Unicode: from text and font to display

I’ve always wanted to be able to support all kind of text on my Symbian bible. The problem is this: the Unicode support for Symbian is very limited, and even non existent for some languages. Few weeks ago someone asked me if I can make Symbian bible to support Malayalam bible (using Malayalam script of course). Malayalam writing system was only supported recently by major operating systems (such as Windows XP and OS X Leopard), and Symbian haven’t support it yet (and even if it supports it, the support will only be activated to phones on certain sales area).

I know that there are several Unicode layout library, such as Pango, Qt or ICU. All of them are too big for me to understand and port to Symbian. So my solution was to use the freetype library and harfbuzz font shaping. After using those two libraries on Symbian, I think now I can understand Unicode. Here is my quick guide to understand Unicode, from having a data and a font, to displaying the data with that font.

First thing that you need to understand is: Unicode defines list of characters for many languages of the world.

Some languages doesn’t have the concept of lower or upper case. Some languages have their own numbering system. Every language has their own system of ordering things. If possible: always use the function provided by the library you are using. 

Continue reading “Unicode: from text and font to display”