59 lines
903 B
JavaScript
59 lines
903 B
JavaScript
|
/**
|
||
|
|
* Afterimage shader
|
||
|
|
* I created this effect inspired by a demo on codepen:
|
||
|
|
* https://codepen.io/brunoimbrizi/pen/MoRJaN?page=1&
|
||
|
|
*/
|
||
|
|
|
||
|
|
const AfterimageShader = {
|
||
|
|
|
||
|
|
name: 'AfterimageShader',
|
||
|
|
|
||
|
|
uniforms: {
|
||
|
|
|
||
|
|
'damp': { value: 0.96 },
|
||
|
|
'tOld': { value: null },
|
||
|
|
'tNew': { value: null }
|
||
|
|
|
||
|
|
},
|
||
|
|
|
||
|
|
vertexShader: /* glsl */`
|
||
|
|
|
||
|
|
varying vec2 vUv;
|
||
|
|
|
||
|
|
void main() {
|
||
|
|
|
||
|
|
vUv = uv;
|
||
|
|
gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );
|
||
|
|
|
||
|
|
}`,
|
||
|
|
|
||
|
|
fragmentShader: /* glsl */`
|
||
|
|
|
||
|
|
uniform float damp;
|
||
|
|
|
||
|
|
uniform sampler2D tOld;
|
||
|
|
uniform sampler2D tNew;
|
||
|
|
|
||
|
|
varying vec2 vUv;
|
||
|
|
|
||
|
|
vec4 when_gt( vec4 x, float y ) {
|
||
|
|
|
||
|
|
return max( sign( x - y ), 0.0 );
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
void main() {
|
||
|
|
|
||
|
|
vec4 texelOld = texture2D( tOld, vUv );
|
||
|
|
vec4 texelNew = texture2D( tNew, vUv );
|
||
|
|
|
||
|
|
texelOld *= damp * when_gt( texelOld, 0.1 );
|
||
|
|
|
||
|
|
gl_FragColor = max(texelNew, texelOld);
|
||
|
|
|
||
|
|
}`
|
||
|
|
|
||
|
|
};
|
||
|
|
|
||
|
|
export { AfterimageShader };
|