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While Graphic Design as a discipline has a relatively recent history, graphic design-like activities span the history of humankind: from the caves of Lascaux, to Rome’s Trajan’s Column to the illuminated manuscripts of the Middle Ages, to the dazzling neons of Ginza. In both this lengthy history and in the relatively recent explosion of visual communication in the 20th and 21st centuries, there is sometimes a blurring distinction and over-lapping of advertising art, graphic design and fine art. After all, they share many of the same elements, theories, principles, practices and languages, and sometimes the same benefactor or client. In advertising art the ultimate objective is the sale of goods and services. In graphic design, “the essence is to give order to information, form to ideas, expression and feeling to artifacts that document human experience.

Hundreds of graphic designs of animals by the primitive people in the Chauvet Cave, in the south of France,which were drawn more than 30,000 B.C, as well as similar designs in the Lascaux cave of France that were drawn more than 14,000 B.C., or the designs of the primitive hunters in the Bhimbetka rock shelters in India that were drawn more than 7,000 B.C., and the Aboriginal Rock Art, in the Kakadu National Park of Australia, and many other rock or cave paintings in other parts of the world show that graphics have a very long history which is shared among humanity. This history together with the history of writing which was emerged in 3000-4000 B.C. are at the foundation of the Graphic Art.

Rock and cave art

The term “rock art” appears in the published literature as early as the 1940s . It has also been described as “rock carvings”, “rock drawings”, “rock engravings”, “rock inscriptions”, “rock paintings”, “rock pictures”, “rock records” , “rock sculptures.

Both petroglyphs and pictographs can be parietal, meaning on the walls of a cave or rock shelter, open-air (meaning they are made on exposed natural outcrops) or monument-based which are made on stones consciously deposited.

The earliest evidence of painting derives from archaeological sites in two rock-shelters in Arnhem Land, in northern Australia. In the lowest layer of material at these sites there are used pieces of ochre estimated to be 60,000 years old. Archaeologists have also found a fragment of rock painting preserved in a limestone rock-shelter in the Kimberley region of North-Western Australia dated at 40 000 years old. Pigments from the “Bradshaw paintings” of the Kimberley are so old they have become part of the rock itself, making carbon dating impossible. Some experts suggest that these paintings are in the vicinity of 50,000 years old and may even pre-date aboriginal settlement.

Petroglyphs are created by rock removal, including scratching, abrading, pecking, carving, drilling, incising and sculpting. Locations of choice are rock facets coated with patina, a dark mineral accumulation on rock surfaces. Petroglyphs remove the patina, exposing the contrasting lighter rock interior. Instances of negative images, produced by removing the patina surrounding the intended figure, are also known. Sometimes petroglyphs are painted or accentuated by polishing. The degree of repatination indicates relative dating. Some of the most ancient petroglyphs are the same color as the surrounding rock.

Cave paintings are paintings on cave walls and ceilings, and the term is used especially for those dating to prehistoric times. The earliest known European cave paintings date to Aurignacian, some 32,000 years ago. The purpose of the paleolithic cave paintings is not known. The evidence suggests that they were not merely decorations of living areas, since the caves in which they have been found do not have signs of ongoing habitation. Also, they are often in areas of caves that are not easily accessed. Some theories hold that they may have been a way of communicating with others, while other theories ascribe them a religious or ceremonial purpose.

The most common themes in cave paintings are large wild animals, such as bison, horses, aurochs, and deer, and tracings of human hands as well as abstract patterns, called finger flutings. Drawings of humans were rare and are usually schematic rather than the more naturalistic animal subjects. One explanation for this is that realistically painting the human form was forbidden by a powerful religious taboo. Cave art may have begun in the Aurignacian period (Hohle Fels, Germany), but reached its apogee in the late Magdalenian (Lascaux, France).

Henri Breuil interpreted the paintings as being hunting magic, meant to increase the number of animals. As there are some clay sculptures that seem to have been the targets of spears, this may partly be true, but does not explain the pictures of predators such as the lion or the bear.

An alternative theory, developed by David Lewis-Williams and broadly based on ethnographic studies of contemporary hunter-gatherer societies, is that the paintings were made by Cro-Magnon shamans. The shaman would retreat into the darkness of the caves, enter into a trance state and then paint images of their visions, perhaps with some notion of drawing power out of the cave walls themselves. This goes some way toward explaining the remoteness of some of the paintings (which often occur in deep or small caves) and the variety of subject matter (from prey animals to predators and human hand-prints).

