ref: 3d69a198b899a6d9698bce9ef4917d78d9ee388a
dir: /src/truetype/ttgxvar.c/
/***************************************************************************/
/* */
/* ttgxvar.c */
/* */
/* TrueType GX Font Variation loader */
/* */
/* Copyright 2004, 2005, 2006 by */
/* David Turner, Robert Wilhelm, Werner Lemberg, and George Williams. */
/* */
/* 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. */
/* */
/***************************************************************************/
/***************************************************************************/
/* */
/* Apple documents the `fvar', `gvar', `cvar', and `avar' tables at */
/* */
/* http://developer.apple.com/fonts/TTRefMan/RM06/Chap6[fgca]var.html */
/* */
/* The documentation for `fvar' is inconsistant. At one point it says */
/* that `countSizePairs' should be 3, at another point 2. It should be 2. */
/* */
/* The documentation for `gvar' is not intelligible; `cvar' refers you to */
/* `gvar' and is thus also incomprehensible. */
/* */
/* The documentation for `avar' appears correct, but Apple has no fonts */
/* with an `avar' table, so it is hard to test. */
/* */
/* Many thanks to John Jenkins (at Apple) in figuring this out. */
/* */
/* */
/* Apple's `kern' table has some references to tuple indices, but as there */
/* is no indication where these indices are defined, nor how to */
/* interpolate the kerning values (different tuples have different */
/* classes) this issue is ignored. */
/* */
/***************************************************************************/
#include <ft2build.h>
#include FT_INTERNAL_DEBUG_H
#include FT_CONFIG_CONFIG_H
#include FT_INTERNAL_STREAM_H
#include FT_INTERNAL_SFNT_H
#include FT_TRUETYPE_IDS_H
#include FT_TRUETYPE_TAGS_H
#include FT_MULTIPLE_MASTERS_H
#include "ttdriver.h"
#include "ttpload.h"
#include "ttgxvar.h"
#include "tterrors.h"
#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
#define FT_Stream_FTell( stream ) \
( (stream)->cursor - (stream)->base )
#define FT_Stream_SeekSet( stream, off ) \
( (stream)->cursor = (stream)->base+(off) )
/*************************************************************************/
/* */
/* The macro FT_COMPONENT is used in trace mode. It is an implicit */
/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
/* messages during execution. */
/* */
#undef FT_COMPONENT
#define FT_COMPONENT trace_ttgxvar
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** Internal Routines *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/* */
/* The macro ALL_POINTS is used in `ft_var_readpackedpoints'. It */
/* indicates that there is a delta for every point without needing to */
/* enumerate all of them. */
/* */
#define ALL_POINTS (FT_UShort*)( -1 )
enum
{
GX_PT_POINTS_ARE_WORDS = 0x80,
GX_PT_POINT_RUN_COUNT_MASK = 0x7F
};
/*************************************************************************/
/* */
/* <Function> */
/* ft_var_readpackedpoints */
/* */
/* <Description> */
/* Read a set of points to which the following deltas will apply. */
/* Points are packed with a run length encoding. */
/* */
/* <Input> */
/* stream :: The data stream. */
/* */
/* <Output> */
/* point_cnt :: The number of points read. A zero value means that */
/* all points in the glyph will be affected, without */
/* enumerating them individually. */
/* */
/* <Return> */
/* An array of FT_UShort containing the affected points or the */
/* special value ALL_POINTS. */
/* */
static FT_UShort*
ft_var_readpackedpoints( FT_Stream stream,
FT_UInt *point_cnt )
{
FT_UShort *points;
FT_Int n;
FT_Int runcnt;
FT_Int i;
FT_Int j;
FT_Int first;
FT_Memory memory = stream->memory;
FT_Error error = TT_Err_Ok;
FT_UNUSED( error );
*point_cnt = n = FT_GET_BYTE();
if ( n == 0 )
return ALL_POINTS;
if ( n & GX_PT_POINTS_ARE_WORDS )
n = FT_GET_BYTE() | ( ( n & GX_PT_POINT_RUN_COUNT_MASK ) << 8 );
if ( FT_NEW_ARRAY( points, n ) )
return NULL;
i = 0;
while ( i < n )
{
runcnt = FT_GET_BYTE();
if ( runcnt & GX_PT_POINTS_ARE_WORDS )
{
runcnt = runcnt & GX_PT_POINT_RUN_COUNT_MASK;
first = points[i++] = FT_GET_USHORT();
/* first point not included in runcount */
for ( j = 0; j < runcnt; ++j )
points[i++] = (FT_UShort)( first += FT_GET_USHORT() );
