2fb22d5649
* src/base/ftadvanc.c (FT_Get_Advances): Advance values returned by `FT_Load_Glyph' must be simply multiplied by 1024.
161 lines
5.0 KiB
C
161 lines
5.0 KiB
C
/***************************************************************************/
|
|
/* */
|
|
/* ftadvanc.c */
|
|
/* */
|
|
/* Quick computation of advance widths (body). */
|
|
/* */
|
|
/* Copyright 2008, 2009, 2011 by */
|
|
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
|
|
/* */
|
|
/* This file is part of the FreeType project, and may only be used, */
|
|
/* modified, and distributed under the terms of the FreeType project */
|
|
/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
|
|
/* this file you indicate that you have read the license and */
|
|
/* understand and accept it fully. */
|
|
/* */
|
|
/***************************************************************************/
|
|
|
|
|
|
#include <ft2build.h>
|
|
#include FT_ADVANCES_H
|
|
#include FT_INTERNAL_OBJECTS_H
|
|
|
|
|
|
static FT_Error
|
|
_ft_face_scale_advances( FT_Face face,
|
|
FT_Fixed* advances,
|
|
FT_UInt count,
|
|
FT_Int32 flags )
|
|
{
|
|
FT_Fixed scale;
|
|
FT_UInt nn;
|
|
|
|
|
|
if ( flags & FT_LOAD_NO_SCALE )
|
|
return FT_Err_Ok;
|
|
|
|
if ( face->size == NULL )
|
|
return FT_Err_Invalid_Size_Handle;
|
|
|
|
if ( flags & FT_LOAD_VERTICAL_LAYOUT )
|
|
scale = face->size->metrics.y_scale;
|
|
else
|
|
scale = face->size->metrics.x_scale;
|
|
|
|
/* this must be the same scaling as to get linear{Hori,Vert}Advance */
|
|
/* (see `FT_Load_Glyph' implementation in src/base/ftobjs.c) */
|
|
|
|
for ( nn = 0; nn < count; nn++ )
|
|
advances[nn] = FT_MulDiv( advances[nn], scale, 64 );
|
|
|
|
return FT_Err_Ok;
|
|
}
|
|
|
|
|
|
/* at the moment, we can perform fast advance retrieval only in */
|
|
/* the following cases: */
|
|
/* */
|
|
/* - unscaled load */
|
|
/* - unhinted load */
|
|
/* - light-hinted load */
|
|
|
|
#define LOAD_ADVANCE_FAST_CHECK( flags ) \
|
|
( flags & ( FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING ) || \
|
|
FT_LOAD_TARGET_MODE( flags ) == FT_RENDER_MODE_LIGHT )
|
|
|
|
|
|
/* documentation is in ftadvanc.h */
|
|
|
|
FT_EXPORT_DEF( FT_Error )
|
|
FT_Get_Advance( FT_Face face,
|
|
FT_UInt gindex,
|
|
FT_Int32 flags,
|
|
FT_Fixed *padvance )
|
|
{
|
|
FT_Face_GetAdvancesFunc func;
|
|
|
|
|
|
if ( !face )
|
|
return FT_Err_Invalid_Face_Handle;
|
|
|
|
if ( gindex >= (FT_UInt)face->num_glyphs )
|
|
return FT_Err_Invalid_Glyph_Index;
|
|
|
|
func = face->driver->clazz->get_advances;
|
|
if ( func && LOAD_ADVANCE_FAST_CHECK( flags ) )
|
|
{
|
|
FT_Error error;
|
|
|
|
|
|
error = func( face, gindex, 1, flags, padvance );
|
|
if ( !error )
|
|
return _ft_face_scale_advances( face, padvance, 1, flags );
|
|
|
|
if ( error != FT_ERROR_BASE( FT_Err_Unimplemented_Feature ) )
|
|
return error;
|
|
}
|
|
|
|
return FT_Get_Advances( face, gindex, 1, flags, padvance );
|
|
}
|
|
|
|
|
|
/* documentation is in ftadvanc.h */
|
|
|
|
FT_EXPORT_DEF( FT_Error )
|
|
FT_Get_Advances( FT_Face face,
|
|
FT_UInt start,
|
|
FT_UInt count,
|
|
FT_Int32 flags,
|
|
FT_Fixed *padvances )
|
|
{
|
|
FT_Face_GetAdvancesFunc func;
|
|
FT_UInt num, end, nn;
|
|
FT_Error error = FT_Err_Ok;
|
|
|
|
|
|
if ( !face )
|
|
return FT_Err_Invalid_Face_Handle;
|
|
|
|
num = (FT_UInt)face->num_glyphs;
|
|
end = start + count;
|
|
if ( start >= num || end < start || end > num )
|
|
return FT_Err_Invalid_Glyph_Index;
|
|
|
|
if ( count == 0 )
|
|
return FT_Err_Ok;
|
|
|
|
func = face->driver->clazz->get_advances;
|
|
if ( func && LOAD_ADVANCE_FAST_CHECK( flags ) )
|
|
{
|
|
error = func( face, start, count, flags, padvances );
|
|
if ( !error )
|
|
return _ft_face_scale_advances( face, padvances, count, flags );
|
|
|
|
if ( error != FT_ERROR_BASE( FT_Err_Unimplemented_Feature ) )
|
|
return error;
|
|
}
|
|
|
|
error = FT_Err_Ok;
|
|
|
|
if ( flags & FT_ADVANCE_FLAG_FAST_ONLY )
|
|
return FT_Err_Unimplemented_Feature;
|
|
|
|
flags |= (FT_UInt32)FT_LOAD_ADVANCE_ONLY;
|
|
for ( nn = 0; nn < count; nn++ )
|
|
{
|
|
error = FT_Load_Glyph( face, start + nn, flags );
|
|
if ( error )
|
|
break;
|
|
|
|
/* scale from 26.6 to 16.16 */
|
|
padvances[nn] = ( flags & FT_LOAD_VERTICAL_LAYOUT )
|
|
? face->glyph->advance.y << 10
|
|
: face->glyph->advance.x << 10;
|
|
}
|
|
|
|
return error;
|
|
}
|
|
|
|
|
|
/* END */
|