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121-486: In computer graphics , a shader is a computer program that calculates the appropriate levels of light , darkness , and color during the rendering of a 3D scene —a process known as shading . Shaders have evolved to perform a variety of specialized functions in computer graphics special effects and video post-processing , as well as general-purpose computing on graphics processing units . Traditional shaders calculate rendering effects on graphics hardware with

242-527: A {\displaystyle C_{a}} and C b {\displaystyle C_{b}} stand for the color components of the pixels in the result of the "over", image A, and image B respectively, applied to each color channel (red/green/blue) individually, whereas α o {\displaystyle \alpha _{o}} , α a {\displaystyle \alpha _{a}} and α b {\displaystyle \alpha _{b}} are

363-436: A compositing algebra . For example, given two images A and B , the most common compositing operation is to combine the images so that A appears in the foreground and B appears in the background. This can be expressed as A over B . In addition to over , Porter and Duff defined the compositing operators in , held out by (the phrase refers to holdout matting and is usually abbreviated out ), atop , and xor (and

484-471: A "straight alpha" API surface, but converts them into premultiplied alpha for performance. One disadvantage of premultiplied alpha is that it can reduce the available relative precision in the RGB values when using integer or fixed-point representation for the color components. This may cause a noticeable loss of quality if the color information is later brightened or if the alpha channel is removed. In practice, this

605-466: A better approximation of a curve. As of OpenGL 4.0 and Direct3D 11, a new shader class called a tessellation shader has been added. It adds two new shader stages to the traditional model: tessellation control shaders (also known as hull shaders) and tessellation evaluation shaders (also known as Domain Shaders), which together allow for simpler meshes to be subdivided into finer meshes at run-time according to

726-406: A broad sense to describe "almost everything on computers that is not text or sound". Typically, the term computer graphics refers to several different things: Today, computer graphics is widespread. Such imagery is found in and on television, newspapers, weather reports, and in a variety of medical investigations and surgical procedures. A well-constructed graph can present complex statistics in

847-425: A color value; more complex shaders with multiple inputs/outputs are also possible. Pixel shaders range from simply always outputting the same color, to applying a lighting value, to doing bump mapping , shadows , specular highlights , translucency and other phenomena. They can alter the depth of the fragment (for Z-buffering ), or output more than one color if multiple render targets are active. In 3D graphics,

968-452: A combination of red, green and blue ( RGB ). When alpha compositing is in use, each pixel has an additional numeric value stored in its alpha channel , with a value ranging from 0 to 1. A value of 0 means that the pixel is fully transparent and the color in the pixel beneath will show through. A value of 1 means that the pixel is fully opaque. With the existence of an alpha channel, it is possible to express compositing image operations using

1089-513: A critical and commercial success of nine-figure magnitude. The studio to invent the programmable shader would go on to have many animated hits, and its work on prerendered video animation is still considered an industry leader and research trail breaker. In video games, in 1992, Virtua Racing , running on the Sega Model 1 arcade system board , laid the foundations for fully 3D racing games and popularized real-time 3D polygonal graphics among

1210-520: A discipline until the 1950s and the post- World War II period – during which time the discipline emerged from a combination of both pure university and laboratory academic research into more advanced computers and the United States military 's further development of technologies like radar , aviation , and rocketry developed during the war. New kinds of displays were needed to process the wealth of information resulting from such projects, leading to

1331-463: A display scope image of a Disney cartoon character. Electronics pioneer Hewlett-Packard went public in 1957 after incorporating the decade prior, and established strong ties with Stanford University through its founders, who were alumni . This began the decades-long transformation of the southern San Francisco Bay Area into the world's leading computer technology hub – now known as Silicon Valley . The field of computer graphics developed with

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1452-423: A display scope. One of the first interactive video games to feature recognizable, interactive graphics – Tennis for Two – was created for an oscilloscope by William Higinbotham to entertain visitors in 1958 at Brookhaven National Laboratory and simulated a tennis match. In 1959, Douglas T. Ross , while working at MIT on transforming mathematic statements into computer generated 3D machine tool vectors, created

1573-548: A feature-length motion picture using computer graphics – a goal he would achieve two decades later after his founding role in Pixar . In the same class, Fred Parke created an animation of his wife's face. The two animations were included in the 1976 feature film Futureworld . As the UU computer graphics laboratory was attracting people from all over, John Warnock was another of those early pioneers; he later founded Adobe Systems and created

1694-402: A final rendered image can be altered using algorithms defined in a shader, and can be modified by external variables or textures introduced by the computer program calling the shader. Shaders are used widely in cinema post-processing , computer-generated imagery , and video games to produce a range of effects. Beyond simple lighting models, more complex uses of shaders include: altering

1815-515: A form that is easier to understand and interpret. In the media "such graphs are used to illustrate papers, reports, theses", and other presentation material. Many tools have been developed to visualize data. Computer-generated imagery can be categorized into several different types: two dimensional (2D), three dimensional (3D), and animated graphics. As technology has improved, 3D computer graphics have become more common, but 2D computer graphics are still widely used. Computer graphics has emerged as

1936-555: A geometry shader if present, or the rasterizer . Vertex shaders can enable powerful control over the details of position, movement, lighting, and color in any scene involving 3D models . Geometry shaders were introduced in Direct3D 10 and OpenGL 3.2; formerly available in OpenGL 2.0+ with the use of extensions. This type of shader can generate new graphics primitives , such as points, lines, and triangles, from those primitives that were sent to

