Relief mapping (computer graphics)

Last updated

In computer graphics, relief mapping is a texture mapping technique first introduced in 2000 [1] used to render the surface details of three-dimensional objects accurately and efficiently. [2] It can produce accurate depictions of self-occlusion, self-shadowing, and parallax. [3] It is a form of short-distance ray tracing done in a pixel shader.[ citation needed ] Relief mapping is highly comparable in both function and approach to another displacement texture mapping technique, Parallax occlusion mapping, considering that they both rely on ray tracing, though the two are not to be confused with each other, as parallax occlusion mapping uses reverse heightmap tracing.

Contents

See also

Related Research Articles

<span class="mw-page-title-main">Rendering (computer graphics)</span> Process of generating an image from a model

Rendering or image synthesis is the process of generating a photorealistic or non-photorealistic image from a 2D or 3D model by means of a computer program. The resulting image is referred to as the render. Multiple models can be defined in a scene file containing objects in a strictly defined language or data structure. The scene file contains geometry, viewpoint, textures, lighting, and shading information describing the virtual scene. The data contained in the scene file is then passed to a rendering program to be processed and output to a digital image or raster graphics image file. The term "rendering" is analogous to the concept of an artist's impression of a scene. The term "rendering" is also used to describe the process of calculating effects in a video editing program to produce the final video output.

<span class="mw-page-title-main">Global illumination</span> Group of rendering algorithms used in 3D computer graphics

Global illumination (GI), or indirect illumination, is a group of algorithms used in 3D computer graphics that are meant to add more realistic lighting to 3D scenes. Such algorithms take into account not only the light that comes directly from a light source, but also subsequent cases in which light rays from the same source are reflected by other surfaces in the scene, whether reflective or not.

<span class="mw-page-title-main">Ray tracing (graphics)</span> Rendering method

In 3-D computer graphics, ray tracing is a technique for modeling light transport for use in a wide variety of rendering algorithms for generating digital images.

<span class="mw-page-title-main">Particle system</span> Technique in game physics, motion graphics and computer graphics

A particle system is a technique in game physics, motion graphics, and computer graphics that uses many minute sprites, 3D models, or other graphic objects to simulate certain kinds of "fuzzy" phenomena, which are otherwise very hard to reproduce with conventional rendering techniques – usually highly chaotic systems, natural phenomena, or processes caused by chemical reactions.

<span class="mw-page-title-main">Volume rendering</span> Representing a 3D-modeled object or dataset as a 2D projection

In scientific visualization and computer graphics, volume rendering is a set of techniques used to display a 2D projection of a 3D discretely sampled data set, typically a 3D scalar field.

<span class="mw-page-title-main">Lightmap</span> Data structure used in lightmapping

A lightmap is a data structure used in lightmapping, a form of surface caching in which the brightness of surfaces in a virtual scene is pre-calculated and stored in texture maps for later use. Lightmaps are most commonly applied to static objects in applications that use real-time 3D computer graphics, such as video games, in order to provide lighting effects such as global illumination at a relatively low computational cost.

<span class="mw-page-title-main">Parallax mapping</span> Texture mapping technique

Parallax mapping is an enhancement of the bump mapping or normal mapping techniques applied to textures in 3D rendering applications such as video games. 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. Parallax mapping was introduced by Tomomichi Kaneko et al., in 2001.

<span class="mw-page-title-main">Non-photorealistic rendering</span> Style of rendering

Non-photorealistic rendering (NPR) is an area of computer graphics that focuses on enabling a wide variety of expressive styles for digital art, in contrast to traditional computer graphics, which focuses on photorealism. NPR is inspired by other artistic modes such as painting, drawing, technical illustration, and animated cartoons. NPR has appeared in movies and video games in the form of cel-shaded animation as well as in scientific visualization, architectural illustration and experimental animation.

<span class="mw-page-title-main">Subsurface scattering</span>

Subsurface scattering (SSS), also known as subsurface light transport (SSLT), is a mechanism of light transport in which light that penetrates the surface of a translucent object is scattered by interacting with the material and exits the surface potentially at a different point. Light generally penetrates the surface and gets scattered a number of times at irregular angles inside the material before passing back out of the material at a different angle than it would have had if it had been reflected directly off the surface.

<span class="mw-page-title-main">Reflection mapping</span>

In computer graphics, reflection mapping or environment mapping is an efficient image-based lighting technique for approximating the appearance of a reflective surface by means of a precomputed texture. The texture is used to store the image of the distant environment surrounding the rendered object.

