro.com/compressed-unit-vectors/
 */
/**
 * Quantizes vertex attributes with `KHR_mesh_quantization`, reducing the size and memory footprint
 * of the file. Conceptually, quantization refers to snapping values to regular intervals; vertex
 * positions are snapped to a 3D grid, UVs to a 2D grid, and so on. When quantized to <= 16 bits,
 * larger component types may be more compactly stored as 16-bit or 8-bit attributes.
 *
 * Often, it can be useful to quantize to precision lower than the maximum allowed by the component
 * type. Positions quantized to 14 bits in a 16-bit accessor will occupy 16 bits in VRAM, but they
 * can be compressed further for network compression with lossless encodings such as ZSTD.
 *
 * Vertex positions are shifted into [-1,1] or [0,1] range before quantization. Compensating for
 * that shift, a transform is applied to the parent {@link Node}, or inverse bind matrices for a
 * {@link Skin} if applicable. Materials using {@link KHRMaterialsVolume} are adjusted to maintain
 * appearance. In future releases, UVs may also be transformed with {@link KHRTextureTransform}.
 * Currently UVs outside of [0,1] range are not quantized.
 *
 * In most cases, quantization requires {@link KHRMeshQuantization}; the extension will be added
 * automatically when `quantize()` is applied. When applying meshopt compression with
 * {@link EXTMeshoptCompression}, quantization is usually applied before compression.
 *
 * Example:
 *
 * ```javascript
 * import { quantize } from '@gltf-transform/functions';
 *
 * await document.transform(
 *   quantize({
 *		quantizePosition: 14,
 *		quantizeNormal: 10,
 *   }),
 * );
 * ```
 *
 * For the inverse operation, see {@link dequantize}.
 *
 * @category Transforms
 */
export declare function quantize(_options?: QuantizeOptions): Transform;