The term "shading" refers to the representation of shades. The designer uses a shader to define the lighting properties through the colour, the reflectance and the transparency. These determine how the light will appear on an object and affect the surroundings. The lighting effect of the material properties always depends on the type and position of the light sources and is visible only in the combination of shading factors and lighting: hence, shiny spots on reflecting surfaces appear only when the light from the light sources shines directly onto these surfaces.