There are three ways you can create skyboxes and bring them into AltSpace, and one is definitely easier than the other two, but they all come with pros and cons. Depending on how serious you are about the skybox, you may be happy with doing one over the other, and there is no right or wrong way.
[NEW September 2021]
The skybox MRE hosted by AltSpace has been released. It allows you to take a 360 image and load it into a dome for you to resize. You can change them just by entering a valid URL.
To access the feature skybox MRE by navigating to World Editor > Featured > SDK Apps > Skybox (on page 2).
Creating a skybox within AltSpaceVR website
All you need is a 360 image that you can find both free and paid assets for around the internet and I will include a few websites that you can use. Or if you have the 360 option on your phone or HD camera you can snap your own photos and control the quality from the start.
One of the noticeable drawbacks is you will often have a line visible in the sky where the image folds. Most people find clever ways to hide that line from view by putting a building or a mountain in the way.
The other limitation is that for your skybox to be used in a space for an ‘AltSpace Main Event‘ you will have to keep your skybox to a maximum size of 2MB.
You will also need to upload 360 images rather than just an image so you will need to do some careful selecting and previewing images so you aren’t disappointed when you upload it and realise you just uploaded a normal image.
If you have skills in photo editing you can try your luck in editing your photo which would allow you to compress your image size down further and maybe be able to retain the same quality.
Finding 360 images
https://unsplash.com/s/photos/360
https://www.360cities.net/
https://pixexid.com/search/360%20panoramic
https://www.dreamstime.com/photos-images/360.html
https://all-free-download.com/free-photos/panorama-360.html
https://www.flickr.com/groups/360degrees/
Uploading by Prefab Bundles Zip
I haven’t tried this myself but you can upload an asset bundle and call the prefab in the field to specifiy. The advantage is you can do more sophisticated skyboxes with lighting and shading assigned but I don’t know anything about how this is done in Unity so I will come back and update this section.
Implementing skyboxes into your Unity template
This is probably the ultimate way to implement it but requires knowledge of Unity and uploading and requires knowledge specific to Unity skyboxes and how to create them in the first place.
Unity documentation has a specific guide for building skyboxes here.
If you want more specific information about rendering there’s a skybox focused article here to.
There are FREE and paid Unity skyboxes you can import easily
If you read this guide, you will learn how to find skyboxes easily. Search for them, import them, and drag them into your scene. If you feel brave, you can try reverse-engineering the skyboxes and replacing the background image. This way also learning how they work.
