Example of parallax mapping. The walls are textures with parallax maps. Screenshot taken from one of the base examples of the opensource Irrlicht 3d engine. Irrlicht (ˈɪɐ̯lɪçt in German is an Open source 3D engine written in C++.

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 rendering applications such as video games. ' Bump mapping' is a Computer graphics technique where at each Pixel, a perturbation to the Surface normal of the object being rendered is In 3D computer graphics, normal mapping is an application of the technique known as Bump mapping. Rendering is the process of generating an image from a model, by means of computer programs A video game is a Game that involves interaction with a User interface to generate visual feedback on a video device. To the end user, this means that textures such as stone walls, will have more apparent depth and thus greater realism with less of an influence on the performance of the simulation. Texture mapping is a method for adding detail surface texture or colour to a computer-generated graphic or 3D model. Parallax mapping was introduced by Tomomichi Kaneko et al^[1] in 2001. Year 2001 ( MMI) was a Common year starting on Monday according to the Gregorian calendar.

Parallax mapping is implemented by displacing the texture coordinates at a point on the rendered polygon by a function of the view angle in tangent space (the angle relative to the surface normal) and the value of the height map at that point. At steeper view angles the texture coordinates are displaced more, and so give the illusion of depth due to parallax effects as the view changes. Parallax is an apparent displacement or difference of orientation of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between

Parallax mapping described by Kaneko is a single step process that does not account for occlusion. Subsequent enhancements have been made to the algorithm incorporating iterative approaches to allow for occlusion and accurate silhouette rendering^[2].

Steep parallax mapping

Steep parallax mapping is one name for the class of algorithms that trace rays against heightfields. The idea is to walk along a ray that has entered the heightfield's volume, finding the intersection point of the ray with the heightfield. This closest intersection is what part of the heightfield is truly visible. Relief mapping is another common name for these techniques.

Interval mapping improves on the usual binary search done in relief mapping by creating a line between known inside and outside points and choosing the next sample point by intersecting this line with a ray, rather than using the midpoint as in a traditional binary search.

List of video games that feature parallax mapping

Here is a list of video games that feature parallax mapping. Only seventh generation video game consoles and high-end PC's are capable of rendering parallax mapping in-game, so all of the following games are considered 'next-gen' games.

• Tom Clancy's Splinter Cell: Chaos Theory: PC version, Shader Model 3. Tom Clancy's Splinter Cell Chaos Theory is a critically acclaimed third-person Stealth-based video game developed and published by Ubisoft. 0
• Halo 3: Bungie Studios
• Perfect Dark Zero (adds depth to ground rocks/walls)
• Kameo (adds depth to walls and bricks)
• F.E.A.R (adds depth to decals and certain walls)
• The Elder Scrolls IV Oblivion (depth to stone walls)
• Grand Theft Auto IV (bullet holes and wall cracks from collisions)
• Age of Conan: Hyborian Adventures

See also

• Parallax

External links

• Comparison from the Irrlicht Engine: With Parallax mapping vs. Halo 3 is a First-person shooter Video game developed by Bungie exclusively for the Xbox 360. Bungie is an American Video game developer founded in May 1991 under the name Perfect Dark Zero is a First-person shooter Video game developed by Rare and published by Microsoft exclusively for the Kameo Elements of Power is a Video game launched for the Microsoft Xbox 360 Video game console and developed by Rare FEAR First Encounter Assault Recon is a Survival horror First-person shooter developed by Monolith Productions and published by The Elder Scrolls IV Oblivion is a Single player Fantasy -themed action-oriented Computer role-playing game developed by Bethesda Game Studios Age of Conan Hyborian Adventures is a fantasy-themed massively multiplayer online role-playing game (MMORPG developed by the Norwegian computer Parallax is an apparent displacement or difference of orientation of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between Irrlicht (ˈɪɐ̯lɪçt in German is an Open source 3D engine written in C++. Without Parallax mapping
• Parallax mapping implementation in DirectX, forum topic
• Parallax Mapped Bullet Holes - Details the algorithm used for F. E. A. R. style bullet holes.
• Interval Mapping
• Parallax Mapping with Offset Limiting
• Steep Parallax Mapping

References