}
else
{
first = points[i++] = FT_GET_BYTE();
for ( j = 0; j < runcnt; ++j )
points[i++] = (FT_UShort)( first += FT_GET_BYTE() );
}
}
return points;
}
enum
{
GX_DT_DELTAS_ARE_ZERO = 0x80,
GX_DT_DELTAS_ARE_WORDS = 0x40,
GX_DT_DELTA_RUN_COUNT_MASK = 0x3F
};
/*************************************************************************/
/* */
/* <Function> */
/* ft_var_readpackeddeltas */
/* */
/* <Description> */
/* Read a set of deltas. These are packed slightly differently than */
/* points. In particular there is no overall count. */
/* */
/* <Input> */
/* stream :: The data stream. */
/* */
/* delta_cnt :: The number of to be read. */
/* */
/* <Return> */
/* An array of FT_Short containing the deltas for the affected */
/* points. (This only gets the deltas for one dimension. It will */
/* generally be called twice, once for x, once for y. When used in */
/* cvt table, it will only be called once.) */
/* */
static FT_Short*
ft_var_readpackeddeltas( FT_Stream stream,
FT_Int delta_cnt )
{
FT_Short *deltas;
FT_Int runcnt;
FT_Int i;
FT_Int j;
FT_Memory memory = stream->memory;
FT_Error error = TT_Err_Ok;
FT_UNUSED( error );
if ( FT_NEW_ARRAY( deltas, delta_cnt ) )
return NULL;
i = 0;
while ( i < delta_cnt )
{
runcnt = FT_GET_BYTE();
if ( runcnt & GX_DT_DELTAS_ARE_ZERO )
{
/* runcnt zeroes get added */
for ( j = 0;
j <= ( runcnt & GX_DT_DELTA_RUN_COUNT_MASK ) && i < delta_cnt;
++j )
deltas[i++] = 0;
}
else if ( runcnt & GX_DT_DELTAS_ARE_WORDS )
{
/* runcnt shorts from the stack */
for ( j = 0;
j <= ( runcnt & GX_DT_DELTA_RUN_COUNT_MASK ) && i < delta_cnt;
++j )
deltas[i++] = FT_GET_SHORT();
}
else
{
/* runcnt signed bytes from the stack */
for ( j = 0;
j <= ( runcnt & GX_DT_DELTA_RUN_COUNT_MASK ) && i < delta_cnt;
++j )
deltas[i++] = FT_GET_CHAR();
}
if ( j <= ( runcnt & GX_DT_DELTA_RUN_COUNT_MASK ) )
{
/* Bad format */
FT_FREE( deltas );
return NULL;
}
}
return deltas;
}
/*************************************************************************/
/* */
/* <Function> */
/* ft_var_load_avar */
/* */
/* <Description> */
/* Parse the `avar' table if present. It need not be, so we return */
/* nothing. */
/* */
/* <InOut> */
/* face :: The font face. */
/* */
static void
ft_var_load_avar( TT_Face face )
{
FT_Stream stream = FT_FACE_STREAM(face);
FT_Memory memory = stream->memory;
GX_Blend blend = face->blend;
GX_AVarSegment segment;
FT_Error error = TT_Err_Ok;
FT_ULong version;
FT_Long axisCount;
FT_Int i, j;
FT_ULong table_len;
FT_UNUSED( error );
blend->avar_checked = TRUE;
if ( (error = face->goto_table( face, TTAG_avar, stream, &table_len )) != 0 )
return;
if ( FT_FRAME_ENTER( table_len ) )
return;
version = FT_GET_LONG();
axisCount = FT_GET_LONG();
if ( version != 0x00010000L ||
axisCount != (FT_Long)blend->mmvar->num_axis )
goto Exit;
if ( FT_NEW_ARRAY( blend->avar_segment, axisCount ) )
goto Exit;
segment = &blend->avar_segment[0];
for ( i = 0; i < axisCount; ++i, ++segment )
{
segment->pairCount = FT_GET_USHORT();
if ( FT_NEW_ARRAY( segment->correspondence, segment->pairCount ) )
{
/* Failure. Free everything we have done so far. We must do */
/* it right now since loading the `avar' table is optional. */
for ( j = i - 1; j >= 0; --j )
FT_FREE( blend->avar_segment[j].correspondence );
FT_FREE( blend->avar_segment );
blend->avar_segment = NULL;
goto Exit;
}
for ( j = 0; j < segment->pairCount; ++j )
{
segment->correspondence[j].fromCoord =
FT_GET_SHORT() << 2; /* convert to Fixed */
segment->correspondence[j].toCoord =
FT_GET_SHORT()<<2; /* convert to Fixed */
}
}
Exit:
FT_FRAME_EXIT();
}
typedef struct GX_GVar_Head_ {
FT_Long version;
FT_UShort axisCount;
FT_UShort globalCoordCount;
FT_ULong offsetToCoord;
FT_UShort glyphCount;
FT_UShort flags;
FT_ULong offsetToData;
} GX_GVar_Head;
/*************************************************************************/
/* */
/* <Function> */
/* ft_var_load_gvar */
/* */
/* <Description> */
/* Parses the `gvar' table if present. If `fvar' is there, `gvar' */
/* had better be there too. */
/* */
/* <InOut> */
/* face :: The font face. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
static FT_Error
ft_var_load_gvar( TT_Face face )
{
FT_Stream stream = FT_FACE_STREAM(face);
