X11TK: Add Arabic/Hebrew/Farsi support by increasing font size slightly and using FriBidi. (#14134)

2025-10-07 02:16:26 +00:00 · 2025-10-04 05:08:24 +03:00
parent 49d51a0d3c
commit c2429e85ec
9 changed files with 503 additions and 30 deletions
--- a/src/core/unix/SDL_fribidi.c
+++ b/src/core/unix/SDL_fribidi.c
@@ -0,0 +1,160 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifdef HAVE_FRIBIDI_H
+
+#include "SDL_internal.h"
+#include "SDL_fribidi.h"
+#include <fribidi.h>
+
+SDL_FriBidi *SDL_FriBidi_Create(void) {
+	SDL_FriBidi *fribidi;
+
+	fribidi = (SDL_FriBidi *)SDL_malloc(sizeof(SDL_FriBidi)); 
+	if (!fribidi) {
+		return NULL;
+	}
+
+#ifdef SDL_FRIBIDI_DYNAMIC	
+	#define SDL_FRIBIDI_LOAD_SYM(x, n, t) x = ((t)SDL_LoadFunction(fribidi->lib, n)); if (!x) { SDL_UnloadObject(fribidi->lib); SDL_free(fribidi); return NULL; }
+
+	fribidi->lib = SDL_LoadObject(SDL_FRIBIDI_DYNAMIC);
+	if (!fribidi->lib) {
+		SDL_free(fribidi);
+		return NULL;	
+	}
+		
+	SDL_FRIBIDI_LOAD_SYM(fribidi->unicode_to_charset, "fribidi_unicode_to_charset", SDL_FriBidiUnicodeToCharset);
+	SDL_FRIBIDI_LOAD_SYM(fribidi->charset_to_unicode, "fribidi_charset_to_unicode", SDL_FriBidiCharsetToUnicode);
+	SDL_FRIBIDI_LOAD_SYM(fribidi->get_bidi_types, "fribidi_get_bidi_types", SDL_FriBidiGetBidiTypes);
+	SDL_FRIBIDI_LOAD_SYM(fribidi->get_par_direction, "fribidi_get_par_direction", SDL_FriBidiGetParDirection);
+	SDL_FRIBIDI_LOAD_SYM(fribidi->get_par_embedding_levels, "fribidi_get_par_embedding_levels", SDL_FriBidiGetParEmbeddingLevels);
+	SDL_FRIBIDI_LOAD_SYM(fribidi->get_joining_types, "fribidi_get_joining_types", SDL_FriBidiGetJoiningTypes);
+	SDL_FRIBIDI_LOAD_SYM(fribidi->join_arabic, "fribidi_join_arabic", SDL_FriBidiJoinArabic);
+	SDL_FRIBIDI_LOAD_SYM(fribidi->shape, "fribidi_shape", SDL_FriBidiShape);
+	SDL_FRIBIDI_LOAD_SYM(fribidi->reorder_line, "fribidi_reorder_line", SDL_FriBidiReorderLine);
+#else 
+	fribidi->unicode_to_charset = fribidi_unicode_to_charset;
+	fribidi->charset_to_unicode = fribidi_charset_to_unicode;
+	fribidi->get_bidi_types = fribidi_get_bidi_types;
+	fribidi->get_par_direction = fribidi_get_par_direction;
+	fribidi->get_par_embedding_levels = fribidi_get_par_embedding_levels;
+	fribidi->get_joining_types = fribidi_get_joining_types;
+	fribidi->join_arabic = fribidi_join_arabic;
+	fribidi->shape = fribidi_shape;
+	fribidi->reorder_line = fribidi_reorder_line;
+#endif
+
+	return fribidi;
+}
+
+char *SDL_FriBidi_Process(SDL_FriBidi *fribidi, char *utf8, ssize_t utf8_len, bool shaping, FriBidiParType *out_par_type) {
+    FriBidiCharType *types;
+    FriBidiLevel *levels;
+    FriBidiArabicProp *props;
+	FriBidiChar *str;
+	char *result;
+    FriBidiStrIndex len;
+	FriBidiLevel max_level;
+    FriBidiLevel start;
+    FriBidiLevel end;
+    FriBidiParType direction;
+    FriBidiParType str_direction;
+    unsigned int i;
+    unsigned int c;
+
+    if (!fribidi || !utf8) {
+        return NULL;
+    }
+
+	/* Convert to UTF32 */
+	if (utf8_len < 0) {
+		utf8_len = SDL_strlen(utf8);
+	}
+    str = SDL_calloc(SDL_utf8strnlen(utf8, utf8_len), sizeof(FriBidiChar));
+    len = fribidi->charset_to_unicode(FRIBIDI_CHAR_SET_UTF8, utf8, utf8_len, str);
+    
+    /* Setup various BIDI structures */
+    direction = FRIBIDI_PAR_LTR;
+    types = NULL;
+    levels = NULL;
+    props = SDL_calloc(len + 1, sizeof(FriBidiArabicProp));
+    levels = SDL_calloc(len + 1, sizeof(FriBidiLevel));
+    types = SDL_calloc(len + 1, sizeof(FriBidiCharType));
+
+	/* Shape */
+    fribidi->get_bidi_types(str, len, types);
+	str_direction = fribidi->get_par_direction(types, len);
+	max_level = fribidi->get_par_embedding_levels(types, len, &direction, levels);
+	if (shaping) {
+		fribidi->get_joining_types(str, len, props);
+		fribidi->join_arabic(types, len, levels, props);
+		fribidi->shape(FRIBIDI_FLAGS_DEFAULT | FRIBIDI_FLAGS_ARABIC, levels, len, props, str);
+	}
+	
+	/* BIDI */
+    for (end = 0, start = 0; end < len; end++) {
+        if (str[end] == '\n' || str[end] == '\r' || str[end] == '\f' || str[end] == '\v' || end == len - 1) {
+            max_level = fribidi->reorder_line(FRIBIDI_FLAGS_DEFAULT | FRIBIDI_FLAGS_ARABIC, types, end - start + 1, start, direction, levels, str, NULL);
+            start = end + 1;
+        }
+    }
+	
+	/* Silence warning */
+	(void)max_level;
+	
+	/* Remove fillers */
+    for (i = 0, c = 0; i < len; i++) {
+        if (str[i] != FRIBIDI_CHAR_FILL) {
+            str[c++] = str[i];
+        }
+    }
+    len = c;
+
+	/* Convert back to UTF8 */
+    result = SDL_malloc(len * 4 + 1);
+    fribidi->unicode_to_charset(FRIBIDI_CHAR_SET_UTF8, str, len, result);
+
+	/* Cleanup */
+    SDL_free(levels);
+    SDL_free(props);
+    SDL_free(types);
+	
+	/* Return */
+	if (out_par_type) {
+		*out_par_type = str_direction;		
+	}
+	return result;
+}
+
+void SDL_FriBidi_Destroy(SDL_FriBidi *fribidi) {
+	if (!fribidi) {
+		return;
+	}
+	
+#ifdef SDL_FRIBIDI_DYNAMIC	
+	SDL_UnloadObject(fribidi->lib); 
+#endif
+
+	SDL_free(fribidi);
+}
+
+#endif