Lascaux is the setting of a complex of caves in southwestern France famous for its Paleolithic cave paintings. The original caves are located near the village of Montignac, in the Dordogne département. They contain some of the best-known Upper Paleolithic art. These paintings are estimated to be 16,000 years old. They primarily consist of realistic images of large animals, most of which are known from fossil evidence to have lived in the area at the time. In 1979, Lascaux was added to the UNESCO World Heritage Sites list along with other prehistoric sites in the Vézère valley.

The cave was discovered on September 12, 1940 by four teenagers, Marcel Ravidat, Jacques Marsal, Georges Agnel, and Simon Coencas, as well as Marcel’s dog, Robot. The cave complex was opened to the public in 1948. By 1955, the carbon dioxide produced by 1,200 visitors per day had visibly damaged the paintings. The cave was closed to the public in 1963 in order to preserve the art. After the cave was closed, the paintings were restored to their original state, and were monitored on a daily basis. Rooms in the cave include The Great Hall of the Bulls, the Lateral Passage, the Shaft of the Dead Man, the Chamber of Engravings, the Painted Gallery, and the Chamber of Felines.

Vector graphics is the use of geometrical primitives such as points, lines, curves, and shapes or polygon(s), which are all based on mathematical equations, to represent images in computer graphics.

Vector graphics formats are complementary to raster graphics, which is the representation of images as an array of pixels, as it is typically used for the representation of photographic images.[1] There are instances when working with vector tools and formats is the best practice, and instances when working with raster tools and formats is the best practice. There are times when both formats come together. An understanding of the advantages and limitations of each technology and the relationship between them is most likely to result in efficient and effective use of tools.

Overview

Computer displays are made up from grids of small rectangular cells called pixels. The picture is built up from these cells. The smaller and closer the cells are together, the better the quality of the image, but the bigger the file needed to store the data. If the number of pixels is kept constant, the size of each pixel will grow and the image becomes grainy (pixellated) when magnified, as the resolution of the eye enables it to pick out individual pixels.

Vector graphics files store the lines, shapes and colours that make up an image as mathematical formulae. 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.

Editing vector graphics

Vector graphic drawing software is used for creating and editing vector graphics. The image can be changed by editing screen objects which are then saved as modifications to the mathematical formulae. Mathematical operators in the software can be used to stretch, twist, and colour component objects in the picture or the whole picture, and these tools are presented to the user intuitively through the graphical user interface of the computer. It is possible to save the screen image produced as a bitmap/raster file or generate a bitmap of any resolution from the vector file for use on any device.

The size of the file generated will depend on the resolution required, but the size of the vector file generating the bitmap/raster file will always remain the same. Thus, it is easy to convert from a vector file to a range of bitmap/raster file formats but it is much more difficult to go in the opposite direction, especially if subsequent editing of the vector picture is required. It might be an advantage to save an image created from a vector source file as a bitmap/raster format, because different systems have different (and incompatible) vector formats, and some might not support vector graphics at all. However, once a file is converted from the vector format, it is likely to be bigger, and it loses the advantage of scalability without loss of resolution. It will also no longer be possible to edit individual parts of the image as discrete objects.The file size of vector graphic depends on the number of graphic elements it contains.

Vector formats are not always appropriate in graphics work. For example, digital devices such as cameras and scanners produce raster graphics that are impractical to convert into vectors, and so for this type of work, the editor will operate on the pixels rather than on drawing objects defined by mathematical formulae. Comprehensive graphics tools will combine images from vector and raster sources, and may provide editing tools for both, since some parts of an image could come from a camera source, and others could have been drawn using vector tools.

Typical primitive objects

* Lines and polylines
* Polygons
* Circles and ellipses
* Bézier curves
* Bezigons
* Text (in computer font formats such as TrueType where each letter is created from Bézier curves)

This list is not complete. There are various types of curves (Catmull-Rom splines, NURBS etc.), which are useful in certain applications.

Often, a bitmap image is considered as a primitive object. From the conceptual view, it behaves as a rectangle.

Vector operations

Vector graphics editors typically allow rotation, movement, mirroring, stretching, skewing, affine transformations, changing of z-order and combination of primitives into more complex objects.

More sophisticated transformations include set not operations on closed shapes (union, difference, intersection, etc.).

Vector graphics are ideal for simple or composite drawings that need to be device-independent, or do not need to achieve photo-realism. For example, the PostScript and PDF page description languages use a vector graphics model.

Printing

Vector art is key for printing. Since the art is made from a series of mathematical curves it will print very crisply even when resized. For instance, one can print a vector logo on a small sheet of copy paper, and then enlarge the same vector logo to billboard size and keep the same crisp quality. A low-resolution raster graphic would blur or pixelate excessively if it were enlarged from business card size to billboard size.