<span class="mw-page-title-main">High-dynamic-range rendering</span> Rendering of computer graphics scenes by using lighting calculations done in high-dynamic-range

High-dynamic-range rendering, also known as high-dynamic-range lighting, is the rendering of computer graphics scenes by using lighting calculations done in high dynamic range (HDR). This allows preservation of details that may be lost due to limiting contrast ratios. Video games and computer-generated movies and special effects benefit from this as it creates more realistic scenes than with more simplistic lighting models.

In computer graphics, per-pixel lighting refers to any technique for lighting an image or scene that calculates illumination for each pixel on a rendered image. This is in contrast to other popular methods of lighting such as vertex lighting, which calculates illumination at each vertex of a 3D model and then interpolates the resulting values over the model's faces to calculate the final per-pixel color values.

<span class="mw-page-title-main">Shadow mapping</span> Method to draw shadows in computer graphic images

Shadow mapping or shadowing projection is a process by which shadows are added to 3D computer graphics. This concept was introduced by Lance Williams in 1978, in a paper entitled "Casting curved shadows on curved surfaces." Since then, it has been used both in pre-rendered and realtime scenes in many console and PC games.

<span class="mw-page-title-main">3D rendering</span> Process of converting 3D scenes into 2D images

3D rendering is the 3D computer graphics process of converting 3D models into 2D images on a computer. 3D renders may include photorealistic effects or non-photorealistic styles.

Self-Shadowing is a computer graphics lighting effect, used in 3D rendering applications such as computer animation and video games. Self-shadowing allows non-static objects in the environment, such as game characters and interactive objects, to cast shadows on themselves and each other. For example, without self-shadowing, if a character puts their right arm over the left, the right arm will not cast a shadow over the left arm. If that same character places a hand over a ball, that hand will cast a shadow over the ball.

Computer graphics lighting is the collection of techniques used to simulate light in computer graphics scenes. While lighting techniques offer flexibility in the level of detail and functionality available, they also operate at different levels of computational demand and complexity. Graphics artists can choose from a variety of light sources, models, shading techniques, and effects to suit the needs of each application.

Parallax occlusion mapping (POM) is an enhancement of the parallax mapping technique. Parallax occlusion mapping is used to procedurally create 3D definition in textured surfaces, using a displacement map instead of through the generation of new geometry. This allows developers of 3D rendering applications to add 3D complexity in textures, which correctly change relative to perspective and with self occlusion in real time, without sacrificing the processor cycles required to create the same effect with geometry calculations.

In computing, 3D interaction is a form of human-machine interaction where users are able to move and perform interaction in 3D space. Both human and machine process information where the physical position of elements in the 3D space is relevant.

<span class="mw-page-title-main">Displacement mapping</span> Computer graphics technique

Displacement mapping is an alternative computer graphics technique in contrast to bump, normal, and parallax mapping, using a texture or height map to cause an effect where the actual geometric position of points over the textured surface are displaced, often along the local surface normal, according to the value the texture function evaluates to at each point on the surface. It gives surfaces a great sense of depth and detail, permitting in particular self-occlusion, self-shadowing and silhouettes; on the other hand, it is the most costly of this class of techniques owing to the large amount of additional geometry.

This is a glossary of terms relating to computer graphics.

References

  1. Oliveira, Manuel M. and Bishop, Gary and McAllister, David (2000). "Relief texture mapping". Proceedings of the 27th annual conference on Computer graphics and interactive techniques - SIGGRAPH '00. pp. 359–368. doi:10.1145/344779.344947. ISBN   1581132085. S2CID   598957.{{cite book}}: CS1 maint: multiple names: authors list (link)
  2. Policarpo, F., Oliveira, M. M., Comba, J. L. D. (2005). "Real-time relief mapping on arbitrary polygonal surfaces" (PDF). Proceedings of the 2005 symposium on Interactive 3D graphics and games. pp. 155–162. doi:10.1145/1053427.1053453. ISBN   1595930132. S2CID   3445302.{{cite book}}: CS1 maint: multiple names: authors list (link)
  3. Policarpo, F., Oliveira, M. M. (2006). "Relief mapping of non-height-field surface details" (PDF). Proceedings of the 2006 symposium on Interactive 3D graphics and games - SI3D '06. p. 55. doi:10.1145/1111411.1111422. ISBN   159593295X. S2CID   11331719 . Retrieved 18 February 2011.{{cite book}}: CS1 maint: multiple names: authors list (link)