https://github.com/supermedium/aframe-environment-component
Make sure you are using A-Frame 0.6.0 or later. Then just include aframe-environment-component.js in your HTML.
This can go below the a-frame script you inside <head>
<head>
<script src="<https://unpkg.com/[email protected]/dist/aframe-environment-component.min.js>"></script>
</head>
You can add the environment component to an entity <a-entity> in <a-scene> like this:
<body>
<a-scene>
<a-entity environment></a-entity>
</a-scene>
</body>
Apart from using a preset, you can tweak the environment with many parameters, like this:
<a-entity environment="lightPosition: 1 5 -2; groundColor: #445888"></a-entity>
You can also select a preset but change some of its parameters:
<a-entity environment="preset: forest"></a-entity>