scene.environment set to anything other than PMREMGenerator output is unuseable - bug or feature?

for example,

var envMap = new THREE.Texture( whatever );
envMap.mapping = THREE.EquirectangularReflectionMapping;
envMap.needsUpdate = true;
scene.environment = envMap;

will creaate ridiculously dark scene, while running same texture through PMREMGenerator performs as expected.

[Mugen87]

It’s already noted in the docs that you can only use an env map in cube map format with MeshStandardMaterial:

Note: only cube environment maps are supported for MeshStandardMaterial. If you want to use an equirectangular map you will need to use WebGLCubeRenderTarget.fromEquirectangularTexture().

So this code should produce a response:

var cubeRenderTarget = new WebGLCubeRenderTarget( 1024 ).fromEquirectangularTexture( renderer, envMap );
scene.environment = cubeRenderTarget.texture;

Also set metalness to 1 and roughness to 0 to better see the env map.

https://jsfiddle.net/nt4pL0dg/

[makc]

So, feature then.