FT_Memory memory = stream->memory;
GX_Blend blend = face->blend;
FT_Error error;
FT_UInt i, j;
FT_ULong table_len;
FT_ULong gvar_start;
FT_ULong offsetToData;
GX_GVar_Head gvar_head;
static const FT_Frame_Field gvar_fields[] =
{
#undef FT_STRUCTURE
#define FT_STRUCTURE GX_GVar_Head
FT_FRAME_START( 20 ),
FT_FRAME_LONG ( version ),
FT_FRAME_USHORT( axisCount ),
FT_FRAME_USHORT( globalCoordCount ),
FT_FRAME_ULONG ( offsetToCoord ),
FT_FRAME_USHORT( glyphCount ),
FT_FRAME_USHORT( flags ),
FT_FRAME_ULONG ( offsetToData ),
FT_FRAME_END
};
if ( (error = face->goto_table( face, TTAG_gvar, stream, &table_len )) != 0 )
goto Exit;
gvar_start = FT_STREAM_POS( );
if ( FT_STREAM_READ_FIELDS( gvar_fields, &gvar_head ) )
goto Exit;
blend->tuplecount = gvar_head.globalCoordCount;
blend->gv_glyphcnt = gvar_head.glyphCount;
offsetToData = gvar_start + gvar_head.offsetToData;
if ( gvar_head.version != (FT_Long)0x00010000L ||
gvar_head.axisCount != (FT_UShort)blend->mmvar->num_axis )
{
error = TT_Err_Invalid_Table;
goto Exit;
}
if ( FT_NEW_ARRAY( blend->glyphoffsets, blend->gv_glyphcnt + 1 ) )
goto Exit;
if ( gvar_head.flags & 1 )
{
/* long offsets (one more offset than glyphs, to mark size of last) */
if ( FT_FRAME_ENTER( ( blend->gv_glyphcnt + 1 ) * 4L ) )
goto Exit;
for ( i = 0; i <= blend->gv_glyphcnt; ++i )
blend->glyphoffsets[i] = offsetToData + FT_GET_LONG();
FT_FRAME_EXIT();
}
else
{
/* short offsets (one more offset than glyphs, to mark size of last) */
if ( FT_FRAME_ENTER( ( blend->gv_glyphcnt + 1 ) * 2L ) )
goto Exit;
for ( i = 0; i <= blend->gv_glyphcnt; ++i )
blend->glyphoffsets[i] = offsetToData + FT_GET_USHORT() * 2;
/* XXX: Undocumented: `*2'! */
FT_FRAME_EXIT();
}
if ( blend->tuplecount != 0 )
{
if ( FT_NEW_ARRAY( blend->tuplecoords,
gvar_head.axisCount * blend->tuplecount ) )
goto Exit;
if ( FT_STREAM_SEEK( gvar_start + gvar_head.offsetToCoord ) ||
FT_FRAME_ENTER( blend->tuplecount * gvar_head.axisCount * 2L ) )
goto Exit;
for ( i = 0; i < blend->tuplecount; ++i )
for ( j = 0 ; j < (FT_UInt)gvar_head.axisCount; ++j )
blend->tuplecoords[i * gvar_head.axisCount + j] =
FT_GET_SHORT() << 2; /* convert to FT_Fixed */
FT_FRAME_EXIT();
}
Exit:
return error;
}
/*************************************************************************/
/* */
/* <Function> */
/* ft_var_apply_tuple */
/* */
/* <Description> */
/* Figure out whether a given tuple (design) applies to the current */
/* blend, and if so, what is the scaling factor. */
/* */
/* <Input> */
/* blend :: The current blend of the font. */
/* */
/* tupleIndex :: A flag saying whether this is an intermediate */
/* tuple or not. */
/* */
/* tuple_coords :: The coordinates of the tuple in normalized axis */
/* units. */
/* */
/* im_start_coords :: The initial coordinates where this tuple starts */
/* to apply (for intermediate coordinates). */
/* */
/* im_end_coords :: The final coordinates after which this tuple no */
/* longer applies (for intermediate coordinates). */
/* */
/* <Return> */
/* An FT_Fixed value containing the scaling factor. */
/* */
static FT_Fixed
ft_var_apply_tuple( GX_Blend blend,
FT_UShort tupleIndex,
FT_Fixed* tuple_coords,
FT_Fixed* im_start_coords,
FT_Fixed* im_end_coords )
{
FT_UInt i;
FT_Fixed apply;
FT_Fixed temp;
apply = 0x10000L;
for ( i = 0; i < blend->num_axis; ++i )
{
if ( tuple_coords[i] == 0 )
/* It's not clear why (for intermediate tuples) we don't need */
/* to check against start/end -- the documentation says we don't. */
/* Similarly, it's unclear why we don't need to scale along the */
/* axis. */
continue;
else if ( blend->normalizedcoords[i] == 0 ||
( blend->normalizedcoords[i] < 0 && tuple_coords[i] > 0 ) ||
( blend->normalizedcoords[i] > 0 && tuple_coords[i] < 0 ) )
{
apply = 0;
break;
}
else if ( !( tupleIndex & GX_TI_INTERMEDIATE_TUPLE ) )
/* not an intermediate tuple */
apply = FT_MulDiv( apply,
blend->normalizedcoords[i] > 0
? blend->normalizedcoords[i]
: -blend->normalizedcoords[i],
0x10000L );
else if ( blend->normalizedcoords[i] <= im_start_coords[i] ||
blend->normalizedcoords[i] >= im_end_coords[i] )
{
apply = 0;
break;
}
else if ( blend->normalizedcoords[i] < tuple_coords[i] )
{
temp = FT_MulDiv( blend->normalizedcoords[i] - im_start_coords[i],
