Accueil / npm / three@0.186.1 / examples / jsm / tsl / display / Lut3DNode.js
Lut3DNode.js
import { TempNode } from 'three/webgpu';
import { nodeObject, Fn, float, uniform, vec3, vec4, mix } from 'three/tsl';
/**
* A post processing node for color grading via lookup tables.
*
* @augments TempNode
* @three_import import { lut3D } from 'three/addons/tsl/display/Lut3DNode.js';
*/
class Lut3DNode extends TempNode {
static get type() {
return 'Lut3DNode';
}
/**
* Constructs a new LUT node.
*
* @param {Node} inputNode - The node that represents the input of the effect.
* @param {TextureNode} lutNode - A texture node that represents the lookup table.
* @param {number} size - The size of the lookup table.
* @param {Node<float>} intensityNode - Controls the intensity of the effect.
*/
constructor( inputNode, lutNode, size, intensityNode ) {
super( 'vec4' );
/**
* The node that represents the input of the effect.
*
* @type {Node}
*/
this.inputNode = inputNode;
/**
* A texture node that represents the lookup table.
*
* @type {TextureNode}
*/
this.lutNode = lutNode;
/**
* The size of the lookup table.
*
* @type {UniformNode<float>}
*/
this.size = uniform( size );
/**
* Controls the intensity of the effect.
*
* @type {Node<float>}
*/
this.intensityNode = intensityNode;
}
/**
* This method is used to setup the effect's TSL code.
*
* @param {NodeBuilder} builder - The current node builder.
* @return {ShaderCallNodeInternal}
*/
setup() {
const { inputNode, lutNode } = this;
const sampleLut = ( uv ) => lutNode.sample( uv );
const lut3D = Fn( () => {
const base = inputNode;
// pull the sample in by half a pixel so the sample begins at the center of the edge pixels.
const pixelWidth = float( 1.0 ).div( this.size );
const halfPixelWidth = float( 0.5 ).div( this.size );
const uvw = vec3( halfPixelWidth ).add( base.rgb.mul( float( 1.0 ).sub( pixelWidth ) ) );
const lutValue = vec4( sampleLut( uvw ).rgb, base.a );
return vec4( mix( base, lutValue, this.intensityNode ) );
} );
const outputNode = lut3D();
return outputNode;
}
}
export default Lut3DNode;
/**
* TSL function for creating a LUT node for color grading via post processing.
*
* @tsl
* @function
* @param {Node} node - The node that represents the input of the effect.
* @param {TextureNode} lut - A texture node that represents the lookup table.
* @param {number} size - The size of the lookup table.
* @param {Node<float> | number} intensity - Controls the intensity of the effect.
* @returns {Lut3DNode}
*/
export const lut3D = ( node, lut, size, intensity ) => new Lut3DNode( nodeObject( node ), nodeObject( lut ), size, nodeObject( intensity ) );