Add TTF_GetScript to retreive the script to which unicode character b…

…elongs

SDL_ttf.c

@@ -3128,6 +3128,46 @@ int TTF_SetFontScriptName(TTF_Font *font, const char *script)
 #endif
 }
 
+int TTF_GetScript(Uint32 ch, char *script, size_t bufsize)
+{
+#if TTF_USE_HARFBUZZ
+
+    TTF_CHECK_POINTER(script, -1);
+    if (bufsize < 5) {
+        return TTF_SetError("Insufficient script buffer size");
+    }
+
+    hb_buffer_t* hb_buffer = hb_buffer_create();
+
+    if (hb_buffer == NULL) {
+        return TTF_SetError("Cannot create harfbuzz buffer");
+    }
+
+    hb_unicode_funcs_t* hb_unicode_functions = hb_buffer_get_unicode_funcs(hb_buffer);
+
+    if (hb_unicode_functions == NULL) {
+        hb_buffer_destroy(hb_buffer);
+        return TTF_SetError("Cannot get harfbuzz unicode funcs");
+    }
+
+    hb_buffer_clear_contents(hb_buffer);
+    hb_buffer_set_content_type(hb_buffer, HB_BUFFER_CONTENT_TYPE_UNICODE);
+
+    uint8_t const untagged_script[4] = { HB_UNTAG(hb_unicode_script(hb_unicode_functions, ch)) };
+    script[0] = (char)untagged_script[0];
+    script[1] = (char)untagged_script[1];
+    script[2] = (char)untagged_script[2];
+    script[3] = (char)untagged_script[3];
+    script[4] = '\0';
+
+    hb_buffer_destroy(hb_buffer);
+    return 0;
+
+#else
+    return TTF_SetError("Unsupported");
+#endif
+}
+
 static int TTF_Size_Internal(TTF_Font *font,
         const char *text, const str_type_t str_type,
         int *w, int *h, int *xstart, int *ystart,

SDL_ttf.h

@@ -2311,6 +2311,24 @@ extern DECLSPEC int SDLCALL TTF_SetFontDirection(TTF_Font *font, TTF_Direction d
  */
 extern DECLSPEC int SDLCALL TTF_SetFontScriptName(TTF_Font *font, const char *script);
 
+/**
+ * Query the script to which unicode character belongs.
+ *
+ * The supplied script pointer should be able to hold four characters and
+ * the null-terminator.
+ *
+ * If SDL_ttf was not built with HarfBuzz support, this function returns -1.
+ *
+ * \param ch the character to check.
+ * \param script on return, filled in with the the script as a null-terminated
+ *               string of exactly 4 characters
+ * \param bufsize size of the script buffer, must be at least 5 (see above.)
+ * \returns 0 on success, or -1 on error.
+ *
+ * \since This function is available since SDL_ttf 2.24.0.
+ */
+extern DECLSPEC int SDLCALL TTF_GetScript(Uint32 ch, char *script, size_t bufsize);
+
 /* Ends C function definitions when using C++ */
 #ifdef __cplusplus
 }