Add a normal map or a mask map to a sprite in URP

To add surface detail such as bumps, grooves, and scratches to a 2D spriteA 2D graphic objects. If you are used to working in 3D, Sprites are essentially just standard textures but there are special techniques for combining and managing sprite textures for efficiency and convenience during development. More info
See in Glossary in the Universal Render PipelineA series of operations that take the contents of a Scene, and displays them on a screen. Unity lets you choose from pre-built render pipelines, or write your own. More info
See in Glossary (URP), add the following texture maps:

• A normal mapA type of Bump Map texture that allows you to add surface detail such as bumps, grooves, and scratches to a model which catch the light as if they are represented by real geometry.
  See in Glossary to make details catch the light from a 2D light as if they represent real geometry. For more information, refer to Introduction to normal maps.
• A mask map to control which areas of the sprite receive light, to create highlights, rim lighting, and shadowing.

In 2D projects, normal maps and mask maps are called secondary textures of the sprite. You add them using the Secondary Textures overlay of the Sprite Editor window.

Note: The mask map texture you add as a secondary texture is different to the sprite maskA texture which defines which areas of an underlying image to reveal or hide. More info
See in Glossary you use to hide or reveal parts of a sprite.

Import a texture map

To import a texture map, follow these steps:

1. Drag the texture map into the Project window to import it into your project.
2. In the InspectorA Unity window that displays information about the currently selected GameObject, asset or project settings, allowing you to inspect and edit the values. More info
   See in Glossary window, set the Texture Type to Normal Map for a normal map, or Default for a mask map.
3. Disable sRGB (Color Texture).

To make sure the lighting works correctly, make sure your texture map lines up with the sprite texture. Unity samples texture maps using the same uv coordinates it uses to sample the sprite texture.

Add the texture map to a sprite

Add the normal map or mask map as a Secondary Texture to the sprite. Follow these steps:

1. Make sure the Sprite RendererA component that lets you display images as Sprites for use in both 2D and 3D scenes. More info
   See in Glossary component of the sprite uses a material that supports texture maps, for example the default Sprite-Lit-Default material. For more information, refer to Prepare and upgrade sprites for 2D lighting in URP.

2. Select the original texture of the sprite in the Project window, then select Open Sprite Editor.

3. Select the Secondary Textures tab from the dropdown.

   Unity displays the Secondary Textures overlay in the bottom-right corner of the Sprite Editor window.

4. In the Secondary Textures overlay, select the Add (+) button to add a new secondary texture.

5. Select the Name dropdown, then select _NormalMap for a normal map, or _MaskTex for a mask map.

   Note: The dropdown might also include names used by other Unity packages you installed, even if you have since uninstalled the packages.

6. To select your normal map or mask map, drag it from the Project window to the Texture field, or select the picker (⊙).

7. Select Apply.

To display the secondary texture in the Sprite Editor window, select it in the Secondary Textures overlay. To display the sprite texture again, select anywhere outside of the overlay.

Configure a 2D light to use the texture map

To check the effect of the texture map on the sprite texture under a 2D light, follow these steps:

1. Add a 2D light to the sceneA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
   See in Glossary.
2. Select the light in the Hierarchy window to open its Inspector window.
3. To enable the normal map, in the Normal Maps section, set Use Normal Map to Fast or Accurate.
4. To enable the mask map, in the Blending section, set Blend Style to Multiply with Mask (R) or Additive with Mask (R).

Additional resources

• Secondary textures - Lit sprites and 2D VFX tutorial on the Unity YouTube channel
• 2D lighting for pixel art on the Unity Learn website