HRESULT opentype_get_font_table(IDWriteFontFileStream *stream, DWRITE_FONT_FACE_TYPE type, UINT32 font_index, UINT32 tag,
const void **table_data, void **table_context, UINT32 *table_size, BOOL *found)
{
HRESULT hr;
TTC_SFNT_V1 *font_header = NULL;
void *sfnt_context;
TT_TableRecord *table_record = NULL;
void *table_record_context;
int table_count, table_offset = 0;
int i;
if (found) *found = FALSE;
if (table_size) *table_size = 0;
if (type == DWRITE_FONT_FACE_TYPE_TRUETYPE_COLLECTION) {
const TTC_Header_V1 *ttc_header;
void * ttc_context;
hr = IDWriteFontFileStream_ReadFileFragment(stream, (const void**)&ttc_header, 0, sizeof(*ttc_header), &ttc_context);
if (SUCCEEDED(hr)) {
table_offset = GET_BE_DWORD(ttc_header->OffsetTable[0]);
if (font_index >= GET_BE_DWORD(ttc_header->numFonts))
hr = E_INVALIDARG;
else
hr = IDWriteFontFileStream_ReadFileFragment(stream, (const void**)&font_header, table_offset, sizeof(*font_header), &sfnt_context);
IDWriteFontFileStream_ReleaseFileFragment(stream, ttc_context);
}
}
else
hr = IDWriteFontFileStream_ReadFileFragment(stream, (const void**)&font_header, 0, sizeof(*font_header), &sfnt_context);
if (FAILED(hr))
return hr;
table_count = GET_BE_WORD(font_header->numTables);
table_offset += sizeof(*font_header);
for (i = 0; i < table_count; i++)
{
hr = IDWriteFontFileStream_ReadFileFragment(stream, (const void**)&table_record, table_offset, sizeof(*table_record), &table_record_context);
if (FAILED(hr))
break;
if (DWRITE_MAKE_OPENTYPE_TAG(table_record->tag[0], table_record->tag[1], table_record->tag[2], table_record->tag[3]) == tag)
break;
IDWriteFontFileStream_ReleaseFileFragment(stream, table_record_context);
table_offset += sizeof(*table_record);
}
IDWriteFontFileStream_ReleaseFileFragment(stream, sfnt_context);
if (SUCCEEDED(hr) && i < table_count)
{
int offset = GET_BE_DWORD(table_record->offset);
int length = GET_BE_DWORD(table_record->length);
IDWriteFontFileStream_ReleaseFileFragment(stream, table_record_context);
if (found) *found = TRUE;
if (table_size) *table_size = length;
hr = IDWriteFontFileStream_ReadFileFragment(stream, table_data, offset, length, table_context);
}
return hr;
}
void opentype_get_font_properties(IDWriteFontFileStream *stream, DWRITE_FONT_FACE_TYPE type, UINT32 index,
struct dwrite_font_props *props)
{
void *os2_context, *head_context;
const TT_OS2_V2 *tt_os2;
const TT_HEAD *tt_head;
opentype_get_font_table(stream, type, index, MS_OS2_TAG, (const void**)&tt_os2, &os2_context, NULL, NULL);
opentype_get_font_table(stream, type, index, MS_HEAD_TAG, (const void**)&tt_head, &head_context, NULL, NULL);
/* default stretch, weight and style to normal */
props->stretch = DWRITE_FONT_STRETCH_NORMAL;
props->weight = DWRITE_FONT_WEIGHT_NORMAL;
props->style = DWRITE_FONT_STYLE_NORMAL;
memset(&props->panose, 0, sizeof(props->panose));
/* DWRITE_FONT_STRETCH enumeration values directly match font data values */
