Vector Graphics Essay Example for Free

Vector Graphics Essay Vector graphics is the use of geometrical primitives such as points, lines, curves, and shapes or polygon(s), which are all based on mathematical expressions, to represent images in computer graphics. Vector, in this context, implies more than a straight line. Vector graphics are based on images made up of vectors (also called paths, or strokes) which lead through locations called control points. Each of these points has a definite position on the x and y axes of the work plan. Each point, as well, is a variety of database, including the location of the point in the work space and the direction of the vector (which is what defines the direction of the track). Each track can be assigned a color, a shape, a thickness and also a fill. This does not affect the size of the files in a substantial way because all information resides in the structure; it describes how to draw the vector. Same as object-oriented graphics, refers to software and hardware that use geometrical formulas to represent images. The other method for representing graphical images is through bit maps, in which the image is composed of a pattern of dots. This is sometimes called raster graphics. Programs that enable you to create and manipulate vector graphics are called draw programs, whereas programs that manipulated bit-mapped images are called paint programs. Vector-oriented images are more flexible than bit maps because they can be resized and stretched. In addition, images stored as vectors look better ondevices (monitors and printers) with higher resolution, whereas bit-mapped images always appear the same regardless of a devices resolution. Another advantage of vector graphics is that representations of images often require less memory than bit-mapped images do. Almost all sophisticated graphics systems, including CADD systems andanimation software, use vector graphics. In addition, many printers (PostScriptprinters, for example) use vector graphics. Fonts represented as vectors are called vector fonts, scalable fonts, object-oriented fonts, and outline fonts. Note that most output devices, including dot-matrix printers, laser printers, and display monitors, are raster devices (plotters are the notable exception). This means that all objects, even vector objects, must be translated into bit maps before being output. The difference between vector graphics and raster graphics, therefore, is that vector graphics are not translated into bit maps until the last possible moment, after all sizes and resolutions have been specified. PostScript printers, for example, have a raster image processor (RIP) that performs the translation within the printer. In their vector form, therefore, graphics representations can potentially be output on any device, with any resolution, and at any size. Raster Graphics In computer graphics, a raster graphics image, or bitmap, is a dot matrix data structure representing a generallyrectangular grid of pixels, or points of color, viewable via a monitor, paper, or other display medium. Raster images are stored in image files with varying formats A bitmap corresponds bit-for-bit with an image displayed on a screen, generally in the same format used for storage in the displays video memory, or maybe as a device-independent bitmap. A bitmap is technically characterized by the width and height of the image in pixels and by the number of bits per pixel (a color depth, which determines the number of colors it can represent). The printing and prepress industries know raster graphics as contones (from continuous tones). The opposite to contones is line work, usually implemented as vector graphics in digital systems. What is the difference between vector and raster graphics? Answer: The difference between vector and raster graphics is that raster graphics are composed of pixels, while vector graphics are composed of paths. A raster graphic, such as a gif or jpeg, is an array of pixels of various colors, which together form an image. A vector graphic, such as an . eps file or Adobe Illustrator? file, is composed of paths, or lines, that are either straight or curved. The data file for a vector image contains the points where the paths start and end, how much the paths curve, and the colors that either border or fill the paths. Because vector graphics are not made of pixels, the images can be scaled to be very large without losing quality. Raster graphics, on the other hand, become blocky, since each pixel increases in size as the image is made larger. This is why logos and other designs are typically created in vector format the quality will look the same on a business card as it will on a billboard. Vector Graphics typically are generated using drawing or illustration programs (e. g. , Adobe Illustrator) and are composed of mathematically-defined geometric shapes—lines, objects and fills. Since vectors entail both magnitude and direction, vector elements thus are comprised of line segments whose length represents magnitude and whose orientation in space represents direction. Vector graphics usually are easily modified within the creating application and generally are not affected detrimentally by scaling (enlarging or reducing their size). Because vector elements are mathematically-defined, scaling simply requires modification of their mathematical locations. However, vector files do not support photographic imagery well and often can be problematic for cross-platform exchange. Vector graphics typically are saved as EPS format. This makes vector graphics ideal for logo design. Creating a vector logo is more difficult but the effort pays for itself when the vector logo file is sent to printers or sign makers etc. The vector logo can be scaled up or down with out losing quality and would enable smooth transition between various media. Raster Graphic Images are produced by digital image capture devices: digital scanners or digital cameras, or by pixel editing programs (e. g. , Adobe Photoshop). Raster images are composed of a matrix (grid) or bitmap of digital picture elements (pixels). Pixels are squares or rectangles described as black, white, gray or color. Raster images typically are saved as TIFF format, but can be saved as EPS as well. Whereas conversion from vector to raster is easily accomplished, raster conversion to vector is much more difficult (and often is not possible). Raster images typically are easily shared across various platforms, but can be more difficult than vector graphics to modify. As well, raster graphics are impacted by scaling. Creating a raster logo design using Adobe Photoshop might be ideal for web only usage but if you are serious about branding, then the resulting raster PSD logo file will be of limited use. When sent to a printer or sign maker and when they try to scale the raster logo, the quality deteriorates and pixellation occurs. Yes, agreed, creating the raster logo design in Photoshop would enable a designer to pile on stunning effects (such as drop shadows, beveling, blurring etc). But the final deliverable will have limited uses.