0x10000L,
tuple_coords[i] - im_start_coords[i]);
apply = FT_MulDiv( apply, temp, 0x10000L );
}
else
{
temp = FT_MulDiv( im_end_coords[i] - blend->normalizedcoords[i],
0x10000L,
im_end_coords[i] - tuple_coords[i] );
apply = FT_MulDiv( apply, temp, 0x10000L );
}
}
return apply;
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** MULTIPLE MASTERS SERVICE FUNCTIONS *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
typedef struct GX_FVar_Head_ {
FT_Long version;
FT_UShort offsetToData;
FT_UShort countSizePairs;
FT_UShort axisCount;
FT_UShort axisSize;
FT_UShort instanceCount;
FT_UShort instanceSize;
} GX_FVar_Head;
typedef struct fvar_axis {
FT_ULong axisTag;
FT_ULong minValue;
FT_ULong defaultValue;
FT_ULong maxValue;
FT_UShort flags;
FT_UShort nameID;
} GX_FVar_Axis;
/*************************************************************************/
/* */
/* <Function> */
/* TT_Get_MM_Var */
/* */
/* <Description> */
/* Check that the font's `fvar' table is valid, parse it, and return */
/* those data. */
/* */
/* <InOut> */
/* face :: The font face. */
/* TT_Get_MM_Var initializes the blend structure. */
/* */
/* <Output> */
/* master :: The `fvar' data (must be freed by caller). */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
FT_LOCAL_DEF( FT_Error )
TT_Get_MM_Var( TT_Face face,
FT_MM_Var* *master )
{
FT_Stream stream = face->root.stream;
FT_Memory memory = face->root.memory;
FT_ULong table_len;
FT_Error error = TT_Err_Ok;
FT_ULong fvar_start;
FT_Int i, j;
FT_MM_Var* mmvar;
FT_Fixed* next_coords;
FT_String* next_name;
FT_Var_Axis* a;
FT_Var_Named_Style* ns;
GX_FVar_Head fvar_head;
static const FT_Frame_Field fvar_fields[] =
{
#undef FT_STRUCTURE
#define FT_STRUCTURE GX_FVar_Head
FT_FRAME_START( 16 ),
FT_FRAME_LONG ( version ),
FT_FRAME_USHORT( offsetToData ),
FT_FRAME_USHORT( countSizePairs ),
FT_FRAME_USHORT( axisCount ),
FT_FRAME_USHORT( axisSize ),
FT_FRAME_USHORT( instanceCount ),
FT_FRAME_USHORT( instanceSize ),
FT_FRAME_END
};
static const FT_Frame_Field fvaraxis_fields[] =
{
#undef FT_STRUCTURE
#define FT_STRUCTURE GX_FVar_Axis
FT_FRAME_START( 20 ),
FT_FRAME_ULONG ( axisTag ),
FT_FRAME_ULONG ( minValue ),
FT_FRAME_ULONG ( defaultValue ),
FT_FRAME_ULONG ( maxValue ),
FT_FRAME_USHORT( flags ),
FT_FRAME_USHORT( nameID ),
FT_FRAME_END
};
if ( face->blend == NULL )
{
/* both `fvar' and `gvar' must be present */
if ( (error = face->goto_table( face, TTAG_gvar,
stream, &table_len )) != 0 )
goto Exit;
if ( (error = face->goto_table( face, TTAG_fvar,
stream, &table_len )) != 0 )
goto Exit;
fvar_start = FT_STREAM_POS( );
if ( FT_STREAM_READ_FIELDS( fvar_fields, &fvar_head ) )
goto Exit;
if ( fvar_head.version != (FT_Long)0x00010000L ||
fvar_head.countSizePairs != 2 ||
fvar_head.axisSize != 20 ||
fvar_head.instanceSize != 4 + 4 * fvar_head.axisCount ||
fvar_head.offsetToData + fvar_head.axisCount * 20U +
fvar_head.instanceCount * fvar_head.instanceSize > table_len )
{
error = TT_Err_Invalid_Table;
goto Exit;
}
if ( FT_NEW( face->blend ) )
goto Exit;
/* XXX: TODO - check for overflows */
face->blend->mmvar_len =
sizeof ( FT_MM_Var ) +
fvar_head.axisCount * sizeof ( FT_Var_Axis ) +
fvar_head.instanceCount * sizeof ( FT_Var_Named_Style ) +
fvar_head.instanceCount * fvar_head.axisCount * sizeof ( FT_Fixed ) +
5 * fvar_head.axisCount;
if ( FT_ALLOC( mmvar, face->blend->mmvar_len ) )
goto Exit;
face->blend->mmvar = mmvar;
mmvar->num_axis =
fvar_head.axisCount;
mmvar->num_designs =
(FT_UInt)-1; /* meaningless in this context; each glyph */
/* may have a different number of designs */
/* (or tuples, as called by Apple) */
mmvar->num_namedstyles =
fvar_head.instanceCount;
mmvar->axis =
(FT_Var_Axis*)&(mmvar[1]);
mmvar->namedstyle =
(FT_Var_Named_Style*)&(mmvar->axis[fvar_head.axisCount]);
next_coords =
(FT_Fixed*)&(mmvar->namedstyle[fvar_head.instanceCount]);
for ( i = 0; i < fvar_head.instanceCount; ++i )
{
mmvar->namedstyle[i].coords = next_coords;
next_coords += fvar_head.axisCount;
}
next_name = (FT_String*)next_coords;
for ( i = 0; i < fvar_head.axisCount; ++i )
{
mmvar->axis[i].name = next_name;
next_name += 5;
}
if ( FT_STREAM_SEEK( fvar_start + fvar_head.offsetToData ) )
goto Exit;
a = mmvar->axis;