if (tt_os2) {
if (GET_BE_WORD(tt_os2->usWidthClass) <= DWRITE_FONT_STRETCH_ULTRA_EXPANDED)
props->stretch = GET_BE_WORD(tt_os2->usWidthClass);
props->weight = GET_BE_WORD(tt_os2->usWeightClass);
memcpy(&props->panose, &tt_os2->panose, sizeof(props->panose));
TRACE("stretch=%d, weight=%d\n", props->stretch, props->weight);
}
if (tt_head) {
USHORT macStyle = GET_BE_WORD(tt_head->macStyle);
if (macStyle & 0x0002)
props->style = DWRITE_FONT_STYLE_ITALIC;
}
if (tt_os2)
IDWriteFontFileStream_ReleaseFileFragment(stream, os2_context);
if (tt_head)
IDWriteFontFileStream_ReleaseFileFragment(stream, head_context);
}
HRESULT opentype_analyze_font(IDWriteFontFileStream *stream, UINT32* font_count, DWRITE_FONT_FILE_TYPE *file_type, DWRITE_FONT_FACE_TYPE *face_type, BOOL *supported)
{
/* TODO: Do font validation */
DWRITE_FONT_FACE_TYPE face;
const void *font_data;
const char* tag;
void *context;
HRESULT hr;
hr = IDWriteFontFileStream_ReadFileFragment(stream, &font_data, 0, sizeof(TTC_Header_V1), &context);
if (FAILED(hr))
return hr;
tag = font_data;
*file_type = DWRITE_FONT_FILE_TYPE_UNKNOWN;
face = DWRITE_FONT_FACE_TYPE_UNKNOWN;
*font_count = 0;
if (DWRITE_MAKE_OPENTYPE_TAG(tag[0], tag[1], tag[2], tag[3]) == MS_TTCF_TAG)
{
const TTC_Header_V1 *header = font_data;
*font_count = GET_BE_DWORD(header->numFonts);
*file_type = DWRITE_FONT_FILE_TYPE_TRUETYPE_COLLECTION;
face = DWRITE_FONT_FACE_TYPE_TRUETYPE_COLLECTION;
}
else if (GET_BE_DWORD(*(DWORD*)font_data) == 0x10000)
{
*font_count = 1;
*file_type = DWRITE_FONT_FILE_TYPE_TRUETYPE;
face = DWRITE_FONT_FACE_TYPE_TRUETYPE;
}
else if (DWRITE_MAKE_OPENTYPE_TAG(tag[0], tag[1], tag[2], tag[3]) == MS_OTTO_TAG)
{
*file_type = DWRITE_FONT_FILE_TYPE_CFF;
face = DWRITE_FONT_FACE_TYPE_CFF;
}
if (face_type)
*face_type = face;
*supported = is_face_type_supported(face);
IDWriteFontFileStream_ReleaseFileFragment(stream, context);
return S_OK;
}
void opentype_get_font_metrics(IDWriteFontFileStream *stream, DWRITE_FONT_FACE_TYPE face_type, UINT32 face_index,
DWRITE_FONT_METRICS1 *metrics, DWRITE_CARET_METRICS *caret)
{
void *os2_context, *head_context, *post_context, *hhea_context;
const TT_OS2_V2 *tt_os2;
const TT_HEAD *tt_head;
const TT_POST *tt_post;
const TT_HHEA *tt_hhea;
memset(metrics, 0, sizeof(*metrics));
opentype_get_font_table(stream, face_type, face_index, MS_OS2_TAG, (const void**)&tt_os2, &os2_context, NULL, NULL);
opentype_get_font_table(stream, face_type, face_index, MS_HEAD_TAG, (const void**)&tt_head, &head_context, NULL, NULL);
opentype_get_font_table(stream, face_type, face_index, MS_POST_TAG, (const void**)&tt_post, &post_context, NULL, NULL);
opentype_get_font_table(stream, face_type, face_index, MS_HHEA_TAG, (const void**)&tt_hhea, &hhea_context, NULL, NULL);
if (tt_head) {
metrics->designUnitsPerEm = GET_BE_WORD(tt_head->unitsPerEm);
metrics->glyphBoxLeft = GET_BE_WORD(tt_head->xMin);
