1 /***************************************************************************/
5 /* Quick computation of advance widths (body). */
7 /* Copyright 2008, 2009 by */
8 /* David Turner, Robert Wilhelm, and Werner Lemberg. */
10 /* This file is part of the FreeType project, and may only be used, */
11 /* modified, and distributed under the terms of the FreeType project */
12 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */
13 /* this file you indicate that you have read the license and */
14 /* understand and accept it fully. */
16 /***************************************************************************/
20 #include FT_ADVANCES_H
21 #include FT_INTERNAL_OBJECTS_H
25 _ft_face_scale_advances( FT_Face face,
34 if ( flags & FT_LOAD_NO_SCALE )
37 if ( face->size == NULL )
38 return FT_Err_Invalid_Size_Handle;
40 if ( flags & FT_LOAD_VERTICAL_LAYOUT )
41 scale = face->size->metrics.y_scale;
43 scale = face->size->metrics.x_scale;
45 /* this must be the same scaling as to get linear{Hori,Vert}Advance */
46 /* (see `FT_Load_Glyph' implementation in src/base/ftobjs.c) */
48 for ( nn = 0; nn < count; nn++ )
49 advances[nn] = FT_MulDiv( advances[nn], scale, 64 );
55 /* at the moment, we can perform fast advance retrieval only in */
56 /* the following cases: */
60 /* - light-hinted load */
62 #define LOAD_ADVANCE_FAST_CHECK( flags ) \
63 ( flags & ( FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING ) || \
64 FT_LOAD_TARGET_MODE( flags ) == FT_RENDER_MODE_LIGHT )
67 /* documentation is in ftadvanc.h */
69 FT_EXPORT_DEF( FT_Error )
70 FT_Get_Advance( FT_Face face,
75 FT_Face_GetAdvancesFunc func;
79 return FT_Err_Invalid_Face_Handle;
81 if ( gindex >= (FT_UInt)face->num_glyphs )
82 return FT_Err_Invalid_Glyph_Index;
84 func = face->driver->clazz->get_advances;
85 if ( func && LOAD_ADVANCE_FAST_CHECK( flags ) )
90 error = func( face, gindex, 1, flags, padvance );
92 return _ft_face_scale_advances( face, padvance, 1, flags );
94 if ( error != FT_ERROR_BASE( FT_Err_Unimplemented_Feature ) )
98 return FT_Get_Advances( face, gindex, 1, flags, padvance );
102 /* documentation is in ftadvanc.h */
104 FT_EXPORT_DEF( FT_Error )
105 FT_Get_Advances( FT_Face face,
109 FT_Fixed *padvances )
111 FT_Face_GetAdvancesFunc func;
112 FT_UInt num, end, nn;
113 FT_Error error = FT_Err_Ok;
117 return FT_Err_Invalid_Face_Handle;
119 num = (FT_UInt)face->num_glyphs;
121 if ( start >= num || end < start || end > num )
122 return FT_Err_Invalid_Glyph_Index;
127 func = face->driver->clazz->get_advances;
128 if ( func && LOAD_ADVANCE_FAST_CHECK( flags ) )
130 error = func( face, start, count, flags, padvances );
134 if ( error != FT_ERROR_BASE( FT_Err_Unimplemented_Feature ) )
140 if ( flags & FT_ADVANCE_FLAG_FAST_ONLY )
141 return FT_Err_Unimplemented_Feature;
143 flags |= (FT_UInt32)FT_LOAD_ADVANCE_ONLY;
144 for ( nn = 0; nn < count; nn++ )
146 error = FT_Load_Glyph( face, start + nn, flags );
150 padvances[nn] = ( flags & FT_LOAD_VERTICAL_LAYOUT )
151 ? face->glyph->advance.y
152 : face->glyph->advance.x;
159 return _ft_face_scale_advances( face, padvances, count, flags );