Computer Font
Usually a font in the computer is a data file containing a set of glyphs/ characters, or symbols. The term font once referred to interchangeable typefaces using mechanical components but, at the present time most modern fonts are used in computing. There are three basic kinds of computer font formats are available presently:
1 Bitmap font format – this font format consists of a series of dots or pixels representing the image of each glyph in each of the font face and font size.
2 Outline font format – this font format extensively uses the Bézier curves, drawing instructions and algorithms to express each character, which make the single character outline scalable to any size.
3 Stroke font format – this font format uses a sequence of particular lines and supplementary information to characterize the outline, or size and shape of the line in a particular type face and type size, which together describes the appearance of the character.
The bitmap type of fonts is quite fast and easy to use in a computer code, but these fonts are inflexible, requiring a separate set of font images for each size and each typeface. On the other hand outline and stroke fonts can be resized easily using a particular font and substituting different measurements for components of each character, but, these font formats are somewhat more complicated to use as compared to the bitmap fonts as they require additional computer code to render them properly on the monitor.
The main difference between the bitmap fonts and outline fonts is the use of two main types of image file formats by these font formats. Bitmap image formats usually stores the image data as a grid of pixels, many times with compression. On the other hand outline or stroke font formats usually store the commands for drawing the character image instead of storing the image itself. A bitmap image can be displayed in a different size with some distortion in the image quality, but it is displayed quickly on the computer monitor on the other hand outline or stroke image formats are resizable and requires least effort for that but simultaneously it takes more time to get displayed as the pixels are drawn from scratch every time they are displayed on the computer monitor.
Fonts can be designed and new ones are created through font editors. Fonts particularly designed for the computer screen display purpose and not for printing are termed as the screen fonts.
== Font types ==
For the benefit of the readers we are trying to describe each of the font type in detail here below:
=== Bitmap fonts ===
In a bitmap font each character is stored as an array of pixels. Usually the bitmap fonts are assortments of pixel images of characters. For each variant of the font, you require a complete set of character images, with each set containing an image for each character. Suppose a font has three sizes, and combination of bold and italic, then you should have 12 complete sets of images for the characters and symbols of that particular font.
The salient features of the bitmap fonts are:These are very fast and simple to for displayUnscaled bitmap fonts always produces exactly the same outputThey are much easier to create as compared to other kind of fonts
The major weakness of bitmap font is that the visual quality of the font has a tendency to be of poor quality when it is scaled or transformed. The earlier bitmap fonts were available only in some optimized sizes. In the earlier days the computer systems only used bitmap fonts due to constraints in their processing power and memory. Now presently the recent improvements in hardware scenario has allowed the bitmap fonts to be replaced with outline or stroke fonts where arbitrary scaling is desirable, but bitmap fonts are still in common use in embedded systems and where speed and simplicity are considered important.
Presently the bitmap fonts are used in the Linux console, the Windows recovery console, and embedded systems. Older dot matrix printers used bitmap fonts. To draw a sequence using a bitmap font means to sequentially output bitmaps of each character that the string comprises, performing per-character serration. Bitmap fonts can be mono-spaced or proportional.
The bitmap fonts may use monochrome or shades of gray. While displaying a text, typically an operating system properly represents the shades of gray as intermediate colors between the color of the font and that of the background. However, the text is represented as an image with transparent background.
The bitmap fonts displayed best at their own pixel size. Some of the computer systems using bitmap fonts are capable of creating font variants algorithmically. The advanced computer systems perform anti-aliasing on bitmap fonts whose size does not match the size that the particular application requests. This technique works well for making the font size smaller but not able to increase the font size.
=== Outline fonts ===
Outline fonts are also known as the vector fonts often, actually these are collections of vector images, to be more precise a set of lines and curves to define the border of a character. The advent of desktop publishing systems brought the need for a general standard to incorporate the graphical user interface of the first Macintosh and laser printers and the standard introduced was Adobe PostScript.
The major advantage of outline font format is that they can be easily changed by applying a mathematical function to each vector point, scaling them without causing pixellation. Characters in the outline format fonts can be scaled to any size quite easily and they can be changed with smarter results when compared with bitmap fonts, but these fonts require considerably more processing and it may produce undesirable rendering, depending on the font, rendering software, and output size.
On the other hand the outline format fonts have a peculiar problem, that is Bézier curves cannot be displayed by them accurately onto a CRT display and their display can change shape depending on the desired size and position. Some of the modern desktop computer systems include special softwares to perform this job, but these systems have and use considerably more processing power as compared to the bitmap fonts, and there can be minor defects while displaying them, particularly at small font sizes. Despite this, outline fonts are frequently used because people often consider the ability to scale fonts freely.
=== Stroke-based font ===
Generally the outline of the character is defined by the vertices of individual strokes and stroke's shape. The advantage of stroke format fonts over outline fonts comprised of reducing number of vertices needed to define a character and at the same time allowing these vertices to be used to generate a different font that have different weight and character width using different stroke rules and the related size savings.. The stroke-based format allows you to rescale the characters without altering stroke thickness of the base characters.
Have you checked our old english font as of yet?
=== Type 1 and Type 3 Fonts ===
Type 1 and Type 3 fonts were developed by Adobe for professional digital typesetting purposes using post script, here the characters are usually outline fonts expressed with cubic Bezier curves. While the type 1 fonts were usually restricted to a subset of the post script language, the type 3 fonts allowed unobstructed use of the post script language that lead to visible rendering artifacts on low-resolution devices.
=== TrueType Font ===
TrueType font system was initially developed by the Apple Computers with an intention to replace the type 1 fonts. The TrueType characters are depicted with quadratic Bezier curves. These fonts are presently very popular among the masses.
=== OpenType Font ===
OpenType font is a smart font system that was designed by Adobe and Microsoft. OpenType fonts include the outlines in true type or Type 1 format together with a wide range of metadata.
=== METAFONT ===
Metafont uses a different type of character depiction. It is a vector font portrayal system. It draws the characters using strokes produced by moving a polygonal pen approximated by a polygon along a path made from cubic Bézier splines and straight line segments. This method causes no loss of accuracy or resolution.