Does a font file has a seperate table for each character set?

Question

I am trying to understand what is contained in a font file without getting into too much details.

I have created a simple diagram to illustrate my understanding so far, the diagram contains a "glyph table" that encompasses the glyphs available for the font, and each glyph has an index to identify it.

There is also other tables for the character sets supported by the font, there is a Unicode table that will map each Unicode code point to its corresponding glyph, and there is a number of other tables for the supported ANSI code pages.

Now when a program is reading a Unicode text, the program (or Windows that is) will acquire the glyph for each Unicode code point from the Unicode table and displays it. When the program is reading an ANSI text, the program will acquire the glyph for each character code from one of the ANSI tables (depending on the selected ANSI code page in Windows) and displays it.

This is the diagram:

Is my understanding accurate?

Answer 1

OpenType字体可能包含单独的映射表（实际上是cmap表的子表 ），但是在大多数相对较新的情况下，Windows本身（通过Unicode cmap子表）将代码页/字符集划分为Windows。