2057-471: A geometry shader include point sprite generation, geometry tessellation , shadow volume extrusion, and single pass rendering to a cube map . A typical real-world example of the benefits of geometry shaders would be automatic mesh complexity modification. A series of line strips representing control points for a curve are passed to the geometry shader and depending on the complexity required the shader can automatically generate extra lines each of which provides

2178-593: A great deal of founding research to the field and taught several students who would grow to found several of the industry's most important companies – namely Pixar , Silicon Graphics , and Adobe Systems . Tom Stockham led the image processing group at UU which worked closely with the computer graphics lab. One of these students was Edwin Catmull . Catmull had just come from The Boeing Company and had been working on his degree in physics. Growing up on Disney , Catmull loved animation yet quickly discovered that he did not have

2299-608: A high degree of flexibility. Most shaders are coded for (and run on) a graphics processing unit (GPU), though this is not a strict requirement. Shading languages are used to program the GPU's rendering pipeline , which has mostly superseded the fixed-function pipeline of the past that only allowed for common geometry transforming and pixel-shading functions; with shaders, customized effects can be used. The position and color ( hue , saturation , brightness , and contrast ) of all pixels , vertices , and/or textures used to construct

2420-447: A high-water mark for the field during the decade. The 1980s is also called the golden era of videogames ; millions-selling systems from Atari , Nintendo and Sega , among other companies, exposed computer graphics for the first time to a new, young, and impressionable audience – as did MS-DOS -based personal computers, Apple IIs , Macs , and Amigas , all of which also allowed users to program their own games if skilled enough. For

2541-405: A highly popular tool for computer graphics among graphic design studios and businesses. Modern computers, dating from the 1980s, often use graphical user interfaces (GUI) to present data and information with symbols, icons and pictures, rather than text. Graphics are one of the five key elements of multimedia technology. In the field of realistic rendering, Japan 's Osaka University developed

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2662-406: A leading developer of graphics boards in this decade, creating a "duopoly" in the field which exists this day. CGI became ubiquitous in earnest during this era. Video games and CGI cinema had spread the reach of computer graphics to the mainstream by the late 1990s and continued to do so at an accelerated pace in the 2000s. CGI was also adopted en masse for television advertisements widely in

2783-417: A light pen, Sketchpad allowed one to draw simple shapes on the computer screen, save them and even recall them later. The light pen itself had a small photoelectric cell in its tip. This cell emitted an electronic pulse whenever it was placed in front of a computer screen and the screen's electron gun fired directly at it. By simply timing the electronic pulse with the current location of the electron gun, it

2904-418: A mathematical function. The function can be related to a variety of variables, most notably the distance from the viewing camera to allow active level-of-detail scaling. This allows objects close to the camera to have fine detail, while further away ones can have more coarse meshes, yet seem comparable in quality. It also can drastically reduce required mesh bandwidth by allowing meshes to be refined once inside

3025-420: A model of a car, one could change the size of the tires without affecting the rest of the car. It could stretch the body of car without deforming the tires. The phrase "computer graphics" has been credited to William Fetter , a graphic designer for Boeing in 1960. Fetter in turn attributed it to Verne Hudson, also at Boeing. In 1961 another student at MIT, Steve Russell , created another important title in

3146-407: A necessity for advanced work in the field, providing considerable complexity in manipulating pixels , vertices , and textures on a per-element basis, and countless possible effects. Their shader languages HLSL and GLSL are active fields of research and development. Physically based rendering or PBR, which implements many maps and performs advanced calculation to simulate real optic light flow,

3267-479: A per-vertex basis. Newer geometry shaders can generate new vertices from within the shader. Tessellation shaders are the newest 3D shaders; they act on batches of vertices all at once to add detail—such as subdividing a model into smaller groups of triangles or other primitives at runtime, to improve things like curves and bumps , or change other attributes. Vertex shaders are the most established and common kind of 3D shader and are run once for each vertex given to

3388-442: A physical reflectance / transmittance model in 1981. A 1984 paper by Thomas Porter and Tom Duff introduced premultiplied alpha using a geometrical approach. The use of the term alpha is explained by Smith as follows: "We called it that because of the classic linear interpolation formula α A + ( 1 − α ) B {\displaystyle \alpha A+(1-\alpha )B} that uses

3509-647: A pixel shader alone cannot produce some kinds of complex effects because it operates only on a single fragment, without knowledge of a scene's geometry (i.e. vertex data). However, pixel shaders do have knowledge of the screen coordinate being drawn, and can sample the screen and nearby pixels if the contents of the entire screen are passed as a texture to the shader. This technique can enable a wide variety of two-dimensional postprocessing effects such as blur , or edge detection /enhancement for cartoon/cel shaders . Pixel shaders may also be applied in intermediate stages to any two-dimensional images— sprites or textures —in

3630-552: A revolution in the publishing world with his PostScript page description language. Adobe would go on later to create the industry standard photo editing software in Adobe Photoshop and a prominent movie industry special effects program in Adobe After Effects . James Clark was also there; he later founded Silicon Graphics , a maker of advanced rendering systems that would dominate the field of high-end graphics until

3751-565: A screen. It was the first consumer computer graphics product. David C. Evans was director of engineering at Bendix Corporation 's computer division from 1953 to 1962, after which he worked for the next five years as a visiting professor at Berkeley. There he continued his interest in computers and how they interfaced with people. In 1966, the University of Utah recruited Evans to form a computer science program, and computer graphics quickly became his primary interest. This new department would become

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3872-458: A separate and very powerful chip is used in parallel processing with a CPU to optimize graphics. The decade also saw computer graphics applied to many additional professional markets, including location-based entertainment and education with the E&;S Digistar, vehicle design, vehicle simulation, and chemistry. The 1990s' highlight was the emergence of 3D modeling on a mass scale and an rise in

