55 lines
1.4 KiB
JavaScript
55 lines
1.4 KiB
JavaScript
/**
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* Utility class for generating a flakes texture image. This image might be used
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* as a normal map to produce a car paint like effect.
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*
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* @three_import import { FlakesTexture } from 'three/addons/textures/FlakesTexture.js';
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*/
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class FlakesTexture {
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/**
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* Generates a new flakes texture image. The result is a canvas
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* that can be used as an input for {@link CanvasTexture}.
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*
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* @param {number} [width=512] - The width of the image.
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* @param {number} [height=512] - The height of the image.
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* @return {HTMLCanvasElement} The generated image.
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*/
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constructor( width = 512, height = 512 ) {
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const canvas = document.createElement( 'canvas' );
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canvas.width = width;
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canvas.height = height;
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const context = canvas.getContext( '2d' );
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context.fillStyle = 'rgb(127,127,255)';
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context.fillRect( 0, 0, width, height );
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for ( let i = 0; i < 4000; i ++ ) {
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const x = Math.random() * width;
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const y = Math.random() * height;
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const r = Math.random() * 3 + 3;
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let nx = Math.random() * 2 - 1;
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let ny = Math.random() * 2 - 1;
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let nz = 1.5;
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const l = Math.sqrt( nx * nx + ny * ny + nz * nz );
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nx /= l; ny /= l; nz /= l;
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context.fillStyle = 'rgb(' + ( nx * 127 + 127 ) + ',' + ( ny * 127 + 127 ) + ',' + ( nz * 255 ) + ')';
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context.beginPath();
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context.arc( x, y, r, 0, Math.PI * 2 );
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context.fill();
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}
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return canvas;
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}
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}
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export { FlakesTexture };
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