Note. Unity 5 introduced the Standard Shader which replaces this shader.
This shader will simulate reflective surfaces such as cars, metal objects etc. It requires an environment CubemapA collection of six square textures that can represent the reflections in an environment or the skybox drawn behind your geometry. The six squares form the faces of an imaginary cube that surrounds an object; each face represents the view along the directions of the world axes (up, down, left, right, forward and back). More info
See in Glossary which will define what exactly is reflected. The main texture’s alpha channel defines the strength of reflection on the object’s surface. Any 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 lights will add illumination on top of what is reflected.
Like a Diffuse shader, this computes a simple (Lambertian) lighting model. The lighting on the surface decreases as the angle between it and the light decreases. The lighting depends only on the angle, and does not change as the cameraA component which creates an image of a particular viewpoint in your scene. The output is either drawn to the screen or captured as a texture. More info
See in Glossary moves or rotates around.
Normal mapping simulates small surface details using a texture, instead of spending more polygons to actually carve out details. It does not actually change the shape of the object, but uses a special texture called 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 achieve this effect. In the normal map, each pixelThe smallest unit in a computer image. Pixel size depends on your screen resolution. Pixel lighting is calculated at every screen pixel. More info
See in Glossary’s color value represents the angle of the surface normal. Then by using this value instead of the one from geometry, lighting is computed. The normal map effectively overrides the meshThe main graphics primitive of Unity. Meshes make up a large part of your 3D worlds. Unity supports triangulated or Quadrangulated polygon meshes. Nurbs, Nurms, Subdiv surfaces must be converted to polygons. More info
See in Glossary’s geometry when calculating lighting of the object.
You can import normal maps created outside of Unity, or you can import a regular grayscale image and convert it to a Normal Map from within Unity. (This page refers to a legacy shader which has been superseded by the Standard Shader, but you can learn more about how to use Normal Maps in the Standard Shader)
The Normal Map is a tangent space type of normal map. Tangent space is the space that “follows the surface” of the model geometry. In this space, Z always points away from the surface. Tangent space Normal Maps are a bit more expensive than the other “object space” type Normal Maps, but have some advantages:
Diffuse computes a simple (Lambertian) lighting model. The lighting on the surface decreases as the angle between it and the light decreases. The lighting depends only on this angle, and does not change as the camera moves or rotates around.
Generally, this shader is cheap to render. For more details, please view the Shader Peformance page.