Creating a High Dynamic Range Image Skybox

1. Introduction

High Dynamic Range Images use various techniques to capture a greater range of lighting information in a photograph. Unity is able to read this additional lighting information and convert it to a representation of the environment lighting represented in the image. It’s possible to light entire Scenes using only a HDRI Skybox. Setting up a HDRI Skybox in Unity just takes a few steps. In this tutorial, we’ll create a Skybox Material and setup our Scene.

2. Creating a High Dynamic Range Image Skybox

High Dynamic Range Images use various techniques to capture a greater range of lighting information in a photograph. Unity is able to read this additional lighting information and convert it to a representation of the environment lighting represented in the image. It’s possible to light entire Scenes using only a HDRI Skybox. Setting up a HDRI Skybox in Unity just takes a few steps. In this tutorial, we’ll create a Skybox Material and setup our Scene.

• Download and import the Unity HDRI Pack from the Asset Store. If you’d like to use your own image, it needs to be in the Cube format. For more information on formatting your Cubemap, see the Unity Manual. For this workflow, we’ll use the Kirby Cove HDRI from the Unity HDRI Pack.

• Right-click in the Project pane and select Create > Material. Name this material KCSky.

• In the Inspector for KCSky, click Shader and set it to Skybox > Cubemap (Figure 01).

Figure 01: The Cubemap Shader makes Skybox creation a snap.

• Click the Select button to set the Cubemap (Figure 02).

Figure 02: Click here to select the Cubemap.

• In the “Select Cubemap” pop-up, double-click on KirbyCoveWhiteBalanced (Figure 03).

Figure 03: Some Cubemaps in the Unity HDRI Pack have alternate versions with no sun, which may be preferable depending on your lighting setup.

• From the Window drop-down, select Rendering > Lighting Settings (Figure 04).

Figure 04: Accessing lighting settings

• Drag and drop KCSky into the Skybox Material slot (Figure 05).

Figure 05: Selecting the Skybox Material

• The Skybox is now in place and ready for use (Figure 06).

Figure 06: The Skybox in action

3. Conclusion

As the lighting is recalculated, notice how the Skybox affects the lighting in the scene. Each object appears to pick up lighting color and intensity from the Skybox, which makes the objects look like they belong in the environment. A Skybox is a quick way to add immersive realism to your world, whether it’s based in reality or fantasy.