3993-432: A specialized barrel shifter circuit made from discrete chips to help their Intel 8080 microprocessor animate their framebuffer graphics. The 1980s began to see the commercialization of computer graphics. As the home computer proliferated, a subject which had previously been an academics-only discipline was adopted by a much larger audience, and the number of computer graphics developers increased significantly. In

4114-433: A square for example, they do not have to worry about drawing four lines perfectly to form the edges of the box. One can simply specify that they want to draw a box, and then specify the location and size of the box. The software will then construct a perfect box, with the right dimensions and at the right location. Another example is that Sutherland's software modeled objects – not just a picture of objects. In other words, with

4235-400: A sub-field of computer science which studies methods for digitally synthesizing and manipulating visual content. Over the past decade, other specialized fields have been developed like information visualization , and scientific visualization more concerned with "the visualization of three dimensional phenomena (architectural, meteorological, medical, biological , etc.), where the emphasis

4356-463: A suitably high-end system may simulate photorealism to the untrained eye. Texture mapping has matured into a multistage process with many layers; generally, it is not uncommon to implement texture mapping, bump mapping or isosurfaces or normal mapping , lighting maps including specular highlights and reflection techniques, and shadow volumes into one rendering engine using shaders , which are maturing considerably. Shaders are now very nearly

4477-434: A vertex, while pixel shaders describe the traits (color, z-depth and alpha value) of a pixel. A vertex shader is called for each vertex in a primitive (possibly after tessellation ); thus one vertex in, one (updated) vertex out. Each vertex is then rendered as a series of pixels onto a surface (block of memory) that will eventually be sent to the screen. Shaders replace a section of the graphics hardware typically called

4598-584: A wider audience in the video game industry . The Sega Model 2 in 1993 and Sega Model 3 in 1996 subsequently pushed the boundaries of commercial, real-time 3D graphics. Back on the PC, Wolfenstein 3D , Doom and Quake , three of the first massively popular 3D first-person shooter games, were released by id Software to critical and popular acclaim during this decade using a rendering engine innovated primarily by John Carmack . The Sony PlayStation , Sega Saturn , and Nintendo 64 , among other consoles, sold in

4719-479: Is a large pixel matrix or " frame buffer ". There are three types of shaders in common use (pixel, vertex, and geometry shaders), with several more recently added. While older graphics cards utilize separate processing units for each shader type, newer cards feature unified shaders which are capable of executing any type of shader. This allows graphics cards to make more efficient use of processing power. 2D shaders act on digital images , also called textures in

4840-420: Is also used in 2D computer graphics to put rasterized foreground elements over a background. In order to combine the picture elements of the images correctly, it is necessary to keep an associated matte for each element in addition to its color. This matte layer contains the coverage information—the shape of the geometry being drawn—making it possible to distinguish between parts of the image where something

4961-539: Is an active research area as well, along with advanced areas like ambient occlusion , subsurface scattering , Rayleigh scattering , photon mapping , ray-tracing and many others. Experiments into the processing power required to provide graphics in real time at ultra-high-resolution modes like 4K Ultra HD begun, though beyond reach of all but the highest-end hardware. In cinema, most animated movies are CGI now; many animated CGI films are made per year , but few, if any, attempt photorealism due to continuing fears of

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5082-617: Is available in this case. The most popular image formats that support the alpha channel are PNG and TIFF . GIF supports alpha channels, but is considered to be inefficient when it comes to file size. Support for alpha channels is present in some video codecs, such as Animation and Apple ProRes 4444 of the QuickTime format, or in the Techsmith multi-format codec. The file format BMP generally does not support this channel; however, in different formats such as 32-bit (888–8) or 16-bit (444–4) it

5203-619: Is not usually noticeable because during typical composition operations, such as OVER, the influence of the low-precision color information in low-alpha areas on the final output image (after composition) is correspondingly reduced. This loss of precision also makes premultiplied images easier to compress using certain compression schemes, as they do not record the color variations hidden inside transparent regions, and can allocate fewer bits to encode low-alpha areas. The same “limitations” of lower quantisation bit depths such as 8 bit per channel are also present in imagery without alpha, and this argument

5324-493: Is on realistic renderings of volumes, surfaces, illumination sources, and so forth, perhaps with a dynamic (time) component". The precursor sciences to the development of modern computer graphics were the advances in electrical engineering , electronics , and television that took place during the first half of the twentieth century. Screens could display art since the Lumiere brothers ' use of mattes to create special effects for

5445-445: Is possible to save the alpha channel, although not all systems or programs are able to read it: it is exploited mainly in some video games or particular applications; specific programs have also been created for the creation of these BMPs. The RGB values of typical digital images do not directly correspond to the physical light intensities, but are rather compressed by a gamma correction function: This transformation better utilizes

5566-427: Is problematic as a result. Assuming that the pixel color is expressed using straight (non-premultiplied) RGBA tuples , a pixel value of (0, 0.7, 0, 0.5) implies a pixel that has 70% of the maximum green intensity and 50% opacity. If the color were fully green, its RGBA would be (0, 1, 0, 0.5). However, if this pixel uses premultiplied alpha, all of the RGB values (0, 0.7, 0) are multiplied, or scaled for occlusion, by

5687-413: Is that it allows for correct blending, interpolation , and filtering . Ordinary interpolation without premultiplied alpha leads to RGB information leaking out of fully transparent (A=0) regions, even though this RGB information is ideally invisible. When interpolating or filtering images with abrupt borders between transparent and opaque regions, this can result in borders of colors that were not visible in

