diff options
Diffstat (limited to 'libass/ass_font.c')
| -rw-r--r-- | libass/ass_font.c | 173 |
1 files changed, 167 insertions, 6 deletions
diff --git a/libass/ass_font.c b/libass/ass_font.c index 79ab22b..3f44a1f 100644 --- a/libass/ass_font.c +++ b/libass/ass_font.c @@ -26,6 +26,7 @@ #include FT_GLYPH_H #include FT_TRUETYPE_TABLES_H #include FT_OUTLINE_H +#include FT_TRUETYPE_IDS_H #include <limits.h> #include "ass.h" @@ -36,6 +37,156 @@ #include "ass_shaper.h" /** + * Get the mbcs codepoint from the output bytes of iconv/WideCharToMultiByte, + * by treating the bytes as a prefix-zero-byte-omitted big-endian integer. + */ +static inline uint32_t pack_mbcs_bytes(const char *bytes, size_t length) +{ + uint32_t ret = 0; + for (size_t i = 0; i < length; ++i) { + ret <<= 8; + ret |= (uint8_t) bytes[i]; + } + return ret; +} + +/** + * Convert a UCS-4 code unit to a packed uint32_t in given multibyte encoding. + * + * We don't exclude Cygwin for Windows since we use WideCharToMultiByte only, + * this shall not violate any Cygwin restrictions on Windows APIs. + */ +#if defined(_WIN32) + +#define WIN32_LEAN_AND_MEAN +#include <windows.h> + +static uint32_t convert_unicode_to_mb(FT_Encoding encoding, uint32_t codepoint) +{ + // map freetype encoding to windows codepage + UINT codepage; + switch (encoding) { + case FT_ENCODING_MS_SJIS: + codepage = 932; + break; + case FT_ENCODING_MS_GB2312: + codepage = 936; + break; + case FT_ENCODING_MS_BIG5: + codepage = 950; + break; + case FT_ENCODING_MS_WANSUNG: + codepage = 949; + break; + case FT_ENCODING_MS_JOHAB: + codepage = 1361; + break; + default: + return codepoint; + } + + WCHAR input_buffer[2]; + size_t inbuf_size; + + // encode surrogate pair, assuming codepoint > 0 && codepoint <= 10FFFF + if (codepoint >= 0x10000) { + // surrogate pair required + inbuf_size = 2; + input_buffer[0] = 0xD7C0 + (codepoint >> 10); + input_buffer[1] = 0xDC00 + (codepoint & 0x3FF); + } else { + inbuf_size = 1; + input_buffer[0] = codepoint; + } + + // do convert + char output_buffer[2]; + BOOL conversion_fail; + int output_length = WideCharToMultiByte(codepage, WC_NO_BEST_FIT_CHARS, input_buffer, inbuf_size, + output_buffer, sizeof(output_buffer), NULL, &conversion_fail); + if (output_length == 0 || conversion_fail) + return codepoint; + + return pack_mbcs_bytes(output_buffer, output_length); +} +#elif defined(CONFIG_ICONV) + +#include <iconv.h> + +static uint32_t convert_unicode_to_mb(FT_Encoding encoding, uint32_t codepoint) +{ + typedef struct { const char *names[5]; } EncodingList; + + EncodingList encoding_list; + + // map freetype encoding to iconv encoding + switch (encoding) { + case FT_ENCODING_MS_SJIS: + encoding_list = (EncodingList) {{"CP932", "SHIFT_JIS", NULL}}; + break; + case FT_ENCODING_MS_GB2312: + encoding_list = (EncodingList) {{"CP936", "GBK", "GB18030", "GB2312", NULL}}; + break; + case FT_ENCODING_MS_BIG5: + encoding_list = (EncodingList) {{"CP950", "BIG5", NULL}}; + break; + case FT_ENCODING_MS_WANSUNG: + encoding_list = (EncodingList) {{"CP949", "EUC-KR", NULL}}; + break; + case FT_ENCODING_MS_JOHAB: + encoding_list = (EncodingList) {{"CP1361", "JOHAB", NULL}}; + break; + default: + return codepoint; + } + + // open iconv context + const char **encoding_str = encoding_list.names; + iconv_t cd = (iconv_t) -1; + while (*encoding_str) { + cd = iconv_open(*encoding_str, "UTF-32LE"); + if (cd != (iconv_t) -1) break; + ++encoding_str; + } + if (cd == (iconv_t) -1) + return codepoint; + + char input_buffer[4]; + char output_buffer[2]; // MS-flavour encodings only need 2 bytes + uint32_t result = codepoint; + + // convert input codepoint to little endian uint32_t bytearray + for (int i = 0; i < 4; ++i) { + input_buffer[i] = result & 0xFF; + result >>= 8; + } + result = codepoint; + + // do actual convert, only reversible converts are valid, since we are converting unicode to something else + size_t inbuf_size = sizeof(input_buffer); + size_t outbuf_size = sizeof(output_buffer); + char *inbuf = input_buffer; + char *outbuf = output_buffer; + if (iconv(cd, &inbuf, &inbuf_size, &outbuf, &outbuf_size)) + goto clean; + + // now we have multibyte string in output_buffer + // assemble those bytes into uint32_t + size_t output_length = sizeof(output_buffer) - outbuf_size; + result = pack_mbcs_bytes(output_buffer, output_length); + +clean: + iconv_close(cd); + return result; +} +#else +static uint32_t convert_unicode_to_mb(FT_Encoding encoding, uint32_t codepoint) { + // just a stub + return codepoint; +} +#endif + +/** * Select a good charmap, prefer Microsoft Unicode charmaps. * Otherwise, let FreeType decide. */ @@ -79,7 +230,7 @@ void charmap_magic(ASS_Library *library, FT_Face face) /** * Adjust char index if the charmap is weird - * (currently just MS Symbol) + * (currently all non-Unicode Microsoft cmap) */ uint32_t ass_font_index_magic(FT_Face face, uint32_t symbol) @@ -87,12 +238,22 @@ uint32_t ass_font_index_magic(FT_Face face, uint32_t symbol) if (!face->charmap) return symbol; - switch (face->charmap->encoding) { - case FT_ENCODING_MS_SYMBOL: - return 0xF000 | symbol; - default: - return symbol; + if (face->charmap->platform_id == TT_PLATFORM_MICROSOFT) { + switch (face->charmap->encoding) { + case FT_ENCODING_MS_SYMBOL: + return 0xF000 | symbol; + case FT_ENCODING_MS_SJIS: + case FT_ENCODING_MS_GB2312: + case FT_ENCODING_MS_BIG5: + case FT_ENCODING_MS_WANSUNG: + case FT_ENCODING_MS_JOHAB: + return convert_unicode_to_mb(face->charmap->encoding, symbol); + default: + return symbol; + } } + + return symbol; } static void set_font_metrics(FT_Face face) |