for ( i = 0; i < fvar_head.axisCount; ++i )
{
GX_FVar_Axis axis_rec;
if ( FT_STREAM_READ_FIELDS( fvaraxis_fields, &axis_rec ) )
goto Exit;
a->tag = axis_rec.axisTag;
a->minimum = axis_rec.minValue; /* A Fixed */
a->def = axis_rec.defaultValue; /* A Fixed */
a->maximum = axis_rec.maxValue; /* A Fixed */
a->strid = axis_rec.nameID;
a->name[0] = (FT_String)( a->tag >> 24 );
a->name[1] = (FT_String)( ( a->tag >> 16 ) & 0xFF );
a->name[2] = (FT_String)( ( a->tag >> 8 ) & 0xFF );
a->name[3] = (FT_String)( ( a->tag ) & 0xFF );
a->name[4] = 0;
++a;
}
ns = mmvar->namedstyle;
for ( i = 0; i < fvar_head.instanceCount; ++i )
{
if ( FT_FRAME_ENTER( 4L + 4L * fvar_head.axisCount ) )
goto Exit;
ns->strid = FT_GET_USHORT();
(void) /* flags = */ FT_GET_USHORT();
for ( j = 0; j < fvar_head.axisCount; ++j )
ns->coords[j] = FT_GET_ULONG(); /* A Fixed */
FT_FRAME_EXIT();
}
}
if ( master != NULL )
{
FT_UInt n;
if ( FT_ALLOC( mmvar, face->blend->mmvar_len ) )
goto Exit;
FT_MEM_COPY( mmvar, face->blend->mmvar, face->blend->mmvar_len );
mmvar->axis =
(FT_Var_Axis*)&(mmvar[1]);
mmvar->namedstyle =
(FT_Var_Named_Style*)&(mmvar->axis[mmvar->num_axis]);
next_coords =
(FT_Fixed*)&(mmvar->namedstyle[mmvar->num_namedstyles]);
for ( n = 0; n < mmvar->num_namedstyles; ++n )
{
mmvar->namedstyle[n].coords = next_coords;
next_coords += mmvar->num_axis;
}
a = mmvar->axis;
next_name = (FT_String*)next_coords;
for ( n = 0; n < mmvar->num_axis; ++n )
{
a->name = next_name;
/* standard PostScript names for some standard apple tags */
if ( a->tag == TTAG_wght )
a->name = (char *)"Weight";
else if ( a->tag == TTAG_wdth )
a->name = (char *)"Width";
else if ( a->tag == TTAG_opsz )
a->name = (char *)"OpticalSize";
else if ( a->tag == TTAG_slnt )
a->name = (char *)"Slant";
next_name += 5;
++a;
}
*master = mmvar;
}
Exit:
return error;
}
/*************************************************************************/
/* */
/* <Function> */
/* TT_Set_MM_Blend */
/* */
/* <Description> */
/* Set the blend (normalized) coordinates for this instance of the */
/* font. Check that the `gvar' table is reasonable and does some */
/* initial preparation. */
/* */
/* <InOut> */
/* face :: The font. */
/* Initialize the blend structure with `gvar' data. */
/* */
/* <Input> */
/* num_coords :: Must be the axis count of the font. */
/* */
/* coords :: An array of num_coords, each between [-1,1]. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
FT_LOCAL_DEF( FT_Error )
TT_Set_MM_Blend( TT_Face face,
FT_UInt num_coords,
FT_Fixed* coords )
{
FT_Error error = TT_Err_Ok;
GX_Blend blend;
FT_MM_Var* mmvar;
FT_UInt i;
FT_Memory memory = face->root.memory;
enum
{
mcvt_retain,
mcvt_modify,
mcvt_load
} manageCvt;
face->doblend = FALSE;
if ( face->blend == NULL )
{
if ( (error = TT_Get_MM_Var( face, NULL)) != 0 )
goto Exit;
}
blend = face->blend;
mmvar = blend->mmvar;
if ( num_coords != mmvar->num_axis )
{
error = TT_Err_Invalid_Argument;
goto Exit;
}
for ( i = 0; i < num_coords; ++i )
if ( coords[i] < -0x00010000L || coords[i] > 0x00010000L )
{
error = TT_Err_Invalid_Argument;
goto Exit;
}
if ( blend->glyphoffsets == NULL )
if ( (error = ft_var_load_gvar( face )) != 0 )
goto Exit;
if ( blend->normalizedcoords == NULL )
{
if ( FT_NEW_ARRAY( blend->normalizedcoords, num_coords ) )
goto Exit;
manageCvt = mcvt_modify;
/* If we have not set the blend coordinates before this, then the */
/* cvt table will still be what we read from the `cvt ' table and */
/* we don't need to reload it. We may need to change it though... */
}
else
{
for ( i = 0;
i < num_coords && blend->normalizedcoords[i] == coords[i];
++i );
if ( i == num_coords )
manageCvt = mcvt_retain;
else
manageCvt = mcvt_load;
/* If we don't change the blend coords then we don't need to do */
/* anything to the cvt table. It will be correct. Otherwise we */
/* no longer have the original cvt (it was modified when we set */
/* the blend last time), so we must reload and then modify it. */
}
blend->num_axis = num_coords;
FT_MEM_COPY( blend->normalizedcoords,
coords,
num_coords * sizeof ( FT_Fixed ) );
face->doblend = TRUE;
if ( face->cvt != NULL )
{
switch ( manageCvt )
{
case mcvt_load:
/* The cvt table has been loaded already; every time we change the */
