import * as THREE from "three" ; /**
 * `VignetteShader`.
 */ export const VignetteShader = { uniforms : { tDiffuse : { value : null } , offset : { value : 1.0 } , darkness : { value : 1.0 } } , vertexShader : `
        varying vec2 vUv;
        void main() {
            vUv = uv;
            gl_Position = projectionMatrix * modelViewMatrix * vec4(position, 1.0);
        }` , fragmentShader : `
        uniform float offset;
        uniform float darkness;
        uniform sampler2D tDiffuse;
        varying vec2 vUv;
        void main() {
            vec4 texel = texture2D( tDiffuse, vUv );
            vec2 uv = ( vUv - vec2( 0.5 ) ) * vec2( offset );
            gl_FragColor = vec4( mix( texel.rgb, vec3( 1.0 - darkness ), dot( uv, uv ) ), texel.a );
        }` } ;