VVVVVV/desktop_version/src/FontBidi.h

#ifndef FONTBIDI_H
#define FONTBIDI_H

namespace font
{

void bidi_init(void);
void bidi_destroy(void);
bool bidi_should_transform(const char* text);
const char* bidi_transform(const char* text);

} // namespace font

#endif // FONTBIDI_H
Implement bidi reordering at display time I'm now using SheenBidi to reorder RTL and bidirectional text properly at text rendering time! For Arabic this is still missing reshaping, but everything's looking really promising now! The code changes are really non-invasive. The changes to Font.cpp are absolutely minimal: 1305+ if (bidi_should_transform(text)) 1306+ { 1307+ text = bidi_transform(text); 1308+ } There's now a FontBidi.cpp, which implements these two functions, notably bidi_transform(), which takes a UTF-8 encoded string and returns another UTF-8 encoded string that has bidi reorderings and reshapings applied. In that function, SheenBidi gives us information about where in the input string runs start and end, and on a basic level, all we need to do there is to concatenate the parts together in the order that we're given them, and to reverse the RTL runs (recognizable by odd levels). As this is a proof-of-concept, bidi_should_transform() still always returns true, applying the bidi algorithm to all languages and all strings. I'm thinking of enabling bidi only when the language/font metadata enables RTL (which could be for the interface or for a custom level), or outside of that, at least when RTL characters are detected (such as Arabic or Hebrew Unicode blocks). 2024-01-02 03:57:26 +01:00			`#ifndef FONTBIDI_H`
			`#define FONTBIDI_H`

			`namespace font`
			`{`

Add Arabic reshaping lookup table This adds the lookup table and an accompanying hashmap that will be used for reshaping Arabic - it's not yet used though. 2024-01-02 05:01:39 +01:00			`void bidi_init(void);`
			`void bidi_destroy(void);`
Implement bidi reordering at display time I'm now using SheenBidi to reorder RTL and bidirectional text properly at text rendering time! For Arabic this is still missing reshaping, but everything's looking really promising now! The code changes are really non-invasive. The changes to Font.cpp are absolutely minimal: 1305+ if (bidi_should_transform(text)) 1306+ { 1307+ text = bidi_transform(text); 1308+ } There's now a FontBidi.cpp, which implements these two functions, notably bidi_transform(), which takes a UTF-8 encoded string and returns another UTF-8 encoded string that has bidi reorderings and reshapings applied. In that function, SheenBidi gives us information about where in the input string runs start and end, and on a basic level, all we need to do there is to concatenate the parts together in the order that we're given them, and to reverse the RTL runs (recognizable by odd levels). As this is a proof-of-concept, bidi_should_transform() still always returns true, applying the bidi algorithm to all languages and all strings. I'm thinking of enabling bidi only when the language/font metadata enables RTL (which could be for the interface or for a custom level), or outside of that, at least when RTL characters are detected (such as Arabic or Hebrew Unicode blocks). 2024-01-02 03:57:26 +01:00			`bool bidi_should_transform(const char* text);`
			`const char* bidi_transform(const char* text);`

			`} // namespace font`

			`#endif // FONTBIDI_H`