/* blend we may need to reload and remodify the cvt table. */
FT_FREE( face->cvt );
face->cvt = NULL;
tt_face_load_cvt( face, face->root.stream );
break;
case mcvt_modify:
/* The original cvt table is in memory. All we need to do is */
/* apply the `cvar' table (if any). */
tt_face_vary_cvt( face, face->root.stream );
break;
case mcvt_retain:
/* The cvt table is correct for this set of coordinates. */
break;
}
}
Exit:
return error;
}
/*************************************************************************/
/* */
/* <Function> */
/* TT_Set_Var_Design */
/* */
/* <Description> */
/* Set the coordinates for the instance, measured in the user */
/* coordinate system. Parse the `avar' table (if present) to convert */
/* from user to normalized coordinates. */
/* */
/* <InOut> */
/* face :: The font face. */
/* Initialize the blend struct with `gvar' data. */
/* */
/* <Input> */
/* num_coords :: This must be the axis count of the font. */
/* */
/* coords :: A coordinate array with `num_coords' elements. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
FT_LOCAL_DEF( FT_Error )
TT_Set_Var_Design( TT_Face face,
FT_UInt num_coords,
FT_Fixed* coords )
{
FT_Error error = TT_Err_Ok;
FT_Fixed* normalized = NULL;
GX_Blend blend;
FT_MM_Var* mmvar;
FT_UInt i, j;
FT_Var_Axis* a;
GX_AVarSegment av;
FT_Memory memory = face->root.memory;
if ( face->blend == NULL )
{
if ( (error = TT_Get_MM_Var( face, NULL )) != 0 )
goto Exit;
}
blend = face->blend;
mmvar = blend->mmvar;
if ( num_coords != mmvar->num_axis )
{
error = TT_Err_Invalid_Argument;
goto Exit;
}
/* Axis normalization is a two stage process. First we normalize */
/* based on the [min,def,max] values for the axis to be [-1,0,1]. */
/* Then, if there's an `avar' table, we renormalize this range. */
if ( FT_NEW_ARRAY( normalized, mmvar->num_axis ) )
goto Exit;
a = mmvar->axis;
for ( i = 0; i < mmvar->num_axis; ++i, ++a )
{
if ( coords[i] > a->maximum || coords[i] < a->minimum )
{
error = TT_Err_Invalid_Argument;
goto Exit;
}
if ( coords[i] < a->def )
{
normalized[i] = -FT_MulDiv( coords[i] - a->def,
0x10000L,
a->minimum - a->def );
}
else if ( a->maximum == a->def )
normalized[i] = 0;
else
{
normalized[i] = FT_MulDiv( coords[i] - a->def,
0x10000L,
a->maximum - a->def );
}
}
if ( !blend->avar_checked )
ft_var_load_avar( face );
if ( blend->avar_segment != NULL )
{
av = blend->avar_segment;
for ( i = 0; i < mmvar->num_axis; ++i, ++av )
{
for ( j = 1; j < (FT_UInt)av->pairCount; ++j )
if ( normalized[i] < av->correspondence[j].fromCoord )
{
normalized[i] =
FT_MulDiv(
FT_MulDiv(
normalized[i] - av->correspondence[j - 1].fromCoord,
0x10000L,
av->correspondence[j].fromCoord -
av->correspondence[j - 1].fromCoord ),
av->correspondence[j].toCoord -
av->correspondence[j - 1].toCoord,
0x10000L ) +
av->correspondence[j - 1].toCoord;
break;
}
}
}
error = TT_Set_MM_Blend( face, num_coords, normalized );
Exit:
FT_FREE( normalized );
return error;
}
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** GX VAR PARSING ROUTINES *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/* */
/* <Function> */
/* tt_face_vary_cvt */
/* */
/* <Description> */
/* Modify the loaded cvt table according to the `cvar' table and the */
/* font's blend. */
/* */
/* <InOut> */
/* face :: A handle to the target face object. */
/* */
/* <Input> */
/* stream :: A handle to the input stream. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
/* Most errors are ignored. It is perfectly valid not to have a */
/* `cvar' table even if there is a `gvar' and `fvar' table. */
/* */
FT_LOCAL_DEF( FT_Error )
tt_face_vary_cvt( TT_Face face,
FT_Stream stream )
{
FT_Error error;
FT_Memory memory = stream->memory;
FT_ULong table_start;
FT_ULong table_len;
FT_UInt tupleCount;
FT_ULong offsetToData;
FT_ULong here;
FT_UInt i, j;
FT_Fixed* tuple_coords = NULL;
FT_Fixed* im_start_coords = NULL;
FT_Fixed* im_end_coords = NULL;
GX_Blend blend = face->blend;
FT_UInt point_count;
FT_UShort* localpoints;
FT_Short* deltas;
FT_TRACE2(( "CVAR " ));
if ( blend == NULL )
{
FT_TRACE2(( "no blend specified!\n" ));
error = TT_Err_Ok;
goto Exit;
}
if ( face->cvt == NULL )
{
FT_TRACE2(( "no `cvt ' table!\n" ));
error = TT_Err_Ok;
