Normal Mapping

Normal mapping (or Dot3 bump mapping) is a term used in 3D computer graphics and is used to obtain greater detail in shadows without increasing the number of polygons.

When normal mapping relevant to the lighting information on the orientation of the normals are transferred from a high to a low-resolution 3D model. The detail of the surface is thus obtained optically. Visible the low detail is only on the silhouette that corresponds still that of the low-resolution model. Often this technique is used in the field of real-time 3D graphics (eg, computer games). Especially for multiple light sources, this technology was the introduction of pixel shaders easier (since DirectX 9.0 or OpenGL 1.5 or as OpenGL extensions ).

Disadvantages

Normal mapping is strongly angle- dependent. The steeper you look at a surface, the less effect the normal map. With a viewing angle of 0 degrees no more effect is visible.