The following advice helps you understand how to use Unity’s rendering features to realistically mimic the real world, and quickly achieve your project’s believable visual goal. This covers:
For more in-depth information, see Unity’s lighting and rendering tutorial.
In simple terms, the linear rendering mode prepares Unity to do lighting and shading calculations using physically accurate mathematics before transforming the final output into the format that works best for monitors.
To specify a gamma or linear workflow:
In Unity, navigate to Edit > Project Settings from the main menu, and then select the Player category.
Go to Other Settings > Rendering and change the Color Space to Linear.
Defining your color space should be one of the earliest decisions in your project because of the drastic impact on the final shading and lighting results. For more advice on each workflow, see Linear or gamma workflow.
The Spotlight Tunnel Sample Scene uses the deferred shading rendering path. This allows you to:
Work with multiple dynamic lights efficiently
Combine multiple reflection cubemaps
Use the existing Screen Space Reflection features in Unity 2017+
To set the rendering path in the Editor, select Edit > Project Settings, and then select the Graphics category. Alternatively, you can select the Main Camera in your Scene, and then set the Rendering Path in the Inspector window.
For more information on the rendering mode, see Rendering Pipeline Details.
To display HDR lighting properly, install the Unity post-processing stack V1 in your project, and follow these steps to set it up and enable tonemapping:
Create a Post-Processing Profile Asset in your project and configure it:
Select the Main Camera in your Scene, click Add Component in the Inspector window, and choose Post-Processing Behaviour.
In the Profile field, enter the post-processing profile you created.
The Spotlight Tunnel sample scene uses the post-processing stack V1. For advice on using post-processing stack V2, refer to the package readme.
When rendering believable lighting, you’re dealing with lighting values and emissive surfaces that have a brightness higher than 1 (high dynamic range), much like real life. You then need to remap these values to the proper screen range (see tonemapping). The high dynamic range setting is crucial because it allows the Unity camera to process high values, rather than clip them. To enable HDR, select the Main Camera in your Scene and ensure that Allow HDR is checked in the Inspector window.
The Spotlight Tunnel Sample Scene doesn’t use baked lighting. However, if you’re planning to use HDR baked lighting, set the light map encoding to HDR light map for consistent results.
To set lightmap encoding in Unity, go to Edit > Project Settings, and then select the Player category, expand the Other Settings panel, and navigate to Lightmap Encoding. For more information, see Lightmaps: Technical information.
To see the tonemapper while working with the Scene, enable Image Effects in the drop-down toolbar menu at the top of the Scene view. In the following image, notice the highlight rendition and the dark tunnel value separation improvements in the tonemapped Scene. If you look at the non-tonemapped Scene, you can see how the highlights didn’t converge to a unified color (the yellowish burning sun in this case).
This setup essentially tries to replicate how a digital camera captures a Scene with a fixed exposure (without exposure adaptation/eye adaptation features enabled).
At this point, you have a proper foundational Scene rendering setup that should give believable results with a wide range of content: