64 lines
1.0 KiB
JavaScript
64 lines
1.0 KiB
JavaScript
/**
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* @module AfterimageShader
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* @three_import import { AfterimageShader } from 'three/addons/shaders/AfterimageShader.js';
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*/
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/**
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* Inspired by [Three.js FBO motion trails]{@link https://codepen.io/brunoimbrizi/pen/MoRJaN?page=1&}.
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*
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* @constant
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* @type {ShaderMaterial~Shader}
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*/
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const AfterimageShader = {
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name: 'AfterimageShader',
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uniforms: {
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'damp': { value: 0.96 },
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'tOld': { value: null },
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'tNew': { value: null }
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},
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vertexShader: /* glsl */`
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varying vec2 vUv;
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void main() {
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vUv = uv;
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gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );
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}`,
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fragmentShader: /* glsl */`
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uniform float damp;
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uniform sampler2D tOld;
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uniform sampler2D tNew;
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varying vec2 vUv;
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vec4 when_gt( vec4 x, float y ) {
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return max( sign( x - y ), 0.0 );
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}
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void main() {
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vec4 texelOld = texture2D( tOld, vUv );
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vec4 texelNew = texture2D( tNew, vUv );
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texelOld *= damp * when_gt( texelOld, 0.1 );
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gl_FragColor = max(texelNew, texelOld);
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}`
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};
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export { AfterimageShader };
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