Sprite (video games)

Set sprites.

Sprites were popularized by Jay Miner. It is a type of bitmap drawn on the computer screen by specialized graphics hardware (MSX, Atari 400/800, Commodore 64 and Commodore Amiga were some of the few computers that supported real sprites) without additional CPU calculations. They are often small and partially transparent, thus allowing them to assume other shapes than the rectangle, for example the mouse pointer on Amiga series computers. This is possible since a logical OR or AND operation could be done between the original image and another, and leave the result in another memory location. This way it was easy to change colors or remove the background using a "mask". Typically, sprites are used in video games to create the graphics of For example, the characters in a Pac-Man could be sprites. They are generally used to produce an animation, such as a running character, some facial expression, or a body movement.

Over time the use of this term was extended to any small bitmap that is drawn on the screen, even if it has to move the whole mainframe and doesn't have specialized hardware. This causes that, unlike computers that support real sprites, resolutions cannot be mixed (for example, displaying a 256-color, high-resolution sprite on a 16-color, low-resolution screen), the cpu has to calculate the transparency and they are not synchronized. with vertical screen refresh (so graphics hardware that doesn't have real sprites needs to apply double buffering techniques).

Sprites have evolved throughout the history of video games. At first, while some were computer generated, others were drawn by hand to be later transferred to the computer.

The video game Mortal Kombat was the first to produce fully digitized sprites in a game, where actors were photographed to make each character animation.^{[citation needed]}

With the advent of 3D video games, the use of sprites has begun to be put aside, by occupying polygonal characters.

It is possible to reuse a sprite when it is fully drawn on the next line, making the effective number of sprites greater than the initial number of sprites. It is also possible to use the Blitter to simulate more sprites or the Copper to modify its color palette.

A series of images joined in the same file next to each other and representing the same character (or object) in different positions is also called a sprite. Unlike an animated GIF, all images are visible at the same time and may be encoded in a lighter image format (usually PNG). This is mainly used in mobile phone games in J2ME format, since the time to load an image is much longer than it takes to select and display an area of an image already loaded into memory. It is also used in the design of skins for software in order to reduce the number of files in the package that contains them.

Synonyms and others

Most game companies rarely use the term "sprite" to refer to this type of graphics. Other alternative names that have been used are:

• Charts Player-Proyectil: The player-proyectil graphics name Player-Missile Graphics) was used in the Atari 400/800 XL/XE microcomputers, and in the first game machines operated with coins of the same brand, to refer to the sprite graphics generated by hardware. The term reflected the use of two types of graphic objects, "players", and other objects ("proyectiles"). They had a limited horizontal resolution (8 or 2 pixels, although they could scale and potentially use 192 vertical resolution lines).
• Movable Object Block or MOB: it was used in the literature of the graphics on MOS Technology chips (data sheets, etc.). However, Commodore, the main user of MOS chips, who was also the owner of MOS for a long time, used the term "sprite".
• OBJ: In the Nintendo, Super Nintendo and Game Boy video consoles, the "sprites" were called OBJS (apope of "objects"), and the RAM region used to store the attributes and coordinates of the "sprites" was known as "OAM" (Memory of Object Attributesin English Objects Attribute Memory). This applies even today in Nintendo 3DS games.
• BOB u Blitter objects (Blitter Objects): It was a popular name for graphic objects drawn by the dedicated graphic coprocessor Blitter in the Amiga computer series. This machine also had real hardware sprites. The DarkBASIC programming language used the term "Bob" to refer to its sprites management functions by software, before being changed to the term "sprite", used more conventionally.
• Sprites by software or Software sprites: So they referred to the subroutines that used the technique of transferring bit blocks (in English) bit-blitting) to achieve the same goal in systems like Atari ST and Apple II whose graphic hardware did not have the ability to handle true "sprite".
• 3D Sprite: It is a term that is often used to refer to the "sprites" that are essentially 3D facets with texture maps that always have their normal surface facing the camera.
• Z-Sprite: It is a term often used for 3D environments that contain only "sprites". The Z parameter provides a scalar effect that creates the illusion of depth. For example, in adventure games like King's Quest VI, where the camera never moves, it would be enough with normal 2D sprites, but the sprites-Z give it an extra touch.
• Impostor: It is a term used instead of "billboard" if the Billboard is used to subreptically replace a real 3D object. "Billboard" is a texture used in the "billboarding" process. In turn this is a 3D graphical method in which different alpha values are assigned to individual parts of a texture.