GRAPHICS HARDWARE (INPUT DEVICES)

COMPUTER GRAPHICS

The use of a computer to produce and manipulate pictorial images on a video screen, as in animation techniques or the production of audio visual aids

The term computer graphics includes almost everything on computers that is not text or sound. Today almost every computer can do some graphics, and people have even come to expect to control their computer through icons and pictures rather than just by typing.

EXAMPLES OF COMPUTER GRAPHICS

GRAPHICS HARDWARE

Creating and editing computer graphics requires specialized software and high-performance hardware,

Graphics hardware is both for input and output.

hardware which allows graphical information to be entered directly to the system, Those hardware are called Graphics Input Hardware.

Locators are the devices which gives position information. The computer receives from a

locator the coordinates for a point using a locator we can indicate a position on the screen.

Locators

Joystick

TabletMouse

JOYSTICK

A joystick has two potentiometers, they have been attached to a single lever.

Moving the lever forward or backward changes the setting on one potentiometer.

MOUSE

An input device that enables you to edit and manipulate images. For example in terms of computer graphics, the mouse can be used to crop an image or to use the magic wand tool etc.

TABLET

A tablet composed of a flat surface and a pen like stylus or like tablet cursor

The tablet is able to sense the position of the stylus.

Selector devices are used to select a particular graphical object a selector may pick particular item

but provide no information about that item is located on the screen.

LIGHT PEN

An input device that allows you to draw on a screen with greater positional accuracy, similarly to how you would on a graphics tablet it can also be used to point at displayed objects

KEYBOARDSThe keyboard is an efficient device for inputting such non graphic data. Cursor control keys and function keys are common features on general purpose keyboards. Additional a numeric keyboard is often included on the keyboard for fast entry of numeric data.

TRACK BALLS The track ball are an input device which is usually used with CAD workstations. Trackballs are used to accurately draw on the computer trackballs and spaceballs are mainly seen or used for games.

SCANNERS

An input device that allows you to scan in images posters photographs etc. which can then be uploaded and edited in a graphic software package

TOUCH PANELS

Touch panels allow displayed objects or screen positions to be selected with the touch of a finger.