5808-424: Is the process of combining one image with a background to create the appearance of partial or full transparency . It is often useful to render picture elements (pixels) in separate passes or layers and then combine the resulting 2D images into a single, final image called the composite . Compositing is used extensively in film when combining computer-rendered image elements with live footage . Alpha blending

5929-449: Is the world's first GPU microarchitecture that supports mesh shading through DirectX 12 Ultimate API, several months before Ampere RTX 30 series was released. In 2020, AMD and Nvidia released RDNA 2 and Ampere microarchitectures which both support mesh shading through DirectX 12 Ultimate . These mesh shaders allow the GPU to handle more complex algorithms, offloading more work from the CPU to

6050-488: The GPGPU technique to pass large amounts of data bidirectionally between a GPU and CPU was invented; speeding up analysis on many kinds of bioinformatics and molecular biology experiments. The technique has also been used for Bitcoin mining and has applications in computer vision . In the 2010s, CGI has been nearly ubiquitous in video, pre-rendered graphics are nearly scientifically photorealistic , and real-time graphics on

6171-573: The LINKS-1 Computer Graphics System , a supercomputer that used up to 257 Zilog Z8001 microprocessors , in 1982, for the purpose of rendering realistic 3D computer graphics . According to the Information Processing Society of Japan: "The core of 3D image rendering is calculating the luminance of each pixel making up a rendered surface from the given viewpoint, light source , and object position. The LINKS-1 system

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6292-452: The Metal framework . Modern video game development platforms such as Unity , Unreal Engine and Godot increasingly include node-based editors that can create shaders without the need for actual code; the user is instead presented with a directed graph of connected nodes that allow users to direct various textures, maps, and mathematical functions into output values like the diffuse color,

6413-466: The arcades , advances were made in commercial, real-time 3D graphics. In 1988, the first dedicated real-time 3D graphics boards were introduced for arcades, with the Namco System 21 and Taito Air System. On the professional side, Evans & Sutherland and SGI developed 3D raster graphics hardware that directly influenced the later single-chip graphics processing unit (GPU), a technology where

6534-426: The hue , saturation , brightness ( HSL/HSV ) or contrast of an image; producing blur , light bloom , volumetric lighting , normal mapping (for depth effects), bokeh , cel shading , posterization , bump mapping , distortion , chroma keying (for so-called "bluescreen/ greenscreen " effects), edge and motion detection , as well as psychedelic effects such as those seen in the demoscene . This use of

6655-433: The pipeline , whereas vertex shaders always require a 3D scene. For instance, a pixel shader is the only kind of shader that can act as a postprocessor or filter for a video stream after it has been rasterized . 3D shaders act on 3D models or other geometry but may also access the colors and textures used to draw the model or mesh . Vertex shaders are the oldest type of 3D shader, generally making modifications on

6776-583: The uncanny valley . Most are 3D cartoons . In videogames, the Microsoft Xbox One , Sony PlayStation 4 , and Nintendo Switch dominated the home space and were all capable of advanced 3D graphics; Windows was still one of the most active gaming platforms as well. In the 2020s', advances in ray-tracing technology allowed it to be used for real-time rendering, as well as AI-powered graphics for generating or upscaling Alpha compositing In computer graphics , alpha compositing or alpha blending

6897-482: The "alpha channel". Dithering can be used to simulate partial occlusion where only 1-bit alpha is available. For some applications, a single alpha channel is not sufficient: a stained-glass window , for instance, requires a separate transparency channel for each RGB channel to model the red, green and blue transparency separately. More alpha channels can be added for accurate spectral color filtration applications. Some order-independent transparency methods replace

7018-476: The Fixed Function Pipeline (FFP), so-called because it performs lighting and texture mapping in a hard-coded manner. Shaders provide a programmable alternative to this hard-coded approach. The basic graphics pipeline is as follows: The graphic pipeline uses these steps in order to transform three-dimensional (or two-dimensional) data into useful two-dimensional data for displaying. In general, this

7139-784: The GPU, and in algorithm intense rendering, increasing the frame rate of or number of triangles in a scene by an order of magnitude. Intel announced that Intel Arc Alchemist GPUs shipping in Q1 2022 will support mesh shaders. Ray tracing shaders are supported by Microsoft via DirectX Raytracing , by Khronos Group via Vulkan , GLSL , and SPIR-V , by Apple via Metal . Tensor shaders may be integrated in NPUs or GPUs . Tensor shaders are supported by Microsoft via DirectML , by Khronos Group via OpenVX , by Apple via Core ML , by Google via TensorFlow , by Linux Foundation via ONNX . Compute shaders are not limited to graphics applications, but use

7260-480: The Greek letter α {\displaystyle \alpha } (alpha) to control the amount of interpolation between, in this case, two images A and B". That is, when compositing image A atop image B, the value of α {\displaystyle \alpha } in the formula is taken directly from A's alpha channel. In a 2D image a color combination is stored for each picture element (pixel), often

7381-478: The alpha value 0.5, which is appended to yield (0, 0.35, 0, 0.5). In this case, the 0.35 value for the G channel actually indicates 70% green emission intensity (with 50% occlusion). A pure green emission would be encoded as (0, 0.5, 0, 0.5). Knowing whether a file uses straight or premultiplied alpha is essential to correctly process or composite it, as a different calculation is required. Emission with no occlusion cannot be represented in straight alpha. No conversion

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7502-579: The alpha values of the respective pixels. The over operator is, in effect, the normal painting operation (see Painter's algorithm ). The in and out operators are the alpha compositing equivalent of clipping . The two use only the alpha channel of the second image and ignore the color components. In addition, plus defines additive blending. If an alpha channel is used in an image, there are two common representations that are available: straight (unassociated) alpha and premultiplied (associated) alpha. The most significant advantage of premultiplied alpha

