|This article does not cite any references or sources. (May 2012)|
Draw distance, also known as render distance, is a computer graphics term, defined as the maximum distance of objects in a three-dimensional scene that are drawn by the rendering engine. Polygons that lie beyond the draw distance will not 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. This requires more computing power; the graphic quality and realism of the scene will increase as draw distance increases, but the overall performance (frames per second) 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 arcade games were particularly infamous, as the open highways and roads often led to "pop-up graphics", or "pop-in" – an effect where distant objects suddenly appear without warning as the camera gets closer to them. This is a hallmark of short draw distance, and still plagues large, open-ended games like the Grand Theft Auto series and Second Life. Formula 1 97 offered a setting so the player could choose between fixed draw distance (with variable frame rate) and fixed frame rate (with variable draw distance).
A common trick used in games to disguise a short draw distance is to obscure the area with a distance fog. 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 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 distances 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' attention to detail, however, some areas of the game have lower frame rates due to the large number of enemies on screen.
Grand Theft Auto III 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 is claimed by its creators at Bungie Studios to have a draw distance upwards of 14 miles, which is an example of the vastly improved draw distances made able by more recent game consoles. In addition, Crysis is said to have a draw distance up to 16 kilometers (9.9 mi), while Cube 2: Sauerbraten, has a potentially unlimited draw distance, possibly due to the larger map size. Grand Theft Auto V was praised for its seemingly infinite draw distance despite having a large, detailed map.