metrics->glyphBoxTop = GET_BE_WORD(tt_head->yMax);
metrics->glyphBoxRight = GET_BE_WORD(tt_head->xMax);
metrics->glyphBoxBottom = GET_BE_WORD(tt_head->yMin);
}
if (caret) {
if (tt_hhea) {
caret->slopeRise = GET_BE_WORD(tt_hhea->caretSlopeRise);
caret->slopeRun = GET_BE_WORD(tt_hhea->caretSlopeRun);
caret->offset = GET_BE_WORD(tt_hhea->caretOffset);
}
else {
caret->slopeRise = 0;
caret->slopeRun = 0;
caret->offset = 0;
}
}
if (tt_os2) {
USHORT version = GET_BE_WORD(tt_os2->version);
metrics->ascent = GET_BE_WORD(tt_os2->usWinAscent);
metrics->descent = GET_BE_WORD(tt_os2->usWinDescent);
/* line gap is estimated using two sets of ascender/descender values and 'hhea' line gap */
if (tt_hhea) {
SHORT descender = (SHORT)GET_BE_WORD(tt_hhea->descender);
INT32 linegap;
linegap = GET_BE_WORD(tt_hhea->ascender) + abs(descender) + GET_BE_WORD(tt_hhea->linegap) -
metrics->ascent - metrics->descent;
metrics->lineGap = linegap > 0 ? linegap : 0;
}
metrics->strikethroughPosition = GET_BE_WORD(tt_os2->yStrikeoutPosition);
metrics->strikethroughThickness = GET_BE_WORD(tt_os2->yStrikeoutSize);
metrics->subscriptPositionX = GET_BE_WORD(tt_os2->ySubscriptXOffset);
/* Y offset is stored as positive offset below baseline */
metrics->subscriptPositionY = -GET_BE_WORD(tt_os2->ySubscriptYOffset);
metrics->subscriptSizeX = GET_BE_WORD(tt_os2->ySubscriptXSize);
metrics->subscriptSizeY = GET_BE_WORD(tt_os2->ySubscriptYSize);
metrics->superscriptPositionX = GET_BE_WORD(tt_os2->ySuperscriptXOffset);
metrics->superscriptPositionY = GET_BE_WORD(tt_os2->ySuperscriptYOffset);
metrics->superscriptSizeX = GET_BE_WORD(tt_os2->ySuperscriptXSize);
metrics->superscriptSizeY = GET_BE_WORD(tt_os2->ySuperscriptYSize);
/* version 2 fields */
if (version >= 2) {
metrics->capHeight = GET_BE_WORD(tt_os2->sCapHeight);
metrics->xHeight = GET_BE_WORD(tt_os2->sxHeight);
}
/* version 4 fields */
if (version >= 4) {
if (GET_BE_WORD(tt_os2->fsSelection) & OS2_FSSELECTION_USE_TYPO_METRICS) {
SHORT descent = GET_BE_WORD(tt_os2->sTypoDescender);
metrics->ascent = GET_BE_WORD(tt_os2->sTypoAscender);
metrics->descent = descent < 0 ? -descent : 0;
metrics->lineGap = GET_BE_WORD(tt_os2->sTypoLineGap);
metrics->hasTypographicMetrics = TRUE;
}
}
}
if (tt_post) {
metrics->underlinePosition = GET_BE_WORD(tt_post->underlinePosition);
metrics->underlineThickness = GET_BE_WORD(tt_post->underlineThickness);
}
/* estimate missing metrics */
if (metrics->xHeight == 0)
metrics->xHeight = metrics->designUnitsPerEm / 2;
if (metrics->capHeight == 0)
metrics->capHeight = metrics->designUnitsPerEm * 7 / 10;
if (tt_os2)
IDWriteFontFileStream_ReleaseFileFragment(stream, os2_context);
if (tt_head)
IDWriteFontFileStream_ReleaseFileFragment(stream, head_context);
if (tt_post)
IDWriteFontFileStream_ReleaseFileFragment(stream, post_context);
if (tt_hhea)
IDWriteFontFileStream_ReleaseFileFragment(stream, hhea_context);
}