7623-569: The attitude of a satellite could be altered as it orbits the Earth. He created the animation on an IBM 7090 mainframe computer. Also at BTL, Ken Knowlton , Frank Sinden, Ruth A. Weiss and Michael Noll started working in the computer graphics field. Sinden created a film called Force, Mass and Motion illustrating Newton's laws of motion in operation. Around the same time, other scientists were creating computer graphics to illustrate their research. At Lawrence Radiation Laboratory , Nelson Max created

7744-462: The background (only whole image pixels or whole background pixels allowed). A similar effect can be achieved with a 1-bit alpha channel, as found in the 16-bit RGBA high color mode of the Truevision TGA image file format and related TARGA and AT-Vista/NU-Vista display adapters' high color graphic mode. This mode devotes 5 bits for every primary RGB color ( 15-bit RGB ) plus a remaining bit as

7865-420: The beginning of the graphics pipeline . Geometry shader programs are executed after vertex shaders. They take as input a whole primitive, possibly with adjacency information. For example, when operating on triangles, the three vertices are the geometry shader's input. The shader can then emit zero or more primitives, which are rasterized and their fragments ultimately passed to a pixel shader . Typical uses of

7986-557: The box office in this field. The Final Fantasy: The Spirits Within , released in 2001, was the first fully computer-generated feature film to use photorealistic CGI characters and be fully made with motion capture. The film was not a box-office success, however. Some commentators have suggested this may be partly because the lead CGI characters had facial features which fell into the " uncanny valley ". Other animated films like The Polar Express drew attention at this time as well. Star Wars also resurfaced with its prequel trilogy and

8107-587: The development of computer graphics as a discipline. Early projects like the Whirlwind and SAGE Projects introduced the CRT as a viable display and interaction interface and introduced the light pen as an input device . Douglas T. Ross of the Whirlwind SAGE system performed a personal experiment in which he wrote a small program that captured the movement of his finger and displayed its vector (his traced name) on

8228-453: The development of the Gouraud shading and Blinn–Phong shading models, allowing graphics to move beyond a "flat" look to a look more accurately portraying depth. Jim Blinn also innovated further in 1978 by introducing bump mapping , a technique for simulating uneven surfaces, and the predecessor to many more advanced kinds of mapping used today. The modern videogame arcade as is known today

8349-497: The earliest films dating from 1895, but such displays were limited and not interactive. The first cathode ray tube , the Braun tube , was invented in 1897 – it in turn would permit the oscilloscope and the military control panel – the more direct precursors of the field, as they provided the first two-dimensional electronic displays that responded to programmatic or user input. Nevertheless, computer graphics remained relatively unknown as

8470-417: The early 1980s, metal–oxide–semiconductor (MOS) very-large-scale integration (VLSI) technology led to the availability of 16-bit central processing unit (CPU) microprocessors and the first graphics processing unit (GPU) chips, which began to revolutionize computer graphics, enabling high-resolution graphics for computer graphics terminals as well as personal computer (PC) systems. NEC 's μPD7220

8591-416: The early 1990s. A major advance in 3D computer graphics was created at UU by these early pioneers – hidden surface determination . In order to draw a representation of a 3D object on the screen, the computer must determine which surfaces are "behind" the object from the viewer's perspective, and thus should be "hidden" when the computer creates (or renders) the image. The 3D Core Graphics System (or Core )

8712-554: The early decade with occasional significant competing presence from ATI . As the decade progressed, even low-end machines usually contained a 3D-capable GPU of some kind as Nvidia and AMD both introduced low-priced chipsets and continued to dominate the market. Shaders which had been introduced in the 1980s to perform specialized processing on the GPU would by the end of the decade become supported on most consumer hardware, speeding up graphics considerably and allowing for greatly improved texture and shading in computer graphics via

8833-680: The effects continued to set a bar for CGI in film. In videogames , the Sony PlayStation 2 and 3 , the Microsoft Xbox line of consoles, and offerings from Nintendo such as the GameCube maintained a large following, as did the Windows PC . Marquee CGI-heavy titles like the series of Grand Theft Auto , Assassin's Creed , Final Fantasy , BioShock , Kingdom Hearts , Mirror's Edge and dozens of others continued to approach photorealism , grow

8954-450: The emergence of computer graphics hardware. Further advances in computing led to greater advancements in interactive computer graphics . In 1959, the TX-2 computer was developed at MIT's Lincoln Laboratory . The TX-2 integrated a number of new man-machine interfaces. A light pen could be used to draw sketches on the computer using Ivan Sutherland 's revolutionary Sketchpad software . Using

9075-446: The end of the decade, the GPU would begin its rise to the prominence it still enjoys today. The field began to see the first rendered graphics that could truly pass as photorealistic to the untrained eye (though they could not yet do so with a trained CGI artist) and 3D graphics became far more popular in gaming , multimedia , and animation . At the end of the 1980s and the beginning of

9196-485: The field of computer graphics. By 1973, the first annual SIGGRAPH conference was held, which has become one of the focuses of the organization. SIGGRAPH has grown in size and importance as the field of computer graphics has expanded over time. Subsequently, a number of breakthroughs in the field occurred at the University of Utah in the 1970s, which had hired Ivan Sutherland . He was paired with David C. Evans to teach an advanced computer graphics class, which contributed

