three
Version:
JavaScript 3D library
191 lines (134 loc) • 4.18 kB
JavaScript
import {
Loader,
TextureLoader,
Data3DTexture,
RGBAFormat,
UnsignedByteType,
ClampToEdgeWrapping,
LinearFilter,
} from 'three';
/**
* A loader for loading LUT images.
*
* ```js
* const loader = new LUTImageLoader();
* const map = loader.loadAsync( 'luts/NeutralLUT.png' );
* ```
*
* @augments Loader
* @three_import import { LUTImageLoader } from 'three/addons/loaders/LUTImageLoader.js';
*/
export class LUTImageLoader extends Loader {
/**
* Constructs a new LUT loader.
*
* @param {LoadingManager} [manager] - The loading manager.
*/
constructor( manager ) {
super( manager );
/**
* Whether to vertically flip the LUT or not.
*
* Depending on the LUT's origin, the texture has green at the bottom (e.g. for Unreal)
* or green at the top (e.g. for Unity URP Color Lookup). If you're using lut image strips
* from a Unity pipeline, then set this property to `true`.
*
* @type {boolean}
* @default false
*/
this.flip = false;
}
/**
* Starts loading from the given URL and passes the loaded LUT
* to the `onLoad()` callback.
*
* @param {string} url - The path/URL of the file to be loaded. This can also be a data URI.
* @param {function({size:number,texture3D:Data3DTexture})} onLoad - Executed when the loading process has been finished.
* @param {onProgressCallback} onProgress - Executed while the loading is in progress.
* @param {onErrorCallback} onError - Executed when errors occur.
*/
load( url, onLoad, onProgress, onError ) {
const loader = new TextureLoader( this.manager );
loader.setCrossOrigin( this.crossOrigin );
loader.setPath( this.path );
loader.load( url, texture => {
try {
let imageData;
if ( texture.image.width < texture.image.height ) {
imageData = this._getImageData( texture );
} else {
imageData = this._horz2Vert( texture );
}
onLoad( this.parse( imageData.data, Math.min( texture.image.width, texture.image.height ) ) );
} catch ( e ) {
if ( onError ) {
onError( e );
} else {
console.error( e );
}
this.manager.itemError( url );
}
}, onProgress, onError );
}
/**
* Parses the given LUT data and returns the resulting 3D data texture.
*
* @param {Uint8ClampedArray} dataArray - The raw LUT data.
* @param {number} size - The LUT size.
* @return {{size:number,texture3D:Data3DTexture}} An object representing the parsed LUT.
*/
parse( dataArray, size ) {
const data = new Uint8Array( dataArray );
const texture3D = new Data3DTexture();
texture3D.image.data = data;
texture3D.image.width = size;
texture3D.image.height = size;
texture3D.image.depth = size;
texture3D.format = RGBAFormat;
texture3D.type = UnsignedByteType;
texture3D.magFilter = LinearFilter;
texture3D.minFilter = LinearFilter;
texture3D.wrapS = ClampToEdgeWrapping;
texture3D.wrapT = ClampToEdgeWrapping;
texture3D.wrapR = ClampToEdgeWrapping;
texture3D.generateMipmaps = false;
texture3D.needsUpdate = true;
return {
size,
texture3D,
};
}
// internal
_getImageData( texture ) {
const width = texture.image.width;
const height = texture.image.height;
const canvas = document.createElement( 'canvas' );
canvas.width = width;
canvas.height = height;
const context = canvas.getContext( '2d' );
if ( this.flip === true ) {
context.scale( 1, - 1 );
context.translate( 0, - height );
}
context.drawImage( texture.image, 0, 0 );
return context.getImageData( 0, 0, width, height );
}
_horz2Vert( texture ) {
const width = texture.image.height;
const height = texture.image.width;
const canvas = document.createElement( 'canvas' );
canvas.width = width;
canvas.height = height;
const context = canvas.getContext( '2d' );
if ( this.flip === true ) {
context.scale( 1, - 1 );
context.translate( 0, - height );
}
for ( let i = 0; i < width; i ++ ) {
const sy = i * width;
const dy = ( this.flip ) ? height - i * width : i * width;
context.drawImage( texture.image, sy, 0, width, width, 0, dy, width, width );
}
return context.getImageData( 0, 0, width, height );
}
}