goto Exit;
}
error = face->goto_table( face, TTAG_cvar, stream, &table_len );
if ( error )
{
FT_TRACE2(( "is missing!\n" ));
error = TT_Err_Ok;
goto Exit;
}
if ( FT_FRAME_ENTER( table_len ) )
{
error = TT_Err_Ok;
goto Exit;
}
table_start = FT_Stream_FTell( stream );
if ( FT_GET_LONG() != 0x00010000L )
{
FT_TRACE2(( "bad table version!\n" ));
error = TT_Err_Ok;
goto FExit;
}
if ( FT_NEW_ARRAY( tuple_coords, blend->num_axis ) ||
FT_NEW_ARRAY( im_start_coords, blend->num_axis ) ||
FT_NEW_ARRAY( im_end_coords, blend->num_axis ) )
goto FExit;
tupleCount = FT_GET_USHORT();
offsetToData = table_start + FT_GET_USHORT();
/* The documentation implies there are flags packed into the */
/* tuplecount, but John Jenkins says that shared points don't apply */
/* to `cvar', and no other flags are defined. */
for ( i = 0; i < ( tupleCount & 0xFFF ); ++i )
{
FT_UInt tupleDataSize;
FT_UInt tupleIndex;
FT_Fixed apply;
tupleDataSize = FT_GET_USHORT();
tupleIndex = FT_GET_USHORT();
/* There is no provision here for a global tuple coordinate section, */
/* so John says. There are no tuple indices, just embedded tuples. */
if ( tupleIndex & GX_TI_EMBEDDED_TUPLE_COORD )
{
for ( j = 0; j < blend->num_axis; ++j )
tuple_coords[j] = FT_GET_SHORT() << 2; /* convert from */
/* short frac to fixed */
}
else
{
/* skip this tuple; it makes no sense */
if ( tupleIndex & GX_TI_INTERMEDIATE_TUPLE )
for ( j = 0; j < 2 * blend->num_axis; ++j )
(void)FT_GET_SHORT();
offsetToData += tupleDataSize;
continue;
}
if ( tupleIndex & GX_TI_INTERMEDIATE_TUPLE )
{
for ( j = 0; j < blend->num_axis; ++j )
im_start_coords[j] = FT_GET_SHORT() << 2;
for ( j = 0; j < blend->num_axis; ++j )
im_end_coords[j] = FT_GET_SHORT() << 2;
}
apply = ft_var_apply_tuple( blend,
(FT_UShort)tupleIndex,
tuple_coords,
im_start_coords,
im_end_coords );
if ( /* tuple isn't active for our blend */
apply == 0 ||
/* global points not allowed, */
/* if they aren't local, makes no sense */
!( tupleIndex & GX_TI_PRIVATE_POINT_NUMBERS ) )
{
offsetToData += tupleDataSize;
continue;
}
here = FT_Stream_FTell( stream );
FT_Stream_SeekSet( stream, offsetToData );
localpoints = ft_var_readpackedpoints( stream, &point_count );
deltas = ft_var_readpackeddeltas( stream,
point_count == 0 ? face->cvt_size
: point_count );
if ( localpoints == NULL || deltas == NULL )
/* failure, ignore it */;
else if ( localpoints == ALL_POINTS )
{
/* this means that there are deltas for every entry in cvt */
for ( j = 0; j < face->cvt_size; ++j )
face->cvt[j] = (FT_Short)( face->cvt[j] +
FT_MulFix( deltas[j], apply ) );
}
else
{
for ( j = 0; j < point_count; ++j )
{
int pindex = localpoints[j];
face->cvt[pindex] = (FT_Short)( face->cvt[pindex] +
FT_MulFix( deltas[j], apply ) );
}
}
if ( localpoints != ALL_POINTS )
FT_FREE( localpoints );
FT_FREE( deltas );
offsetToData += tupleDataSize;
FT_Stream_SeekSet( stream, here );
}
FExit:
FT_FRAME_EXIT();
Exit:
FT_FREE( tuple_coords );
FT_FREE( im_start_coords );
FT_FREE( im_end_coords );
return error;
}
/*************************************************************************/
/* */
/* <Function> */
/* TT_Vary_Get_Glyph_Deltas */
/* */
/* <Description> */
/* Load the appropriate deltas for the current glyph. */
/* */
/* <Input> */
/* face :: A handle to the target face object. */
/* */
/* glyph_index :: The index of the glyph being modified. */
/* */
/* n_points :: The number of the points in the glyph, including */
/* phantom points. */
/* */
/* <Output> */
/* deltas :: The array of points to change. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
FT_LOCAL_DEF( FT_Error )
TT_Vary_Get_Glyph_Deltas( TT_Face face,
FT_UInt glyph_index,
FT_Vector* *deltas,
FT_UInt n_points )
{
FT_Stream stream = face->root.stream;
FT_Memory memory = stream->memory;
GX_Blend blend = face->blend;
FT_Vector* delta_xy;
FT_Error error;
FT_ULong glyph_start;
FT_UInt tupleCount;
FT_ULong offsetToData;
FT_ULong here;
FT_UInt i, j;
FT_Fixed* tuple_coords = NULL;
FT_Fixed* im_start_coords = NULL;
FT_Fixed* im_end_coords = NULL;
FT_UInt point_count, spoint_count = 0;
FT_UShort* sharedpoints = NULL;
FT_UShort* localpoints = NULL;
FT_UShort* points;
FT_Short *deltas_x, *deltas_y;
if ( !face->doblend || blend == NULL )