9317-417: The field of computer graphics. They modify attributes of pixels . 2D shaders may take part in rendering 3D geometry . Currently the only type of 2D shader is a pixel shader. Pixel shaders, also known as fragment shaders, compute color and other attributes of each "fragment": a unit of rendering work affecting at most a single output pixel . The simplest kinds of pixel shaders output one screen pixel as

9438-472: The films Flow of a Viscous Fluid and Propagation of Shock Waves in a Solid Form . Boeing Aircraft created a film called Vibration of an Aircraft . Also sometime in the early 1960s, automobiles would also provide a boost through the early work of Pierre Bézier at Renault , who used Paul de Casteljau 's curves – now called Bézier curves after Bézier's work in the field – to develop 3d modeling techniques for Renault car bodies. These curves would form

9559-489: The first ray casting algorithm, the first of a class of ray tracing -based rendering algorithms that have since become fundamental in achieving photorealism in graphics by modeling the paths that rays of light take from a light source, to surfaces in a scene, and into the camera. In 1969, the ACM initiated A Special Interest Group on Graphics ( SIGGRAPH ) which organizes conferences , graphics standards , and publications within

9680-498: The first shaders – small programs designed specifically to do shading as a separate algorithm – were developed by Pixar , which had already spun off from Industrial Light & Magic as a separate entity – though the public would not see the results of such technological progress until the next decade. In the late 1980s, Silicon Graphics (SGI) computers were used to create some of the first fully computer-generated short films at Pixar , and Silicon Graphics machines were considered

9801-402: The foundation for much curve-modeling work in the field, as curves – unlike polygons – are mathematically complex entities to draw and model well. It was not long before major corporations started taking an interest in computer graphics. TRW , Lockheed-Georgia , General Electric and Sperry Rand are among the many companies that were getting started in computer graphics by the mid-1960s. IBM

9922-455: The graphics processor. The purpose is to transform each vertex's 3D position in virtual space to the 2D coordinate at which it appears on the screen (as well as a depth value for the Z-buffer). Vertex shaders can manipulate properties such as position, color and texture coordinates, but cannot create new vertices. The output of the vertex shader goes to the next stage in the pipeline, which is either

10043-565: The history of video games , Spacewar! Written for the DEC PDP-1, Spacewar was an instant success and copies started flowing to other PDP-1 owners and eventually DEC got a copy. The engineers at DEC used it as a diagnostic program on every new PDP-1 before shipping it. The sales force picked up on this quickly enough and when installing new units, would run the "world's first video game" for their new customers. (Higginbotham's Tennis For Two had beaten Spacewar by almost three years, but it

10164-480: The intelligence in the workstation, rather than continuing to rely on central mainframe and minicomputers . Typical of the early move to high-resolution computer graphics, intelligent workstations for the computer-aided engineering market were the Orca 1000, 2000 and 3000 workstations, developed by Orcatech of Ottawa, a spin-off from Bell-Northern Research , and led by David Pearson, an early workstation pioneer. The Orca 3000

10285-399: The late 1990s and 2000s, and so became familiar to a massive audience. The continued rise and increasing sophistication of the graphics processing unit were crucial to this decade, and 3D rendering capabilities became a standard feature as 3D-graphics GPUs became considered a necessity for desktop computer makers to offer. The Nvidia GeForce line of graphics cards dominated the market in

10406-423: The later films of the original trilogy. Two other pieces of video would also outlast the era as historically relevant: Dire Straits ' iconic, near-fully-CGI video for their song " Money for Nothing " in 1985, which popularized CGI among music fans of that era, and a scene from Young Sherlock Holmes the same year featuring the first fully CGI character in a feature movie (an animated stained-glass knight ). In 1988,

10527-402: The limited number of bits in the encoded image by choosing γ {\displaystyle \gamma } that better matches the non-linear human perception of luminance. Accordingly, computer programs that deal with such images must decode the RGB values into a linear space (by undoing the gamma-compression), blend the linear light intensities, and re-apply the gamma compression to

10648-685: The mid-1980s. In 1984, Hitachi released the ARTC HD63484, the first complementary MOS (CMOS) GPU. It was capable of displaying high-resolution in color mode and up to 4K resolution in monochrome mode, and it was used in a number of graphics cards and terminals during the late 1980s. In 1986, TI introduced the TMS34010 , the first fully programmable MOS graphics processor. Computer graphics terminals during this decade became increasingly intelligent, semi-standalone and standalone workstations. Graphics and application processing were increasingly migrated to

10769-572: The millions and popularized 3D graphics for home gamers. Certain late-1990s first-generation 3D titles became seen as influential in popularizing 3D graphics among console users, such as platform games Super Mario 64 and The Legend of Zelda: Ocarina of Time , and early 3D fighting games like Virtua Fighter , Battle Arena Toshinden , and Tekken . Technology and algorithms for rendering continued to improve greatly. In 1996, Krishnamurty and Levoy invented normal mapping – an improvement on Jim Blinn's bump mapping . 1999 saw Nvidia release

10890-439: The most important research centers in graphics for nearly a decade thereafter, eventually producing some of the most important pioneers in the field. There Sutherland perfected his HMD; twenty years later, NASA would re-discover his techniques in their virtual reality research. At Utah, Sutherland and Evans were highly sought after consultants by large companies, but they were frustrated at the lack of graphics hardware available at

11011-524: The nineties were created, in France, the very first computer graphics TV series: La Vie des bêtes by studio Mac Guff Ligne (1988), Les Fables Géométriques (1989–1991) by studio Fantôme, and Quarxs , the first HDTV computer graphics series by Maurice Benayoun and François Schuiten (studio Z-A production, 1990–1993). In film, Pixar began its serious commercial rise in this era under Edwin Catmull , with its first major film release, in 1995 – Toy Story –

