Draw distance
Encyclopedia
Draw distance is a computer graphics
Computer graphics
Computer graphics are graphics created using computers and, more generally, the representation and manipulation of image data by a computer with help from specialized software and hardware....

 term, defined as the maximum distance
Distance
Distance is a numerical description of how far apart objects are. In physics or everyday discussion, distance may refer to a physical length, or an estimation based on other criteria . In mathematics, a distance function or metric is a generalization of the concept of physical distance...

 of objects in a three dimensional scene
Three-dimensional space
Three-dimensional space is a geometric 3-parameters model of the physical universe in which we live. These three dimensions are commonly called length, width, and depth , although any three directions can be chosen, provided that they do not lie in the same plane.In physics and mathematics, a...

 that are drawn by the rendering engine
Rendering (computer graphics)
Rendering is the process of generating an image from a model , by means of computer programs. A scene file contains objects in a strictly defined language or data structure; it would contain geometry, viewpoint, texture, lighting, and shading information as a description of the virtual scene...

. Polygons
Polygon (computer graphics)
Polygons are used in computer graphics to compose images that are three-dimensional in appearance. Usually triangular, polygons arise when an object's surface is modeled, vertices are selected, and the object is rendered in a wire frame model. This is quicker to display than a shaded model; thus...

 that lie behind the draw distance won't be drawn to the screen.

As the draw distance increases more distant polygons need to be drawn onto the screen that would regularly be clipped
Clipping (computer graphics)
Any procedure which identifies that portion of a picture which is either inside or outside a picture is referred to as a clipping algorithm or clipping.The region against which an object is to be clipped is called clipping window.-Examples:...

. This requires more computing power. This means the graphic quality and realism of the scene will increase as draw distance increases, but the overall performance (frames per second
Frame rate
Frame rate is the frequency at which an imaging device produces unique consecutive images called frames. The term applies equally well to computer graphics, video cameras, film cameras, and motion capture systems...

) will decrease. Many games and applications will allow users to manually set the draw distance to balance performance and visuals.

Problems in older games

Older games had far shorter draw distances, most noticeable in vast, open scenes. Racing
Racing game
A racing video game is a genre of video games, either in the first-person or third-person perspective, in which the player partakes in a racing competition with any type of land, air, or sea vehicles. They may be based on anything from real-world racing leagues to entirely fantastical settings...

 arcade game
Arcade game
An arcade game is a coin-operated entertainment machine, usually installed in public businesses such as restaurants, bars, and amusement arcades. Most arcade games are video games, pinball machines, electro-mechanical games, redemption games, and merchandisers...

s were particularly infamous, as the open highways and roads often led to "pop-up graphics" - an effect where distant objects suddenly appear without warning as the camera gets closer to it. This is a hallmark of poor draw distance, and still plagues large, open-ended games like the Grand Theft Auto
Grand Theft Auto (series)
Grand Theft Auto is a multi-award-winning British video game series created in the United Kingdom by Dave Jones, then later by brothers Dan Houser and Sam Houser, and game designer Zachary Clarke. It is primarily developed by Edinburgh based Rockstar North and published by Rockstar Games...

series and Second Life
Second Life
Second Life is an online virtual world developed by Linden Lab. It was launched on June 23, 2003. A number of free client programs, or Viewers, enable Second Life users, called Residents, to interact with each other through avatars...

.

Alternatives

A common trick used in games to disguise a short draw distance is to obscure the area with a distance fog
Distance fog
Distance fog is a technique used in 3D computer graphics to enhance the perception of distance by simulating fog.Because many of the shapes in graphical environments are relatively simple, and complex shadows are difficult to render, many graphics engines employ a "fog" gradient so objects further...

. Alternative methods have been developed to sidestep the problem altogether using level of detail manipulation. Black & White was one of the earlier games to use adaptive level of detail to decrease the number of polygons in objects as they moved away from the camera, allowing it to have a massive draw distance while maintaining detail in close-up views.

The Legend of Zelda: The Wind Waker
The Legend of Zelda: The Wind Waker
The Legend of Zelda: The Wind Waker, released as in Japan, is an action-adventure game and the tenth installment in The Legend of Zelda series. It was released for the Nintendo GameCube in Japan on December 13, 2002, in North America on March 24, 2003, in Europe on May 2, 2003, and in Australia on...

uses a variant of the level of detail programming mentioned above. The game overworld is divided into 49 squares. Each square has an island inside of it; the distance between the island and the borders of the square are considerable. Everything within a square is loaded when entered, including all models used in close-up views and animations. Utilizing the telescope item, one can see just how detailed even far away areas are. However, textures are not displayed; they are faded in as one gets closer to the square's island-this may actually be an aesthetic effect and not to free up system resources. Islands outside of the current square are less detailed-however, these far-away island models do not degenerate any further than that, even though some of these islands can be seen from everywhere else in the overworld. In both indoor and outdoor areas, there is no distance fog-however, there are some areas where "distance" fog is used as an atmospheric effect. As a consequence to the developers' excessive attention to detail, however, some areas of the game have lower framerates due to the large amount of enemies on screen.

Grand Theft Auto III
Grand Theft Auto III
Grand Theft Auto III is a 2001 open world action computer and video game developed by DMA Design in the United Kingdom, and published by Rockstar Games. It is the first 3D title in the Grand Theft Auto series. It was released in October 2001 for the PlayStation 2, May 2002 for Microsoft Windows,...

made particular use of fogging, however, this made the game less playable when driving or flying at high speed, as objects would pop-up out of the fog and cause the player to crash into them.

Halo 3
Halo 3
Halo 3 is a first-person shooter video game developed by Bungie for the Xbox 360 console. The third installment in the Halo franchise, the game concludes the story arc begun in Halo: Combat Evolved and continued in Halo 2...

is claimed by its creators at Bungie Studios to have a draw distance upwards of 14 miles. This is an example of the vastly improved draw distances made able by more recent game consoles. In addition, Crysis
Crysis
Crysis is a science fiction first-person shooter video game developed by Crytek , published by Electronic Arts for Microsoft Windows, and released in November 2007. It is the first game of a trilogy. A separate game entitled Crysis Warhead was released on September 12, 2008, and follows similar...

is said to have a draw distance up to 16 kilometres (9.9 mi), while Cube 2: Sauerbraten, has a potentially unlimited draw distance, possibly due to the larger map size.

External links

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