Parallax Mapping

Parallax mapping ( also called offset mapping or virtual displacement mapping) is an enhancement of the bump mapping or normal mapping techniques applied to textures in 3D image synthesis applications and computer games.

For end users ( game designers, players) which means that the representation of relief-like surfaces such as stone walls more apparent depth and thus greater realism has in the use of textures, without requiring the computational complexity of displacement mapping.

Parallax mapping in 2001 by Tomomichi Kaneko et al. introduced.

Parallax mapping is generated by the displacement of the texture coordinates at the point of the polygon represented by a function of viewing angle relative to the tangent plane (defined by the surface normal ), and the value of the field level at that point. At relatively shallow angles to the tangent plane, the texture coordinates are displaced more, thus generating by parallax at the view point change the illusion of depth.

Parallax mapping was introduced by Kaneko as a process in one step, not taken into account which concealment. Subsequent improvements to the algorithm, added that iterative methods are considered to occlusions and the accurate representation of silhouettes.

Steep parallax mapping

Steep parallax mapping summarizes a class of algorithms that follow the lines of sight and test against height fields. The underlying idea is to trace a ray intersects the volume of a height field, and to find its intersection with the height field. This nearest intersection determines which portion of the height field is really visible. Relief mapping and parallax occlusion mapping are other known names for these techniques.

Interval mapping improves usually carried out in relief mapping binary search by a line between points that are known to be generated both inside and outside and it is cut with a beam, instead of as usual to use the center of the binary search.