11132-406: The original image. Errors also occur in areas of semitransparency because the RGB components are not correctly weighted, giving incorrectly high weighting to the color of the more transparent (lower alpha) pixels. Premultiplied alpha may also be used to allow regions of regular alpha blending (e.g. smoke) and regions with additive blending mode (e.g. flame and glitter effects) to be encoded within

11253-504: The power of shaders. The first video card with a programmable pixel shader was the Nvidia GeForce 3 (NV20), released in 2001. Geometry shaders were introduced with Direct3D 10 and OpenGL 3.2. Eventually, graphics hardware evolved toward a unified shader model . Shaders are simple programs that describe the traits of either a vertex or a pixel . Vertex shaders describe the attributes (position, texture coordinates , colors, etc.) of

11374-442: The quality of CGI generally. Home computers became able to take on rendering tasks that previously had been limited to workstations costing thousands of dollars; as 3D modelers became available for home systems, the popularity of Silicon Graphics workstations declined and powerful Microsoft Windows and Apple Macintosh machines running Autodesk products like 3D Studio or other home rendering software ascended in importance. By

11495-430: The result: When combined with premultiplied alpha, pre-multiplication is done in linear space, prior to gamma compression. This results in the following formula: Note that the alpha channel may or may not undergo gamma-correction, even when the color channels do. Although used for similar purposes, transparent colors and image masks do not permit the smooth blending of the superimposed image pixels with those of

11616-400: The reverse operators rover , rin , rout , and ratop ) from a consideration of choices in blending the colors of two pixels when their coverage is, conceptually, overlaid orthogonally: [REDACTED] As an example, the over operator can be accomplished by applying the following formula to each pixel: Here C o {\displaystyle C_{o}} , C

11737-404: The same execution resources for GPGPU . They may be used in graphics pipelines e.g. for additional stages in animation or lighting algorithms (e.g. tiled forward rendering ). Some rendering APIs allow compute shaders to easily share data resources with the graphics pipeline. Shaders are written to apply transformations to a large set of elements at a time, for example, to each pixel in an area of

11858-442: The same image. This is represented by an RGBA triplet that express emission with no occlusion, such as (0.4, 0.3, 0.2, 0.0). Another advantage of premultiplied alpha is performance; in certain situations, it can reduce the number of multiplication operations (e.g. if the image is used many times during later compositing). The Porter–Duff operations have a simple form only in premultiplied alpha. Some rendering pipelines expose

11979-585: The screen, or for every vertex of a model. This is well suited to parallel processing , and most modern GPUs have multiple shader pipelines to facilitate this, vastly improving computation throughput. A programming model with shaders is similar to a higher order function for rendering, taking the shaders as arguments, and providing a specific dataflow between intermediate results, enabling both data parallelism (across pixels, vertices etc.) and pipeline parallelism (between stages). (see also map reduce ). The language in which shaders are programmed depends on

12100-507: The seminal GeForce 256 , the first home video card billed as a graphics processing unit or GPU, which in its own words contained "integrated transform , lighting , triangle setup / clipping , and rendering engines". By the end of the decade, computers adopted common frameworks for graphics processing such as DirectX and OpenGL . Since then, computer graphics have only become more detailed and realistic, due to more powerful graphics hardware and 3D modeling software . AMD also became

12221-609: The shader units instead of downsampling very complex ones from memory. Some algorithms can upsample any arbitrary mesh, while others allow for "hinting" in meshes to dictate the most characteristic vertices and edges. Circa 2017, the AMD Vega microarchitecture added support for a new shader stage—primitive shaders—somewhat akin to compute shaders with access to the data necessary to process geometry. Nvidia introduced mesh and task shaders with its Turing microarchitecture in 2018 which are also modelled after compute shaders. Nvidia Turing

12342-648: The specular color and intensity, roughness/metalness, height, normal, and so on. Automatic compilation then turns the graph into an actual, compiled shader. Computer graphics Some topics in computer graphics include user interface design , sprite graphics , rendering , ray tracing , geometry processing , computer animation , vector graphics , 3D modeling , shaders , GPU design, implicit surfaces , visualization , scientific computing , image processing , computational photography , scientific visualization , computational geometry and computer vision , among others. The overall methodology depends heavily on

12463-474: The talent for drawing. Now Catmull (along with many others) saw computers as the natural progression of animation and they wanted to be part of the revolution. The first computer animation that Catmull saw was his own. He created an animation of his hand opening and closing. He also pioneered texture mapping to paint textures on three-dimensional models in 1974, now considered one of the fundamental techniques in 3D modeling . It became one of his goals to produce

12584-460: The target environment. The official OpenGL and OpenGL ES shading language is OpenGL Shading Language , also known as GLSL, and the official Direct3D shading language is High Level Shader Language , also known as HLSL. Cg , a third-party shading language which outputs both OpenGL and Direct3D shaders, was developed by Nvidia ; however since 2012 it has been deprecated. Apple released its own shading language called Metal Shading Language as part of

12705-468: The term "shader" was introduced to the public by Pixar with version 3.0 of their RenderMan Interface Specification, originally published in May 1988. As graphics processing units evolved, major graphics software libraries such as OpenGL and Direct3D began to support shaders. The first shader-capable GPUs only supported pixel shading , but vertex shaders were quickly introduced once developers realized

12826-543: The time, so they started formulating a plan to start their own company. In 1968, Dave Evans and Ivan Sutherland founded the first computer graphics hardware company, Evans & Sutherland . While Sutherland originally wanted the company to be located in Cambridge, Massachusetts, Salt Lake City was instead chosen due to its proximity to the professors' research group at the University of Utah. Also in 1968 Arthur Appel described

