Added the incremental loading system for the TrueType driver.

Tested using my own unit test code.
This commit is contained in:
Graham Asher 2002-07-18 15:59:23 +00:00
parent d53cf1df31
commit 13217f2509
2 changed files with 110 additions and 24 deletions

View File

@ -750,15 +750,18 @@
TT_Face face = (TT_Face)loader->face;
FT_ULong offset;
FT_Int contours_count;
FT_UInt idx, num_points, count;
FT_UInt num_points, count;
FT_Fixed x_scale, y_scale;
FT_GlyphLoader gloader = loader->gloader;
FT_Bool opened_frame = 0;
#ifdef FT_CONFIG_OPTION_INCREMENTAL
struct FT_StreamRec_ inc_stream;
#endif
/* check glyph index */
idx = glyph_index;
if ( idx >= (FT_UInt)face->root.num_glyphs )
glyph_index;
if ( glyph_index >= (FT_UInt)face->root.num_glyphs )
{
error = TT_Err_Invalid_Glyph_Index;
goto Exit;
@ -777,16 +780,40 @@
/* get horizontal metrics */
{
FT_Short left_bearing;
FT_UShort advance_width;
FT_Short left_bearing = 0;
FT_UShort advance_width = 0;
#ifdef FT_CONFIG_OPTION_INCREMENTAL
FT_Bool metrics_found = FALSE;
Get_HMetrics( face, idx,
/* If this is an incrementally loaded font see if there are overriding metrics for this glyph. */
if (face->root.incremental_interface && face->root.incremental_interface->funcs->get_glyph_metrics)
{
FT_Basic_Glyph_Metrics m;
error = face->root.incremental_interface->funcs->get_glyph_metrics(face->root.incremental_interface->object,
glyph_index,FALSE,&m,&metrics_found);
if (error)
goto Exit;
left_bearing = (FT_Short)m.bearing_x;
advance_width = (FT_UShort)m.advance;
}
if (!metrics_found)
Get_HMetrics( face, glyph_index,
(FT_Bool)!( loader->load_flags &
FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH ),
&left_bearing,
&advance_width );
#else
Get_HMetrics( face, glyph_index,
(FT_Bool)!( loader->load_flags &
FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH ),
&left_bearing,
&advance_width );
#endif
loader->left_bearing = left_bearing;
loader->advance = advance_width;
@ -797,11 +824,37 @@
}
}
offset = face->glyph_locations[idx];
count = 0;
#ifdef FT_CONFIG_OPTION_INCREMENTAL
/*
Set 'offset' to the start of the glyph program relative to the start of the 'glyf' table,
and 'count' to the length of the glyph program in bytes.
if ( idx < (FT_UInt)face->num_locations - 1 )
count = face->glyph_locations[idx + 1] - offset;
If we are loading glyph data via the incremental interface, set the loader stream to a memory
stream reading the data returned by the interface.
*/
if (face->root.incremental_interface)
{
FT_Data data;
error = face->root.incremental_interface->funcs->get_glyph_data(face->root.incremental_interface->object,
glyph_index,&data);
if (error)
goto Exit;
offset = 0;
count = data.length;
memset(&inc_stream,0,sizeof(inc_stream));
FT_Stream_OpenMemory(&inc_stream,data.pointer,data.length);
loader->stream = &inc_stream;
}
else
#endif
{
offset = face->glyph_locations[glyph_index];
count = 0;
if ( glyph_index < (FT_UInt)face->num_locations - 1 )
count = face->glyph_locations[glyph_index + 1] - offset;
}
if ( count == 0 )
{
@ -1200,7 +1253,7 @@
}
static void
static FT_Error
compute_glyph_metrics( TT_Loader loader,
FT_UInt glyph_index )
{
@ -1279,10 +1332,25 @@
FT_Pos left; /* scaled vertical left side bearing */
FT_Pos top; /* scaled vertical top side bearing */
FT_Pos advance; /* scaled vertical advance height */
FT_Bool metrics_found = FALSE;
#ifdef FT_CONFIG_OPTION_INCREMENTAL
/* If this is an incrementally loaded font see if there are overriding metrics for this glyph. */
if (face->root.incremental_interface && face->root.incremental_interface->funcs->get_glyph_metrics)
{
FT_Basic_Glyph_Metrics m;
FT_Error error =
face->root.incremental_interface->funcs->get_glyph_metrics(face->root.incremental_interface->object,
glyph_index,TRUE,&m,&metrics_found);
if (error)
return error;
top_bearing = (FT_Short)m.bearing_y;
advance_height = (FT_UShort)m.advance;
}
#endif
/* Get the unscaled `tsb' and `ah' */
if ( face->vertical_info &&
/* Get the unscaled top bearing and advance height. */
if ( !metrics_found && face->vertical_info &&
face->vertical.number_Of_VMetrics > 0 )
{
/* Don't assume that both the vertical header and vertical */
@ -1377,6 +1445,8 @@
/* set glyph dimensions */
glyph->metrics.width = bbox.xMax - bbox.xMin;
glyph->metrics.height = bbox.yMax - bbox.yMin;
return 0;
}
@ -1498,13 +1568,18 @@
/* seek to the beginning of the glyph table. For Type 42 fonts */
/* the table might be accessed from a Postscript stream or something */
/* else... */
error = face->goto_table( face, TTAG_glyf, stream, 0 );
if ( error )
{
FT_ERROR(( "TT_Load_Glyph: could not access glyph table\n" ));
goto Exit;
}
#ifdef FT_CONFIG_OPTION_INCREMENTAL
/* Don't look for the glyph table if this is an incremental font. */
if (!face->root.incremental_interface)
#endif
{
error = face->goto_table( face, TTAG_glyf, stream, 0 );
if ( error )
{
FT_ERROR(( "TT_Load_Glyph: could not access glyph table\n" ));
goto Exit;
}
}
FT_MEM_SET( &loader, 0, sizeof ( loader ) );
@ -1552,7 +1627,12 @@
loader.glyph = (FT_GlyphSlot)glyph;
loader.stream = stream;
loader.glyf_offset = FT_STREAM_POS();
#ifdef FT_CONFIG_OPTION_INCREMENTAL
if (face->root.incremental_interface)
loader.glyf_offset = 0;
else
#endif
loader.glyf_offset = FT_STREAM_POS();
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER

View File

@ -197,9 +197,15 @@
goto Exit;
if ( face->root.face_flags & FT_FACE_FLAG_SCALABLE )
error = TT_Load_Locations( face, stream ) ||
TT_Load_CVT ( face, stream ) ||
TT_Load_Programs ( face, stream );
{
#ifdef FT_CONFIG_OPTION_INCREMENTAL
if ( !face->root.incremental_interface )
error = TT_Load_Locations( face, stream );
if ( !error )
#endif
error = TT_Load_CVT ( face, stream ) ||
TT_Load_Programs ( face, stream );
}
/* initialize standard glyph loading routines */
TT_Init_Glyph_Loading( face );