node_modules/three/src/renderers/shaders/ShaderLib/backgroundCube.glsl.js

export const vertex = /* glsl */`
varying vec3 vWorldDirection;

#include <common>

void main() {

	vWorldDirection = transformDirection( position, modelMatrix );

	#include <begin_vertex>
	#include <project_vertex>

	gl_Position.z = gl_Position.w; // set z to camera.far

}
`;

export const fragment = /* glsl */`

#ifdef ENVMAP_TYPE_CUBE

	uniform samplerCube envMap;

#elif defined( ENVMAP_TYPE_CUBE_UV )

	uniform sampler2D envMap;

#endif

uniform float flipEnvMap;
uniform float backgroundBlurriness;
uniform float backgroundIntensity;
uniform mat3 backgroundRotation;

varying vec3 vWorldDirection;

#include <cube_uv_reflection_fragment>

void main() {

	#ifdef ENVMAP_TYPE_CUBE

		vec4 texColor = textureCube( envMap, backgroundRotation * vec3( flipEnvMap * vWorldDirection.x, vWorldDirection.yz ) );

	#elif defined( ENVMAP_TYPE_CUBE_UV )

		vec4 texColor = textureCubeUV( envMap, backgroundRotation * vWorldDirection, backgroundBlurriness );

	#else

		vec4 texColor = vec4( 0.0, 0.0, 0.0, 1.0 );

	#endif

	texColor.rgb *= backgroundIntensity;

	gl_FragColor = texColor;

	#include <tonemapping_fragment>
	#include <colorspace_fragment>

}
`;