Term of the Moment
application integration
Definition: graphics
(1) The computer's display system. See display adapter, GPU, discrete graphics, integrated graphics and graphics pipeline.
(2) The creation and manipulation of picture images. All graphics terms in this encyclopedia refer to images and drawings created in the computer. For extremely complex graphics, a fast computer is required, and although mice are widely used for drawing, a digitizer tablet is employed for greater precision (see digitizer tablet and CAD).
Draw, Take a Photo, Scan or Paint
Vector vs. Bitmap
Vector Graphics for CAD and Drawing
Vector graphics comprise a series of points, lines, arcs and other geometric shapes that are created in computer-aided design (CAD) and drawing programs. Each line is a vector, defined as two end points on an x-y matrix. For example, a square is four vectors, one for each side. A circle is many tiny straight lines, the quantity determined by the drawing's resolution. A vector graphics file is entirely a list of vectors.
Vector Graphic Elements Are Easily Scaled
The advantage of vector graphics is that each vector element maintains its own identity and can be selected and manipulated independently of the others. Any single element can be scaled (resized) smaller or larger.
From Vectors to Bitmaps
Monitors display pixels, and printers print dots, both of which are bitmaps. Therefore, to display or print a vector graphics image, it must be converted into bitmaps ("rasterized"). The rasterization process is performed by the operating system and printer language (see page description language).
3D Vector Graphics
Bitmapped Graphics for Imaging and Painting
Bitmapped graphics, also known as "bitmap graphics" and "raster graphics," are like a TV screen. Each image is divided into horizontal rows, and each row is divided into "pixels" (dots). There can be millions of pixels in a single image (see megapixel).
Many Formats, All Digital
Unlike TV, which uses one family of formats for the country, there are dozens of bitmapped graphics and vector graphics formats. See graphics formats and DTV.
Bits Per Pixel
When an image is scanned into the computer or "painted" with a paint program, a bitmap is created in a reserved area of RAM with some number of bits corresponding to each pixel. The simplest monochrome bitmap (black and white) uses one bit (on/off) per pixel. Gray scale bitmaps store a number for each pixel corresponding to a shade of gray; for example, 8 bits holds 254 gray levels plus black and white.
Drawing vs. Painting
Canvas Does Both
Getting Closer All the Time
(2) The creation and manipulation of picture images. All graphics terms in this encyclopedia refer to images and drawings created in the computer. For extremely complex graphics, a fast computer is required, and although mice are widely used for drawing, a digitizer tablet is employed for greater precision (see digitizer tablet and CAD).
The major graphics categories are "vector graphics" and "bitmapped graphics." When pictures are "drawn" (top), they become vector graphics. When they are photographed or scanned, their digital images are bitmaps (a matrix of pixels). Images can also be "painted" (see paint program).
Intricate illustrations can be created with vector graphics drawing programs (top); however, nothing can provide the realism of a photograph or scan (bottom). (Images courtesy of Adobe Systems, Inc.)
Vector graphics comprise a series of points, lines, arcs and other geometric shapes that are created in computer-aided design (CAD) and drawing programs. Each line is a vector, defined as two end points on an x-y matrix. For example, a square is four vectors, one for each side. A circle is many tiny straight lines, the quantity determined by the drawing's resolution. A vector graphics file is entirely a list of vectors.
Vector Graphic Elements Are Easily Scaled
The advantage of vector graphics is that each vector element maintains its own identity and can be selected and manipulated independently of the others. Any single element can be scaled (resized) smaller or larger.
From Vectors to Bitmaps
Monitors display pixels, and printers print dots, both of which are bitmaps. Therefore, to display or print a vector graphics image, it must be converted into bitmaps ("rasterized"). The rasterization process is performed by the operating system and printer language (see page description language).
3D CAD and drawing programs are more complicated than their 2D counterparts because objects are created in a 3D workspace. They can be viewed at any angle by rotating them, whereas in 2D programs, the object would have to be redrawn entirely. Using camera angles and light sources, 3D programs render the drawing with shadows. (Image courtesy of Intergraph Computer Systems.)
Bitmapped graphics, also known as "bitmap graphics" and "raster graphics," are like a TV screen. Each image is divided into horizontal rows, and each row is divided into "pixels" (dots). There can be millions of pixels in a single image (see megapixel).
Many Formats, All Digital
Unlike TV, which uses one family of formats for the country, there are dozens of bitmapped graphics and vector graphics formats. See graphics formats and DTV.
Bits Per Pixel
When an image is scanned into the computer or "painted" with a paint program, a bitmap is created in a reserved area of RAM with some number of bits corresponding to each pixel. The simplest monochrome bitmap (black and white) uses one bit (on/off) per pixel. Gray scale bitmaps store a number for each pixel corresponding to a shade of gray; for example, 8 bits holds 254 gray levels plus black and white.
Although more painting tools are added to drawing programs and more drawing tools are added to paint programs, their inherent structure is different. Drawing programs (vector graphics) allow for the creation of objects that can be manipulated independently. Paint programs (bitmapped graphics) provide a canvas that can be covered with electronic paint.
In one program, Canvas combines tools for drawing (vector graphics) and imaging (bitmapped graphics). The drawing of the PC is vector graphics and Doug Engelbart's mouse in the 1960s is a bitmap (see mouse). The opened Image menu shows some of the bitmap editing tools.
A major goal is to create virtual people who look real, and it took 19 rendering passes to create this lovely lady. In addition, to save space for this example, the original 2.3MB TIFF file was compressed to a 32KB JPEG image (see JPEG and TIFF). (Image courtesy of NVIDIA Corporation.)