ShaderLab: Introduction to Shaders

1. What is a Shader?

Verified with Unity 2019.4 LTS.

A Shader is a program that runs on the GPU to define how objects are rendered on screen. This program requires several inputs to process an output—sometimes via multiple passes or “steps.” These inputs vary depending on the type of shader you wish to create:

Surface Shaders: What we primarily think of when we discuss Shaders. They are responsible for defining the surface detail of objects, such as reflection, refraction, and texture blending.

Vertex Shaders: Displaces the vertices of geometry. When combined with time, these can be used to produce procedural animations.

Compute Shaders: Instance many (sometimes millions of) objects to simulate crowds, vegetation, and various other simulations.

Geometry Shaders: Tessellate existing geometry to provide higher resolution detail to models.

In this tutorial, we will be creating a Standard Surface Shader and assign it to a new Material. In Unity, Materials are what link Shaders to objects.

2. Creating a Surface Shader

1. Right-click in the Project window and navigate to Create > Shader > Standard Surface Shader (Figure 01).

Figure 01: Creating a Standard Surface Shader

Once created, you should have a new Shader in your project (Figure 02).

Figure 02: The newly created Shader Asset.

Once we have created our Shader we can assign it to a Material.

3. Creating a Material

1. Right-click in the Project window and navigate to Create > Material (Figure 03).

Alternatively, you can right click on the Shader and select Create then Material.

Figure 03: Creating a Material

Once created, you should have the following Material Asset in the project (Figure 04).

Figure 04: Material Asset

2. Select the Material and view it in the Inspector (Figure 05).

Figure 05: A look at our Material in the Inspector. Note, these are all the properties that belong to Unity’s Standard Surface Shader. They will vary depending on the kind of Shader used.

3. In the Material Inspector view, click on the drop-down next to Shaders (Figure 06).

Figure 06: The Shader selection drop-down

4. Select the Shader to use by navigating to Standard > MyShaders > MySurfaceShader (Figure 07).

Figure 07: Selecting the Shader to assign to your newly created Material

4. Conclusion

In this tutorial, you’ve learned how to create a Shader and assign it to a Material. Now, experiment with how Shaders can be used for a variety of effects by selecting different Shaders from the Shader drop-down. In order to view the results, you must assign the Material to a GameObject in the Scene. From here, you should be prepared to learn how to write different types of Shaders such as the ones outlined above.