How to convert a unicode string written in font A to font B?

Question

Assuming all the required fonts are available on client's machine.

1. Probably, you all could see following 'stackoverflow' word written in Indic Language script : 'स्टैकओवरफ्लो' . A quick lookup using Web Developers Tools tells that this word is written using 'Arial, Liberation Sans..' font family. Does that mean Arial font supports Indic language scripts? Is it really Arial font?

2. I want to display all such strings in another unicode font installed on machine. How could I convert it using javascript? My understanding is, since there is no direct 1-1 mapping between these unicode fonts, some kind of conversion might be required.

3. How can I map a unicode font to normal 101 keys US keyboard? So that typing 'stackoverflow' would get converted into 'स्टैकओवरफ्लो' if proper font is selected. It seems using some tools, this is possible. Is this the normal approach? Are there any alternatives?

EDIT1 This and this resource seem to be helpful.

EDIT2 Suppose a particular unicode string could be written in Font A as a combination of ALT+0234, ALT+0244, ALT+0221 on numpad. In Font B, same string would be written via different combination like ALT+0212, ALT+0223, ALT+0242. So how could I do this conversion?

EDIT3 Please see this image for more clarification. See last 2 strings in brackets. Those are the strings I want to convert to and from. Those 2 strings render same Indic string in 2 different fonts.

Answer 1

1. Most modern layout engines have the capability to substitute other fonts if the main font doesn't have a glyph for the current character. This is probably what you're seeing.

2. It's exactly the same text in both fonts; the only issue is that not all fonts may have glyphs for all characters, so they will be unable to display the text properly.

3. You need to use an Input Method Editor in order to enter non-Roman text with a Roman keyboard; see your OS documentation for details.