return TT_Err_Invalid_Argument;
/* to be freed by the caller */
if ( FT_NEW_ARRAY( delta_xy, n_points ) )
goto Exit;
*deltas = delta_xy;
if ( glyph_index >= blend->gv_glyphcnt ||
blend->glyphoffsets[glyph_index] ==
blend->glyphoffsets[glyph_index + 1] )
return TT_Err_Ok; /* no variation data for this glyph */
if ( FT_STREAM_SEEK( blend->glyphoffsets[glyph_index] ) ||
FT_FRAME_ENTER( blend->glyphoffsets[glyph_index + 1] -
blend->glyphoffsets[glyph_index] ) )
goto Fail1;
glyph_start = FT_Stream_FTell( stream );
/* each set of glyph variation data is formatted similarly to `cvar' */
/* (except we get shared points and global tuples) */
if ( FT_NEW_ARRAY( tuple_coords, blend->num_axis ) ||
FT_NEW_ARRAY( im_start_coords, blend->num_axis ) ||
FT_NEW_ARRAY( im_end_coords, blend->num_axis ) )
goto Fail2;
tupleCount = FT_GET_USHORT();
offsetToData = glyph_start + FT_GET_USHORT();
if ( tupleCount & GX_TC_TUPLES_SHARE_POINT_NUMBERS )
{
here = FT_Stream_FTell( stream );
FT_Stream_SeekSet( stream, offsetToData );
sharedpoints = ft_var_readpackedpoints( stream, &spoint_count );
offsetToData = FT_Stream_FTell( stream );
FT_Stream_SeekSet( stream, here );
}
for ( i = 0; i < ( tupleCount & GX_TC_TUPLE_COUNT_MASK ); ++i )
{
FT_UInt tupleDataSize;
FT_UInt tupleIndex;
FT_Fixed apply;
tupleDataSize = FT_GET_USHORT();
tupleIndex = FT_GET_USHORT();
if ( tupleIndex & GX_TI_EMBEDDED_TUPLE_COORD )
{
for ( j = 0; j < blend->num_axis; ++j )
tuple_coords[j] = FT_GET_SHORT() << 2; /* convert from */
/* short frac to fixed */
}
else if ( ( tupleIndex & GX_TI_TUPLE_INDEX_MASK ) >= blend->tuplecount )
{
error = TT_Err_Invalid_Table;
goto Fail3;
}
else
{
FT_MEM_COPY(
tuple_coords,
&blend->tuplecoords[(tupleIndex & 0xFFF) * blend->num_axis],
blend->num_axis * sizeof ( FT_Fixed ) );
}
if ( tupleIndex & GX_TI_INTERMEDIATE_TUPLE )
{
for ( j = 0; j < blend->num_axis; ++j )
im_start_coords[j] = FT_GET_SHORT() << 2;
for ( j = 0; j < blend->num_axis; ++j )
im_end_coords[j] = FT_GET_SHORT() << 2;
}
apply = ft_var_apply_tuple( blend,
(FT_UShort)tupleIndex,
tuple_coords,
im_start_coords,
im_end_coords );
if ( apply == 0 ) /* tuple isn't active for our blend */
{
offsetToData += tupleDataSize;
continue;
}
here = FT_Stream_FTell( stream );
if ( tupleIndex & GX_TI_PRIVATE_POINT_NUMBERS )
{
FT_Stream_SeekSet( stream, offsetToData );
localpoints = ft_var_readpackedpoints( stream, &point_count );
points = localpoints;
}
else
{
points = sharedpoints;
point_count = spoint_count;
}
deltas_x = ft_var_readpackeddeltas( stream,
point_count == 0 ? n_points
: point_count );
deltas_y = ft_var_readpackeddeltas( stream,
point_count == 0 ? n_points
: point_count );
if ( points == NULL || deltas_y == NULL || deltas_x == NULL )
; /* failure, ignore it */
else if ( points == ALL_POINTS )
{
/* this means that there are deltas for every point in the glyph */
for ( j = 0; j < n_points; ++j )
{
delta_xy[j].x += FT_MulFix( deltas_x[j], apply );
delta_xy[j].y += FT_MulFix( deltas_y[j], apply );
}
}
else
{
for ( j = 0; j < point_count; ++j )
{
delta_xy[localpoints[j]].x += FT_MulFix( deltas_x[j], apply );
delta_xy[localpoints[j]].y += FT_MulFix( deltas_y[j], apply );
}
}
if ( localpoints != ALL_POINTS )
FT_FREE( localpoints );
FT_FREE( deltas_x );
FT_FREE( deltas_y );
offsetToData += tupleDataSize;
FT_Stream_SeekSet( stream, here );
}
Fail3:
FT_FREE( tuple_coords );
FT_FREE( im_start_coords );
FT_FREE( im_end_coords );
Fail2:
FT_FRAME_EXIT();
Fail1:
if ( error )
{
FT_FREE( delta_xy );
*deltas = NULL;
}
Exit:
return error;
}
/*************************************************************************/
/* */
/* <Function> */
/* tt_done_blend */
/* */
/* <Description> */
/* Frees the blend internal data structure. */
/* */
FT_LOCAL_DEF( void )
tt_done_blend( FT_Memory memory,
GX_Blend blend )
{
if ( blend != NULL )
{
FT_UInt i;
FT_FREE( blend->normalizedcoords );
FT_FREE( blend->mmvar );
if ( blend->avar_segment != NULL )
{
for ( i = 0; i < blend->num_axis; ++i )
FT_FREE( blend->avar_segment[i].correspondence );
FT_FREE( blend->avar_segment );
}
FT_FREE( blend->tuplecoords );
FT_FREE( blend->glyphoffsets );
FT_FREE( blend );
}
}
#endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */
/* END */