How do I Use Normal Maps?

Normal maps are grayscale images that you use as a height map on your objects in order to give an appearance of raised or recessed surfaces. Assuming you have a model that looks like this:

We want to make the light parts of the object appear raised.

1. Draw a grayscale height map of your texture in Photoshop. White is high, black is low. Something like this:
   
2. Save the image next to your main texture.
3. In Unity, select the image and select the 24 bit RGB format and enable Generate Normal Map in the Import Settings in the Inspector:
   

1. In the Material Inspector of your model, select 'Bumped Diffuse' from the Shader drop-down:
   
2. Drag your texture from the Project window to the 'Normalmap' texture slot:
   

Your object now has a normal map applied:

Hints

• To make the bumps more noticable, either use the Bumpyness slider in the Texture Import Settings or blur the texture in Photoshop. Experiment with both approaches to get a feel for it.

Page last updated: 2010-09-10