In computer graphics
, per-pixel lighting
is commonly used to refer to a set of methods for computing illumination at each rendered pixel
of an image. These generally produce more realistic images than vertex lighting
, which only calculates illumination at each vertex of a 3D model
and then interpolates
the resulting values to calculate the per-pixel color values.
Per-pixel lighting is commonly used with other computer graphics techniques to help improve render quality, including bump mapping, specularity, phong shading and shadow volumes.
Real-time applications, such as computer games, which use modern graphics cards will normally implement per-pixel lighting algorithms using pixel shaders. Per-pixel lighting is also performed on the CPU in many high-end commercial rendering applications which typically do not render at interactive framerates.