– Font family, so like for one font family, you might have, multiple later definitions. – This is like a historical name, which refers to the entity, who has created this font. X11 core font naming, is also called X Logical Font Description, which acronym is XLFD. Open Type, which is a vector font, developed by both Microsoft and adobe, and which has an otf extension.True Type, which is a vector font developed by apple, and has a ttf extension.Type1, which is adobe postscript, and which can have the following extensions.This being said X11 core font system, does support the following formats of vector also known as outline fonts: Bitmap fonts are not without advantages, they do not require processing power, so they are faster, and they might scale well down. Outline or vector fonts, are not without limitations, they do require more processing power, they might not scale down in a good manner. an example of outline fonts, are Type 1, true type, and open fonts. ![]() These types of fonts, are called outline or vector fonts. Scaling, in this case, is performed, by using the specified basic drawing primitives, and other algorithms, and when drawing is necessary, the bits are generated. ![]() This being said, the next step in font development was, why not, instead of specifying the bits for each character, just outline, how the character should be drawn, using for example lines, curves, points, and some formulas. Being a series of 1, and 0, scaling did not work well, but it can nevertheless be performed, using a given algorithm, like why not proportion, or nearest neighbor, or anything else. Well all the previous fonts, were bitmap fonts, so they are just a series of 1 and 0. So these were the fonts, which were based on BDF, what happened next you might ask ? Hence the next idea, why not have a platform independent, compressed version of BDF ? This led to the birth of PCF, which stands for the portable compiled format, and which can be used on any platform, or architecture, even if compiled on a different one. So in other words, it was platform dependent. The SNF format, was used in in X11R4, but its main problem was, is that it was not portable, so if compiled for an architecture, it cannot be used for another. So this led, to the birth of SNF, which stands for Sever normal format. So the next idea was, why not provide a compressed version of this format. The BDF format, needed to be compiled, for different architectures, and it was not compressed. This was simply an ASCII file, which defined the font, by using keys and values, as in:įONT -adobe-courier-bold-o-normal-10-100-75-75-m-60-iso10646-1 BDF, stands for bitmap distribution format. To start with, adobe came up with the BDF format. This being said, a natural question to ask, is, what are the font formats, supported by the server? So when designing, the idea was to minimize network bandwidth or transfer, as such some control was relinquished, to the entity responsible for handling the API calls, the server, hence the server was responsible for having the fonts, and creating bitmaps from characters. So the API calls, or the function calls, which are done by your program, called the client, are going to be done over a medium, the network. So, why the use of the term server and client, you might ask? Because when X11 was designed, it had in mind that communication will be done over a network. The server is responsible for converting characters, into bitmaps, using the fonts that it has installed. In X11 core font system, the server is responsible for having the fonts, so the fonts are stored, or installed on the server. ![]() X11 core font system What is X11 core font system?
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