Vector graphics use of lines, curves, points, shapes and polygons to represent images and computer graphics. While raster graphics are an array of pixels arranged to form a shape, vector graphics are algorithm-based designs.
Digital images are composed of pixels. When more pixels are contained within the image, and the smaller and closer together those pixels are, the image quality is higher. When there are more pixels, and the image quality is higher, the file size becomes larger. However, if the image is enlarged, the number of pixels remains constant and the size of each pixel is increased, making the image appear pixelated, or blurry.
"Vector graphics files store the lines, shapes and colors that make up an image as mathematical formula. A vector graphics program uses these mathematical formulae to construct the screen image, building the best quality image possible, given the screen resolution. The mathematical formulae determine where the dots that make up the image should be placed for the best results when displaying the image. Since these formulae can produce an image scalable to any size and detail, the quality of the image is only determined by the resolution of the display, and the file size of vector data generating the image stays the same. Printing the image to paper will usually give a sharper, higher resolution output than printing it to the screen but can use exactly the same vector data file."
Advantages of vector graphics over raster graphics:
• Minimal amounts of information translate to a much smaller file size compared to large raster images (the size of representation doesn't depend on the dimensions of the object), though a vector graphic with a small file size is often said to lack detail compared with a real world photo.
• Correspondingly, one can indefinitely zoom in on e.g. a circle arc, and it remains smooth. On the other hand, a polygon representing a curve will reveal that it is not really curved.
• On zooming in, lines and curves need not get wider proportionally. Often the width is either not increased or less than proportional. On the other hand, irregular curves represented by simple geometric shapes may be made proportionally wider when zooming in, to keep them looking smooth and not like these geometric shapes.
• The parameters of objects are stored and can be later modified. This means that moving, scaling, rotating, filling etc. doesn't degrade the quality of a drawing. Moreover, it is usual to specify the dimensions in device-independent units, which results in the best possible rasterization on raster devices.
• From a 3-D perspective, rendering shadows is also much more realistic with vector graphics, as shadows can be abstracted into the rays of light from which they are formed. This allows for photo realistic images and renderings.
|Editors||Tyson Barlow, David Burchfield|