If we regard typographic characters as images, then the same considerations that we have made for graphics apply even to composition of written text for printing (typesetting). Older character sets were stored as bitmaps, therefore to achieve maximum print quality they had to be used at a given resolution only; these font formats are said to be non-scalable. High quality typography is nowadays based on character drawings (fonts) which are typically stored as vector graphics, and as such are scalable to any size. Examples of these vector formats for characters are Postscript fonts and TrueType fonts.

Vector Illustration

Vector illustration is a popular technique of many digital illustrators worldwide. Some of the greatest internationally acclaimed artists in the field are Jon Burgerman, Catalina Estrada, Petra Stefankova, Nathan Jurevicius, J. Otto Seibold, Leo Blanchette and others.

Example showing effect of vector graphics versus raster graphics. The original vector-based illustration is at the left. The upper-right image illustrates magnification of 7x as a vector image. The lower-right image illustrates the same magnification as a bitmap image. Raster images are based on pixels and thus scale with loss of clarity, while vector-based images can be scaled indefinitely without degrading quality.

One example of vector graphics format is SVG (Scalable Vector Graphics), an open standard created and developed by the World Wide Web Consortium to address the need (and attempts of several corporations) for a versatile, scriptable and all-purpose vector format for the web and otherwise. Another example is VML, a proposed standard that was adopted by Microsoft. Arguably, the AI format, the native format for Adobe Illustrator, is also standard in vector graphics.

The SWF Adobe’s (fomerly Macromedia’s) file format, is also a vector based container used to store animation. Web pages created in Flash can be enlarged to fit any monitor size while retaining the same graphic quality.

3D modelling

In 3D computer graphics, vectorized surface representations are most common (bitmaps can be used for special purposes such as surface texturing, height-field data and bump mapping). At the low-end, simple meshes of polygons are used to represent geometric detail in applications where interactive frame rates or simplicity are important. At the high-end, where one is willing to trade-off higher rendering times for increased image quality and precision, smooth surface representations such as Bézier patches, NURBS or Subdivision surfaces are used. One can, however, achieve a smooth surface rendering from a polygonal mesh through the use of shading algorithms such as Phong and Gouraud.

The word “raster” has its origins in the Latin rastrum (a rake), which is derived from radere (to scrape), and was originally used in the raster scan of cathode ray tubes (CRT), which paint the image line by line; it is used for a grid of pixels by generalization.

In computer graphics, a raster graphics image or bitmap is a data structure representing a generally rectangular 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 (see Comparison of graphics file formats).

A bitmap corresponds bit-for-bit with an image displayed on a screen, generally in the same format used for storage in the display’s 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”) and refer to vector graphics as “line work”.

Resolution

Raster graphics are resolution dependent. They cannot scale up to an arbitrary resolution without loss of apparent quality. This property contrasts with the capabilities of vector graphics, which easily scale up to the quality of the device rendering them. Raster graphics deal more practically than vector graphics with photographs and photo-realistic images, while vector graphics often serve better for typesetting or for graphic design. Modern computer-monitors typically display about 72 to 130 pixels per inch (PPI), and some modern consumer printers can resolve 2400 dots per inch (DPI) or more; determining the most appropriate image resolution for a given printer-resolution can pose difficulties, since printed output may have a greater level of detail than a viewer can discern on a monitor. Typically, a resolution of 150 to 300 pixel per inch works well for 4-color process (CMYK) printing.

Raster-based image editors

Raster-based image editors, such as Photoshop, MS Paint, and GIMP, revolve around editing pixels, unlike vector-based image editors, such as CorelDRAW, Adobe Illustrator, or Inkscape, which revolve around editing lines and shapes (vectors). When an image is rendered in a raster-based image editor, the image is composed of millions of pixels. At its core, a raster image editor works by manipulating each individual pixel. Most pixel-based image editors work using the RGB color model, but some also allow the use of other color models such as the CMYK color model.

The smiley face in the top left corner is a bitmap image. When enlarged, individual pixels appear as squares. Zooming in further, they can be analyzed, with their colors constructed by adding the values for red, green and blue.

Digital painting thrives mostly in production art. It is most widely used in conceptual design for film, television and video games. Digital painting software such as Corel Painter, Adobe Photoshop, ArtRage, GIMP, and openCanvas give artists a similar environment to a physical painter: a canvas, painting tools, mixing palettes, and a multitude of color options. There are various types of digital painting, including impressionism, realism, and watercolor. There are both benefits and drawbacks of digital painting. While digital painting allows the artist the ease of working in an organized, mess-free environment, some argue there will always be more control for an artist holding a physical brush in their hand. Some artists believe there is something missing from digital painting, such as the character that is unique to every physically made object. Many artist post blogs and comment on the various differences between digitally created work and traditionally created artwork.