12947-521: The underlying sciences of geometry , optics , physics , and perception . Computer graphics is responsible for displaying art and image data effectively and meaningfully to the consumer. It is also used for processing image data received from the physical world, such as photo and video content. Computer graphics development has had a significant impact on many types of media and has revolutionized animation , movies , advertising , and video games , in general. The term computer graphics has been used in

13068-549: The video game industry and impress, until that industry's revenues became comparable to those of movies. Microsoft made a decision to expose DirectX more easily to the independent developer world with the XNA program, but it was not a success. DirectX itself remained a commercial success, however. OpenGL continued to mature as well, and it and DirectX improved greatly; the second-generation shader languages HLSL and GLSL began to be popular in this decade. In scientific computing ,

13189-448: The widespread adoption of normal mapping , bump mapping , and a variety of other techniques allowing the simulation of a great amount of detail. Computer graphics used in films and video games gradually began to be realistic to the point of entering the uncanny valley . CGI movies proliferated, with traditional animated cartoon films like Ice Age and Madagascar as well as numerous Pixar offerings like Finding Nemo dominating

13310-418: The world's primary research center for computer graphics through the 1970s. Also, in 1966, Ivan Sutherland continued to innovate at MIT when he invented the first computer-controlled head-mounted display (HMD). It displayed two separate wireframe images, one for each eye. This allowed the viewer to see the computer scene in stereoscopic 3D . The heavy hardware required for supporting the display and tracker

13431-423: Was almost unknown outside of a research or academic setting.) At around the same time (1961–1962) in the University of Cambridge, Elizabeth Waldram wrote code to display radio-astronomy maps on a cathode ray tube. E. E. Zajac, a scientist at Bell Telephone Laboratory (BTL), created a film called "Simulation of a two-giro gravity attitude control system" in 1963. In this computer-generated film, Zajac showed how

13552-484: Was based on the 16-bit Motorola 68000 microprocessor and AMD bit-slice processors, and had Unix as its operating system. It was targeted squarely at the sophisticated end of the design engineering sector. Artists and graphic designers began to see the personal computer, particularly the Amiga and Macintosh , as a serious design tool, one that could save time and draw more accurately than other methods. The Macintosh remains

13673-409: Was birthed in the 1970s, with the first arcade games using real-time 2D sprite graphics. Pong in 1972 was one of the first hit arcade cabinet games. Speed Race in 1974 featured sprites moving along a vertically scrolling road. Gun Fight in 1975 featured human-looking animated characters, while Space Invaders in 1978 featured a large number of animated figures on screen; both used

13794-493: Was called the Sword of Damocles because of the potential danger if it were to fall upon the wearer. After receiving his Ph.D. from MIT, Sutherland became Director of Information Processing at ARPA (Advanced Research Projects Agency), and later became a professor at Harvard. In 1967 Sutherland was recruited by Evans to join the computer science program at the University of Utah – a development which would turn that department into one of

13915-500: Was developed in 1986 – an important step towards implementing global illumination , which is necessary to pursue photorealism in computer graphics. The continuing popularity of Star Wars and other science fiction franchises were relevant in cinematic CGI at this time, as Lucasfilm and Industrial Light & Magic became known as the "go-to" house by many other studios for topnotch computer graphics in film. Important advances in chroma keying ("bluescreening", etc.) were made for

14036-463: Was developed to realize an image rendering methodology in which each pixel could be parallel processed independently using ray tracing . By developing a new software methodology specifically for high-speed image rendering, LINKS-1 was able to rapidly render highly realistic images." The LINKS-1 was the world's most powerful computer , as of 1984. Also in the field of realistic rendering, the general rendering equation of David Immel and James Kajiya

14157-482: Was drawn and parts that are empty. Although the most basic operation of combining two images is to put one over the other, there are many operations, or blend modes , that are used. The concept of an alpha channel was introduced by Alvy Ray Smith and Ed Catmull in the late 1970s at the New York Institute of Technology Computer Graphics Lab . Bruce A. Wallace derived the same straight over operator based on

14278-432: Was easy to pinpoint exactly where the pen was on the screen at any given moment. Once that was determined, the computer could then draw a cursor at that location. Sutherland seemed to find the perfect solution for many of the graphics problems he faced. Even today, many standards of computer graphics interfaces got their start with this early Sketchpad program. One example of this is in drawing constraints. If one wants to draw

14399-527: Was quick to respond to this interest by releasing the IBM 2250 graphics terminal, the first commercially available graphics computer. Ralph Baer , a supervising engineer at Sanders Associates , came up with a home video game in 1966 that was later licensed to Magnavox and called the Odyssey . While very simplistic, and requiring fairly inexpensive electronic parts, it allowed the player to move points of light around on

14520-560: Was the first GPU, fabricated on a fully integrated NMOS VLSI chip . It supported up to 1024x1024 resolution , and laid the foundations for the emerging PC graphics market. It was used in a number of graphics cards , and was licensed for clones such as the Intel 82720, the first of Intel's graphics processing units . MOS memory also became cheaper in the early 1980s, enabling the development of affordable framebuffer memory, notably video RAM (VRAM) introduced by Texas Instruments (TI) in

14641-522: Was the first graphical standard to be developed. A group of 25 experts of the ACM Special Interest Group SIGGRAPH developed this "conceptual framework". The specifications were published in 1977, and it became a foundation for many future developments in the field. Also in the 1970s, Henri Gouraud , Jim Blinn and Bui Tuong Phong contributed to the foundations of shading in CGI via

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